Carb spacers

[65notch]

i need opinions on car spacers...
they are pretty inexpensive and easy to install so im curious to hear everybodys opinions on them.
i have a 289 .030 over performer rpm intake and performer carb. stock heads. what do you guys suggest as for me getting one, and if so what kind. i see there are different sizes, materials, styles ect.
thanks

 

[GrandeStang73]

Doesny have to be thick, its just a peice of high specific heat plastic to try and cool the air to dense up the air flow. Might see a lil more throttle response but not much in HP or Torque. I recommend Mr.Gasket or anything made out of G-10 Plastic.

 

[65ShelbyClone]

About all the non-metal spacers do is insulate the carb from heat like Grande said. Phenolic is good, but I wouldnt go over 1" thick. Its said that installing a spacer will move the power band up some, but I think you'll see it on a dyno chart alot more than you'll feel it.

 

[68 Coop]

I agree here, you won't really notice any difference. I added one (plastic) from the Zone, fits well, but no diff in the end.

 

[FORCED2DV8]

Yeah you will see a small increase on the dyno but you wont feel any diffrence.

 

[krash kendall]

I had to use a 1" dual plane aluminum spacer to get my edelbrock 600 up high enough to clear the Elite series tall valve covers. The added manifold volume is supposed to provide snappier throttle response, but I can't verify anything as I can't run the car without it.

The one negative thing is that you will double the gasket mating surfaces (four instead of two), which increases the chances of a vacuum leak. I had to crank my carb down way over spec in order to stop the vacuum leaks so I could pass emissions testing.

 

[thehueypilot]

I put a 1" phenolic spacer on my Vic Jr and I can say it may no differnce to the 1/4 ET or MPH. If it lowers the heat transfer into the carb (it should) I could not really tell a difference in ET or MPH, but then again I did not measure the actual temp of the carb before and after. It felt very hot to the touch either way.

 

[SoCalCruising]

What have read is that the benefits are highly variable and dependent on your overall combo. Some say not to bother with a spacer on a Vic Jr. unless it is 2" (open), which becomes a hood clearance problem for many of us. As for dual plane, results range from worse performance to marginally better. A 1" open spacer will increase plenum volume, but defeats some of the dual plane ("180*") design by allowing plenum sharing from one side to the other. A 4-holer would preserve the dual plane design. Again, results are varied. All spacers increase plenum volume and provide more vertical space for the air/fuel mixture to make the 90* turn from the carb to the runners, which sometimes helps (less puddling of fuel at the bottom of the plenum. If material is also a thermal barrier, then some benefit from isolating the carb from manifold heat may be had.

 

[brianj5600]

I put a 1/2" spacer on mine and gained nearly 200hp! But really you have to try it to tell, and there are alot of designs. From what I've read the tapered ones rule.

 

[Edbert]

Longer runners are supposed to help the bottom end not the top end, to improve top end you want shorter runners. So one would not expect to see lower ETs or higher peak dyno numbers by adding a spacer.

But the driveability should be improved slightly for normal street (as in commuting or cruising) RPM ranges.

 

[mustangprodude]

My '83 vert came with a 1" aluminum spacer. I took it off when I tried a friends carb and never put it back on when I reinstalled my carb. No difference. It's now looking cool hanging on my shop wall.

 

[TOM B]

I remember HOT ROD did a story on this but I cant find it. They dino'd before and after a spacer was installed. What they found was a little torque increase in a 1/2 to 1'' spacer but then when they went thicker it fell back off. Makes sense though, That why you buy a high rise manifold or tunnel ram to increase your power band.