4294x4

Which would you all prefer to run on a primarily race motor that sees little street use, a Holley 500cfm 4bbl carb (center hung float bowl) on a 4bbl conversion manifold, or the Yaw performance carb on a stock manifold? Consider drivability, throttle response, power curve, and tunability. The car would see RPMs past 7500 often and would be used for Rally racing and Rallycross. It also has a header and free flowing exhaust.

peejay

The stock Nikki is also a 4-barrel...

I'd go with the Nikki.

Rallyon

One of the more successful prorally teams (Gillespyand Kilpatrick from Colorado) are running a Yaw carb on their 1st gen & they love it. They found that Yaws selection of jets was right on.

FB + AWDDSM

I'd take a Weber over both. Then a Yaw though.

Yaw over Holley!

crazy dog

I'd go with the yaw and I hope to one day soon

hanman

I don't know anything about the Holley (exception their reputation for quality is not very good), but I own a Yaw and it rocks. Paul is a good source, and a lot of the guys who race use them, so there is more information out there. With SCCA racing the Yaw is legal too. That makes the decision easy for a lot of guys. Depending on what class you are in of course.
just my opinion,
hanman

riffraff

i thought about going with a yaw rebuild, but i want a side draft carb. so assuming i cannot find a delorto, which i doubt that i can for a 13b street ported engine, i am probably going to get a weber.

peejay

A Yaw carb is not a "rebuild", it's more of a re-engineering. Just something to keep in mind...

riffraff

ahh.. thanks peejay.

4294x4

So, from your experience, are the Yaw carbs bolt on and go or do you have to do some tuning after you put it on your engine.

peejay

Everyone says they need more tuning. But then, even the stock carb is badly out of whack as far as tuning goes.

yayarx7

there is no such thing as a carb that bolts on. All should be tuned for the particular engine. Then again, I never tune mine if they run halfway decent.

Sterling

If yer too scred or too lazy to learn how to tune a carb, then don't bother getting a Yaw. It'll just be a waste of a great carb.
"Bolt - on & go..."? Where do ya think y'are; Legoland?!

Sorry to break it to ya, but going fast with a carb requires a little...ahem...EFFORT!

4294x4

I was simply trying to get a feel for other peoples experiences with the carb. That is all.

Another question: What is the small buterfly valve in one port of the stock intake for? Can it be removed?

peejay

That little butterfly valve is the shutter valve butterfly. It shuts airflow to the rear rotor on deceleration, which helps eliminate exhaust popping, the rotary's tendency to shake when decelerating at low RPM, and increases fuel economy.

If you want to disable it, you can remove the shutter valve (the snorkus thing that attaches to the shaft) and block off its mount on the intake manifold, and wiring the valve open. It's not recommended to remove the shaft, though, since without it the port area for the rear rotor will be a lot bigger than the front rotor. There isn't enough metal to open up the front rotor's runner to match, and even if you could, you wouldn't want to because then it'd be too big.

If it's working, and your setup is stock, might as well leave it alone. It's not really hurting anything.