Stumble off idle -

[decooney]

John,
I think QFT could get you very close on the first or second try with a few adjustments. If you have a really good local tuner who knows Holley carbs well, it would be worth a discussion at least. Our local tuner here truly knows Holley; sort of blew me away. You could do a Holley HP or a QF carb, but from what I just went through with QF, their carbs are a level in design, material and build quality above the Holley HP in my opinion. In addition QF will build you a carb from scratch from the custom shop for no extra charge; or they did for my car - you can ask them. I just did this for my best friends Lister project and all new motor. Your motor is close to mine in setup only you have a tad more cubic inches. What we all have to remember here is most of these places base specs on heavier street cars. You are running a 2550lb or so Cobra with fairly open sidepipes and I'm assuming periodic vs. daily use. You could even possibly get by with a custom built Quickfuel 750 (they are a different beast), but I'm thinking Phil will tell you to go with an 850 for a Cobra performance application. He did for my car. They use a combination of different throttle size bodies mixed with specific venturis so you don't lose throttle response and you get more flow. We did have to do some fine tuning on my buddies QFT 750 but they helped us over the phone and email. Its interesting, the metering blocks and what they are doing on the QFT carbs is really nice. Just the billet fully adjustable metering blocks (don't warp) alone are worth it. You could call the Holley Tech line and ask the same questions as QFT to get a good feel for both, before you see your tuner. If you were not so far, I'd send you my own Holley 830 HP to try it. Let us know how it goes and what model QFT or Holley anyone recommends to you for your particular application.