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Need advice on engine rebuild..

452 Views 20 Replies 8 Participants Last post by  brainfood
I am thinking about rebuilding my engine since I will have to heads off to do extensive work, and I was wondering who has done this themselves and how hard is it? also what all needs to be done to the block after it is torn apart? I know I need to get it honed I dont think I am going to overbore but if I do what else needs to be done? what is a good overbore? I have heared .039 is the max recomended but gtpro does .050 overbores I think? What pistons and other parts should I replace and what brand should I go with?
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I would recomend doing it yourself if you like that type of thing. There is a lot of hard work involved but it is not complicated. I just rebuilt my SL engine last week. It didnt get the full treatment but I replaced 1 rod, crankshaft, main bearings, rod bearings, and oil pump. I think the main question here is your goal. How much HP do you plan to run? How fast do you want to go? How many miles are on the car?

If you have the time and resources it is a very rewarding project.
I would like to run low 11's the car only has 30k on the last rebuild but I figure maybe I should put at least forged pistons and crank in... maybe not rods... I also want to get it balanced.. how would I do that if I was doing the work myself? just take all the pisonts rods and crank in and have someone do it?
If it were me, and money really wasn't that much of an option, I'd "bulletproof" my engine.

The strongest engine internals possible, HKS headgaskets, Extrude honed/ported and polished intake and exhaust, Polyurethane motor get the idea..

And I'd get a bunch of engine performance upgrades that you gotta have the engine out, or close to out, to do.

UDP, Flywheel, cams, cam gears, big turbos, DR's O2 housing/precat get the idea....
I already have most of that stuff... I am looking at getting precat eliminators though... and money is an option thats why I am doing it myself... so I already have the head work taken care of and I can get the intake ported later... but for now i need to decide what rods and pistons I should get and what else I should replace internally and also what the advantage of an overbore would be? how much more ponies?
since money is an option, I would leave it along and put that money towards mods. If you really want to do something, just replace the pistons. Since you only have 30k miles, there is nothing wrong with your rods and crankshaft. Besides you might already have a 2nd gen crank.
how would I tell if it is first or 2nd gen? the rebuild was done at a dealer and I have the reciept would that say what part number if so what is the forged part number?
Here is the part # on the crank in my car is it forged or not?
Finally Some Good News

Bryan - CAPS shows all 5-speed cranks going to that part number and all 6-speeds so it looks like you've got a forged crank afterall!
If you plan on running anymore than stock boost I would definatly go with forged pistons. They are just cheap insurance against another engine rebuild. I dont think name brand really matters unless you want to spend the big bucks. I have forged stock copies that I bought for around $500. Also go with some clevite ?SP? bearings.
What is up with everyone and upgrading the pistons... How many of you have destroyed a piston running moderate boost? I've laid my hands on 99Missles stock rod/piston that destroyed his engine... And I can tell you that it looks to me like the only damage done to the piston was from pieces of the rod, and the rod looked like a damned dounut. The piston had a coat of carbon on it but it looked in perfectly usable shape from the top. And he was running like 23 PSI at the time and NOS if I'm not mistaken. The pistons are pretty strong if you're not going too insane, but I'd definetly spend the money on a good set of rods.
What is up with everyone and upgrading the pistons...
like 357 mag said I will have them out so it is cheap insurance.. does everone suggest swain coating the piston tops? what about the rods can I get the stock rods shot peened and cryotreated? I already have a forged crank should I get this cryotreated to? what should I get done as far as labor? is it worth it to get it balanced?
VR-4_Owner: I did this at only 15psi from 15G's...91 octane, 1650F EGT's, 0.94-0.96V O2's, & lotsa timing.

I gotta admit, they did last 3 weeks in that state of tune. I did 3 highway punches straight...embarassing a LT1 Z28...until I got embarrased when my engine hung at 6000rpm because pieces of two pistons boucing around in the combustion chambers smashed the gaps closed on two of my plugs.

You need forged pistons if you plan to run 420+HP 24/7. Sooner or later something in your engine management system will screw up and you'll be glad you have forged pistons to save your butt. It doesn't take a whole lot of knock to trash a cast piston.
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Trevor, you gotta stop running that crap gas through your baby!!!!!

Man, I would never replace good pistons if I was on a budget. You still havn't said how much psi you plan to run. If you want to keep this a daily driver you are gonna have to run safe boost.
I stay away from the 91 octane now that a station opened with 93. 330,000 people in Wichita and there's one (1) gas station that has 93 octane...everything else only has 91. I drive 10.5 miles each way to keep 93 octane in both my babies.
I plan on running 20-22 psi on alcohol, 720s and a stand alone ecu, also all I can get is the crappy 91 octane around here so we have to make due... fucking california laws... it is not so much of a budget it is that I dont feel it necessary to go all out for what I am doing.. it is still a daily driver so I am keeping it from getting too extreme..
Yeah, 20-22 psi is pretty tame...:rolleyes:
Yeah, 20-22 psi is pretty tame...
:D its only a daily driver :D
I think Trevor was being sarcastic lol.

Well, I don't know what to tell you. I don't have any personal experience with 20-22psi. I know 18psi is safe and thats what my max is gonna be. You may want to go with new pistons since your gas sucks.
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