Early vs. late 1969

[Bill Stephens]

I need to replace the air dam and radiator support to radiator cushions on my 1969. The catalogs call for different parts based on whether the car was early or late. Unfortunately a lot of these parts were missing when I took it apart, which probably accounts for why the car ran fairly hot.

The relevant digits at the end of my serial number are S732199, which I think makes it almost the 33,000th Corvette produced that year. If that's right, I'm pretty certain that this is a late-production vehicle, but I'd like to get something definitive before starting to order parts. I'd appreciate any advice anyone can give me. Thanks.

[Dick W.]

Re: Early vs. late 1969

I think that you would be safe with the assumption of it being considered a late car

[Robert S.]

Re: Early vs. late 1969

I agree with Dick, given they made 22,149 coupes and 16,633 convertibles in 69

[Bill Stephens]

Re: Early vs. late 1969

Thanks. That's what I thought, but I didn't want to go through the hassle of having to exchange the parts because I mis-read the VIN.

[Joe L.]

Re: Early vs. late 1969

Bill-----

You didn't mention what engine and radiator that you have. 300 hp with manual trans, some 350 hp, and L-88 with manual trans used round radiator-to-radiator support cushions of GM #3786786. All other applications used "stirrup-type" radiator brackets with "rectangular" insulators of GM #3886891. With respect to these cushions/insulators, there was absolutely no difference during the 1969 model year.

With respect to the upper air dam, there were differences. I can tell you, for certain, that my original owner, late 1969, built mid-September, 1969, small block had the "3 piece" air dam. If your car is a small block, then I strongly suspect that it was originally equipped with the same. If it's a big block, I would strongly suspect that it was originally equipped with the "1 piece" "long" design air dam.

I realize that the above air dam information is at odds with the JG. So, I think that we may need to revise that information in the next edition.

[Bill Stephens]

Re: Early vs. late 1969

Thanks Joe. It's a 350/300 with an automatic. It doesn't have the original fan shroud and most of the cushions/air dam pieces that should have been there weren't when I took it apart because the support was rotted out. It always ran a little hot before I took out the radiator, and I suspect it was because of the missing pieces.

I think you're right about the three-piece air dam, and that's what I'm going to order. I've redone a fair amount on this car, and this radiator/support/fan shroud configuration is the most confusing thing I've run into. I think I've got it now. Thanks again.

[Joe L.]

Re: Early vs. late 1969

Bill-----

A 1969 350 with automatic trans uses a copper/brass radiator with the "stirrup"-type mounts, top and bottom. It also uses plastic fan shroud GM #3956109.

[Bill Stephens]

Re: Early vs. late 1969

Joe,

Here's a follow-up question for you. I finally thought I'd tracked everything down correctly, but the radiator support I received was wrong. It is identical to the one in the car, but the fan shroud mounting bolts are farther apart. When I looked more closely, mine has the passenger-side bolt inset a couple of inches to accommodate the automatic transmission cooling lines. I called the place I bought it and they said mine is correct, so I went to a near-by corvette shop and was told that this was pretty common and I needed to modify the one I got.

Does that seem like the right advice to you? I can't find anyone who differentiates between the two I have right now. I don't mind modifying it, but I'd rather just get the right one. Any insight you can offer would be greatly appreciated.

[Chris Patrick]

Re: Early vs. late 1969

At the price you pay for a reproduction support, you shouldn't be having to move mounting bolts yourself to have the shroud fit, unless they told you up front they did not make your model but had one close.

Is this a Coffman support? I have found them to be very accurate in the past and also most helpful with any issues.

Unless you are confident you can do the work yourself and make it look right, I think I'd return it and have the correct one sent to me.

Send a couple of pictures of yours and theirs where the issue is so they can correct their issue.

[Joe L.]

Re: Early vs. late 1969

Bill-----

There are 2 1969 radiator supports that are very similar. These are the one used for small block with copper/brass radiator and the one used for big block with copper brass radiator (all big blocks except L-88/ZL-1 with 4 speed). The only difference between these supports is the location of the right side lower "stirrup" mount. The lower studs for mounting the fan shroud are attached to the "stirrups".

Since the core width of the big block radiator is greater than the small block radiator, the dimension between the "stirrups" is different and, consequently, the dimension between the shroud mounting studs is different. I think that's your problem. You have the big block support and not the small block support. You can confirm this easily. Measure the dimension between the 2 lower studs. If the center-to-center dimension between the studs is 26-1/16", then you have the big block support.

With a big block support, your problem is actually greater than just the shroud mounting problem. The small block radiator will not fit properly withing the "stirrup" width of a big block support.

The only way to modify the support to work would be to remove the right side "stirrup" and re-weld it at a position to fit the small block radiator (about 1-1/2" inboard). This will solve both the radiator mounting problem and the shroud mounting problem. Usually, the big block supports will have the additional mounting holes on the upper right side to mount the bolt-on upper stirrups for both the big block and small block radiators. If not, you could drill the holes you need.

Notwithstanding the above, I would not modify the support, at all. You should expect to receive the correct one from the supplier in the first place-----not one that you have to modify to work.

[Mark #28455]

once you mess with it, NO REFUNDS

Saves the vendor a lot of hassle, they just blame it on you and don't have to replace it - then you're screwed! SORRY, I'm just getting cynical about many of the vendors as quite a few seem to have no sense of fair play.

Mark

[Bill Stephens]

Re: once you mess with it, NO REFUNDS

I'm getting pretty cynical about vendors too after this. The guy on the phone when I called basically told me it was the right one (bacause that's what the catalog says) and if I didn't like it to return it. I've had pretty good luck with these guys before, but I'm finding if you have a problem, don't expect any knowledgable help. The only reason I was tempted to modify it is I'm going to end up paying almost as much in shipping as I did for the part. Anyway, I'm going to ship it back and find it somewhere else. Thanks for all the responses.