69 l71 / l89?

[Dave B.]

Hello,
I'm new here so I hope this is the correct place to try and get some info or advice. I have owned this 69 convertible
for 20 years. Interior was already gutted except for the dash which was still intact. The engine and tranny were removed. The engine was already rebuilt and the block was decked so no numbers remained. I've been waiting to restore the car and that has now begun. The previous owner told me it was a 435HP car. It had all the correct items for that to be true such as 6500 RPM tach, single fuel line, transistor ignition and the 435 HP data plate on the console. Of course all those could have been installed after it left the factory and there is no documentation to prove it's a 435HP car. But I have found the original tags on the front springs which say EA which indicates F41 heavy duty suspension. And after researching that, HD suspension was only available on L-88 or 435HP cars. So my question is does this give me proof of a real deal 435HP car? If I take it to a NCRS judge can they verify it as a 435 HP car?

[Tim G.]

Re: 69 l71 / l89?

Dave,

I hope others will offer their opinion. The signs point to the car being a 435, but there is no way that can ever be absolutely proven. That is especially true when and if the car is restored. Have you checked for a tank sticker? You probably have, but I had to ask. I would document all the signs of this being a 435 horse car and if you want to restore the car do so. You can have the car judged as is and I'm sure the judging team could confirm that it most likely started life as a 435. If you have no paperwork and a decked motor (check for evidence of a four bolt main) be careful of completing a full restoration as you may end up upside-down from a financial standpoint.

[Dave B.]

Re: 69 l71 / l89?

Thanks for the info Tim. There was no tank in the car so no tank sticker. The block is a 4 bolt main.

[Tim G.]

Re: 69 l71 / l89?

If the rear end is original, check to see what the code is. If it's a 4.11, more evidence it's a 435. A 4.11 was only available with a solid lifter big block if it's coded FB.

[Dave B.]

Re: 69 l71 / l89?

Yes the rear end is code FB.

[James N.]

Re: 69 l71 / l89?

If the car originally sold in Canada, documentation of it's original configuration can be obtained from GM of Canada.

[Tim G.]

Re: 69 l71 / l89?

The FB rear end (dated before the build date of the car) is another big piece of evidence.

[Dave B.]

Re: 69 l71 / l89?

Thanks for the info Jim but it was originally sold in central California. I wish GM would release those records for US cars. Just think of all the frauds that could be exposed. And the real ones that could be discovered.

[Russ S.]

Re: 69 l71 / l89?

Have you tried to raise the numbers on the block the way law enforcement does on gun serial numbers?

[Danny P.]

Re: 69 l71 / l89?

Hello,
I'm new here so I hope this is the correct place to try and get some info or advice. I have owned this 69 convertible
for 20 years. Interior was already gutted except for the dash which was still intact. The engine and tranny were removed. The engine was already rebuilt and the block was decked so no numbers remained. I've been waiting to restore the car and that has now begun. The previous owner told me it was a 435HP car. It had all the correct items for that to be true such as 6500 RPM tach, single fuel line, transistor ignition and the 435 HP data plate on the console. Of course all those could have been installed after it left the factory and there is no documentation to prove it's a 435HP car. But I have found the original tags on the front springs which say EA which indicates F41 heavy duty suspension. And after researching that, HD suspension was only available on L-88 or 435HP cars. So my question is does this give me proof of a real deal 435HP car? If I take it to a NCRS judge can they verify it as a 435 HP car?

Dave you can also check the engine electrical harness if its a stock 435 harness there should be wrap tape together and the harness going to the Ti box see if anything been touch or replace

[Dave B.]

Re: 69 l71 / l89?

No I had not thought to raise the numbers on the block. Not sure where I could even have that attempted. And no I had not thought to check the engine harness, that is a good idea. I did look at it this morning and it does look original and intact with original wrap and original connector.

[James G.]

Re: 69 l71 / l89?

I have heard about raising the numbers with acid... however has anyone had any experience with the following?

I had a metallurgist tell me that if you use a thermal camera on a tripod - crank the engine let it run and get to full temp then cut it off and then take an image every few minutes through cool down that the numbers will be visible...

I have not attempted this, however he stated that "you couldn't mill enough off the deck to keep them from appearing without the deck being destroyed."