I'm replacing a single 1250 4500 Dom. carb on a single plane Ray Barton that made 950 HP with a Ray Barton cast alum crossram. It has 13:1, .805 roller cam I've been told I need vaccum secondaries for the 4150 style carbs any advice on brand & size?

Thanks Brian

PS The motor is going down in a 68 dart with a tranny break

You have the best or one of the best in your home state. Love his stuff; Dale Cubic of CFM.

http://cfmperfcarbs.com/

The original crossram carbs were vacuum secondary but I don't guess you have to run them that way. I think you can still buy the original new 4235/4236 Holleys for about $750 each.

Just depends what you're trying to accomplish. I don't see any reason to put original carbs on there unless the rules require it. Do you have a budget limit? Are you trying to make as much power as possible? Without any idea of what you're doing with the engine it is hard to make a recommendation.

A pair of HP 950's would really wake that big motor up!

Andy
No they don't have to be orginials and of course I'm wanting to make as much HP as possible, what do you suggest? This is a 100% race car

Thanks Brian

My recommendation would be a pair of the new all aluminum Holley carbs. You'll save a bunch weight and they are fully adjustable. Most people don't even understand all the new adjustment capabilities on the new Holley carbs since they haven't been out very long. The new carbs are so much better than anything in the past that there just isn't much reason to use anything else anymore unless the rules require it.

Size is a little tougher choice, a pair of 750 carbs would probably be my choice.

If you're comfortable with carb tuning and have a wide band setup on the car then I'd recommend just buying a pair of new aluminum 750's from Summit and bolting them on. If you don't want to mess with tuning then give a carb tuner a call and have them tweak a pair of carbs for you. BLP is who I work with but there are other tuners out there.

If you are a really super serious racer with a big checkbook then call someone like Braswell and have them build you a pair of carbs. But I wouldn't spend that kind of money unless I had a racepak on the car and I could tell Braswell exactly what the car is doing at each gear change going down the track.

I've dyno tested super expensive Braswell carbs back to back against the new Holley aluminum carbs and there isn't a difference on the dyno. But, that doesn't mean that a Braswell won't get you down the track faster. There is a lot of stuff going on during the gear changes and such that you don't see on the dyno.

The cross ram is a bit of an issue for carb tuners. You might have to call around a bit before you find someone who knows what works on those things. A really serious setup would require O2 bungs in each pipe. If you aren't that serious then just jet it a little rich and go have fun.

What about a pair of these for a Hemi crossram?

http://www.facebook.com/l.php?u=http%3A%2F%2Fwww.holley.com%2F0-81870&h=mAQFfwqlZ

I suggest giving Quick Fuel a call and talk to them about your combination. They are good people.