Carbs - Page 3

Jim Cimarolli · 06-22-2007, 10:02 PM

Thanks Dwight,
I know that the present '69 Chevy 427 combo that is being run at 445 hp has an 830 cfm vacume operated secondary carb on it. I did not know of ANY combination in the stock eliminator classification guide pre-1970 that came from the factory with an 850 Holley Double Pumper Carburetor.

Jim Cimarolli

Alan Roehrich · 06-22-2007, 10:38 PM

For the 69 ZL-1, NHRA lists the Holley R-4296A. Holley lists the R-4296 as an 850 double pumper. Shows a 0.025 primary squirter and a 0.035 secondary squirter, and a 4150 series, with metering blocks front and rear. Shows it to have 1.750 throttle blades and 1.562 venturis. Same carb is listed for the 69 L-88.

The ZL-1 is rated at 445HP by NHRA, and the L-88 at 440HP.

I will say I've seen several carbs for sale listed as L-88 and ZL-1 carbs that ARE vacuum secondary.

Supposedly at least some of the ZL-1 cars were delivered with the R-4346A carb that came of the L-72 427-425HP cars, and the carbs had to be swapped before they could race.

Alan Roehrich

Bring "AA" classes to NHRA Stock Eliminator!

Jim Cimarolli · 06-22-2007, 11:50 PM

Thanks Alan,
Will NHRA allow a double pumper carb on the ZL-1?

Jim Cimarolli

Kevin Helms · 06-23-2007, 12:12 AM

Jim,

Are you still on here?

Sherrie

Kevin Helms · 06-23-2007, 12:16 AM

Can anyone tell me where I can find some info on the race that's going on right now in Tulsa?

Sherrie

John Kelley · 06-23-2007, 01:03 AM

The FastNews guy probably won't be there until tomorrow.....

Kevin Helms · 06-23-2007, 01:10 AM

Thanks but I finally found out the results. I just thought they were posted somewhere and I thought Jim might know but I guess the 'ol man went to bed?!

Sherrie

Oldtimer · 06-23-2007, 09:23 AM

JIM, Alan is correct, 69 L88 vette and the ZL-1 Camaros can run an 850 DP

bp4133 Bob Pagano

Alan Roehrich · 06-23-2007, 10:05 AM

Having not carried ours to the track yet (it ain't even on the dyno yet) I can't tell you what tech is accepting at the track, only what the rulebook and the blueprint sheet call out, and what the Holley tech guide says. The only person I know successfully running a fast L-88 in NHRA is Steve Calabro, maybe Steve will drop by and say what is on his car.

Again, I have SEEN vacuum secondary 850 carbs CLAIMED as correct for the 1969 427-430HP engines, and been told they are legal. The new looser rules on carbs MAY mean you can run either or, provided it is the correct size and model. Maybe Travis will check in again and give us another clarification.

Alan Roehrich

Bring "AA" classes to NHRA Stock Eliminator!

Dwight Southerland · 06-23-2007, 10:21 AM

The '69 L88 and ZL1 carb was an 850 DP. The R-4296 that is listed in the blueprint specs is described by Holley service manuals as a DP and if you have ever seen a restoration you know that it is. The '67 and '68 L88 engines (R-3418 and R-4555 Holleys) were 850 vacuum secondary carbs.

06-22-2007, 10:38 PM	#22
Alan Roehrich Veteran Member Join Date: May 2006 Location: Murfreesboro TN Posts: 5,118 Likes: 1,573 Liked 1,837 Times in 417 Posts	For the 69 ZL-1, NHRA lists the Holley R-4296A. Holley lists the R-4296 as an 850 double pumper. Shows a 0.025 primary squirter and a 0.035 secondary squirter, and a 4150 series, with metering blocks front and rear. Shows it to have 1.750 throttle blades and 1.562 venturis. Same carb is listed for the 69 L-88. The ZL-1 is rated at 445HP by NHRA, and the L-88 at 440HP. I will say I've seen several carbs for sale listed as L-88 and ZL-1 carbs that ARE vacuum secondary. Supposedly at least some of the ZL-1 cars were delivered with the R-4346A carb that came of the L-72 427-425HP cars, and the carbs had to be swapped before they could race. Alan Roehrich Bring "AA" classes to NHRA Stock Eliminator! __________________ Alan Roehrich 212A G/S

06-23-2007, 09:23 AM	#28
Oldtimer Junior Member Join Date: Jul 2002 Location: Arkansas Posts: 87 Likes: 0 Liked 0 Times in 0 Posts	JIM, Alan is correct, 69 L88 vette and the ZL-1 Camaros can run an 850 DP bp4133 Bob Pagano __________________ Bob Pagano L88BOB@aol.com www.dyainc.org 4033 AA/SA

06-23-2007, 10:05 AM	#29
Alan Roehrich Veteran Member Join Date: May 2006 Location: Murfreesboro TN Posts: 5,118 Likes: 1,573 Liked 1,837 Times in 417 Posts	Having not carried ours to the track yet (it ain't even on the dyno yet) I can't tell you what tech is accepting at the track, only what the rulebook and the blueprint sheet call out, and what the Holley tech guide says. The only person I know successfully running a fast L-88 in NHRA is Steve Calabro, maybe Steve will drop by and say what is on his car. Again, I have SEEN vacuum secondary 850 carbs CLAIMED as correct for the 1969 427-430HP engines, and been told they are legal. The new looser rules on carbs MAY mean you can run either or, provided it is the correct size and model. Maybe Travis will check in again and give us another clarification. Alan Roehrich Bring "AA" classes to NHRA Stock Eliminator! __________________ Alan Roehrich 212A G/S

06-23-2007, 10:21 AM	#30
Dwight Southerland VIP Member Join Date: Dec 2001 Location: Arkansas - In the middle of everything. Posts: 2,001 Likes: 64 Liked 780 Times in 194 Posts	The '69 L88 and ZL1 carb was an 850 DP. The R-4296 that is listed in the blueprint specs is described by Holley service manuals as a DP and if you have ever seen a restoration you know that it is. The '67 and '68 L88 engines (R-3418 and R-4555 Holleys) were 850 vacuum secondary carbs. __________________

06-22-2007, 10:02 PM	#21
Jim Cimarolli Senior Member Join Date: Mar 2002 Location: Sulphur Springs Texas Posts: 743 Likes: 146 Liked 166 Times in 46 Posts	Thanks Dwight, I know that the present '69 Chevy 427 combo that is being run at 445 hp has an 830 cfm vacume operated secondary carb on it. I did not know of ANY combination in the stock eliminator classification guide pre-1970 that came from the factory with an 850 Holley Double Pumper Carburetor. Jim Cimarolli

06-22-2007, 11:50 PM	#23
Jim Cimarolli Senior Member Join Date: Mar 2002 Location: Sulphur Springs Texas Posts: 743 Likes: 146 Liked 166 Times in 46 Posts	Thanks Alan, Will NHRA allow a double pumper carb on the ZL-1? Jim Cimarolli

06-23-2007, 12:12 AM	#24
Kevin Helms Junior Member Join Date: Dec 2001 Posts: 33 Likes: 0 Liked 0 Times in 0 Posts	Jim, Are you still on here? Sherrie

06-23-2007, 12:16 AM	#25
Kevin Helms Junior Member Join Date: Dec 2001 Posts: 33 Likes: 0 Liked 0 Times in 0 Posts	Can anyone tell me where I can find some info on the race that's going on right now in Tulsa? Sherrie

06-23-2007, 01:03 AM	#26
John Kelley Senior Member Join Date: Feb 2002 Location: Tightwad,TEXAS Posts: 911 Likes: 6 Liked 3 Times in 3 Posts	The FastNews guy probably won't be there until tomorrow.....

06-23-2007, 01:10 AM	#27
Kevin Helms Junior Member Join Date: Dec 2001 Posts: 33 Likes: 0 Liked 0 Times in 0 Posts	Thanks but I finally found out the results. I just thought they were posted somewhere and I thought Jim might know but I guess the 'ol man went to bed?! Sherrie