4-hole carb. spacer on Quadrajet
05-01-2008, 08:59 PM
#1
Burning Brakes
Thread Starter
4-hole carb. spacer on Quadrajet for improved mileage
Has anyone tried using a straight 4-hole carburetor space under their Quadrajet on a LS-5 to improve gas mileage? I know a spacer will possibly shift the torque/horsepower bands up or down a bit, but I am not concerned about that. The stock 70 LS-5 with 390 HP and 500 foot pounds of torque is plenty enough for me. I am interested to know if a short spacer, say 1/2" or 5/8" would improve mileage? If you have tried this, I would like to hear about the results.
Last edited by longbros; 05-01-2008 at 09:54 PM. Reason: error in title
05-02-2008, 07:13 AM
#4
Race Director
have u read my report, http://community.webtv.net/MATTGRU/carb
(search will probably confuse more than help, lots of usless comments to wade thru)
report your results!
(search will probably confuse more than help, lots of usless comments to wade thru)
report your results!
Last edited by Matt Gruber; 05-02-2008 at 07:36 AM.
05-02-2008, 09:33 AM
#5
Burning Brakes
Thread Starter
I did search and read everything I could find. Unfortunately, like a lot of threads, they wander away from the original question or get diluted and side tracked. So, I did not find where anyone had used one on an LS-5 and listed results.
05-02-2008, 09:36 AM
#6
Burning Brakes
Thread Starter
have u read my report, http://community.webtv.net/MATTGRU/carb
(search will probably confuse more than help, lots of usless comments to wade thru)
report your results!
(search will probably confuse more than help, lots of usless comments to wade thru)
report your results!
05-02-2008, 09:53 AM
#7
Race Director
The straight 4 hole spacer for a Holley will not fit on a Q Jet. The Q Jet is a spread bore carb and the primary and secondary holes are different sizes. The Holley 4 hole spacer has all the same hole sizes.
05-02-2008, 09:54 AM
#8
Safety Car
have u read my report, http://community.webtv.net/MATTGRU/carb
(search will probably confuse more than help, lots of usless comments to wade thru)
report your results!
(search will probably confuse more than help, lots of usless comments to wade thru)
report your results!
My intent was to send him to YOUR posts and or thread 'cause it was not that long ago!
05-02-2008, 10:14 AM
#9
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Member Since: Jan 2008
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Fred, I'm looking at an old summit catalog and they sell a 1 inch spacer made for the quadrajet . Improved performance,drivability,throttle response and fuel economy. # SUM-G1424 . 
Hope this info helps , take care,Ray
Hope this info helps , take care,Ray
Last edited by rays71; 05-02-2008 at 10:20 AM. Reason: added name
05-02-2008, 10:20 AM
#10
Burning Brakes
Thread Starter
Thanks so much. I have a couple of Quadrajet spacers I picked up some time ago. I know one of them is 5/8" and the other is something less than that, so I have a couple of spacers to try. I was just trying to get some input about previous experience before I went about swapping in spacers. I guess I will just have to get to it and put one on there and see if it improves the mileage.
