I am looking at a couple of carbs on craigslist, and was wondering what I should use. The first one is a rebuilt Q-Jet for $60. The second one is a 625 Speed Demon, with electric choke, and vacuum secondaries..that needs to be rebuilt...for $125. The Barry Grant rebuild kit is about $60. The car is a 1991 Camaro RS Convertible...with a 305 and a 700R4. This is what I have planned for the car:

Edelbrock filter assembly w/ K&N filter (already have)
Holley Street Avenger 670cfm Carburetor (already have)
Professional Products Carb Intake (already have)
059 Vortec Heads (already have)
Hedman Hedders 1 5/8 Long tubes (already have)
LT1 Cam, Springs, and Retainers (already have)
GM HEI Distributor with Mallory components (already have)
Mallory 4309 AFPR (already have)

Cam

 

you need tosit down and really ask yourself "what am i using this car for most" and then build your carb accordingly. if its a drag car then some carbs/mods might not be so street freindly and on the flip side if its a street car with an occasional strip action you might set it up for the street but not get max benefit from it. also power and "mileage" dont tend to go hand in hand so much with a carb. with that said if its a street car and you set it up right theres absolutely nothin wrong with the qjet. theres arguements back and fourth but when done right a qjet tends to give you a little of all worlds. the one i had had no problem going low 12's and 13-14 mpg ....

 

It will mainly be a street car. Some drag racing on occasions for right now. I may add some nitrous at some point as well; but that will be later on.

Cam

 

Heads have any port work done? how bout the intake? id say a carb under 700cfm will work anything id say somthing like this would work http://www.summitracing.com/parts/HLY-0-80555C/

 

The heads and the intake are completely stock...no porting. I may end up porting the exhaust side of the heads some...but we will see about that. I like that carb, but don't like the $373.75 price tag. I was looking for something around 650cfm. I found that Demon carb, that is a 625cfm, on craigslist. I can get it for a $100, and the rebuild kit would be another $60. The reason I was mainly looking at the Q-Jet is because I can get it for $60, and it has already been rebuilt. It came factory on a lot of GM vehicles...many stock SBC and some BBC. That being said, I'm sure that it would be enough for a warmed up 305...I just didn't want it to be too much, or not worth using at all for my setup.

Cam

 

I would stay away from demon carbs a holley style carb is the way to go very easy to adjust and change jets summit has remanufactured holley carbs on there for alot cheaper

 

So you would recommend the Q-Jet over the Road Demon, of the two carbs I was asking about, right? And you would recommend a Holley over most anything else I take it?

Cam

 

Stick with the q-jet.

Exactly which intake do you have?

 

Right now I have the Performance Products Vortec carb intake. I may end up getting a Edelbrock or GM Vortec carb intake though.

Cam

 

I ended up getting a Holley Street Avenger 670cfm carb from a TGO member. I have updated my first post to reflect the carb and other things that I have recently purchased...mainly for me to keep track of everything that I have and need.

My question now is: how much better would a Edelbrock RPM Air Gap Vortec intake be, compared to the Professional Products Vortec intake that I have?

Cam

 

Which Professional Products Vortec intake do you have?

 

I think that it is the Cyclone one. I haven't seen any kind of model number on the intake itself, but the Cyclone one looks like the only dual pattern intake that they make.

Cam

 

The Crosswind is a true dual plane. But, you should be able to tell the difference between the Cyclone and Crosswind by the gap or lack thereof under the plenum.

Is yours square bore only, or will it mount either a spread bore or square bore carb?

 

There is no gap under the plenum. So I guess that I have the Cyclone.

My intake has the dual pattern, for the spread and square bore.

Cam

 

Okay, that's the idle-5500 RPM Cyclone.

(Whew!)

Now, we can address your question about the Performer RPM.

It would help the upper end power without a significant effect on the lower RPM power.

BUT...

I'm not sure how much difference it would make with 059 heads. Most discussions involve 906 or 062 heads.

 

So probably just stick with the Cyclone intake for now?

Cam

 

yep I would.

 

I think that I will at least try it first. If I end up getting the heads machined, and going with a LT4 cam, I will probably go with a Edelbrock RPM Air Gap intake.

Cam