Anyone with a sbc with a blow-thru carb setup? If you drive your car on the street? How streetable is it? What kind of gas mileage do you get? I want to go this route, because its cheaper and easier than efi, but don't want to get less than 10mpg. I know this setup is also very capable of high power numbers(turbo mustangs 1200+ rwhp) I know most of you don't care for economy, but with gas prices near $3 per gallon, and I want to drive my car as much as possible, so give me your opinions.

 

If your going to go that route dont expect good gas mileage. I would highly recomend the carb box. My buddy tried to use the blow through carb with a supercharger and it leaned out before he could let off and poof there went his motor.

 

Well. I'm hoping at least 10mpg is attainable, if you tune the carb to run close to 14:1 at cruise speed, while off boost, I hope thats at least possible, but I wanna hear it from people that have done it.

 

Carb box? Why not a carb hat? Why would it lean out assuming he had correct jetting?

 

How will you know the proper jetting. I guess if you want you could but a blow through carb and hat and get it dyno tunned.

 

As long as the carb is set up and tuned right, and you're not always in boost it won't be that bad. I had my malibu out for about a month with the blow through setup and the gas milage wasn't bad at all. I don't have any figures, but it doesn't seem any worse than when I had an n/a 357 with a 670 street avenger.

 

A wideband O2 sensor is a necessity. If you're going to tune it yourself, you have to do your homework on carb tuning. Even if you have a good handle on carb tuning it still might be worth it to you to have your carb set up by a specialist like CSU carbs. Don't be afraid to go with a small carb too. The guys that seem to have carbs that "just work" with very few changes run smaller carbs. One guy on turbomustangs.com is running low nines-high 8's on a 650DP with downleg boosters. Running a bigger carb sometimes requires annular boosters to pull enough fuel. The booster signal is so strong on the smaller carbs that they seem to just pull the fuel that they need with downleg boosters.

 

As good as CSU is I don't think I'll need it. rotoryota from turbomustangs.com ran low 9s on a 358 sbc and the same turbo i'm using, all through an almost unmodified 650 double pumper. He's using the same carb to run 8's with a bigger turbo. www.boostdoctor.com So I think i'll be using a 650 also, because it's much easier to tune than larger carbs.

 

You beat me to it.

 

That's exactly who I was thinking of! If I had to do it all over again I'd start with a 600 or 650. I was having trouble getting fuel out of my 750, drilled pvcr's, smaller bleeds, more jet, and I was still getting a part throttle lean spot and going lean at the top end too. It was getting me nervous so I just said screw it and sent the carb to CSU.

 

anyone know about doing a blowthrough on a carter afb type carb like the edelbrock performer? i plan to run a gt40 based turbo with a 650cfm version......

 

http://www.turbomustangs.com/forums/...threadid=22107

 

thank you sir, thats almost more info. then i can handle.....

 

I too run a blow thru carb. Gas mileage not bad at all at idle/cruise. However I can watch the gauge drop towards E when I'm in it with the drilled pvcr and larger secondary jets.

Like these guys said- watch/search the turbo mustang site. I have learned alot from them.

Matt

 

with blow through we have to boost reference the fuel pressure right?

 

yes

 

Here is what you need

 

i would but i am cheap as hell, plus i just bought a new edelbrock performer

 

This is less costly than a new engine ...

Playing whit a carb not done for a blown trhu will cost you
a lot more !!!

Your choice

 

it will cost me alot less to mod this one with the marine accelerator pump and solid floats then to buy that. Plus if the carter engineers could do it so can i...... www.vs57.com/carb.htm

If i wanted to spend alot of money on a fuel system i would just buy a fuel injection computer and build a custom system.

 

On that carb....what is the line that runs from bowl to bowl?

 

used for pressure equalization on each bowl.