i've been considering what to do with the c3 since i blew the motor a few months ago. now, if money were no object, i'd already have a killer stroker motor and be burning rubber down the road. as is the case with most of us though, money very much is an object of which i have too little. not to mention time, or the lack thereof.
so here's the dilema.
a couple weeks ago i found an ad in the local paper for an L98 from an '88 corvette for sale. the vette was totaled but the engine is advertised as being unhurt internally. the guy wanted to sell it complete with the 4L60E tranny for $1500 but i told him i have no interest in an auto so he said he would take $1k for the motor. i (tenatively) agreed providing he included the rear spring.
now i'm conflicted. the engine has somewhere around 100k miles on it so at least it could use a fresh set of bearings and probably valve seals. but i'm concerned about the potential internal damage it could have sustained. there was a slight ding in one of the intake runners, the right side header needs to be replaced and the crank pulley has a dent in it. additionally, the flange on the trans that the torque arm bolts to is broken as is the flange on the diff, indicating the thing took a pretty hard smack. the donor car is sitting right next to the engine so i can tell you it is undoubtably a corvette motor and also it was one hell of an impact.
as i see it:
pros:
aluminum heads
one piece rear main
roller cam/block
cons:
may still need overhauling
no guarantee the internals aren't completely destroyed
still have to convert the engine to carburation <OR> get a stand-alone TPI controller
need a new style flywheel since the old flywheel and new crank are not interchangeable
on the other hand, i could take the same amount of money and reinvest it into the original engine and get the same amount of power but with newer machine work and better components.
i'd like the L98 simply for the aluminum heads and roller block but which is the best way to go?

 

I vote for rebuilding what you have. $1000 goes a long way on a small block.

JIM

 

Rebuild the L81. Be a lot less problems down the road.

 

dont forget to add in the cost of a manifold and carb to the l-98..lots more bucks to rebuild the "98" and get it right for your car,,versus a "nice" rebuild for your car.

 

thought i would just re-use my original carb and bowtie intake until i picked up a non-computer carb later. even so, i think there's going to be a lot of detail work to put the L98 into the 81.
so far, i'm with you guys.
one thing i was thinking about with the L98 is i could probably take off the TPI system and sell or trade it for a good carb. just a consideration.
i'd like to hear from any of you pro-L98 people.

 

use L-98 heads on your existing block.

Are you still going to track the car? You have to be careful about making too many mods to kick you up to a prepared class.

There's nothing that different about a L-98 except the al heads and they don't breathe that good. I use them for the weight savings.

 

Put the L98 in. I have 2 of them and love them. Do a search on my user name and TPI in the last week, I posted my C3 TPI 'Primer". You can put it in the car with the late accessories pretty cheap.

As far as damage to the engine, I doubt it. The donor car the engine in my 69 came from was hit so hard in the side it broke the bellhousing off the 700R4. Get a new crank pulley and you should be fine.

 

Do the L-98.

Even if you only run the stock EFI on it, it'll make good power, get great mileage and be dead-on reliable for a very, VERY long time...

So what if you have to re-ring it? The aftermarket goodies that you'll be able to install on the L-98 in the future, will far outclass what you've got currently- you're looking (IIRC) about 380 HP, from pump-gas, and very docile street manners... And STILL have good gas mileage.

The wonders of EFI never cease to amaze me...

 

A few more things:
It is very common to break the tailhousing on an automatic when a C4 wrecks. An 88 has a 700R4 not a 4L60E (or a 4L60).

If you get a complete C4 engine it will go right in. You can use the C4 exhaust manifolds, they have 2 1/2"outlets. It is a little tight against the steering idler on the passenger side, but a good exhaust guy can make it work fine. C4 accessories work out nicely in a C3, get an air pump eliminator from Breathless or Dragons Breath. I like the 84-85 alternator better than the 86 up. It plugs right into 69-82 harness. You can do that when you order the airpump eliminator, just get ane for an 85; the lower alternator bracket is the same 84-91.

If you have a complete C4 engine you just need a harness, ECM and PROM, fuel pump, and change to fuel-injection hose. One final note, you can't use a water-pump mounted fan on the C4 aluminum water pump. It is reverse rotation and not meant for a fan. You will have to add an electric fan if you use the C4 accessories. Either C4 alternator should be enough to power this. If you have an ammeter car, it may not handle the extra amperage and have to be bypassed. Voltmeter cars may need a heavier/additional wire from the alternator to starter.