[bammazon]

Just a quick question on carb spacers. How do you determine if one is needed or not?

I have trick flow 23* heads w/ 62cc 195cc intake runner. I am using the edelbrock Performer RPM air-gap intake, and the Holley 670 street avenger. The cam is a crane cam. P/N 967601 grind # 3863151

I am currently using a carb spacer, but my Uncle recommended I take it off, so I would like to know what determines the need. as far as I know, it just helps keep the carb cooler so It should help rather than hurt anything right?

[cobalt327]

A couple thoughts on spacers, not all-inclusive by any means-

Often as not, a spacer is a trial and error type thing. The best thing I can suggest is to do runs both with and w/o to determine whether your combo 'likes' one or not.

There are rules of thumb that I've heard through the years- "only use open spacers on open intakes"; "4-hole spacers only help the bottom end", "open plenum spacers need to be 2" to matter", "if you use an open spacer on a dual plane, it'll kill the bottom end", etc, ad nauseum. For every one of these "truisms", there's instances of the opposite results being obtained.

Sometimes the positive results are nothing more than the insulation properties of some spacer material that isolates the carb from heat.

A spacer WILL allow the fuel/air mixture to make the turn easier into the runners, this extra distance and increase in plenum volume can result in less signal felt at the boosters, which in turn can require more jet to compensate. Or not- that's the reason that you have to try them and compare the results.

Best bet IMO is to try them all and chart the results unless you have access to a dyno.

[malc]

You might find this CJTV video interesting.
I tried a one inch four hole spacer on my Edelbrock Air Gap and it was a disaster, then I tried a Summit aluminum one inch open, fanatastic.
Now I´m using a Summit aluminum two inch open spacer, fantasticer.

[my87Z]

i dont think i would use a spacer with the air-gap intake but i would use it with the rpm intake, the air-gap already has a higher plenum like the victor but is still a dual plenum intake. i personaly am not a fan of the air-gap intakes i would rather use a performer rpm with the plenum divider notched and a 1" open spacer. if you look up bang suck blow on you tube you will see where they did comparisons of the victor intake, air-gap and rpm, then another comparison of the air-gap and a rpm with a notched plenum divider and 1" spacer.

[malc]

Originally Posted by my87Z

i dont think i would use a spacer with the air-gap intake but i would use it with the rpm intake, the air-gap already has a higher plenum like the victor but is still a dual plenum intake. i personaly am not a fan of the air-gap intakes i would rather use a performer rpm with the plenum divider notched and a 1" open spacer. if you look up bang suck blow on you tube you will see where they did comparisons of the victor intake, air-gap and rpm, then another comparison of the air-gap and a rpm with a notched plenum divider and 1" spacer.

See my link in the post above.

[my87Z]

Originally Posted by malc

See my link in the post above.

shoot the CJTV through me off but that is the one

[bammazon]

great video, I was actually debating between the air gap, and the Victor. Glad I decided to go with the air gap. Thanks for the input guys, I may try runnin it without the spacer and see what happens.

[Chevrolet4x4s]

Do they still make the stepped type four hole spacers? Supposed to have a venturi effect,I bought some 80s magazines the other day and was reading about them.
Shane

[cobalt327]

Originally Posted by Chevrolet4x4s

Do they still make the stepped type four hole spacers? Supposed to have a venturi effect,I bought some 80s magazines the other day and was reading about them.
Shane

They're still around , THESE bust hell outta a buck fifty, some of them.

For a spacer.

'Course, it "Adds up to 47 HP naturally aspirated, and 500 HP with nitrous oxide."

[Chevrolet4x4s]

Is the 500 with a 490 shot haha?
Shane

[V8 Super Beetle]

After looking at that video I have a question. Would the results of the RPM intake with the machined divider and a 2" open spacer yield similar results compared to an Air Gap with a open 1" spacer?

I have an RPM intake on my setup with a 2" open spacer and it didn't affect the bottom end any, that I can tell, cause I still can light them up around 2,000 rpm. Throttle response is still great, doesn't bog and I can't really tell the difference in top end performance yet cause either way I'm reaching for the "Oh *****" handle when I gas it.

[malc]

I went for the one inch spacer initially because I have the Airgap designed for the Q Jet which does not have the divider milled down.
The milled divider lets the motor get fuel from all four barrels of the carb,
when I had the four hole spacer each side was feeding off only two barrels,
did´nt idle well or accelerate smoothly.
Comparing my original one inch four hole spacer setup to my two inch open, it´s a world of difference car pulls much harder right off go.

[Nemeth]

Hello every one I had a 4 hole spacer atop my performer rpm air gap it really did not pull well.I have a sbc 383 rhs heads 180 cc runners 10.5 to 1 comp 236-242 @ ,050 .550 lift 110 lsa.670 worked avenger.
I installed a 1 inch open spacer....engine came to life and pulls hard mid range.
Seems an engine with after market heads and a decent size cam with a dual plane manifold do much better with open spacers.

How ever an engine with mild build like my 327 with vortec heads performer intake,600 eddy carb comp 218-224 @ .050 9 to1 comp run better with a 1 inch 4 hole spacer.Smaller builds need more velocity for the low end torque.

That is my conclusion after testing both engines with different spacers....

SO YES SPACERS USUALLY DO MAKE A BIG IMPACT ON ENGINE PERFORMANCE !!!!!!!!!!!!!

[vinniekq2]

old thread, can you post your dyno runs on a new thread?

[techinspector1]

Originally Posted by Chevrolet4x4s

Is the 500 with a 490 shot haha?
Shane

LMAO...........