early or late cars

[Anthony C.]

What would be the cut off date or build date or vin # be in regards to an early 69 car and late 69?What determines this ?

[Kent K.]

Re: early or late cars

It all depends upon the particular component you're concerned about. Some 'early components' became 'late components' or 'mid-year components' earlier than others. Wheeeeeew
Perhaps if you describe your what you're concerned about, we could help better.
Regards, Kent

[Anthony C.]

Re: early or late cars

My car has a nov 5 68 build date .Judging manual states early 69 smog pump had vents late cars non vented.I have seen an original owner car dec 68 427/435 car with a vent and i have seen earlier cars with no vent.My car is a 427/435 what is the correct pump.

[Dick W.]

Re: early or late cars

Anthony, we generally look for non vented pumps on '69's, with the exception of L/88 cars which were vented.

[Joe L.]

Re: early or late cars

Anthony, we generally look for non vented pumps on '69's, with the exception of L/88 cars which were vented.

I agree. I've never seen a known-original 1969, except L-88/ZL-1, that had a pump with a pressure relief valve ("vent"). While one of the 1969 big block AIM drawings does show a "plug" (which is actually the part that sets the relief pressure of the 68-style pump), I believe the "plug" is an anachronism resulting from a 68 drawing being used. Beyond that, the 1969 big block AIM page shows that the big block uses the "production" pump. The "production" pump means the same pump as used for the base engine which is exactly the pump that I believe all 1969 Corvettes except L-88/ZL-1 originally used.

Also, keep in mind that the pump usually supplied when a rebuilt pump is obtained for a 1969 is the pump with the integral relief valve. Also, the pump that GM supplied in SERVICE for many years (but not original SERVICE) was a pump with the integral relief valve.

The pump with the integral relief valve will work perfectly for any 1969 Corvette, though. However, the 1969 style pump without relief valve should not be used for any 1968 model or any 1969 L-88/ZL-1.

[Marc R.]

Re: early or late cars

Nice avatar Dick. I haven't been up to the hills in awhile--nice reminder of the scenery.