str8lnr

all right i started one thread but it ended in vac sec vs mech sec what i need to know is what is the best carb for a street/strip 5.0 my setup is t-5,3.73,hooker sc equal shortys,funnel web intake (switching to a rpm airgap or pp crosswind),f-303, and im going with gt40ps as soon as my budget allows. this car is mostly for strip duty but would really like to drive it on the street every now and again im leaning towards a 4150 600 but im open to suggestins

Portmaster

I commented on this once before and I'll stand by it. In many cases a Vac secondary carb will deliver better performance. set up right it will get you out quicker and keep you lean and mean (not too lean). To really take advantage of a double pumper you need tall gearing, high launch rpm and a light car when only running 302 cubes.

Now I have a big 750 Holley HP series carb now flowing 830cfm on my car I also have a 3500 stall and 410 gears in a car that will weigh around 2700 pounds without the driver (maybe lighter). If my car had a 306 I'd be runing a 650cfm (or somewhere close) DP. By the way the Crosswind flows real nice and I was shocked how well it did in a dyno test so if you can save a few bucks there you'll be OK. The Summit brand Stage three works real well as well. I like budget stuff that works well.

If you are really wanting the double pumper then thats what you should buy. I've run stock classes where I had to run a quadrajet carb (factory GM 4 bbl vac secondary) on a 454 (461 actual) that laid down 575 hp and 550 lbsft of torque. shifting it at 5500 rpm in a 3900 pound car it still reeled off low 11's with all stock suspention. It's a big heavy car that has about 8.5 pounds to pull per cubic inch.

In real life your Mustang weights with fuel and driver about 3400 pounds. Now don't hold me to that number but I have seen a few of them on the scales and every car varies. When you figure it up your mustang has to pull over 11 pounds per cubic inch. If you have lightened your car up below 3000 pounds with driver you may be OK with a Double pumper. Just remember when you move into a double pumper say goodbye to an electric choke. You say mostly strip so you should be Ok with a manual choke.

Here are my Holley recomendations in order and why

Holley 0-80670 Street Avenger 670CFM. It has an electric choke, it's easy for the novice tuner and the adjustments are extremely easy. Great of idle perfomance and throttle responce under heavy load.

Holley 82651 Street HP double pumper. easy to tune for a DP and works well on the street at the cost of a choke. Will stay with you as performance grows and will feed 450 hp. If you have to have a DP this would be the one.

Edelbrock carb

Edelbrock Thunder AVS 1806 650cfm. These are great carbs and are extremely easy to tune. Like a Ronco oven "Set it and Forget it" This carb would be my number 1 pick for your vehicle.

87Stallion

I have the 670 Street Avenger Carb on my car and I feel its too much for my particular setup. However there isn't alot of difference between mine and yours. Now saying that Im at about 3500 ft above sea level so I need to jet mine down about 2 sizes.

I personally would go with a Holley 600 CFM it I had it to do over again.

Just my 2 cents worth

FLcracker9

I've never owned an Edelbrock, so I can't comment on them. I myself run Demons on all of my vehicles (3), and prefer them over the Holleys. I find them easier to tune than the Holleys, and they seem to perform as good or better than the Holleys (although they cost slightly more). A 650 Speed Demon with mechanical secondaries would work fine with a T-5 and 3.73 gears for a mostly strip car. Just my own experience and opinion.

HACKGT350

all i ever hear about demons are they are crap unless you get one from back in the day. they are just poor quality. there was someone on here that bought one and was so disgusted with it he ended up putting all the holley internals with it.

since you want this as a mostly track car i would not go with edlebrock. you cant fine tune them like a holley, quick fuel, or demon, they just look pretty for going to the shows with. at the most i would go with a holley or quick fuel 650 dp starting with smaller jets till you find the sweet spot so you dont over load your engine with gas. your gunna have better flowing heads (gt40s) and a very good intake so you should be perfectly fine with it.

Portmaster

I was selling Demon Carbs out of my shop and really liked the quality look of the carb and the way they were built. Was having so many problems with them not staying adjusted I went back to selling Holley and Edelbrock. I really like the look of the Demon carbs but they just didn't work out. I may have just got a batch of bad ones. As crude as Holleys look they seem to make to most power. If Holley hadn;t sued Barry Grant we could still get those great BG modified Holleys. I put one of the Proform 750 DP on a friends car. If I didn't already have my carb worked over I would have bought one.

Portmaster

Edelbrock bought the rights and molds for the AFB from Carter to start building the performer series carbs. Lots of Big Block Chryslers came with the Carter AFBs on them. Edelbrock does a better job than Carter did and it was a great carb then. A pair of them came on the 426 Hemis and the AVS Carter version was installed on 440/375 hp cars. It's really an under rated carb. The AVS series is really a hot carb.

str8lnr

thanks for the input you sound like you know your crap so ill tell you what ill def go with one of youre suggestins but tell me which you would run and if it dont work out ill not hold that against you because i know every setup is different

HACKGT350

maybe with their bigger carbs but i have never been a fan of them and i know from first hand experience that the holley or quick fuel will give you more power than the edlebrocks but yes they still get the job done just not as well as i want

Portmaster

If you are not very experianced with Carbs the Edelbrock 650 Thunder AVS.
The 670 Holley Street Avenger is also easy to tune and comes with a DVD to instruct you. Either Carb will do you a great job. You will have to buy a duel line for the Holley and if you are cramped for room you will have to buy a special line for the edelbrock so a low profile air cleaner will fit. The total money will be the about the same, performance will be about the same. Both are proven designs. If I was doing it for myself I'd have to flip a coin between the two carbs.

While a Holley that was Modifeid by Quick Fuel Technologies may make more power it's not the carb for the novice tuner.