BowtieBoyAV

OK guys, I have a pretty specific question here and am looking for experience based opinions.

First a little background.
I am doing a rebuild for my friend on his '98 (I know one of the dreaded years) LS1. Block and most of the internals are completely stock. It started with him having a leaky head gasket, he didnt have time to mess with it so he brought it to me. I pulled the head that was leaking and found the liners scratched up a fair amount. Pulled the other head, same scratches. Decided it was bad enough to warrant a rehone/pistons/rings. Engine is out and now I am at a sticking point after having done some additional research.

Shortly after his upgrades (listed below) he suffered a pretty bad overheat when the water pump went out that blew both his head gaskets. He replaced them with another set of Fel-Pros, but didnt catch the liner scratches at the time (assuming the overheat is what did it).

Here is engine mod list.
SLP Cold Air & lid
FAST Manifold 78mm, stock throttle body
Dart 205 heads w/ 2.02 valves
Comp 222/224 @. 050" 112LSA cam (.600/601 lift with 1.8 rocker ratio)
1.8 ratio Harland-Sharp Al Roller Rockers
Comp pushrods
1 7/8 Hooker Long Tubes
3" Y-Pipe (no cats)
3" Flowmaster system
Underdrive pulley set
MSD Blaster coils

I talked to the guys at ERL and I am worried about the power levels with this early rev block.
I have also learned that GM switched from the crappy composite graphite gaskets (which he originally had) to an MLS style head gasket.

My problem is I dont know for sure what cased the 2nd set of head gaskets to leak. The failure was only on the block side of the gasket b/c there were soot trails on the deck and the gasket was messed up. Is it possibly from bore deformation or was it a mismatch of the older style GM deck's poor surface roughness and the steel shim style Fel-Pro we used previously? He also reused the head bolts the second time around...I believe that shouldnt have been an issue.

So...if I have it rehoned to 3.905, resurface (mirco-polish) the deck and head to a low Ra value, and switch to the later style GM MLS head gasket, put new pistons and rings in it, is it just going to develop another leak?
Also, how many times can I safely re-use a set of ARP head bolts?

I really really really dont want it to develop a leak again since I dont want to have to help him drop the sub-frame and pull the engine again. He hasnt been able to drive the car much over the past couple years, so it needs to be reliable so he can enjoy it as a daily driver.

Sorry for the long post.
Thanks for the input!

99SSAGUI

iTrader: (7)

If the bolts are ARP than the fact that he re-use them is not big deal if he reused the stock bolts then that could be it since they are torque to yield bolts. I know that not all stock heads can use the MLS head gaskets since there is a notch on the earlier heads that requires the old composite graphite gaskets. If he is using the Dart heads this should not be a problem (I don't think anyway) but check the heads just in case (the notch will be on the chamber side of the head opposite to the valley side). Resurface with a lower RA value is only needed when using cometic gaskets since they are coated with a viton coat so if you are using GM MLS gaskets or felpro gaskets I don't see a problem with that either. I will check the bores for any deformation (if you have the equipment) or have a machine shop check it, before proceeding with any more work.

I would think that maybe there was a problem with the fist set of gaskets, I will do a research on the previous gaskets and see if they required a better surface. hopefully someone with more experience will chime in. Good luck!

BowtieBoyAV

Thanks for the input. Yea, he did not reuse the stock bolts, so no worries there. And the Dart heads have been on it all along, so that should be OK as well. I will double check though on that relief you mentioned. And I planned to have a machine shop check the cylinder straightness as well. Seems like we are on the same page.

Is there a distinct advantage to running the cometic gaskets over the factory GM MLS one?

Anyone else have any comment on the power limits of the 97-98 blocks?

I saw just tonight in another post that somebody was running a stroker on a 98 block with 3.903 bores. Makes me think it will be OK, just looking for some additional reassurance. Thanks.