Subject: [gto2] [gto] Re: ROCKER ARM RATIO 1.65 VS 1.5 Date: Sun, 18 Jul 1999 09:45:03 -0400 From: Ted D Schultz According to Crane Cams, http://www.cranecams.com/camvtfaq.htm in addition to the added lift the duration will change
about 2 to 4 degrees when changing rocker arm ratio from 1.5 to 1.6. Ted Schultz 69 LeMans Convertible << Actually, Duration will change. Just not a whole lot! >> Actually No it will not, because the rocker arm ratio, will not effect when the lifter starts
being lifted buy the cam lobe. Thus duration is not effected. When the cam lobe is lifting the
lifter is the only time you measure duration, regardless of rocker arm ratio. So, when the
lifter is off the lobe no rocker am ratio will keep the valve open any longer. So, you could
have any rocker arm ratio and it would never effect duration, because if the lifter isn't going
up, it just isn't, and when the lifter is all the way down, it's all the way down. It is simple
physics, if there is no action there is no reaction, so if the cam isn't lifting the lifter,
regardless of the ratio, it will not be opening the valve. Joey Subject: [gto2] 1.5 vs. 1.65 rockers Date: Tue, 20 Jul 1999 16:30:13 -0500 From: Glenn Watson I know it's been a few days since this thread, but if anybody is still interested there is a
very informative discussion about 1.5 vs. 1.65 ratio rockers on Classical Pontiac. Topic #9706. Later, Glenn Subject: [gto2] Tests with rocker arm ratio changes Date: Thu, 5 Aug 1999 08:44:37 EDT From: ACIChgo Here is a link to a Jim Hand article on camshafts. Read down through the article and you will
find some results when he changed to 1.65 rockers. It did have a positive effect on performance. Jim Hand Article #5 Bruce Subject: [gto2] Re: Tests with rocker arm ratio changes Date: Thu, 05 Aug 1999 17:55:13 CST From: Firefighter Roy DeSoto << hey gang, in regards to rocker ratio I had heard that if you run a cam with RA 4 specs and
1:65 rockers that you could run into coil bind on valve springs on heads other than RA 4 heads.
Is this true? Also had heard >> According to Pete McCarthy's "55-79" book the 041 cam and 1.65 rockers will not work with stock
springs (p. 66). Aftermarket springs are a necessity. << that some guys run 1:50 on intake and 1:65 on exhaust with positive results. Is this true?
Have read Hands articles and are interesting. He also seems to >> In the same book McCarthy mentions that Pontiac heads have good exhaust flow above .400" lift.
1.65s would certainly help here. Brad Subject: [gto2] Re: Follow the bouncing rocker ratio Date: Fri, 6 Aug 1999 11:09:33 EDT From: Joey455FB << to me it just seems like your putting a band aid on insufficient intake/head flow... IMHO Bruce >> This was just what I thought. It is a lot of work, but that's what we are doing when we build a
motor and port the heads. This is to get away from the inconsistent factory flow #'s. In case
any of you want to run your cyl. more evenly these are something's I have found to make a
difference, this is thru trial and error not from a magazine article. 1. Use an open plenum intake (TORKER II is good, VICTOR is better, Sheet Metal is best). 2. Have heads ported the same (any good shop will do this anyway). 3. Port the intake so all the port entrances and exits are the same. 4. Use equal length headers. 5. Run the coolant from the back of the heads, to right under the thermostat. 6. Make sure all runner meet the head the same by looking down them w/a flashlite w/the head
installed. 7. Look down the carb into the intake and make sure all the flow paths for the air are the
same under each barrel (if not port the intake till they are). Well, that's about all I can
think of right now. I know all these things are not plausible on a street or resto. car, but
every one of these things will bring you closer to a more evenly running motor. Joey Subject: Re: [GTO] [Fwd: Dudette has questions about Ram Air V] Date: Sun, 16 Jan 2000 08:04:44 -0600 From: Terry Nixon I'm not very conversant with all the individual detail differences between the flavors of RA
engines, but the fundamental difference between the RA V and all the others is that the head
was completely different, as far as, port runner placement. You need to look at a picture, but
instead of the two center exhaust ports being adjacent, they're separated. The ports are not
equidistant from each other, either, but they're grouped a little into a front pair and a back
pair. Additionally, to the averagely experienced person of this EFI age, "T. P." means "tuned
port", where it actually in this case means "tunnel port". The pushrods run directly through
the intake ports in steel tubing "tunnels", as in the old Ford 427 tunnel-port engines. There
was a fairly good article in the last couple of years about the RA V, but I forget whether it
was in HPP or Pontiac Enthusiast. Terry mattingly wrote: Forwarding these technical questions to the list. I can't answer a single Ram Air engine
question... << Like, is your tuned port a function of the exhaust resonance versus lift duration’s caused
by the cam bearing texture? Or something like that... ;> -- [] Sean Mattingly, The Ultimate GTO Picture Site [] featuring 1964 through 1974 Pontiac GTO cars. [] Our NEW URL is http://UltimateGTO.com >> Subject: Ram Air V Date: Fri, 14 Jan 2000 21:06:49 -0700 From: "Marilyn Robinson" I just became really interested in the Ram Air V after reading that it produced 475-500
H.P. I am the current owner of a set of Ram Air III heads & as I was buying the valve train
parts had found that the cam duration & lift of the R.A. III & IV were similar unlike compared
to the R.A. I & II and that the stock R.A. III used 1.5 lift rocker arms & the R.A. IV used
1.65 rockers. What I was wondering what size cam & rockers did the R.A. V use? What size valves
did the R.A. V use compared to the R.A. III & IV? What are the differences of the exhaust
runners between the R.A. III & IV, since they are unable to use the same headers? And how do
they compare to the R.A. V? And what is the deal with it being tuned port, is it just the
intake manifold or does it also something to do with the intake runners & combustion chambers,
what about the exhaust manifolds? How do these compare to the other Ram Air versions? Subject: [GTO] 68 Goat Valve Covers Date: Fri, 28 Apr 2000 01:20:51 EDT From: Spikaliba Hi all -- any comments would be appreciated. My engine compartment is about ready to accept my almost rebuilt 400(WT) and I may be looking
at a problem. I installed a set of Harland Sharp roller rockers (1.5 ratio) onto a new set of
screw in studs (7/16 top and bottom) and without a proper adjustment as yet it appears that the
stock chrome valve covers may not be tall enough. As I am attempting to maintain a stock
exterior in the engine compartment (as well as the rest of the Goat) I am concerned. Is there a
way to make the covers taller which will enable me to use the stock covers? Could the problem
go away with proper adjustment? TIA for your time and help. tom 68 goat ragtop Subject: Re: [GTO] 68 Goat Valve Covers Date: Fri, 28 Apr 2000 02:30:00 EDT From: Green68gto Tom- I'm running Jim Butler roller rockers and 7/16 screw in studs on my '68 with stock valve covers.
You can either double up on your valve cover gaskets or order extra thick ones from Butler
Performance and your stock covers should fit just fine. I think it's a tight fit, but I haven't
experienced any problems since I put them on about a year ago. Ken Subject: Re: [GTO] 68 Goat Valve Covers Date: Fri, 28 Apr 2000 02:35:37 EDT From: Lemans411 I’VE SEEN VALVE COVER SPACERS FOR SALE ALSO ABOUT AN INCH THICK FOR CLEARANCE. Rob Senkyr lemans411 67 LeMans Mnpls., MN Subject: Re: [[GTO] 68 Goat Valve Covers] Date: 28 Apr 00 13:05:43 PDT From: Scott Holten From the advice of Jerry (Goatman) I checked mine ('67 400 w/670 heads and Harland Sharp 1.5
rockers) with no gasket on the valve cover (and unbolted of course) and turned the engine over
by hand. The valve cover did not lift...so I used a single rubber valve cover gasket. There has
got to be at least .100 clearance between the rockers and the valve covers. BTW, I did run this
Engine last night again and there are no dings in the covers so all is well. Scott Subject: Re: [Re: [[GTO] 68 Goat Valve Covers]] Date: 28 Apr 00 15:37:41 PDT From: Scott Holten I should have added that I am running my Engine with an 068 Cam. If the lift of your cam is
much higher than the 068 then you may have to double gasket your valve covers. Scott Subject: [GTO] Variable Ratio Rockers Date: Sat, 10 Jun 2000 02:06:45 -0700 From: "Gary L. Travis" Hey All! Has anyone of you guys that race/etc. used these yet? They were featured in the May 2000 issue
of Hot Rod. They are called, Hotrockers and are from; Evroc Industries. Seems like the
principal should work, but are they applicable in the real world? If you'all want to check them
out the URL is: http://www.hotrocker.com/ What do you all think? Gary T. 64 GTO Htp. 75 455 Grand Am Subject: Re: [GTO] Variable Ratio Rockers Date: Sat, 10 Jun 2000 15:25:09 EDT From: GoatmanPaulC Sounds interesting Gary. Never heard of them, but am curious how they really work. I wonder if
they make them for Pontiacs and how much. Goatman Subject: Re: [GTO] Variable Ratio Rockers Date: Sat, 10 Jun 2000 18:11:36 -0700 From: "Gary L. Travis" According to the article and their FAQ page, they will be available for Pontiac V8's in about
4-6 weeks at a projected price of $795 for a set. Their dyno test results page show them
developing over 360 ft/lbs of torque at 3500 rpm, impressive. I may think about them for the
455 going into the Grand Am. We'll have to see what the grapevine says. You know, always better from experience of use over
the "industry rags". TeeHee. Gary T. 64 GTO Htp. 75 455 Grand Am Subject: Re: [GTO] Variable Ratio Rockers Date: Sun, 11 Jun 2000 04:28:48 EDT From: GoatmanPaulC The only small problem I see is that you will have to grind the push rod holes towards the stud
quite a bit so the push rod won't hit when these babies go to 1.9:1 ratio. 1.65:1 rockers cause
the push rods to almost hit. Something to think about before the heads go together. Goatman Subject: Re: [GTO] Variable Ratio Rockers Date: Tue, 13 Jun 2000 02:33:13 -0700 From: "Gary L. Travis" Paul, That is what I was thinking. As I said, I'm sure the Poncho guru's like McCarthy, Butler and
the likes will take a look at this new innovation coming out. The grapevine will tell the tale. Gary T. 64 GTO Htp. 75 455 Grand Am Subject: Re: [GTO] What’s up on Variable Ratio Rockers ? Date: Tue, 13 Jun 2000 02:41:21 -0700 From: "Gary L. Travis" According to their website, they will be available in about 4-6 weeks at around, $795 for a set.
Goatman Paul C. brought up a good point about when they go to the 1.9:1 position. What about
pushrod clearance? I'm going to eMail them and see what their answer is about this on Poncho
heads. I'll post the answer. Gary T. 64 GTO Htp. 75 455 Grand Am Subject: Pushrod Clearance Question? Date: Thu, 22 Jun 2000 11:56:42 -0700 From: "Gary L. Travis" To: info@hotrocker.com Hi, Read the article in the May 2K, "Hot Rod" about your new innovation. It sounds great! I was
discussing them with some other enthusiasts, on the GTO E-mail List, and a question arose about
the system. When the system switches over to the 1.65:1 or 1.9:1 position is there an altering
of the pushrod angle/clearance? I am sure you are aware that in standard Pontiac heads, other
than RA IU heads, when using 1.65:1 rockers there is need to make modifications for clearance.
Or does the system, not change the pushrod geometry, in it's change from one ratio to another? Also, are they applicable to non-computer controlled GM engines? Thanks much for your time and efforts to the motorsport performance world. I will pass on your
response to the rest of the list. There is great interest in them from the members who both
race or have street beasts. Sincere Thanks, Gary T. 64 GTO Htp. 75 455 Grand Am Subject: [GTO] Re: Variable Ratio Rockers (Answer) Date: Tue, 04 Jul 2000 15:33:19 -0700 From: "Gary L. Travis" Hey all! Bill finally got back to me about the clearance question, on the "Hotrocker" and another one I
had. Here's his post. Gary T. 64 GTO Htp. 75 455 Grand Am Subject: Re: Pushrod Clearance Question? Date: Tue, 04 Jul 2000 16:19:23 CDT From: "william entzminger" HOTROCKER AVAILABLE!!!!!! Thanks for your interest! The Hotrocker is designed for your rocker arms to stroke on the same plane they do w/your stock
rockers. Changing from one ratio to another doesn't change the position of the pushrod. The
Hotrocker is definitely applicable to non computerized GM cars as it has its own stand alone
ECM to control the shift points. We are taking orders for July delivery on these engines. The price for V-8s is $795 and $695 for V-6s, plus a thirty dollar shipping and handling charge.
Texas residents need to add sales tax. We are currently accepting payments by check and credit
card. The purchase price includes all necessary parts for the installation except for valve
covers and valve cover gaskets. Shipment is planned to begin around July 15. Website will be
updated regularly. You can telephone us at 972-335-2464 for further assistance or to place an
order. AMC V-8 Chevy small block Chevy 90 V-6 Dodge Magnum V-6 and V-8 Ford Windsor V-8 Oldsmobile V-8 Pontiac V-8 We plan to offer Hotrockers for these engines in August. Buick 3800 V-6 Late model Chevy 60 V-6 Inline valves Dodge Magnum V-10 Viper V-10 Hotrockers will be available for these engines in late 2000. Buick V-6 V-8 (factory shaft system) Cadillac V-8 (425,472,500) Ford FE V-8 Jeep 4 and 6 cylinders MoPar V-6 V-8 Non-Magnum Keep in touch Bill Subject: Re: [GTO] Re: Variable Ratio Rockers (Answer) Date: Tue, 4 Jul 2000 23:27:02 EDT From: LP10978 800$$$ allot of dough for me at the time. Holy sh*t, guess if I want these ill have to save my
pennies for quite awhile. Built my whole motor for less than $800. Subject: RE: [GTO] Re: Variable Ratio Rockers (Answer) Date: Tue, 04 Jul 2000 21:58:24 CST From: "The Harper Valley P.T.A." << Bill finally got back to me about the clearance question, on the "Hotrocker" and another one
I had. Here's his post. (snip) >> Reads like a canned reply to me... Brad Subject: [GTO] Engine Accessories help?! Date: Wed, 26 Jul 2000 18:12:30 -0500 From: "Chris Bilich" When the new 455 goes in, I'll need to pick some rocker arms and a torque converter. I want to
have some good 1.5 rocker arms that are affordable, but reduce friction (probably can't afford
full roller rockers), and a ~1900 rpm stall converter, so I can get off the line a bit. The cam
is a GM performance cam (218/228, .460/.480@.050, I believe), limited to 5500 rpm, street
driven Austin to Dallas all the time, and raced on Friday nites here and there. What parts do y'all recommend/have used with success?!?! I'm considering: 1) CompCams Roller-tip 1.52:1 rocker arms (PN# CCA-1451, 7/16" stud) on the 7K3 heads ($133/set
of 16). 2) TCI Saturday Night Special (PN# 241500 small bolt pattern, 241501 large pattern, 241502 BOP
pattern....all according to the PAW catalog) (about $145/each). ***both PAW, Summit offer their "house" converters that stall at "500-600 over stock" for about
$90, instead of $145 for the TCI. Good/bad? Pros/cons? Thanks, Chris Subject: Re: [GTO] Engine Accessories help?! Date: Wed, 26 Jul 2000 19:26:00 EDT From: Goats3 << What parts do y'all recommend/have used with success?!?! I'm considering: 1) CompCams Roller-tip 1.52:1 rocker arms (PN# CCA-1451, 7/16" stud) on the 7K3 heads ($133/set
of 16). >> Those are the rockers that are on my 69 400. A little noisier than stock, but nothing obnoxious.
So far, no problems. Kenny L Subject: Re: [GTO] Engine Accessories help?! Date: Wed, 26 Jul 2000 21:25:15 EDT From: Green68gto I went with Jim Butler Roller Rockers- $199 for the set. I debated on the roller tipped and
stamped steel, but figured I might as well go all the way. So far, I love them. I've been on a
budget before (the FIRST time I built my engine) and went with a fair amount of PAW stuff.
Everything I got from them was name brand except my torque converter which was their house
brand. It's the only part in the drive train that I've had a problem with. I had a fin break loose and
rattle around inside the converter. Very annoying and a PITA to fix. Anyhow, I've had other
friends who have ordered PAW brand stuff before and have had similar problems with quality. My
2 cents is PAW is fine, as long as you order the name brand stuff. Ken '68 GTO Subject: Re: [GTO] Engine Accessories help?! Date: Wed, 26 Jul 2000 22:35:22 EDT From: RAMAIR406 Yes, I agree the base price for their engine rebuild kit cost $217 and is very appealing. But,
the parts are not name brand. I upgraded my parts to name brand, such as, Felpro, moly rings,
dbl. chain. End total is $275 and I think it’s probably worth it. Subject: Re: [GTO] Engine Accessories help?! Date: Thu, 27 Jul 2000 03:59:24 EDT From: Corpkilr1 Chris, Go w/1.65 full rollers. Under $200.00 and a 2500 converter. If you don't, you will kick
yourself later. -corpkilr- Subject: RE: [GTO] Engine Accessories help?! Date: Thu, 27 Jul 2000 06:23:14 -0400 From: "mike" I agree, except watch on the 1.65 rockers that you have the proper clearance to use them. Mike Subject: Re: [GTO] Engine Accessories help?! Date: Thu, 27 Jul 2000 19:52:24 -0500 From: "Chris Bilich" 1) Which roller rockers should I get? How much are they? How much more power will they give me?
Will the engine still be a primarily a street motor? If you need more info, ask and I'll send
it out. The cam is a .454/.480 GM Performance cam. That makes the lifts .500/.528 lift w/the
1.65 rockers. I know how to enlarge the pushrod guide holes, but how can I know for sure if I
can use the 1.65's instead? 2) Will the 2500 stall converter still perform well at highway speeds, and not totally KILL my
rpm's and mileage (about 13 mpg highway now, w/2.87 gears) Chris Subject: Re: [GTO] Engine Accessories help?! Date: Thu, 27 Jul 2000 01:26:00 -0500 From: "Chris Bilich" So, for the extra $70 or so over the roller tips, it was worth it, eh? Did they come w/poly-lock nuts, or will I need a set of them myself? Chris ps - I've had similar experiences w/Summit headers. Decent, but not perfect. Ya get what ya pay
for, I guess! -----Original Message----- From: Green68gto Date: Wednesday, July 26, 2000 8:27 PM Subject: Re: [GTO] Engine Accessories help?! << I went with Jim Butler Roller Rockers- $199 for the set. I debated on the roller tipped and
stamped steel, but figured I might as well go all the way. So far, I love them. I've been on a
budget before (the FIRST time I built my engine) and went with a fair amount of PAW stuff.
Everything I got from them was name brand except my torque converter which was their house
brand. It's the only part in the drive train that I've had a problem with. I had a fin break loose and
rattle around inside the converter. Very annoying and a PITA to fix. Anyhow, I've had other
friends who have ordered PAW brand stuff before and have had similar problems with quality. My
2 cents is PAW is fine, as long as you order the name brand stuff. Ken '68 GTO >> Subject: Re: [GTO] Engine Accessories help?! Date: Fri, 28 Jul 2000 01:36:59 EDT From: GoatmanPaulC << So, for the extra $70 or so over the roller tips, it was worth it, eh? Did they come w/poly-lock nuts, or will I need a set of them myself? Chris ps - I've had similar experiences w/ summit headers. Decent, but not perfect. Ya get what ya
pay for, I guess! >> They come with Poly-Locks generally. The Harland-Sharp's definitely do come with them. Goatman Subject: [GTO] posi-locks Date: Sun, 20 Aug 2000 12:06:50 -0600 From: Dan I know this has been covered, but I inadvertently erased my saved mail files. What is the correct method for tightening posilock rocker nuts/ Thanks Dan Subject: Re: [GTO] posi-locks Date: Sun, 20 Aug 2000 13:22:28 -0700 From: rickgto << I know this has been covered, but I inadvertently erased my saved mail files. What is the correct method for tightening posilock rocker nuts/ Thanks Dan >> Make sure lifter is on base circle (valve closed past ramp), turn down adjuster nut while
spinning p-rod back and forth with other hand until all play is removed, WITHOUT moving lifter
cup down into body. You should JUST feel the p-rod get hard to spin. Then turn an additional
1/2-1 full turn and lock it. Rick Subject: Re: [GTO] posi-locks Date: Mon, 21 Aug 2000 01:15:00 EDT From: DATHOE Bruce Fulper has the correct method for installing posilocks on his website FAQ section. Check
it out: http://www.pontiacpower.com/performance.htm I’m no Fulper fan, just for the record,
but correct info is correct info. Dave Subject: [GTO] 1.65s on a smogger 400? Date: Wed, 06 Sep 2000 17:13:31 CST From: Maxwell Edison (majoring in medicine) Has anyone ever run 1.65 rockers on an otherwise stock low-CR '70s smogger 400? If so, what
were the observed results? Anyone have a set of used 1.65 rockers (for bottlenecks) that they'd
part with or loan out temporarily? Brad Subject: Re: [GTO] 1.65s on a smogger 400? Date: Sat, 9 Sep 2000 02:13:54 EDT From: GoatmanPaulC << Has anyone ever run 1.65 rockers on an otherwise stock low-CR '70s smogger 400? If so, what
were the observed results? Anyone have a set of used 1.65 rockers (for bottlenecks) that they'd
part with or loan out temporarily? Brad >> Brad, I wouldn't waste them on that engine. I really don't think that cam would really benefit
from them. Also, you should change to 7/16 studs if you do use them, but the 3/8 will probably
be fine since it is a mild cam. Goatman Subject: [GTO] intakes and Rockers (was 2BBL to 4BBL conversion) Date: Thu, 14 Sep 2000 13:56:19 -0500 << I agree on the performance gains of the Edelbrock manifold. There ARE none! If anything they
don't perform as well since you lose quite a few pounds by installing one. The Pontiac Q-jet
intake is an excellent intake and is hard to beat unless you are all out racing. If you have
the secondary air valves on >> So, basically if I have say a '67 4bbl intake bolted up to a 400 with 670 heads, with a RA IU
cam, there's really no reason to spend the cash to get a Performer or Performer RPM? I plan on
picking up that very engine in the next few days and I was going to put a Performer RPM on it,
but if that's the case, I'll just stick with the standard intake. Are there any years of intakes to stay away from? Also, someone (maybe Goatman) mentioned no benefit from 1.65 rockers, how about going with
roller rockers? Thanks, Phil Subject: RE: [GTO] intakes and Rockers (was 2BBL to 4BBL conversion) Date: Thu, 14 Sep 2000 14:02:18 CST << So basically if I have say a '67 4bbl intake bolted up to a 400 with 670 heads, with a RA IU
cam, there's really no reason to spend the cash to get a Performer or Performer RPM? I plan on
picking up that very engine in the next few days and I was going to put a Performer RPM on it,
but if that's the case, I'll just stick with the standard intake. >> The Performer RPM is designed for a slightly higher powerband than the regular Performer. I
wouldn't switch from a stock intake to a Performer but if the rest of the engine justified it
I'd go with a Performer RPM... << Are there any years of intakes to stay away from? >> Factory-wise, all '75-79 intakes. << Also, someone (maybe Goatman) mentioned no benefit from 1.65 rockers, how about going with
roller rockers? >> Full rollers? Like the Harland Sharps I want? ;^) It certainly won't hurt but depending on the
rocker you might have to run thick or doubled valve cover gaskets, or dimple the valve cover. Brad Subject: Re: [GTO] intakes and Rockers (was 2BBL to 4BBL conversion) Date: Fri, 15 Sep 2000 01:51:57 EDT << Full rollers? Like the Harland Sharps I want? ;^) It certainly won't hurt but depending on
the rocker you might have to run thick or doubled valve cover gaskets, or dimple the valve cover. Brad >> My Harland-Sharp rollers fit under my stock 69 valve covers with regular gaskets. Also, one
should go with 7/16 studs and Poly-Locks when going to rollers, especially 1.65:1's. Goatman Subject: Re: [GTO] intakes and Rockers (was 2BBL to 4BBL conversion) Rockers Date: Fri, 15 Sep 2000 01:49:03 EDT << I agree on the performance gains of the Edelbrock manifold. There ARE none! If anything
they don't perform as well since you lose quite a few pounds by installing one. The Pontiac
Q-jet intake is an excellent intake and is hard to beat unless you are all out racing. If you
have the secondary air valves on. So basically if I have say a '67 4bbl intake bolted up to a 400 with 670 heads, with a RA IU
cam, there's really no reason to spend the cash to get a Performer or Performer RPM? I plan on
picking up that very engine in the next few days and I was going to put a Performer RPM on it,
but if that's the case, I'll just stick with the standard intake. Are there any years of intakes to stay away from? Also, someone (maybe Goatman) mentioned no benefit from 1.65 rockers, how about going with
roller rockers? Thanks, Phil >> Phil, the Performer RPM will give slight gains with a big cam like that. Maybe a tenth or two in the 1/4. The 67 intake is not as preferred as the 68-71 intake because
of the exhaust passage under the carb, requiring the use of a thin steel gasket to keep the
carb from burning up. The 68-71 intakes do not have this. The later intakes were not as good
and starting somewhere around 73-74 they started using EGR valves. When I said no gains from
1.65:1 rockers, I meant on a stock engine with a small cam. There would be a benefit, just not
enough to justify the cost, in my opinion. Roller rockers always add power, if from nothing
else, from loss of friction. I'm sure Joey [< A HREF="http://www.hightorquemotorsports.com">hightorquemotorsports.com] High Torque Motorsports
could set you up with a good set. Your welcome Joey! Goatman Subject: Re: [GTO] intakes and Rockers (was 2BBL to 4BBL conversion) Rockers Date: Fri, 15 Sep 2000 07:57:13 -0500 << Phil, the Performer RPM will give slight gains with a big cam like that. Maybe a tenth or two in the 1/4. The 67 intake is not as preferred as the 68-71 intake because
of the exhaust passage under the carb, requiring the use >> OK, I think I'll go back to the RPM idea then. :-) Any idea if they'll fit under a '69
Firebird 400 hood? I've got one of the old performer intakes (P4B I think it is) on there now
and it works with a dropped air cleaner. << around 73-74 they started using EGR valves. When I said no gains from 1.65:1 rockers, I
meant on a stock engine with a small cam. There would be a benefit, just not enough to justify
the cost, in my opinion. Roller rockers always add power, if from nothing else, from loss of
friction. I'm sure Joey [< A HREF="http://www.hightorquemotorsports.com">hightorquemotorsports.com] could set you up with a good set. Your welcome
Joey! >> How difficult is it to switch to 7/16 studs? I'm guessing that the heads would have to be
drilled/tapped or would they? Is this something I can do with the heads bolted to the car or is
it a machine shop item. I'm not real concerned about 1.65, I think with 1.5 and that cam it'll
run good enough to move that 'bird around, but I would like to go with rollers. :-) Thanks, Phil Subject: Re: [GTO] intakes and Rockers (was 2BBL to 4BBL conversion) Rockers Date: Fri, 15 Sep 2000 08:05:08 CST << From: "Phil Shaffer" How difficult is it to switch to 7/16 studs? I'm guessing that the
heads would have to be drilled/tapped or would they? Is this something I can do with the heads
bolted to the car or is it a machine shop item. I'm not real concerned about 1.65, I think with
1.5 and that cam it'll run good enough to move that 'bird around, but I would like to go with
rollers. :-) >> IIRC, #670s came from the factory with screw-in studs so it's simply a matter of removing the
originals and installing the new ones. Yes, you can do it with the heads on the engine. Brad Subject: Re: [GTO] intakes and Rockers (was 2BBL to 4BBL conversion) Rockers Date: Fri, 15 Sep 2000 08:13:12 -0500 << IIRC, #670s came from the factory with screw-in studs so it's simply a matter of removing
the originals and installing the new ones. Yes, you can do it with the heads on the engine. >> Whooo-hoo, I can handle bolt-ons. :-) Thank ya! Phil Subject: Re: [GTO] intakes and Rockers (was 2BBL to 4BBL conversion) Rockers Date: Fri, 15 Sep 2000 08:44:23 CST << From: "Phil Shaffer" Whooo-hoo, I can handle bolt-ons. :-) Thank ya! >> Well, before you go dancing in the street I think someone should at least confirm that the
#670s have screw-in studs. ;^) I'm sure someone here or on Poncho will know for sure. Brad Subject: Comp cams roller tip rocker noise. Date: Tue, 3 Oct 2000 00:43:34 EDT From: GoatmanPaulC Has anyone running Comp cams roller tip rockers experienced noisy operation from them? The
reason I ask is because a friend of mine has a 454 [yeah I know, please don't ban me Sean!] in
his truck that I just built and we installed these rockers with Poly-locks and adjusted them
twice and they are just noisy as can be. It's not the same clack you get when you loosen the
rockers up, just noisy and I can't get them to get any quieter. They are adjusting fine, so I
know it's not the lifter. Another friend of mine [also with 454] is running the same rockers
and his are noisy also. Now that I think about it, I had these same rockers on my 454 which is
the same engine I just rebuilt [Dooohh! Me have a 454? Yeah, but I was still a Poncho nut then,
just got a good deal on a Chevy with a big block] and they seemed kind of noisy also. I am
just wondering if it's a big block thing or a rocker arm thing. Can anyone give me feedback on
their experience with these rockers? Oh, and yes, I tried my damnedest to talk him into building a 455 for it, but didn't have one
to sell him as cheap as the 454 he got. He ended up spending about $3500 on this engine and it
sucks to be noisy. I could have done a 455 for him a lot cheaper. Oh, well, they'll learn
someday! I normally run full roller rockers or just the stock ones [except for the rollertips I
used on this engine back in the 80's which was the only time I used them] and don't have any
noise problems with them. What do you think Joey, Rick, anyone? Thanks! Goatman Subject: Re: [GTO] Comp cams roller tip rocker noise. Date: Wed, 4 Oct 2000 06:37:12 -0500 (CDT) From: alan fanning << Has anyone running Comp cams roller tip rockers experienced noisy operation from them? The
reason I ask is because a friend of mine has a 454 >> Yeah I run them on my 67 400 motor and have not had any problems with them at all... They're
not noisy either. Jerry Brock runs them on his 455 Tempest wagon that runs in the 12's. His are
not noisy either. ALF Subject: Re: [GTO] Comp cams roller tip rocker noise. Date: Wed, 04 Oct 2000 08:06:41 -0700 From: rickgto Paul. The experiences I've had with the stamped roller tip on BB Chevs is exactly what you're
describing. My theory (and we checked) is the sideways push the rocker gets just because of the
pushrod angle. They are not self centering and any amount of side play on the pushrod
guideplates will cause the rocker to "spin/lift”. Tap the guideplates closed so the pushrod has
little or no sideplay. The Comp rockers do not have a self aligning bucket as do others and the
tipping will actually fool the lifter into thinking it's too tight and bleed down to compensate.
The above will quiet it down quite a bit. Rick Subject: Re: [GTO] Comp cams roller tip rocker noise. Date: Wed, 4 Oct 2000 12:05:58 EDT From: Goats3 I have the Comp 1.5 roller tips on my 69 400. I thought they were a bit on the noisy side also,
so I took it back to the builder to listen to. He said” no problem". So I guess "no problem". I
think I'll try "running the rack”, so to speak, just to be sure. Kenny L Subject: Re: [GTO] Comp cams roller tip rocker noise. Date: Thu, 5 Oct 2000 01:59:31 EDT From: GoatmanPaulC << Paul. The experiences I've had with the stamped roller tip on BB Chevs is exactly what you're
describing. My theory (and we checked) is the sideways push the rocker gets just because of the
pushrod angle. They are not self centering and any amount of side play on the pushrod
guideplates will cause the rocker to "spin/lift”. Tap the guideplates closed so the pushrod has
little or no sideplay. The Comp rockers do not have a self aligning bucket as do others and the
tipping will actually fool the lifter into thinking it's too tight and bleed down to compensate.
The above will quiet it down quite a bit. Rick >> THANKS a lot, Rick! I knew you would have heard of this and have an answer. Now I can quiet this thing up so I can show him that I DO do good work! I think he was starting
to have second thoughts! Man, I just can't believe how these Chevys can be! Figures it would be
a Chevy that gives me fits! Glad I'm a Poncho Freak! Goatman Subject: [GTO] Broken Rod Question Date: Sun, 22 Oct 2000 00:10:42 -0400 From: "Bruce Jackson" Hi List! I have a 68' Camaro (please don't flame me, I restored it for my son and it has given me the
confidence to buy a 65' GTO Conv. basket case for me!) with a 400 small block. I thought the
rod on #1 cylinder broke. In examining the valve train I noticed that the rocker on the intake
valve had broken. With the car barely running it sounded like someone was banging on the engine
with a hammer (sure sign of broken rod right?), but when I pulled the head and rotated the
engine by hand, the piston went up and down without a problem. The question is, can a rod sound
like it is broken and only have a broken bolt? How can a rod be broken yet still push & pull
the piston? I need to get this damn C#*% fixed and out of my garage so I can start on the goat! Any
comments? Thanks, Bruce Jackson Swartz Creek, MI 65' GTO Conv. basket case (waiting for its' turn!) Subject: Re: [GTO] Broken Rod Question Date: Sun, 22 Oct 2000 06:48:48 -0500 From: "Dirk" Could be a bad bearing, that would keep the piston moving but the extra slop would cause a
knock sound, I heard this once in a '72 GTO that had a bad rod bearing, got rid of the sound by
pouring STP in the engine, tried driving it home only to lubricate approx. 1 mile of roadway
and the bottom of a GTO. Anybody need a vented oil pan? Its just a Chevy, put a brick on the gas pedal or push it in the nearest ditch! (just
kidding) I would replace the head, replace broken rocker and start it up and see if sound is
gone. If not time for engine R&R. Dirk Owner of former '65 GTO basket case also! Subject: Re: [GTO] Broken Rod Question Date: Sun, 22 Oct 2000 08:24:18 -0500 From: Chris Turner Had the same thing to happen on a 350 Chevy. Didn’t hurt the bottom end at all... If you
already have the engine out, pull the oilpan and look at the rod. A broken rocker will make
your engine sound like everything in it is out including the rod. You may have destroyed the
cam though. Chris Subject: Re: [GTO] Broken Rod Question Date: Sun, 22 Oct 2000 21:28:14 -0400 From: "Bruce Jackson" Dirk & Chris - Thanks for the replies! When I rotate the engine by hand I did see the lifter rise in its
bore so I don't think I wiped the cam. Is it possible that a broken intake rocker could make
that kind of sound? I really don't want to pull the engine and tranny, much less rebuild the
engine, but I don't know what could have caused the rocker to break unless the piston hit the
intake valve. When looking at the piston top I didn't see any damage and the intake valve was
closed properly and looked undamaged. Can an un-opening intake valve cause a banging sound and
make the engine undriveable? Or am I just kidding myself and really have a broken rod? Bruce Subject: Re: [GTO] Broken Rod Question Date: Sun, 22 Oct 2000 22:04:22 EDT From: GoatmanPaulC << With the car barely running it sounded like someone was banging on the engine with a hammer
(sure sign of broken rod right?), but when I pulled the head and rotated the engine by hand,
the piston went up and down without a problem. The question is, can a rod sound like it is
broken and only have a broken bolt? How can a rod be broken yet still push & pull the piston? I
need to get this damn C#*% fixed and out of my garage so I can start on the Goat! Any comments? Thanks, Bruce Jackson Swartz Creek, MI 65' GTO Conv. basket case (waiting for its' turn!). >> Look at the combustion side of the head. If the rod bearing has spun, you will be able to see
where the piston was hitting the head. Also, the piston will be shiny where it was hitting. It
may be on the other side. If the ex. valve rocker were broke, then I might say the knock you
here may be the backfire of the combustion coming back up the carb. But, it sounds like a rod
knock to me. Goatman Subject: Re: [GTO] Broken Rod Question Date: Sun, 22 Oct 2000 22:14:38 EDT From: GoatmanPaulC << Thanks for the replies! When I rotate the engine by hand I did see the lifter rise in its
bore, so I don't think I wiped the cam. Is it possible that a broken intake rocker could make
that kind of sound? I really don't want to pull the engine and tranny, much less rebuild the
engine, but I don't know what could have caused the rocker to break unless the piston hit the
intake valve. When looking at the piston top I didn't see any damage and the intake valve was
closed properly and looked undamaged. Can an un-opening intake valve cause a banging sound and
make the engine undriveable? Or am I just kidding myself and really have a broken rod? Bruce >> Bruce, a broken intake rocker will just cause a dead cylinder. A broken exhaust rocker however,
will cause all the combustion to come back out the carb since the intake is still opening and
letting fuel into that cylinder, but the exhaust won't let it out. The result is a constant
popping up the carb. If the air cleaner was on it may sound like a rod knock. Double check that
it was an intake rocker that broke and not an exhaust. Also, you may have a bad exhaust lobe on
that cylinder and all the extra pressure on the intake valve broke the rocker. Goatman Subject: Re: [GTO] Broken Rod Question Date: Sun, 22 Oct 2000 23:21:39 -0600 From: "T. H." << When looking at the piston top I didn't see any damage and the intake valve was closed
properly and looked undamaged. Can an un-opening intake valve cause a banging sound and make
the engine undriveable? Or am I just kidding myself and really have a broken rod? >> What if you got valve spring coil bind from a big cam and that snapped the rocker? Is it the
rocker that broke or the stud? If it's the stud, did you see if the rocker had cocked sideways
and cut into the stud and caused it to break? Tom Subject: Re: [GTO] Broken Rod Question Date: Mon, 23 Oct 2000 00:57:02 EDT From: DATHOE There are allot of things happening when a rocker arm breaks, I would fix the valve train and
run it, chances are there is no rod knock. When the engine is running and the piston is on the
intake stroke, and the valve isn’t opening, there is a huge vacuum being created in the
cylinder. This may create a noise. There is also a pushrod and lifter hovering somewhere in the
engine, who knows which of these things are making funny noises. Give that Chevy to a relative and on to the 65. Dave http://www.boyleworks.com/ta400/psp/rebuild455dathoe.html Subject: Re: [GTO] Broken Rod Question Date: Mon, 23 Oct 2000 08:20:40 -0500 From: Chris Turner If the valve is closed, and you was running it... I'd definitely look at the rod bearings. You
put a lot of pressure on the rod bearings. I would still take the time to pull the cam and look
at lobe. Nothing would be more disheartening than to put the engine back together and have the
knock still there or if not there this moment have it come apart on you a few miles down the
road. If you fail to plan, you plan to fail. Subject: Re: [GTO] Broken Rod Question Date: Mon, 23 Oct 2000 21:33:00 -0400 From: "Bruce Jackson" Thanks to all for your comments and suggestions. I'm afraid I'll have to pull the engine and
check further to find my problem. Damn, I had hoped to get the 65' Ragtop into the garage
sooner! It's driving me crazy having the Camaro in the garage and the GTO out behind the shed
with a tarp over her! Unfortunately, I have to get the Camaro running so I can sell it in the Spring to finance the
Goat! Bruce Jackson 65' GTO Conv. basket case ( the cute one with the blue tarp over it!) Back to TECH Subjects
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