SUPERCHARGE

Hey guys, some of you may remember a post I added a week ago in regards to a decision whether I should buy this 1986 corvette with a bad engine from a retired old friend I know. I'm getting it. I looked over the car for two hours with him, and figured out all its problems including the engine problem which turns out to be a spun bearing.

The car had every single option selected when he bought it (have the docs), minus the two tone paint (thank god).

Now I actually found three Engines which I'm splitting my head on. I'd like to know what you guys would go for.
1. 1986 Corvette Engine with just under 59 000 miles for 1200$
2. 1989 Corvette Engine with a tiny bit above 80 000 miles for 1700$
In both cases, they guarantee they work perfectly or i get my money back. I found some better deals but couldn't guarantee me funds back if there were problems right after the install.
3. Or this: http://www.auto123.com/en/news/car-n...p?artid=117291

I'd be inclined to go for the third one because of it's power ratings... But once it's in the vehicle, should I expect a significant amount more performance out of this engine than the stock to be worth it? Thanks.

cumbercr

The crate engine will probably not be a good match for your car. The crate is designed for a carb. The cam will not be matched to the power band of a stock TPI. You could end up with less power than advertised.

I would recommend rebuilding the engine you have. Then you'll know what you have and the components will be matched for the driving you intend to do.

VAAR

I'm new here, so take it for what it's worth, but if it's a spun bearing, I'm thinking you could replace it with a ZZ4 shortblock. While the heads are off, you can inspect the valves, and perhaps install screw-in rocker arm studs and HD valve springs. I'm thinking of doing that to my '89. The cost will be close to your option 3:

Summit Racing ZZ4 Short Block

SUPERCHARGE

I figured that, but what if I keep it carbed?.... Also, keep in mind I'll be adding headers to help breathing

cv67

That is just TOO much for a used high mile 24 yr old motor, no way.
couple hundred tops theres nothing special about an L98

Get a new one with a warranty. Spend a little more up front but never worry about it again.

SUPERCHARGE

Problem is I don't have the facilityplace to rebuild. Although I've never rebuilt, I'm figuring it'll cost a hell of a lot more if I'm going to have it done. Unless you guys can give me ideas... I may not mind paying a bit extra if i'm getting some good additional power from the rebuild than already built.

Pete K

What are your goals?
To have a fixed, nice running reliable corvette?
Or, are you looking to build a hot rod?

c4cruiser

I would avoid any used engine. While a seller may guarantee they "work perfectly", the chances are that labor is not included.

You didn't mention if the engine currently in the car you are getting has iron or aluminum heads. Same with the '86 used engine. Aluminum heads were on all '86 convertibles and late production coupes.

The GMPP engine would be my choice (or the ZZ4 motor) but GM includes a carb setup. You could sell the intake, carb, air filter assembly, and the chrome valve covers to help offset the costs.

Also look at the various GM shortblock assemblies they offer. You can simply remove the heads from the existing engine and have them pressure tested and a truing of the surfaces and bolt them on to a new short block. If you go with a ZZ4 short block, consider going with a set of performance aluminum heads that will accept the L98 intake manifold.

Also look at Summit Racing for their selection of GM crate motors and the other brands they offer. They do ship to Canada but you will most likely have to pay any duty and shipping costs.

cv67

Browse Pace Performance Parts also they sell TONS of different variations of GM crate motors with warranties. This is the route Id go without room and experience to rebuild...not to mention most rebuilders out there do crap work anyway.

l98tpi

This is probably a better route to take. Purchase the short block and use your existing components. You have to work through compatability issues with car ecm and engine ecm when you go with a different set up.

Muffin

Rebuild what you have. Likely the least costly option and you keep the numbers matching. Matching numbers will not mean squat for many years if ever but will be a nice conversation topic.

Why ever on earth would you want a carb?

SUPERCHARGE

Ok, thanks peeps, these are the type of suggestions I'm looking for. And this 86 was the later model with Aluminum heads.

I'll look into Summit racing, I've browsed their site before. And if shipping for a crate engine or others parts turns out to be too much, I'll see if I can simply pick it up from the U.S somewhere. I'm near several borders.

And my goal for those who asked is to simply give the car a good boost without turning it into a hot road. Come on, L98 engines were obviously not very strong for 5.7's

cv67

Most of its due to the crappy intake and exhaust manifolds they have.
Think GM sells a crate that uses a Vortec head, you can get a Vortec base also for your TPI that will pick it up some.
IF youre going carbed your opitons for power really open up.

mtwoolford

a ZZ4 shortblock is a very robust piece; there are ton's of buildups in various hot rod magazines that attest to this fact....but it's not going to be inexpensive.

first the ZZ4 shortblock is pricey (IMHO)

second it comes without cam or valve train; this isn't as bad as it sounds because you will need to intall a cam to maximize your TPIS intakes potential...and I'm told that there are many to choose from, some of which offer significant improvement over the (25 year old) factory offering.

third is the issue of the heads...invest money in the original heads or upgrade to late (aftermarket) and vastly improved heads from AFR, Edelbrock, Twisted Flow, Dart or others ? Deduct the amount of money you'd spend rehabing the original heads, and a new set of heads may not be all that more expensive.

On the plus side, you already have a donor engine which can provide all the intake, accessories, and (assuming the original engine has a one piece rear seal) the corvette specific oil pan, flywheel/flexplate, etc., necessary to complete your build.

The crate engine you're looking at is a great bargain, and probably the most bang for the buck. But, you'll need to ditch the intake manifold and oil pan (its too deep for the corvette chassis) and I assume that you original engine has a one piece oil seal (1986 seems to have been the change over year...but you never know till you look)

good luck, with a little work you can certainly come up with a combo that offers some, and maybe significant, improvement over stock

steven mack

If your going to use a crate motor I would go with the GMPP ZZ4 with the fast burn heads.You get a great TPI motor with Plenty of horsepower and torque 400/400 and a guarantee.Can't go wrong there.

-js-

My late 86 was a non roller equipped block and is a one peice rear main seal.
Note that the early non roller blocks would have an extra cost due to the need for aftermarket roller lifters with the bar verses the factory setup if a roller cam is a must have.
87 and up L98s have the factory roller setup.

mtwoolford

Unless you're doing a period correct restoration, I would avoid putting money into any small block that does not have a factory roller setup. The literature is replete with horror stories about the removal of zinc additives from motor oils and the subsequent failure rates of flat tappet cam lobes which depended on the zinc....roller cam retro fits are available, but they are VERY pricey...it would be cheaper to purchase a roller block (new or used) and transfer your engines rotating assembly into it.

again, I would suggest getting a long or short block with a warranty and going from there. It'll certainly be simpler...and probably cheaper in the long run.

I would avoid (not all) used engines..but certainly the two you have mentioned. Too old, too many miles, and seriously, when was the last time either of them ran ? Unless you intend to go through them; but then, you might as well rebuild your present engine, which apparently is not something you want to do.

p.s. Chevy now sells (for god only knows how many $$$) a "super" ZZ4 crate engine with AFR heads that makes 464 horsepower, Now that's inspirational.

cv67

There ya go, new with a factory warranty cant complain.

Always built my own but its hardly worth it anymore unless its a "gotta be this way" piece. Even the current one Im having done for once just not worth it anymore. Outside of some portwork and block prep its someone elese baby this time. Seems these days GM is putting out some nice pieces that are competitively priced some with half decent pieces in them.

Burn up your plastic, turn the key and go!

Benny42

Any later model 350 roller short block will be a good upgrade. Way more cam choices & no
"low zinc oil" issues.