Ryan77

I was thinking of running a 1" spacer with an additional vacuum port on my new 383, I did the math and I can definately fit it under the stock hood. My question is, do carb spacers move the powerband up in the rpm range, and if so, how much would a 1" spacer move it up :confused:

comp

yep, open plenium more then a 4 hole, it depends on your combo. it could
help everywhere, :thumbs:

78 Vette

I added a 4 hole spacer (holly) It seems to have gave me more mid range tork. I don't think I lost anything on bottom end I should do another G Tech run with out it. Currently ran a 12.52 at 112 mph. :auto:

AlwaysWave

It's said that a 4 holer helps low end torque and an open spacer tends toward the top end.

I have a 4 holer 1" on mine and it does seem to add some low down torque and it for sure decreased top end performance.

78 Vette

Oops I ment to say I dont think I lost any thing on top end. :crazy:

Pete79L82

There is no definative choice for carb spacers. Every cylinder head/maifold/carb/cam combination will like something different. My dyno experience has shown me that if a motor likes a spacer it will show an increase throughout the entire RPM range. If it doesn't like a spacer than it gererally hurts power throughout the entire RPM range. I have never found any spacer that works on every engine. Most engines (but not all) will benifit with a spacer and generally the taller the better.

Wrecked82

Would a spacer help a crossfire?

Tominator

I think the space that would give you the most HP gain would be a nitrous spacer. :cheers:

BSeery

An open spacer over an open intake will give a bit more top end and upper mid range.

A 4 hole spacer over a dual plane intake will give stonger bottem end and mid range torque.

Ryan77

The motor is 383 built by AR Racing with 525hp@6200rpm and Weiand Team G intake, so I think the open spacer would have more of a benefit :cheers:

l2vette

Where is the best place to buy a carb spacer??

norvalwilhelm

I definitely agree with Pete. A carb spacer is used to tune the carb. A small carb on the low rise intake has a problem with too much velocity through the ventura so the mixture hits the bottom of the intake where you get fuel/air seperation. In this case a carb spacer would raise the carb increasing the space before the mixture hits the intake floor, so a spacer would help in this situation.
Take the same intake, install a larger carb and the velocity slows down through the carb, the mixture doesn't hit the intake floor, no seperation and the spacer does no good.
Unless you have a dyno how can you tell if the carb wants a spacer or not??? I have seen spacer actually decrease horsepower on the dyno.
Your butt is not a very good dyno.

Ryan77

I'm not too worried about it, the car will be dyno tuned and I'll try both with and without the spacer. The intake is the Weiand Team G (part #7530) and I'm running a Speed Demon 750 with mechanical secondaries and no choke :cheers: