Factory Roller Cam Blocks
Thread Starter
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
Factory Roller Cam Blocks
Are all Chevy 350 blocks with 1 piece rear main seals compatible with factory roller cams?
My daughter has a 91 Chevy 3/4 ton truck with over 200,000 miles and still running. I haven't dropped the oil pan but I believe the heavy duty trucks had 4 bolt mains. If it works with a factory roller cam, I may use it for my 383 project.
My daughter has a 91 Chevy 3/4 ton truck with over 200,000 miles and still running. I haven't dropped the oil pan but I believe the heavy duty trucks had 4 bolt mains. If it works with a factory roller cam, I may use it for my 383 project.
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
Think off hand it was 87.
With today's aftermarket think you can put a roller hydrolic cam in any engine now a days....though you may have to machine the lifter bores to accept the roller lifters. Most factory roller hydrolic cams I've seen have a step in the face of the cam for a retaining plate....other old school aps have a button which extends from the timing cover to hold the cam in place. I have no idea what is in a '91 heavy duty block though.
With today's aftermarket think you can put a roller hydrolic cam in any engine now a days....though you may have to machine the lifter bores to accept the roller lifters. Most factory roller hydrolic cams I've seen have a step in the face of the cam for a retaining plate....other old school aps have a button which extends from the timing cover to hold the cam in place. I have no idea what is in a '91 heavy duty block though.
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
All the 1 pce blocks I have seen have been machined for a roller cam even if a flat tappet was fitted at the factory.Have the 3 tapped bosses in the valley for the lifter spider and the threaded holes in the front for the cam retainer plate
Race Director
Joined: Feb 2004
Posts: 12,518
Likes: 19
The 86 block was unique. It has a 1 pc rear seal, but did not have provisions for a roller cam set up. 87 and up had both 1 pc seals, and the boss' cast into the lifter valley, and for the cam retainer plate behind the timing gear.
Thread Starter
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
That's what I'm hoping. But I think Chevy continued to use flat tappet cams in many of them.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
Race Director
Joined: Sep 2003
Posts: 16,837
Likes: 338
From: Database Error Indiana
Melting Slicks
Joined: Mar 2004
Posts: 2,141
Likes: 2
From: Pittsburgh Pa
2wd trucks had 2 bolt mains and 4wd trucks had 4 bolt mains. 87 and up have provisions for roller cams but not all had roller cams. i believe up until 91 all non performance v8's were flat tappet
Thread Starter
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
Safety Car
Joined: Apr 2005
Posts: 3,624
Likes: 431
From: Dale City VA
The 1st design camshaft thrust retainer is GM PN 10088128 and is for 3.62" bolt centers.
Once you have the block apart just measure acoss the bolt pattern with a dial caliper and you'll know which one you need.
Will
Thread Starter
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
91 year model SHOULD have the narrower/smaller bolt pattern 2nd design camshaft thrust retainer. GM PN 10168501 is for 3.294" bolt centers. It is all of $8.20 on GM Parts Direct.
The 1st design camshaft thrust retainer is GM PN 10088128 and is for 3.62" bolt centers.
Once you have the block apart just measure acoss the bolt pattern with a dial caliper and you'll know which one you need.
Will
The 1st design camshaft thrust retainer is GM PN 10088128 and is for 3.62" bolt centers.
Once you have the block apart just measure acoss the bolt pattern with a dial caliper and you'll know which one you need.
Will
