Holley carb spacers - Why?

GJUK · Post by **GJUK** » Mon Dec 23, 13 1:30 pm

Hi,
Another question from the newbie.
Do carb spacers increase the torque or similar on an engine?

Cheers

Jon

Adrian Worman · Post by **Adrian Worman** » Mon Dec 23, 13 2:20 pm

A good question and a really interesting subject, but in a nutshell yes, increasing plenum volume will usually help torque at the lower end and help with 60 foot times.
Tuned cars benefit more than stock but loads of things can alter or affect the the actual difference it will make.
The drag racers on here will fill you in on that

Blue · Post by **Blue** » Mon Dec 23, 13 3:31 pm

The other benefit of a spacer is to isolate the carb from engine heat, which is why some are made of plastic or phenolic (wood).

GJUK · Post by **GJUK** » Mon Dec 23, 13 4:17 pm

Any problems with having a spacer, does overall bhp drop?

Adrian Worman · Post by **Adrian Worman** » Mon Dec 23, 13 4:26 pm

It would be very unlikely, on any engine it will give some benefit in keeping the carb cooler, as Blue states, but i doubt it would hurt performance.

Mick · Post by **Mick** » Mon Dec 23, 13 6:26 pm

I fitted a 2" supersucker and picked up .15 and nearly 2 mph, back to back runs.
Mick

Les Szabo · Post by **Les Szabo** » Mon Dec 23, 13 7:18 pm

two and a halve inches of spacer.....inc N20 plate.

db · Post by db » Mon Dec 23, 13 7:35 pm

On Les's advice I got one just like that!

If you go that tall you need to check hood clearance and you may need to tweak your throttle bracket, etc.

You also need longer studs, Bozwell on here made me some nice ones

Raising the carb does make it easier to work on!

Jon Connolly · Post by **Jon Connolly** » Mon Dec 23, 13 8:01 pm

Yep

Different types and sizes of spacer have different effects .. I think the idea is you create low pressure air downstream of the carb which in turn lets more air go through the carb ??

I used an open one but have now changed to a supersucker, also used a wedge plate to keep carb level under acceleration

andyrob · Post by **andyrob** » Mon Dec 23, 13 8:23 pm

a small wooden carb spacer made me pick up 2 mph !!! cost £15

best £15 ive ever spent

Mossy68 · Post by **Mossy68** » Mon Dec 23, 13 8:57 pm

What are the wooden type made of ?
I would assume a marine grade ply or similar ?

If so perhaps I could make up a jig and route them out of ply scraps
I could do various thicknesses so could be glued together for different heights ?

db · Post by db » Tue Dec 24, 13 8:14 am

This stuff...

http://www.ebay.co.uk/itm/PHENOLIC-SHEE ... 53ef34466c

I bought a 2" spacer, then made a 1/2" adaptor to blend my carb profile into my inlet profile.

Mossy68 · Post by **Mossy68** » Tue Dec 24, 13 10:43 am

Cheers Paul.
Remember your thread now.

GJUK · Post by **GJUK** » Fri Dec 27, 13 1:05 pm

May I ask please if these spacers are 'universal'.

Does one fit all?

Thank you

Jon

Blue · Post by **Blue** » Fri Dec 27, 13 1:37 pm

Almost, all 4 barrel Holleys use the same bolt pattern except for the Dominator which is much larger, you don't want one of those.