I am buying a 1992 Z-28 25th anniversary with an L98. Does anyone know if that is a 2 or 4 bolt main. I am building a 383 stroker that will put out about 500 hp and 450 ft. lbs. of torque before the bottle. And I am putting either a 200 or 250 shot on it on top of that. I already have everything except the block and was wondering if I could use the same block. I know that the hp and torque I will be making is too much for a 2 bolt block to handle. If you know, please enlighten me. Thanks.

if it's stock 2 bolt, one piece rear seal. good luck
shaggy

Don't worry about it. The block is the same, regardless of which caps the factory installed in it. You can create a much stronger assembly than a factory 4-bolt block, by using aftermarket main caps with splayed bolts.

That sucks. I am having a little difficulty finding a 4 bolt. From what I hear, they are hard to come by nowadays. I found a core yard, that has them, guaranteed rebuildable for $250. BUT, I am very skeptical of buying a block from a core yard, and I don't have the money to buy a $2000.00 block from Summit. I guess I will post up in the parts wanted section. I was unaware that the L98's were a one piece rear main. Thanks for your help.

The crank I bought, is a SCAT 4340 forged stroker crank, for a two piece rear main. But thanks.

Same advice, different core.

Bcoop,

Welcome Aboard!

Since you're apparently relatively new to the boards, I'd like to point out the SEARCH feature linked to the pages (in the upper right quadrant of the page). There is an invaluable archive of information and experience scattered among the million + posts in the archives.

If you perform a casual search, you'll likely discover that RB consistently offers excellent advice and information. He is not alone. There are thousands of skilled, experienced, and gifted members here. I hope you can add to that total. I'm sure you have experiences and ideas to offer.

Basically, what RB is indicating is that a "rebuildable" factory 4-bolt case is generally weaker than a converted 2-bolt case. That "rebuildable" case may be rebuildable only by sleeving a bore, which is almost never desireable. A good 2-bolt case can be the basis for a very strong rotating assembly through the purchase of $100 worth of 4-bolt splayed outer bolt conversion caps, and the $200 in align boring labor at your machine shop. Align honing labor can cost even less if you are prepared to deal with a custom length timing set.

So, for about $50 more than that "rebuildable" core alone, you can have a ready-to-go four-bolt case that is typically stronger than the factory version. You'd probably have $50 in labor just to clean up the mains on the core, so you can make the call. Save the extra cash for a really good crankshaft if you're going to spray it.

Vader, I don't have much experience to offer. This is my first f-body car, as well as my first high number motor. But I'm sure that after this complete rebuild, I will have more to offer. I have another question. The crank is for a two piece rear main seal. So, can I or can I not use the same block. The way I had understood it was that I can not use the same block. Am I correct in that? Also, I did a little research before buying the motor components, and I was told by several people that the 4340 forged steel crank, was the best you can get without going up a step and paying major money for a forged aluminum crank. What is your opinion on that. I figured that it would be strong enough to hold the spray, if I am wrong, PLEASE let me know before I put this beast together.

You are correct, you cannot use that crank in that block. You need to either get a crank for a 1-piece RMS block, or get an earlier model block. There's no particular advantage to either approach, except that there are no earlier-model blocks with the factory roller ssetup; so if you plan on using that, you need to get the right crank. Alternatively you could use a "retroift" roller setup in an early block. Hard to say which one would be cheaper or easier.

Cranks are never made of aluminum. The one you have should be OK for what you're talking about doing, as far as that goes.

crank is 4340 forged SCAT. 6.0" SCAT rods, I bought a new kit from Trick Flow which included: Double Roller Timing Chain set, 1.5 Roller Rockers, 23 degree twisted wedge aluminum heads, trick flow cam- 246/254 @ .050 lift .558 intake/.558 exhaust 72cc combustion chambers, 195 cc intake port. Edelbrock Victor Jr. intake, Holley 750 cfm dp mech. secondaries, oh yeah, the pistons are also made by Trick Flow designed for use with these heads. oh, and the cam is a roller cam, I'll probably use the Lunati Roller Lifters. Heads will be fully ported, intake port-matched, and gasket matched of course. If I am leaving anything out, feel free to ask. I need all of the experienced advice I can get

O.k, I must have mistaken them, but I remember them saying there was a step up that was EXTREMELY expensive. I could still exchange my rotating assembly for a one piece crank. I guess I should do that. Thanks. Your suggestions have been taken into consideration.

It was probably to that one they have that's forged by 10,000 year old slave gnomes in the fiery furnaces of Hell out of 99% pure virgin nonobtainium, alloyed with a pinch of irreplacium for extra sheen.

Seriously, if you're already buying lifters, then don't worry about getting a later model block, or a 4-bolt one; just get a regular 2-bolt one, make sure it doesn't have The Problem (where the starter bolt holes are too far from the crank) or The Other Problem (where one or more lifter bores don't point perfectly straight at the cam), and add the splayed caps from Milodon or Callies or Oliver or whoever. You'll end up with a far stronger finished product, for probably very little more money than a factory 4-bolt block will run you.

I should have known that SMARTA@@!!!! No, that was funny though.

Yeah, most will tell you that I'll usually support RB, but I think even he has exaggerated this time.

If you research it, you'll find that they weren't truly slave gnomes, but were minimally compensated for their efforts by Cathy Lee-Crosby. You'll also discover through careful metallurgical analysis that it wasn't even purely a Chinesium/Irreplacium alloy, but cheap knock-off Taiwainium/Chinesium alloy that was tainted with unobtanium, and simply misrepresented by the sales person.

C'mon, RB. Quit misleading the new guys...