Stock 1/4 Mile performance of ZL-1 or COPO

[J Rod]

Howdy,

I came to this fourm in search of a little help. There have been numerous threads posted recently regarding Supercar performance as of late on corvetteforum.com, z06vette.com, and suprafoum.com. The big argument has been over two things.

1 - With the change from Gross to Net HP ratings there are some who claim that a ZL-1 on made about 360RWHP and that any other numbers are grossly inflated.

2 - That no COPO Camaro or ZL-1 equipped vehicle in an "as delivered state" will run 10's in the 1/4 mile. Now let me qualify this by stating that everyone understands we are not talking about running on F70 polyglass tires. But lets say on a 9" slick. It is also my understanding that headers for these cars were delivered in the trunk, so I lets say with open headers and on slicks.

The only magazine article anyone could produce was on a car that had been balanced and blueprinted and was modified.

Since this seems to be the center of the supercar universe I figured if anyone had either done this in one of their cars, or had links to proof that we could put alot of the speculation to rest.

Thanks in advance for your responses...

[Stefano]

J Rod,
Is 11.04s close enough (eight inch slicks were used as well as open headers).

This was the 'Drag Times' Yenko article and thus used the lower performance L72,not ZL1.

[JoeC]

Dick Harrell tested a 1969 ZL1 Camaro with 4:10 gear and TH400 trans in Super Stock magazine May 1969. The car had open headers, rear spring clamps, and 6 1/2 inch slicks. The remainder of the car was stock. It ran a best of 11.64 @122.15. Harrell commented that the tires were completely inadequate.

[Chevy454]

Stefano:

I don't have our copy in front of me, so don't kill me if I'm worng, but I was thinking the Yenko L-72 ran an 11.94? Still, pretty quick for such few mods.

Harrell did test a "stock" ZL-1 somewhere...I will have to dig it up.

What a lot of people don't realize though, is that the slicks back then and the slicks today are light years apart. B-I-G difference.

[Charley Lillard]

My ZL1 was Tested when new and ran a 13.16 @110

[COPO PETE]

Sorry Charlie, but that reminds me of a VW commercial.....Drivers Wanted! Actually that is a prettty decent time!
Peter


[Edited by COPO PETE (05-10-2002 at 07:29 PM).]

[JoeC]

I agree with Rob it was 11.94 on the Yenko and it had a bad clutch when they tested it. If I remember correctly it was the gold Yenko Camaro with the wierd emblem on back.

When Charley's ZL1 was tested it had the wrong Holley on it. It came from the factory with a 780 vac sec but should have had an 850 DP. It may have knocked off a few tenths or at least picked up a few mph.

[Stefano]

OK guys when I am wrong I'll take it like a man, but I picked the info up from our own site <A HREF="https://www.yenko.net/oldads/yad11.jpg

" TARGET=_blank>https://www.yenko.net/oldads/yad11.jpg

</A> While slightly opimistic I agree, we all know that if it is in print on this site it must be accurate.

I did dig up a couple of magazine reprints/reruns of the same article and they do say 11.94 @ 114.5 mph.

The #3 ZL1 could have turned in better times but for the fact that, Clill was the test pilot. Look at the pictures, it's him 33 years ago

[COPO PETE]

I did'nt realize Charlies car ws tested with the 780! When we rented the track to test for the Pure Stock Drags, the best we could get out of the 780 was 12.80's. When the 850 was put on we finally got it down to 12.40's that day. Also picked up 3 mph! This is on F70-14 polyglas tires. Since then it's gone better yet. Keep in mind we did certify and went with the heads off so they could check and measure everything and look for porting!
Peter

[JoeC]

Pete the ZL1 run of 13.16 was on 15x7 tires. The 15x7 may give a better 60 ft. but the 14x7 will give numerically high gear ratio. Do you think that will have any effect on the ET?