I'm trying to figure something out. From looking at my parts books I've noticed that most companies list different main bearings sets for the 88-93 Series 1 and the 94-95 Series 1. They say the 88-93 has 1/2" main cap bolts (which my 93 L67 does) and the 94-95 has smaller 7/16" bolts. I don't have a 1994+ Series 1 block around here to confirm this. I do know that the Series 2 3800 has 7/16" bolts.

If anybody has a block around that they can peak at, I would appreciate it.

Thanks,

Chris

TTT, somebody must have an old junker S1 around!

Bummer for you, the 95 motor went in the car, and the 93 is sitting here on the stand. Backwards of what you want. But I can assure you there are zero differences between the 93 and 95. 94 included.

If there are any differences in main cap bolts, it'll be only on the 92 MAYBE.

I've got a 92 L67 block that needs the bottom end torn off...

Hey Will, I'll send you an oil pan gasket and a case of beer if you check yours for me!

I am just wondering because of the problem I had getting my ARP main studs. They sent me 7/16" studs the first time even though I gave them the VIN and all the info, which didn't fit because my 93 L67 has 1/2" bolts. So they made me a set of 1/2" studs. I thought the tech I spoke with at ARP was just dumb, until I went looking for main bearings and noticed that the 94/95 listing is different and says "with 7/16 bolts".

Weird. I'd like to figure this out.

I think you're mistaken. The engine on the stand with no oil pan is a 93.

Not a 94/95.


I might be persuaded to compare the motors at my next oil change on the Zilla in a couple weeks, but my first instinct would be to suggest you don't use the ARP studs. Nobody here has ever had problems with main or rod cap bearings on the Series 1 before. I can think of better ways to use that money.

The only reason I'm using the ARP main studs and rod bolts is that the factory ones are torque-to-yield, and the ARP sets are actually cheaper than new bolts from GM (even with my 50% off). It'* not really a strength issue; I know the Series 1 bottom end can handle more than I'm going to throw at it.

My '95 L67 block is in my garage in pieces. If I can help out, let me know. Just let m eknow what exactly you want too see.

I'm wondering if you can check the size of the main bearing cap bolts for me. I'm interested to see if they're 1/2" or 7/16" bolts.

Last bump. I figured somebody here would have (or has had) a 94/95 L67 apart, but I guess not.