Which carb to use for 489ci?
09-02-2017, 09:33 AM
#1
Pro
Thread Starter
Which carb to use for 489ci?
Hey all!
I built a 489ci stroker and now want to put on a new carb. Right now I have the stock quadrajet, 750cfm. The new carb should be able to "feed" the extra cubes in displacement. The max. rpm are 5500-6000.
My favorites are:
So my questions are: which cfm to use, double pumper or not, and maybe another brand than Holley?
Thanks, Günther
I built a 489ci stroker and now want to put on a new carb. Right now I have the stock quadrajet, 750cfm. The new carb should be able to "feed" the extra cubes in displacement. The max. rpm are 5500-6000.
My favorites are:
- Holley street avenger 770cfm with vacuum secondaries
- Holley 850cfm with vacuum secondaries
So my questions are: which cfm to use, double pumper or not, and maybe another brand than Holley?
Thanks, Günther
09-02-2017, 10:19 AM
#2
Le Mans Master
With an automatic trans, vacuum secondary. Manual, the vacuum secondary will work, but the "feel" might be better with a mechanical secondary carb. Since you stated you're not racing, you won't have a need for being able to feed the air that a large (800cfm and above) carb would provide. The smaller carb has a higher velocity through the venturi and better low end response. The 750 cfm carb, (either the Quadrajet or the Holley) will give you a good all around response. The Holley would be a little easier to tune, given the fact that there are loads of parts available for it. Same can be done with the Quadrajet, just the parts may be a bit more difficult to find.
09-02-2017, 11:36 AM
#3
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Me...I'd use a 950 Street HP Holley. Understand that it's closer to 830 CFM...not 950 cfm.
Well, thruthfully I'd use the 1000HP if it was on my car which is larger. If it's on a dual plane intake I'd use the larger carb because each cylinder only 'see's" 2BBL's at WOT vs a single plane where each cylinder 'see's" all 4 BBL's.
A 750'ish carb will drive fine...but will be down on power as compared to something larger.
If determined to use a vacuum carb...I'd look at the Quick Fuel line at Holley and the 880 CFM version. Lots of features for the $$$. They also have nice double pumper versions...which is still what I'd use.
Stay with the "street" tuned versions. The universal versions are typically tuned fatter for racing because they have no idea what you're going to put it on. The street versions are nice. As far as mechanical secondaries and fuel usage....they only use what you tell them to with your right foot. The problem is they are so much fun we tend to play a lot more!!
JIM
Well, thruthfully I'd use the 1000HP if it was on my car which is larger. If it's on a dual plane intake I'd use the larger carb because each cylinder only 'see's" 2BBL's at WOT vs a single plane where each cylinder 'see's" all 4 BBL's.
A 750'ish carb will drive fine...but will be down on power as compared to something larger.
If determined to use a vacuum carb...I'd look at the Quick Fuel line at Holley and the 880 CFM version. Lots of features for the $$$. They also have nice double pumper versions...which is still what I'd use.
Stay with the "street" tuned versions. The universal versions are typically tuned fatter for racing because they have no idea what you're going to put it on. The street versions are nice. As far as mechanical secondaries and fuel usage....they only use what you tell them to with your right foot. The problem is they are so much fun we tend to play a lot more!!
JIM
09-02-2017, 11:56 AM
#5
Instructor
What else can you share about the engine, trans, rear gear ratio?
See above from Jim's advice - it's good. I'd say the same 950 HP Holley or a 950 QF with DP on either carb.
My $.02.
See above from Jim's advice - it's good. I'd say the same 950 HP Holley or a 950 QF with DP on either carb.
My $.02.
09-02-2017, 12:35 PM
#6
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I will add a couple of stories about some buddies of mine. One has a real nice '69 Shelby GT350 Mustang. The original engine was stored and he dropped in a 351 with ported heads, cam etc. Made just under 500 HP on the dyno. It has an auto with 3.50 gears, A/C, P/S etc.
He had a real nice Holley vacuum carb that had a ton of time involved in getting it to work REALLY well with adjustable vacuum pod, pump cam tuning etc. No issues with it. But I kept telling him he'd be real impressed with double pumper especially if we tuned it as well.
He decided to give it a try. The first time he smacked it with the 750 Holley DP his eyes got wide as the tires smoked and he felt the instant torque and pull. He swore he'd never go back and he hasn't. We never even messed with the carb after that.
In another case, I went to visit a guy I had only met through the Forum here. He had built a nice 540" for his C3 by following all the magazine recommendations. 9.0 compression so it would run on pump gas, hyd roller cam with real wide LSA for the street, dual plane intake for response, an 850 vacuum carb, small tube headers for torque, small rectangular port GM heads etc etc. I was talking to him mainly because I wanted to know how he was getting it to hook up so well. He said it just pretty much hooked and went even with the TKO 5 speed. By contrast....my 540 with a 1050 Dominator, single plane intake, way too big cylinder heads, 10.5 compression on pump gas and much larger solid roller cam would instantly go to a ditch with tire spin when I nailed it. He must be on to something right since his build was definitely geared more towards low end power than mine was.
So at our first face to face meeting, I brought him a homebuilt 850 I had done. Nothing fancy but I had converted it to 4 hole idle and some other little things, but again..very basic...but I knew it worked well.
We took a ride in his and he nailed it from a 20 mph roll. It spun the tires about 2 ft and then he nailed 2nd gear with a hard shift where it spun another foot or so. 3rd gear caused a slight tire squeal on the shift. He's like "what do you think? Cool huh?". In my mind I'm thinking how many plug wires must be off?
So we bolt on the 850 DP and go for another drive. He does same drill...nails it from a roll. The back tires light up...it starts going sideways....he steers out of it and nails 2nd gear and lights up the tires again but it's pulling like a freight train. He grabs 3rd and it's about 10 ft of black marks. His grin is about a foot wide and he just can't believe the difference in power and torque. The RPM's came up much quicker and was a heck of a lot of fun! He "borrowed" that carb for a couple of years! BTW..we also went to correcting some of the other design issues and found 100+ RWHP by letting it breathe a little.
Now...you could argue that wheel spin is not going faster...it's slower. But this was the first time he'd driven it and he had no idea it was going to happen. If there's more spinning...there's more power. You just need to control it with traction or driving ability.
I'll take power I can control with my toe any day over the rubberband feeling of vacuum secondaries. "IF" I was purely drag racing with a well setup car with slicks, I could easily make a vacuum carb work because I could tune it to open quickly and the tires could handle it. But they will also handle a double pumper. On street tires with limited traction I can easily control wheel spin with my toe. It's instant and I can feed it what it will take.
JIM
He had a real nice Holley vacuum carb that had a ton of time involved in getting it to work REALLY well with adjustable vacuum pod, pump cam tuning etc. No issues with it. But I kept telling him he'd be real impressed with double pumper especially if we tuned it as well.
He decided to give it a try. The first time he smacked it with the 750 Holley DP his eyes got wide as the tires smoked and he felt the instant torque and pull. He swore he'd never go back and he hasn't. We never even messed with the carb after that.
In another case, I went to visit a guy I had only met through the Forum here. He had built a nice 540" for his C3 by following all the magazine recommendations. 9.0 compression so it would run on pump gas, hyd roller cam with real wide LSA for the street, dual plane intake for response, an 850 vacuum carb, small tube headers for torque, small rectangular port GM heads etc etc. I was talking to him mainly because I wanted to know how he was getting it to hook up so well. He said it just pretty much hooked and went even with the TKO 5 speed. By contrast....my 540 with a 1050 Dominator, single plane intake, way too big cylinder heads, 10.5 compression on pump gas and much larger solid roller cam would instantly go to a ditch with tire spin when I nailed it. He must be on to something right since his build was definitely geared more towards low end power than mine was.
So at our first face to face meeting, I brought him a homebuilt 850 I had done. Nothing fancy but I had converted it to 4 hole idle and some other little things, but again..very basic...but I knew it worked well.
We took a ride in his and he nailed it from a 20 mph roll. It spun the tires about 2 ft and then he nailed 2nd gear with a hard shift where it spun another foot or so. 3rd gear caused a slight tire squeal on the shift. He's like "what do you think? Cool huh?". In my mind I'm thinking how many plug wires must be off?
So we bolt on the 850 DP and go for another drive. He does same drill...nails it from a roll. The back tires light up...it starts going sideways....he steers out of it and nails 2nd gear and lights up the tires again but it's pulling like a freight train. He grabs 3rd and it's about 10 ft of black marks. His grin is about a foot wide and he just can't believe the difference in power and torque. The RPM's came up much quicker and was a heck of a lot of fun! He "borrowed" that carb for a couple of years! BTW..we also went to correcting some of the other design issues and found 100+ RWHP by letting it breathe a little.
Now...you could argue that wheel spin is not going faster...it's slower. But this was the first time he'd driven it and he had no idea it was going to happen. If there's more spinning...there's more power. You just need to control it with traction or driving ability.
I'll take power I can control with my toe any day over the rubberband feeling of vacuum secondaries. "IF" I was purely drag racing with a well setup car with slicks, I could easily make a vacuum carb work because I could tune it to open quickly and the tires could handle it. But they will also handle a double pumper. On street tires with limited traction I can easily control wheel spin with my toe. It's instant and I can feed it what it will take.
JIM
09-02-2017, 12:41 PM
#7
Melting Slicks
I will add a couple of stories about some buddies of mine. One has a real nice '69 Shelby GT350 Mustang. The original engine was stored and he dropped in a 351 with ported heads, cam etc. Made just under 500 HP on the dyno. It has an auto with 3.50 gears, A/C, P/S etc.
He had a real nice Holley vacuum carb that had a ton of time involved in getting it to work REALLY well with adjustable vacuum pod, pump cam tuning etc. No issues with it. But I kept telling him he'd be real impressed with double pumper especially if we tuned it as well.
He decided to give it a try. The first time he smacked it with the 750 Holley DP his eyes got wide as the tires smoked and he felt the instant torque and pull. He swore he'd never go back and he hasn't. We never even messed with the carb after that.
In another case, I went to visit a guy I had only met through the Forum here. He had built a nice 540" for his C3 by following all the magazine recommendations. 9.0 compression so it would run on pump gas, hyd roller cam with real wide LSA for the street, dual plane intake for response, an 850 vacuum carb, small tube headers for torque, small rectangular port GM heads etc etc. I was talking to him mainly because I wanted to know how he was getting it to hook up so well. He said it just pretty much hooked and went even with the TKO 5 speed. By contrast....my 540 with a 1050 Dominator, single plane intake, way too big cylinder heads, 10.5 compression on pump gas and much larger solid roller cam would instantly go to a ditch with tire spin when I nailed it. He must be on to something right since his build was definitely geared more towards low end power than mine was.
So at our first face to face meeting, I brought him a homebuilt 850 I had done. Nothing fancy but I had converted it to 4 hole idle and some other little things, but again..very basic...but I knew it worked well.
We took a ride in his and he nailed it from a 20 mph roll. It spun the tires about 2 ft and then he nailed 2nd gear with a hard shift where it spun another foot or so. 3rd gear caused a slight tire squeal on the shift. He's like "what do you think? Cool huh?". In my mind I'm thinking how many plug wires must be off?
So we bolt on the 850 DP and go for another drive. He does same drill...nails it from a roll. The back tires light up...it starts going sideways....he steers out of it and nails 2nd gear and lights up the tires again but it's pulling like a freight train. He grabs 3rd and it's about 10 ft of black marks. His grin is about a foot wide and he just can't believe the difference in power and torque. The RPM's came up much quicker and was a heck of a lot of fun! He "borrowed" that carb for a couple of years! BTW..we also went to correcting some of the other design issues and found 100+ RWHP by letting it breathe a little.
Now...you could argue that wheel spin is not going faster...it's slower. But this was the first time he'd driven it and he had no idea it was going to happen. If there's more spinning...there's more power. You just need to control it with traction or driving ability.
I'll take power I can control with my toe any day over the rubberband feeling of vacuum secondaries. "IF" I was purely drag racing with a well setup car with slicks, I could easily make a vacuum carb work because I could tune it to open quickly and the tires could handle it. But they will also handle a double pumper. On street tires with limited traction I can easily control wheel spin with my toe. It's instant and I can feed it what it will take.
JIM
He had a real nice Holley vacuum carb that had a ton of time involved in getting it to work REALLY well with adjustable vacuum pod, pump cam tuning etc. No issues with it. But I kept telling him he'd be real impressed with double pumper especially if we tuned it as well.
He decided to give it a try. The first time he smacked it with the 750 Holley DP his eyes got wide as the tires smoked and he felt the instant torque and pull. He swore he'd never go back and he hasn't. We never even messed with the carb after that.
In another case, I went to visit a guy I had only met through the Forum here. He had built a nice 540" for his C3 by following all the magazine recommendations. 9.0 compression so it would run on pump gas, hyd roller cam with real wide LSA for the street, dual plane intake for response, an 850 vacuum carb, small tube headers for torque, small rectangular port GM heads etc etc. I was talking to him mainly because I wanted to know how he was getting it to hook up so well. He said it just pretty much hooked and went even with the TKO 5 speed. By contrast....my 540 with a 1050 Dominator, single plane intake, way too big cylinder heads, 10.5 compression on pump gas and much larger solid roller cam would instantly go to a ditch with tire spin when I nailed it. He must be on to something right since his build was definitely geared more towards low end power than mine was.
So at our first face to face meeting, I brought him a homebuilt 850 I had done. Nothing fancy but I had converted it to 4 hole idle and some other little things, but again..very basic...but I knew it worked well.
We took a ride in his and he nailed it from a 20 mph roll. It spun the tires about 2 ft and then he nailed 2nd gear with a hard shift where it spun another foot or so. 3rd gear caused a slight tire squeal on the shift. He's like "what do you think? Cool huh?". In my mind I'm thinking how many plug wires must be off?
So we bolt on the 850 DP and go for another drive. He does same drill...nails it from a roll. The back tires light up...it starts going sideways....he steers out of it and nails 2nd gear and lights up the tires again but it's pulling like a freight train. He grabs 3rd and it's about 10 ft of black marks. His grin is about a foot wide and he just can't believe the difference in power and torque. The RPM's came up much quicker and was a heck of a lot of fun! He "borrowed" that carb for a couple of years! BTW..we also went to correcting some of the other design issues and found 100+ RWHP by letting it breathe a little.
Now...you could argue that wheel spin is not going faster...it's slower. But this was the first time he'd driven it and he had no idea it was going to happen. If there's more spinning...there's more power. You just need to control it with traction or driving ability.
I'll take power I can control with my toe any day over the rubberband feeling of vacuum secondaries. "IF" I was purely drag racing with a well setup car with slicks, I could easily make a vacuum carb work because I could tune it to open quickly and the tires could handle it. But they will also handle a double pumper. On street tires with limited traction I can easily control wheel spin with my toe. It's instant and I can feed it what it will take.
JIM
Jim's experiences mimic mine exactly!Mike
09-02-2017, 12:52 PM
#8
Drifting
Me...I'd use a 950 Street HP Holley. Understand that it's closer to 830 CFM...not 950 cfm.
Well, thruthfully I'd use the 1000HP if it was on my car which is larger. If it's on a dual plane intake I'd use the larger carb because each cylinder only 'see's" 2BBL's at WOT vs a single plane where each cylinder 'see's" all 4 BBL's.
A 750'ish carb will drive fine...but will be down on power as compared to something larger.
If determined to use a vacuum carb...I'd look at the Quick Fuel line at Holley and the 880 CFM version. Lots of features for the $$$. They also have nice double pumper versions...which is still what I'd use.
Stay with the "street" tuned versions. The universal versions are typically tuned fatter for racing because they have no idea what you're going to put it on. The street versions are nice. As far as mechanical secondaries and fuel usage....they only use what you tell them to with your right foot. The problem is they are so much fun we tend to play a lot more!!
JIM
Well, thruthfully I'd use the 1000HP if it was on my car which is larger. If it's on a dual plane intake I'd use the larger carb because each cylinder only 'see's" 2BBL's at WOT vs a single plane where each cylinder 'see's" all 4 BBL's.
A 750'ish carb will drive fine...but will be down on power as compared to something larger.
If determined to use a vacuum carb...I'd look at the Quick Fuel line at Holley and the 880 CFM version. Lots of features for the $$$. They also have nice double pumper versions...which is still what I'd use.
Stay with the "street" tuned versions. The universal versions are typically tuned fatter for racing because they have no idea what you're going to put it on. The street versions are nice. As far as mechanical secondaries and fuel usage....they only use what you tell them to with your right foot. The problem is they are so much fun we tend to play a lot more!!
JIM
09-02-2017, 01:34 PM
#10
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I would get the Holley HP Street 950. It's actually not 950 cfm. Good carb. It's really a combination of an 850 and a 750. Closer to 830 cfm. Large throttle plates and smaller venturis make it responsive.
The generic 850 DP's will be tuned a little fat for what you need.
JIM
The generic 850 DP's will be tuned a little fat for what you need.
JIM
09-02-2017, 01:45 PM
#11
Team Owner
Member Since: Oct 2004
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St. Jude Donor '05
x3 Jim
a well tuned 650 DP made way more power than any 750 vs I had on a former 350 no matter what I did. will never go back to vs again (heavy car with an automatic and 3.08 gear, too!)
From basketball throttle response to razor sharp/tire smoke.
Doesnt make sense "on paper" but they work if set up right.
a well tuned 650 DP made way more power than any 750 vs I had on a former 350 no matter what I did. will never go back to vs again (heavy car with an automatic and 3.08 gear, too!)
From basketball throttle response to razor sharp/tire smoke.
Doesnt make sense "on paper" but they work if set up right.
09-02-2017, 08:38 PM
#12
Le Mans Master
I agree with Jim , double pumpers work. I've heard the old line the horsepower is the same, the fact is the response is vastly better.
I had a buddy back in 78 that had a new pace car with an automatic and he complained about his L-82 was a dog and couldn't spin a tire. I curved his distributor and put a Holley double pumper q jet replacement on it and he complained he wouldn't be able to afford tires.
I had a buddy back in 78 that had a new pace car with an automatic and he complained about his L-82 was a dog and couldn't spin a tire. I curved his distributor and put a Holley double pumper q jet replacement on it and he complained he wouldn't be able to afford tires.
09-02-2017, 09:16 PM
#13
Instructor
Gunther - My car for example for a comparison:
496, 4 spd, 3.08 gear ratio, pancake LS6 intake (Low rise).
I have a Quick fuel Q-1050-AN on mine. So a 1050 double pumper/mechanical secondaries. It probably flows in the 900 CFM area as a guess (Someone can correct me)
It has VERY fast/quick throttle response, no bog, no delay just clean power.
Look at the Holley 950 HP street Jim has mentioned or the QFT 950 Street version.
My $.02
496, 4 spd, 3.08 gear ratio, pancake LS6 intake (Low rise).
I have a Quick fuel Q-1050-AN on mine. So a 1050 double pumper/mechanical secondaries. It probably flows in the 900 CFM area as a guess (Someone can correct me)
It has VERY fast/quick throttle response, no bog, no delay just clean power.
Look at the Holley 950 HP street Jim has mentioned or the QFT 950 Street version.
My $.02
09-03-2017, 03:21 AM
#14
Pro
Thread Starter
Thank you all!
I will look up for the Holley 950 HP street Jim has mentioned or the QFT 950 Street version.
Maybe anybody has one for sale?
I will look up for the Holley 950 HP street Jim has mentioned or the QFT 950 Street version.
Maybe anybody has one for sale?
Last edited by Günther-C3; 09-03-2017 at 03:22 AM.
09-03-2017, 12:45 PM
#15
Race Director
I've been following this thread and a lot of excellent info included. As most of you have read, I'm building my inventory of parts and I'm now pulling together the parts for my motor. I'll be stroking my 454 to 496 ci, running about 10.5.:1, edelbrock oval port heads, RPM air gap, etc. Doing the calculations, it seems this carb will be perfect for my use at a true 830cfm. What do you think? And you are referring to the Holley 0- 82951 hp street 950? Ill be running an OD auto trans with 3:36 gears. Would you recommend the zinc or aluminum body?
Last edited by OldCarBum; 09-06-2017 at 11:09 AM.
09-04-2017, 12:44 AM
#16
Burning Brakes
Thank goodness "too broke" is not here anymore. I Traded my 670 Holley street avenger, with the yellow spring installed, for a Holley 650 street HP and the difference was night and day. No more vacuum secondaries for me.
09-04-2017, 12:16 PM
#17
Safety Car
Another option for a great carburetor matched to your car.
I have a 1968 L-71 car with a stoutly built 427 running very high compression and making a bunch of horsepower.
I played with the different carburetors while in my learning curve. I have a collection in my garage of former carburetors. I really liked the performance of the Holley 750 Double Pumper on my car and used it most often. It had the most bang for the buck so to speak.
I knew that the 750 did not flow enough air for my combination but the smaller size made it respond better on the road.
One thing that you will want is the electric choke function over in Europe. That is an important feature that you will need.
I learned of a company here in Virginia who buys Holley Carburetor bodies and machines them in their facility. This company is called AED Performance. They build some of the best carburetors I have ever used. Here is the link:
http://www.aedperformance.com/
The representative of the company and I spoke for close to an hour and then he told me what he thought they could do for me. He knew every detail about my engine and recommended a unique combination carburetor for my car. I have the high flow of air I need and the snappy response.
I love my AED Performance Carburetor! My old Holley 750 double pumper is now a back-up carburetor as is the Edlebrock Performer 750 and the Speed Demon 850 on my shelf.
The owner of the company and I spoke about the setup, he assured me that all I would have to do is "Bolt it on" as the carburetors setup would have been done at their facility. He was 100% right, this carburetor has worked for me since the day I put it on.
The owner also told me that if I had any problems at all that he would put my car on a dyno and set it up again with me present.
Look at their website before you spend your hard earned money. This company is a great option to ordering just a plain old carburetor from a mail order shop. Summit carries their carbs and rebuild kits as well but speak with the people at AED before you order something.
I wish you the very best in finding the solution that makes your car the happiest!
I played with the different carburetors while in my learning curve. I have a collection in my garage of former carburetors. I really liked the performance of the Holley 750 Double Pumper on my car and used it most often. It had the most bang for the buck so to speak.
I knew that the 750 did not flow enough air for my combination but the smaller size made it respond better on the road.
One thing that you will want is the electric choke function over in Europe. That is an important feature that you will need.
I learned of a company here in Virginia who buys Holley Carburetor bodies and machines them in their facility. This company is called AED Performance. They build some of the best carburetors I have ever used. Here is the link:
http://www.aedperformance.com/
The representative of the company and I spoke for close to an hour and then he told me what he thought they could do for me. He knew every detail about my engine and recommended a unique combination carburetor for my car. I have the high flow of air I need and the snappy response.
I love my AED Performance Carburetor! My old Holley 750 double pumper is now a back-up carburetor as is the Edlebrock Performer 750 and the Speed Demon 850 on my shelf.
The owner of the company and I spoke about the setup, he assured me that all I would have to do is "Bolt it on" as the carburetors setup would have been done at their facility. He was 100% right, this carburetor has worked for me since the day I put it on.
The owner also told me that if I had any problems at all that he would put my car on a dyno and set it up again with me present.
Look at their website before you spend your hard earned money. This company is a great option to ordering just a plain old carburetor from a mail order shop. Summit carries their carbs and rebuild kits as well but speak with the people at AED before you order something.
I wish you the very best in finding the solution that makes your car the happiest!
09-04-2017, 12:37 PM
#18
Le Mans Master
Member Since: Oct 2002
Location: Las Vegas - Just stop perpetuating myths please.
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Hey all!
I built a 489ci stroker and now want to put on a new carb. Right now I have the stock quadrajet, 750cfm. The new carb should be able to "feed" the extra cubes in displacement. The max. rpm are 5500-6000.
My favorites are:
So my questions are: which cfm to use, double pumper or not, and maybe another brand than Holley?
Thanks, Günther
I built a 489ci stroker and now want to put on a new carb. Right now I have the stock quadrajet, 750cfm. The new carb should be able to "feed" the extra cubes in displacement. The max. rpm are 5500-6000.
My favorites are:
- Holley street avenger 770cfm with vacuum secondaries
- Holley 850cfm with vacuum secondaries
So my questions are: which cfm to use, double pumper or not, and maybe another brand than Holley?
Thanks, Günther
Maybe too small for what you want but I have at least 2 rebuildable 800cfm q-jet cores w/electric choke. They diffinantly need a rebuild though - they need the lars magic touch. At least one has PTA. You can PM if interested.
Good luck.
Last edited by cardo0; 09-04-2017 at 12:38 PM. Reason: Space a word.
09-04-2017, 08:45 PM
#19
Drifting
I have a 1968 L-71 car with a stoutly built 427 running very high compression and making a bunch of horsepower.
I played with the different carburetors while in my learning curve. I have a collection in my garage of former carburetors. I really liked the performance of the Holley 750 Double Pumper on my car and used it most often. It had the most bang for the buck so to speak.
I knew that the 750 did not flow enough air for my combination but the smaller size made it respond better on the road.
One thing that you will want is the electric choke function over in Europe. That is an important feature that you will need.
I learned of a company here in Virginia who buys Holley Carburetor bodies and machines them in their facility. This company is called AED Performance. They build some of the best carburetors I have ever used. Here is the link:
http://www.aedperformance.com/
The representative of the company and I spoke for close to an hour and then he told me what he thought they could do for me. He knew every detail about my engine and recommended a unique combination carburetor for my car. I have the high flow of air I need and the snappy response.
I love my AED Performance Carburetor! My old Holley 750 double pumper is now a back-up carburetor as is the Edlebrock Performer 750 and the Speed Demon 850 on my shelf.
The owner of the company and I spoke about the setup, he assured me that all I would have to do is "Bolt it on" as the carburetors setup would have been done at their facility. He was 100% right, this carburetor has worked for me since the day I put it on.
The owner also told me that if I had any problems at all that he would put my car on a dyno and set it up again with me present.
Look at their website before you spend your hard earned money. This company is a great option to ordering just a plain old carburetor from a mail order shop. Summit carries their carbs and rebuild kits as well but speak with the people at AED before you order something.
I wish you the very best in finding the solution that makes your car the happiest!
I played with the different carburetors while in my learning curve. I have a collection in my garage of former carburetors. I really liked the performance of the Holley 750 Double Pumper on my car and used it most often. It had the most bang for the buck so to speak.
I knew that the 750 did not flow enough air for my combination but the smaller size made it respond better on the road.
One thing that you will want is the electric choke function over in Europe. That is an important feature that you will need.
I learned of a company here in Virginia who buys Holley Carburetor bodies and machines them in their facility. This company is called AED Performance. They build some of the best carburetors I have ever used. Here is the link:
http://www.aedperformance.com/
The representative of the company and I spoke for close to an hour and then he told me what he thought they could do for me. He knew every detail about my engine and recommended a unique combination carburetor for my car. I have the high flow of air I need and the snappy response.
I love my AED Performance Carburetor! My old Holley 750 double pumper is now a back-up carburetor as is the Edlebrock Performer 750 and the Speed Demon 850 on my shelf.
The owner of the company and I spoke about the setup, he assured me that all I would have to do is "Bolt it on" as the carburetors setup would have been done at their facility. He was 100% right, this carburetor has worked for me since the day I put it on.
The owner also told me that if I had any problems at all that he would put my car on a dyno and set it up again with me present.
Look at their website before you spend your hard earned money. This company is a great option to ordering just a plain old carburetor from a mail order shop. Summit carries their carbs and rebuild kits as well but speak with the people at AED before you order something.
I wish you the very best in finding the solution that makes your car the happiest!
Last edited by roscobbc; 09-04-2017 at 08:47 PM.
09-05-2017, 05:35 PM
#20
Burning Brakes
I have connection with custom carburetor builder who build a quick fuel specifically for your build. He is very reasonable on price and all the feedback I have received is good. I know at least 10 circle track guys that are very pleased with his carburetors. I have a 950 double pumper with annular boosters on my build. If interested send pm and I will give you contact information.
Dave
Dave