Carb Question....
#1
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Carb Question....
I'm real close to buying a 87 lx coupe and it needs a new carb badly, and i was wondering what would be best. right now the car has a 351w with the original autolite carb, and i was thinking of putting a holley 750 cfm DP in its place. any thought on if this is the right way or would that be too much and i nede to step it down to a 650?
#4
RE: Carb Question....
get a 650 vacuum secondaries. get a new power valve, accelerator pump, and secondary spring kit. that will get the most power out of that carb. 750 is way to big for that engine.
#5
RE: Carb Question....
You could also get a 670cfm Street Avenger. I have the 570 on my 302 and it doesn't hurt for power anywhere, and is mild mannered and gets decent mileage. But yeah, around 625-675cfm range will cover you depending on build
#7
RE: Carb Question....
The 670 street avenger would be your best choice on that engine. If you wanted a little more then i would get a performer rpm airgap intake as well. That's the top end i would put on it.Great carb and intake for the street.I am running a 750dp on mine with heads, cam, and that intake in my windsor and still think it's a little too much.
Ryan
Ryan
#8
RE: Carb Question....
Here's why I like small carbs for the street, my car weighs about 3,000lbs and has a 26" tire with a 3.00 gear, and a 2.78 first(4 speed manual-toploader, yeah, I'm geared tall), AFR heads, 9.44:1 compression, the 570 Holleyand a cam that has a 2,000-5,500rpm range. If I putter along in first doing about 15-17mph which is just under 2,000rpm and just nail the gas to the floor in first, even with 235 wide tires and traction bars and a lockerthe tires still spin and the thing snakes up the road, and by the time they're done spinning(in about 1-2 seconds) I'm at almost 5,000rpm and getting ready to shift, with no loss in top end at all. For a race car that only ever sees high rpm a bigger carb might, MIGHT, be better, but on a street car a smaller carb will make you faster and for sure give you better throttle response
#9
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RE: Carb Question....
So, small carb for hp, but what about tq loss, will i experience much of that. the only thing im gonna be able to do for a while is new intake carb, tires and an interior rebuff. This car is an auto too. so what do i need to do. I have no idea on engine stuff, i can tell you specs all day long, but i dont know how to set up good combos.
#10
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RE: Carb Question....
and what is the secondaries thing
get a 650 vacuum secondaries. get a new power valve, accelerator pump, and secondary spring kit. that will get the most power out of that carb. 750 is way to big for that engine.