L89 HELP

[Howard K.]

I would really appreciate some help from the L89 section especially 1968. If any of you are very knowledgable in this area please let me know differences from the standard 435hp and the L89 other than aluminum heads. Or at least some tell-tell signs that its a real car instead of a made car. THANKS

[Dick W.]

Re: L89 HELP

The only difference is the cylinder heads and the suffix code on the pad. Same block, pistons, intake, carbs, exhaust manifolds, etc.

[Joel Falk]

Re: L89 HELP

Does the car have a POP, tank sticker, or other documentation?

[Howard K.]

Re: L89 HELP

Tank sticker

[Warren F.]

Re: L89 HELP

Glen,

The only other choice is to remove the heads and see if the date code on them, corresponds to the correct time frame for the car. I would suspect it to be damn difficult to find a properly dated set of heads for that particular build date on the car.

[Ronnie Rains]

Re: L89 HELP

68 heads are available if you have the $$$ I would not rely on head date as this is easily over come. The tank sticker will tell you ( if it is real) I have a 68 L89 correct in every way but no doc.'s There simply isn't any difference with the 435's.

RDR

[Steve Wallach]

Re: L89 HELP

I don't think you would need to remove the heads, just the valve covers. My L71, the casting dates of the heads are visible with the valve covers removed.

Tank Sticker, POP, Window Sticker, Sales Order etc. may be the only way to truly tell. Do you have any owner history? Written statements from previous owners all the way back would help also.

Steve

[Warren F.]

Re: L89 HELP

Yes, factory documents, such as Corvette Order Copy, Car Shippers sheet, Window invoice, Protecto plate w/pamphlet is certainly the absolute best verification for whether the car was originally factory assembled as an L71/89 optioned Corvette.
However, without this paperwork for proof, these properly dated heads would be your only other method to try and establish the possiblilty of originality.

[Warren F.]

Re: L89 HELP

Factory aluminum big block heads have casting dates on bottom side. Casting numbers are on top side.

[Wayne M.]

L88/89 Aluminum Head cast dates (underside)

As Warren has indicated. Here's a set of 842's off an early '68.

[Steve Wallach]

Re: L88/89 Aluminum Head cast dates (underside)

Removing the heads would be worth doing, but it would take me a at least a weekend to remove the heads and put them back on. Good weekend project though.

Steve

[Wayne M.]

Don't have to remove heads -- only intake

as the cast dates are on the inlet runners of the head. Just use a mirror once you take the intake manifold off.

[Jean C.]

Re: L89 HELP

I guess that any car can be made up, but having an original tank sticker should avoid a problem.

At the Corvette/Chevy Expo in Houston over the past weekend, a '68 BB convertible in Corvette Bronze/Dark Orange caught my eye as I have the same car. A cursory examination revealed that it had fresh paint/seats/carpet, L89 aluminum heads (w/ snowflakes), air pump with all plumbing, factory A/C with correct date compressor, low red-line tach and absolutely no A/C controls on the console. Go figure. Quite a mixture for what appeared to be a "built" L89! The fact that there were no A/C controls indicated that perhaps the console (and dash?) had been replaced. I didn't look any further to see what else may have be out of the ordinary. Sorry, did not get the VIN. Car was there only to have an Al Knoch top installed during the show.

If this car appears "For Sale", it could be trouble.

Best regards,
Charlie

[Howard K.]

THANKS EVERYONE

The heads are the correct build date for the car and it does have a corresponding tank sticker. I am just paranoid these days