I have a 383 stroker in a 2800 lb. car with a 750 Quick Fuel carb.Sec(High speed air 33-idle air70-primary sqt. 31-second-42 primary jet 84-sec-92 and a 3.5 vac. and the back is blank.) My question is a have a chance to get a Pro Systems 850 and a 950. Do you think any of these will help me?
November 28, 2022, 04:52 PM
Goob
Only one way to tell.
Is the carb you have running well, or do you have problems? I didn't see much difference, if any between a BG 750 and a box Holley 850 on my 3200# 406 combo. I only run the 850 because it's a 4 corner idle circuit unit.
If your 750 is as good as it can be, you won't see much difference, although a lighter car like yours will accept more carburetor easily.
"Despite the high cost of living, it remains popular." Dave Cook N375
November 28, 2022, 07:47 PM
1320racer
Go with the Pro systems 950.
November 29, 2022, 10:27 AM
Eman
84 and 92 jets? That seems like a lot in a 750. Usually the primary squirter is larger, are you footbraking? Is there a problem or are you wanting et improvement?
November 29, 2022, 02:34 PM
TOP38
quote:
Originally posted by racerbug: I have a 383 stroker in a 2800 lb. car with a 750 Quick Fuel carb.Sec(High speed air 33-idle air70-primary sqt. 31-second-42 primary jet 84-sec-92 and a 3.5 vac. and the back is blank.) My question is a have a chance to get a Pro Systems 850 and a 950. Do you think any of these will help me?
First assuming there is nothing wrong with your current carb and it's tuned to match what the motor wants, if you are making more than 550 HP then a larger carb with provide more HP. The 850 up to 650HP and the 950 up to 725HP. Those power number don't mean you can't make more HP with them, just when they will start to hurt peak HP. A heavy car with a lower HP motor, usually a smaller carb will perform better on track than one sized for max peak power!
November 29, 2022, 02:42 PM
racerbug
To answer some questions. It is in a no box car I do have a 2 step. The engine shop that helped me with the engine thinks it should be around 620 hp.I think the 750 is as good as it can get that is why I was looking to go to a bigger carb. But then I would have to start all over with the set up.
November 29, 2022, 02:47 PM
Curly1
If you have enough rear gear and stall converter it will go faster with larger car.
https://postimg.cc/gallery/np3zpruo/ "Dunning-Kruger Effect" -a type of Cognitive bias where people with little expertise or ability assume they have superior expertise or ability. This overestimation occurs as a result of the fact that they do not have enough knowledge to know they don't have enough knowledge.
Before you argue with someone ask yourself, "Is this person mentally mature enough to grasp the concept of a different perspective?" If not there is no point to argue.
4X NE2 CHAMPION. 2020 TDRA NE2 Champion
November 29, 2022, 02:53 PM
1320racer
just for clarification, the 950 is smaller than the 850 but larger than a 750 due to using the 850's 1 3/4" bore baseplate.
November 29, 2022, 02:56 PM
TOP38
quote:
Originally posted by racerbug: To answer some questions. It is in a no box car I do have a 2 step. The engine shop that helped me with the engine thinks it should be around 620 hp.I think the 750 is as good as it can get that is why I was looking to go to a bigger carb. But then I would have to start all over with the set up.
What the car run in the 1/4 or 1/8 and MPH
November 30, 2022, 08:37 AM
Brktracer
Very doubtful to see more than .01 to .02 difference between all those carbs.
Matt Ward
November 30, 2022, 02:14 PM
FootbrakeJim
My old 3600 # footbrake car picked up a good bit when I went from a 750 to an 850. Around 2 tenths and 3 MPH. It was a moderate 408 inch BBC with steel oval port heads, solid flat-tappet cam, only pushed 447 HP with the 750. Did not dyno it with the 850. It did require more fuel with the bigger carb, had to re-plumb the lines and add a bigger pump. The short times were immediately better, but it nosed over around 1000 Ft until I fed it better.
Dan "Jim" Moore Much too young to feel this damn old!!
December 01, 2022, 05:04 PM
racerbug
First I would like to thank you all for you input. The reason I am being a pain is the track I raced at was 20 min. away. now I have to go 2.5 south- 2.5 north and 4.5 north west. I am not a carb guru. Like you guys So I need all the help I can get. My car runs 6.50 at 105.75in the 8th.-and 10.38 at 130.83.with the set-up on the 750. If I change to the bigger carbs where do I start? Again thank you all for any input that can help.
December 02, 2022, 08:56 AM
1320racer
again...
quote:
Originally posted by 1320racer: Go with the Pro systems 950.
with the as built jetting.
December 02, 2022, 10:26 AM
Eman
What does your car weigh? 6.50's with 620 HP the car must be heavy. I'd work on getting it to run with what you have. What fuel are you running? Ever thought of going to methanol or E85?
December 02, 2022, 10:41 AM
1320racer
quote:
Originally posted by racerbug: I have a 383 stroker in a 2800 lb. car with a 750 Quick Fuel carb.Sec
December 02, 2022, 04:03 PM
Wooley
If the car truly is 2800 pounds I don’t think the engine actually has 620 fw horsepower. The math just doesn’t work.
December 02, 2022, 04:26 PM
Mike Rietow
quote:
Originally posted by racerbug: First I would like to thank you all for you input. The reason I am being a pain is the track I raced at was 20 min. away. now I have to go 2.5 south- 2.5 north and 4.5 north west. I am not a carb guru. Like you guys So I need all the help I can get. My car runs 6.50 at 105.75in the 8th.-and 10.38 at 130.83.with the set-up on the 750. If I change to the bigger carbs where do I start? Again thank you all for any input that can help.
Your west palm racer buddies were at Orlando last race, Orlando had 400 cars show up for a local.
Packed, rained off and on Orlando crew didn't disappoint, finished up Sunday after racing till 1 am.
That's your new home track.
Sounds like a half decent sbc, I wouldn't be afraid to try the 950.
750 sounds alright too.
December 04, 2022, 10:07 AM
HR3377
I would try leaning it out about 2-4 jet sizes first it cost nothing and you seem to have Alot of jetting in it now I have a 406 with an 800 and don't run that much jetting.
December 04, 2022, 10:33 AM
B KING
I don't know what QF carb the OP has, but I looked at the specs for 2 different 750 QF carbs on their web site. Both list Pri. jets at 74 & Sec jets at 84 with primary PV only.
The 750 E85 QF carb list Pri. jets at 80 & Sec. jets at 90, just for reference.
2BKing
1980 Camaro Taking the Best Working Small Tire Shyt Box & making it Greater Than Before! 3000 lbs. Pump Gas 436
December 04, 2022, 10:57 AM
Mike Rietow
quote:
Originally posted by HR3377: I would try leaning it out about 2-4 jet sizes first it cost nothing and you seem to have Alot of jetting in it now I have a 406 with an 800 and don't run that much jetting.
Bigger engines take smaller jets, smaller engines take bigger jets - signal.
I would go to the track and have a good time win, lose or draw, testing and learning drag racing on my own terms, with whatever carb I felt was best.
No pain no gain.This message has been edited. Last edited by: Mike Rietow,