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all tpi...self align rockers?

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Old Jan 15, 2008 | 04:35 PM
  #1  
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Car: 87 GTA
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all tpi...self align rockers?

Ive read on searches that 87 and earlier motors( mine is an 87 tpi 305) used non self aligning rockers, that the push rod holes in the heads are oval for regs and guide plates for aluminum. I also read an article that said all tpi motors have self aligning rocker arms. Any way Im looking to get 1.6 rollers of the classified section and I want to make sure I get the right set up. So do I need sa rockers or can I get regular rockers. thanks for any info.
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Old Jan 20, 2008 | 08:56 AM
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Re: all tpi...self align rockers?

I've found the statement that all newer tpi heads require SA rockers is kinda misleading. I've got a set of 083 casting L98 heads from an 88 tpi 350 motor that have the old style pushrod slots, and according to popular myth, it should have the big, round pushrod holes that require SA type rocker arms. Best advice is to pull a valve cover and look at your pushrod slots. If they're narrow and sorta rectangular shaped, you can run non-SA rockers, if they're big and round, and don't come close to touching the pushrods, you'll need to use SA type rockers. In fact, here's a pic of SA type pushrod holes.

Last edited by Pat Hall; May 20, 2008 at 01:52 AM.
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Old Jan 22, 2008 | 09:37 AM
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From: chicago
Car: 87 GTA
Engine: 385 sbc
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Re: all tpi...self align rockers?

thanks man , really appreciate the pic.
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Old Jan 22, 2008 | 09:49 AM
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From: huntsville, al
Car: 89 IROC
Engine: 6.8 HSR N2O
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Re: all tpi...self align rockers?

My 89 L98 has SA rockers and "old style" slots in the heads. I used SA 1.6's and have no problems.
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Old Jan 23, 2008 | 04:10 AM
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Re: all tpi...self align rockers?

Originally Posted by antman89iroc
My 89 L98 has SA rockers and "old style" slots in the heads. I used SA 1.6's and have no problems.
I'm sure that works fine too. I just wanted to point out that he'd be ok running non-SA type rockers if he does happen to have the old style slots. I'm starting to wonder if it was mainly the 305 heads(081 casting) that had the big pushrod holes in those years. In fact, that pic I posted is of an 081 head.
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Old Jan 23, 2008 | 08:30 AM
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From: huntsville, al
Car: 89 IROC
Engine: 6.8 HSR N2O
Transmission: TKO 600
Axle/Gears: 9" Moser 3.50 True trac
Re: all tpi...self align rockers?

Interesting. Would have saved me a bunch of money. However there's another consideration. I believe that part of the reason for the SA rockers is that they're narrow body to clear the center bolt valve covers. Maybe they don't need to be self aligning as much as narrow body. FWIW.
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Old Jan 23, 2008 | 09:46 AM
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Re: all tpi...self align rockers?

Well good luck getting any standard roller rockers to clear the stock vavle covers. You can pay the extra money(I didn't) for Crane cams rr that are clearanced for the stock valve cover's or just get a set of new valve covers or try to modify the stock ones.

Just a thought most of the cars that have more miles may have valve covers in poor shape anyways.
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Old Jan 24, 2008 | 01:58 AM
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Re: all tpi...self align rockers?

Originally Posted by antman89iroc
Interesting. Would have saved me a bunch of money. However there's another consideration. I believe that part of the reason for the SA rockers is that they're narrow body to clear the center bolt valve covers. Maybe they don't need to be self aligning as much as narrow body. FWIW.
Agreed. Yeah, you can either trim the bolt braces on the stock covers or use aftermarket ones to work with standard width rr's. Otherwise, you have to use the narrow ones. I bought a set of taller, aftermarket, aluminum covers a while back from a member here. They clear the standard width, non-SA rr's just fine. The pushrod slots are a non-issue now anyways since I've picked up a set of AFR heads w/guideplates that are going on the motor this spring.
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Old Jan 24, 2008 | 07:34 AM
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From: huntsville, al
Car: 89 IROC
Engine: 6.8 HSR N2O
Transmission: TKO 600
Axle/Gears: 9" Moser 3.50 True trac
Re: all tpi...self align rockers?

Originally Posted by Pat Hall
The pushrod slots are a non-issue now anyways since I've picked up a set of AFR heads w/guideplates that are going on the motor this spring.
Cheater! I'm jealous.
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Old Jan 25, 2008 | 09:08 AM
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Re: all tpi...self align rockers?

Originally Posted by shocker89bird
Well good luck getting any standard roller rockers to clear the stock vavle covers. You can pay the extra money(I didn't) for Crane cams rr that are clearanced for the stock valve cover's or just get a set of new valve covers or try to modify the stock ones.

Just a thought most of the cars that have more miles may have valve covers in poor shape anyways.

Standard Com Pro Mags fit fine under the stock valve covers. You just have to remove the baffels. 5 second job.
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Old Jan 26, 2008 | 01:33 AM
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Re: all tpi...self align rockers?

Totally agree dude. I only paid like $50 for the nice aftermarket covers, and they clear standard ones just fine. Since my L98 heads had the narrow pushrod holes anyways, and now that I have AFR's with guideplates, I'm really glad I didn't fork out the extra cash for the Crane narrow bodied, SA rockers. Besides that, your money is definitely better spent on a set of the Comp Pro Mags. Why pay almost the same amount for for softer, aluminum rockers that are way more prone to fatigue. Stainless steel, full rollers are the ticket these days, especially on a street driven car where durability is an important factor. I'm running Harland Sharp aluminum rr's on my 69 Camaro's motor, but it only sees about 1K miles a year, if that, since it's just a weekend play toy. Besides that, I bought the rr's for that engine probably about 15 years ago, when the stainless ones were uncommon and cost mega-$$$.
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Old Jan 26, 2008 | 01:31 PM
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From: chicago
Car: 87 GTA
Engine: 385 sbc
Transmission: 700r4
Axle/Gears: 2.73 posi
Re: all tpi...self align rockers?

So if in fact i do have the oval shaped hole, do I need guide plates or just let them rub on the head.thanks
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Old Jan 26, 2008 | 01:48 PM
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Re: all tpi...self align rockers?

Originally Posted by Mkos1980
Standard Com Pro Mags fit fine under the stock valve covers. You just have to remove the baffels. 5 second job.
Exactly correct, but you should have read the entire post. The original poster was asking about aftermarket "rocker arms" which, of course, includes Pro Mags. We all know those aluminum things are actually door stops, since they certainly aren't what any self-respecting engine builder would use as a rocker arm. The Pro Mags do fit the stock cover bolts nicely.

As for the guides, the push rods are going to rub on something, be it the head opening or a guide plate. If you open up the head guides, you can choose between SA or plates.
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