I am planning on rebuilding my 87 L98 in December. I am probably going to replace the pistons, rods, etc... What compression ratio would you go with on aluminum heads? Someone told me 10.5 is the max.

How much of a restriction am I looking at on the cam when I replace it? I have a hypertech chip, but I dont know how much of a cam change I can go with.

Is there anything that can be done to the intake to improve it?

How much does porting and polishing the heads increase hp/torque, how much is it, and where would you get it done?

Thanks in advance!


[Modified by amswak, 9:59 PM 9/24/2003]

 

What's wrong with it currently? What are the plans for the car? Daily driver? Drag racer? Road racer? A combo of them?
What kind of fuel do ya plan on using? That should help ballpark your C/R
Do you have emissions tests to worry about? The hyper ain't too different from stock, so some room there.
Anything to improve the intake? The stock TPI? Uhh....yeah, get rid of it :D
Actually if you want to put in a bunch of sweat and hours on them for a few moew 100 useable RPM, you can siamese them at their bases.
porting the heads can be good if ya find the right pair of hands to massage those tracts. Let us know what ya decide.

 

What's wrong with it currently? Bad head gasket and bad compression ring

What are the plans for the car? Daily driver? Drag racer? Road racer? A combo of them? Combo of them till I graduate, then eventually a project car

What kind of fuel do ya plan on using? 93 octane

Do you have emissions tests to worry about? Nope, everyone here is determined to suffocate in traffic I think

Anything to improve the intake? The stock TPI? Yeah its stock with SLP intake runners....how much am I looking at for better intake?

what do you mean by siamese them at their bases?

Where can I get the Heads ported, for how much, and about how much does it help?

 

The 87 heads are ok, not the greatest but ok. Probably good until 300-325hp. So unless youre thinking of 350+hp, then you dont have to change those.
Porting should add about 20 to those original numbers, i figure, maybe more maybe less. Porting them though, wouldnt be worth it. It'd cost you the same or more to get the porting as it would the later heads, probably much more.

Any engine shop with a CNC machine can do it.

If you do want that kinda power, then keep an eye on ebay to get some 88-91 vette heads, casting number 113. They support 350hp untouched, and probably around 400 ported. If we're talking a 400+hp beast, then the AFR 190-195s are best, airflowresearch.com.

Use the Clevite bearings, a cast crank is fine, but if you want to have the bottom last almost forever when you do top-end stuff, it might be a good idea to get forged pistons and rods. (JE, Speedpro, Ross, etc.)
Put in a Melling Oil Pump, I use M55-A.

You need to decide how you want your power before going a certain route. If you want it to look like the intake you have now, you can look at Joe90 and Vic'89 's setups, run a search. Basically portwork of the stock components and replacement of some with better aftermarket parts.

If you want super low-end and great midrange and good top-end, go Superram. (lingenfelter.com) I'm for the SR.
If you have a stick-shift, Id look into the Miniram, because it'll make its power at midrange and high rpm. (tpis.com)
SR's rec. cam is the 74219, MR can go from something like the ZZ9 to something outrageous.

The Stealthram needs a custom plenum made to fit under the hood, there is a guy here who does it, grumpyvette. I dont know what cam is rec for it.

Any cam that has specs far from stock 202/206 @050" will need a custom chip burned. There are guys here who do it, or try fastchip.com. That Hypercrap is worthless.

CR, i wouldnt go above 10.5:1. You have to pick a piston for the cc of the heads, just figure out which head route you wanna go.

Do run searches on Superram, Miniram, Stealthram, stuff and youll learn alot.

 

Just curious,

How much HP would someone be expecting to gaing with a SR and 219 Cam.

Aprox?

Any one here with a SR and 219 cam setup? no head work and normal exaust , maybe just a catback? and had his car on a dyno?

 

Ive already told you before. READ and talk to Scorp, Ralph, Beach Bum.

 

Spend your money, no place else, on machine work. Quality machine work is everything. Make sure the shop is experienced, clean, and willing to spend time with you. And make them commit, in writing, to a time frame and a cost estimate. You'll thank yourself later.

Also, stop in periodically and check on the progress of the block, crank, rods, etc. Be as hands on as possible. If they try to hide from you, or keep you at a distance, this could be a red flag.

 

So... Scorp, Ralph, Beach Bum

Thanks Vader, I'll Instant message those guys and see if there willing to answer a bit of my questions and see what they did with that SR and 219 cam and how they got it all bolted up and stuff...

I think the first time you told me there names... I didn't notice... :yawn: I must of been asleep that day or something.

Ps: I'm always reading "trust me" I've learned more about cars in the past 3 months then I did in my hole life.