crashbahl

Guys, What would you recommend for a carb on a LS7 powered Factory Five Cobra? Motor will be stock with 1 7/8 long tube headers and GMPP manifold and MSD 6012 ignition with the high output truck coils.

It's going to weigh under 2500 and have a F-body T56 and 3.27 or 3.55 gears in the rear end.

I talked to Pro Systems after seeing many threads in the Cobra forum that their carbs were great right out of the box but I'm seeing newer threads that have me questioning that.

One thing that Pro Systems said that made a lot of sense was that with my intended combination of street, autocross and drag racing that going with a Holly 830 with it's smaller venturi would provide a better signal and throttle response. This is likely at the expense of top end horsepower but driveability and throttle response is more important.

ZONES89RS

iTrader: (25)

Anything you can find that is 950 cfm rated should work fine for you. Pics of said project or I ban. Lol

speedtigger

iTrader: (16)

^^^ This. Just make sure you plan to buy yourself a wide band. You will need to do some advanced tuning to keep your plugs clean while cruising and idling.

I love those Factory Five kits. I could see myself doing one someday. And, lets see those pix!

crashbahl

950?? That isn't too big? I hear ya on the wideband O2!

So far, all I've been doing is accumulating parts. I have the longblock with all of the accessory drive, intake and ignition stuff, clutch bell housing and the T56 (rebuilt with 32 spline main shaft thanks to LS1Tech! and 89RS!).

Next major purchase is the carb. I'll hopefully order the kit the end of next summer so I can work on it over the winter.

crashbahl

I gave misplaced props. The T56 mod was courtesy of 85MikeTPI!!

Pop N Wood

iTrader: (1)

Too bad Holley doesn't make their dual quad LS intake for the LS7. Seems like a great choice for a motor like that.

dogsballs

dual quads on motor only?!?

nice single plane 850-950 holley would be fine.

ZONES89RS

iTrader: (25)

950 carb on a 427 ci engine that spins 7000 stock? Lol, nope.

fast89stang

iTrader: (2)

950 here. 6.0 loves it.

Pop N Wood

iTrader: (1)

Dual quads on a Cobra replica. Would look great and from what they say about that intake would work great.

But no LS7 version.

crashbahl

950 carbs I've been researching 950 carbs and they are glorified 850s except the new Holley ultra hp 950. Based on that wouldn't I just be better off with a 850?

speedtigger

iTrader: (16)

Actually, they are glorified 750s if you wish. The 850 mechanical secondary actually has a larger venturi than the traditional 950 Holley HP. More specifically, the traditional 950 HP has the same venturi size as the 750 mechanical secondary but the same base plate bore diameter as the 850. I have read some tests that say the 950 HP actually flows arount 840 CFM.

Quick fuel has some carburetors that have larger Venturi sizes. Holley also sells a 1000 CFM 4150 style carb..

If it were mine, I would contact Quick Fuel and find exactly what you are looking for. The Quick Fuel carbs have the adjustability you will need to not only make maximum power, but also achieve clean and efficient cruise air fuel ratios.