Dalannex

Are the gas tanks for a 68 and a 69 the same? Is there any differences between coupe and roadsters?

Rowdy Rat

The fuel tanks for all of 1968 and most of 1969 (to serial numbers in the 24,000-25,000 range) were the same. These were sealed tanks that utilized a vented cap to relieve any internal pressure. After about July 1969, the tanks were changed to a vented design although I understand that the vented fuel cap used in the earlier cars continued to be used through the end of the model year.

There is no difference in the tanks between body styles (coupe or convertible), but Rochester carbureted cars used a different tank than the
Holley equipped cars due to the Rochester cars requiring a vent line.

Regards,

Dalannex

Rowdy Rat, I've noticed that you are just a living encyclopedia of Corvette info. How do you know all of these fine details all the time anyway? Did you work for GM once? I'm just curious.

I have another question too. 68's only had Rochester or Holley carbs, correct? Mine has a Carter on it. I am just curious. I think I am going to put a performer on it along with an Edelbrock carb when I get that far.

Rowdy Rat

Thanks very much for the kind words... I really appreciate it!

Actually, I was not fortunate enough to work for GM, but mechanical things in general and cars in particular always interested me. I'm just an enthusiast like yourself... I'm involved in the hobby because I get to see some neat cars and meet a lot of great people! :)

You are correct that both Holley and Rochester produced carburetors for Corvette applications in 1968. In addition, Carter built Quadrajets under license as well; the carbs are identified as such ("Carter" is cast into the body of the carburetor) and use a different dating system than their Rochester brothers. In most other respects, the Carter and Rochester Quadrajets are identical.

Regards,

454Big

Stan,

you really are a kind of encyclopedia!
I always thought the gas tanks differ because of the returns - but thinking this over, the return can be done by the cap that houses the sender unit.
Paragon, I guess, sells different tanks for 68 / 69 MY.

BTW: Does your L-89 still have the original heads or have they been replaced some time ago? I think I will need to replace mine in the future....... :cry :cry :cry

Dalannex

I guess I thought until I got the 68 that q-jets were Rochester and that's just the way it is. I didn't know if this Carter that I have was just a q-jet copy or if it was the real deal. Now I know. Thanks.

Rowdy Rat

These are some photos of a late 1969 fuel tank for a Holley equipped car (this particular tank is for a 1970 LT-1 without NA9 which is identical). The first photo shows the vent that was added (it's located at the top right corner of the build sheet) to the later tanks to allow pressure to equalize.



This vent was absent in the 1968-early 1969 style tanks; pressure was equalized with a vented fuel cap that I mentioned in a previous post.

The only other difference in physical appearance that I'm aware of is that the ends of the late tanks have large rectangular depressions. The early tanks have smaller semi-circular depressions.



The fuel tanks for Quadrajet equipped cars in 1968-1969 are identical except that they will have an elbow welded in the right (passenger) side depression for the fuel vent/return line attachment.

Unfortunately, I don't have a photo of a Quadrajet produced by Carter, but the wording on the carburetor body is "MFD BY CARTER CARBURETOR FOR GMC" and is located right next to the "QUADRAJET" script so they're easy enough to spot.

Regards,

Dalannex

Thanks for the info. I appreciate it. I am going to be looking for a tank for my 68 soon, and don't know for sure if I want to try to find a used one or go for new. I am saving this info for future reference though. :yesnod: I have lots of that kind of stuff saved. :D

Rowdy Rat

When you're ready to purchase a new fuel tank you might want to give Quanta a call at (800) 235-8788. They manufacture excellent reproductions of the original tanks along with some of the associated hardware as well. Great company to deal with.

Frank,

Yes, to the best of my knowledge the heads on my car are original. I've been fortunate to trace the entire ownership history of this car and have spoken to all of the owners... None of them ever claimed to have removed the heads from the engine. Add to that the casting numbers and dates as well as physical appearance of the heads is in line with what I would expect; I'm relatively confident these are the ones that it was delivered with.

Your 1968 as well as my 1969 used the 3919842 casting number head, although there is a subtle external difference in the heads that were originally used on your car and the ones used on my relatively late build 1969.

Regards,