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Discussion Starter #21
I built a351C with the same cam, 3000 stall, C6, 3.50 gears and I always have 3 or 4 Holley carbs laying around. What I have found is that they like a bigger carb then say a 351 W. I found a 780 worked good, But I like double pumpers and 750 worked great.
Ok thanks, like you most people are saying go for the 750cfm.
When you built the 351c did you block the exhaust heat cross overs off, & does it need the turkey pan when using the edelbrock torker intake.
 

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Depends on a lot more than you've posted, but if it's spaghetti on the wall you want, it's spaghetti on the wall you get.

For me, a Holley 750 double pump - mechanical secondaries. My right foot knows where the secondaries come in, it's not an on/off switch.

FWIW, 265 at the wheels with the equipment you describe is awfully low.
Im new to the game, but wouldnt your carb selection vary dependent on what you are using the car for. Is this a track car or or street car? However the think the general consensus is for that car you could go with a 750. But a lot of people over carb their engines. IJS
Were getting there but need a little more information to do this right:

  • What redline are you thinking e.g. do you have a chip or when will you pull your foot?
  • How often will your car be approaching redline?
  • How important is it to you that your car be strong in the high RPMs?
  • Would you prefer a stronger midrange performance, I'm not an auto guy but isn't a 2800 stall converter more of a mid-range street pounder type of application as oppsoed to hard core drag strip?
  • How important is midrange throttle response?
  • How will you use your car, daily driver, fun car but want to make good times at the drags, fun car autocrosser, serious anything? How do you drive your car, when you picture yourself smiling behind the wheel, what are you doing (while driving ;o))
  • What mods do you plan in the near future?
If your a 6-6500k kinda redline guy who wants a fun street car that has good throttle response, I would stick to 650 CFM. IF the drag strip is your thing STOMP n GO, you can go up to a 750. The original Torker is a 2500-6500 RPM range, if your cam is matched, you can do either, its just where you want your power and how much mid range throttle response you want. I run a 650 DP that has great throttle response, but with an auto, folks like vacuum secondaries. likely more appropriate for street driving.

I did a previous rant on carbs here
 

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65 Fastback 289 4 spd, 65 convertible 5.0L 5 spd. 3.73 8.8
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Were getting there but need a little more information to do this right:

  • What redline are you thinking e.g. do you have a chip or when will you pull your foot?
  • How often will your car be approaching redline?
  • How important is it to you that your car be strong in the high RPMs?
  • Would you prefer a stronger midrange performance, I'm not an auto guy but isn't a 2800 stall converter more of a mid-range street pounder type of application as oppsoed to hard core drag strip?
  • How important is midrange throttle response?
  • How will you use your car, daily driver, fun car but want to make good times at the drags, fun car autocrosser, serious anything? How do you drive your car, when you picture yourself smiling behind the wheel, what are you doing (while driving ;o))
  • What mods do you plan in the near future?
If your a 6-6500k kinda redline guy who wants a fun street car that has good throttle response, I would stick to 650 CFM. IF the drag strip is your thing STOMP n GO, you can go up to a 750. The original Torker is a 2500-6500 RPM range, if your cam is matched, you can do either, its just where you want your power and how much mid range throttle response you want. I run a 650 DP that has great throttle response, but with an auto, folks like vacuum secondaries. likely more appropriate for street driving.

I did a previous rant on carbs here
Clevlands need a bigger carb, they don't run as good with small carbs. I also have a Chevelle that has a 377 with a 280 comp cam, Victor Jr., 3000 stall 3.73 gears and I run a 650 spread bore, that turns 6900 rpms, and it has great throttle respose.
 

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65 Fastback 289 4 spd, 65 convertible 5.0L 5 spd. 3.73 8.8
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Ok thanks, like you most people are saying go for the 750cfm.
When you built the 351c did you block the exhaust heat cross overs off, & does it need the turkey pan when using the edelbrock torker intake.
I blocked the EGR and I ran the pan,
 

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Belky, alot of the thing with carbs is what kind of boosters does it have ? The Holleys and the Autolites that the factory gave us had annular discharge boosters. GM and Chryslers didn't get annular booster carbs because it was a Ford idea and they (Ford) had a patent on the design, and others didn't want to pay royalties to Ford. Now that those patents are long expired, you can get a carb however you want. What does the 750 have, and what does the 650 have ? I would say run the 650 and see if you like it better than the 750. You own both now, right ?

I would run the turkey pan, but trim it so that you are using only the center section to keep hot oil off from the bottom of the intake. Get composition gaskets to seal the ports. Whether you leave the cross over open or not depends on where you drive and what the temperatures are like, and what ignition do you have ? The crossover is to help the engine get warm faster and to ensure that you don't have any fuel puddling in the intake. If you have a healthy enough ignition, and run a faily wide gap, it frequently is enough to run well, even if the engine is cold.

On the intake and cam, what you have will work fine, but you can definately improve the performance for street driving, and even most drag racing, if you chose a smaller and wider camshaft, and a dual plane intake, like the Blue Thunder. The large port Clevelands are especially sensitive to camshaft choice, and most folks don't know how to do it, and most Clevelands could easily be dramatically improved with a different cam from what they have , yours is no different.


LSG
 

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My 2 cents... keep the 650 Edelbrock and put on a Dual Plane intake!!! A Torker is meant for one thing, racing!!!!!!
 

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Ford Mustang fastback GT390
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Discussion Starter #27
Belky, alot of the thing with carbs is what kind of boosters does it have ? The Holleys and the Autolites that the factory gave us had annular discharge boosters. GM and Chryslers didn't get annular booster carbs because it was a Ford idea and they (Ford) had a patent on the design, and others didn't want to pay royalties to Ford. Now that those patents are long expired, you can get a carb however you want. What does the 750 have, and what does the 650 have ? I would say run the 650 and see if you like it better than the 750. You own both now, right ?

I would run the turkey pan, but trim it so that you are using only the center section to keep hot oil off from the bottom of the intake. Get composition gaskets to seal the ports. Whether you leave the cross over open or not depends on where you drive and what the temperatures are like, and what ignition do you have ? The crossover is to help the engine get warm faster and to ensure that you don't have any fuel puddling in the intake. If you have a healthy enough ignition, and run a faily wide gap, it frequently is enough to run well, even if the engine is cold.

On the intake and cam, what you have will work fine, but you can definately improve the performance for street driving, and even most drag racing, if you chose a smaller and wider camshaft, and a dual plane intake, like the Blue Thunder. The large port Clevelands are especially sensitive to camshaft choice, and most folks don't know how to do it, and most Clevelands could easily be dramatically improved with a different cam from what they have , yours is no different.

LSG
Belky, alot of the thing with carbs is what kind of boosters does it have ? The Holleys and the Autolites that the factory gave us had annular discharge boosters. GM and Chryslers didn't get annular booster carbs because it was a Ford idea and they (Ford) had a patent on the design, and others didn't want to pay royalties to Ford. Now that those patents are long expired, you can get a carb however you want. What does the 750 have, and what does the 650 have ? I would say run the 650 and see if you like it better than the 750. You own both now, right ?

I would run the turkey pan, but trim it so that you are using only the center section to keep hot oil off from the bottom of the intake. Get composition gaskets to seal the ports. Whether you leave the cross over open or not depends on where you drive and what the temperatures are like, and what ignition do you have ? The crossover is to help the engine get warm faster and to ensure that you don't have any fuel puddling in the intake. If you have a healthy enough ignition, and run a faily wide gap, it frequently is enough to run well, even if the engine is cold.

On the intake and cam, what you have will work fine, but you can definately improve the performance for street driving, and even most drag racing, if you chose a smaller and wider camshaft, and a dual plane intake, like the Blue Thunder. The large port Clevelands are especially sensitive to camshaft choice, and most folks don't know how to do it, and most Clevelands could easily be dramatically improved with a different cam from what they have , yours is no different.


LSG
My next move is to put the intake back on, i have a set of gaskets from Mr Gasket, (never used these) which are slightly thicker then what i normally have, with the cork end pieces, would you sill use rtv on all the gaskets & end pieces?.
Then i'm going to throw the Holley 4160 750 CFM on,this came on the car when i bought it 2 years ago, which came with quite a few issues, blown head gasket/ rotten fuel lines, this that & the other, so i ended chucking the toys out of the pram & basically bought all new. but i must admit with the holley on it was quicker & more responsive. what kinda difference would i see if i went for the blue thunder intake.
What MPG do you get out of your 351c's, with the holley 750 on mine average 7-8 MPG, edelbrock AVS2 650CFM 10-11 MPG.
 

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I have a stroked 351C with full roller with around 500 hp c/w trick flow heads. I tried several carbs three of which were edelbrock, 750, 650, 500. I could not get rid of a flat spot with the 750 which seemed correct but I felt that there was more there. I tune with exhaust gas monitors right after the headers. The edelbrocks had one full season of testing. I then went to a SS780 quick fuel and right out of the box the car was a animal, jetted down two on primary's and one on the secondary's car was very strong and very responsive. I believe edelbrocks are a decent stock replacement carb but not a performance carb. I have awakened several friends motors with a switch and tune going to quick fuel. If you are stockish go with 650/680 quick fuel vac secondarys.
748959
 

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what kinda difference would i see if i went for the blue thunder intake.
Hard to say without knowing what's in the engine. The BT intake is known to be an excellent all around performer and provides better high end power than some single planes.


What MPG do you get out of your 351c's, with the holley 750 on mine average 7-8 MPG, edelbrock AVS2 650CFM 10-11 MPG.
All depends on how it's tuned, transmission, rear gear and driving style. First 351C-4V I built would nail down 20mpg on the highway with 3.00 rear gears and that was with an 800DP.

I built a second a couple years later, almost the exact same and it would average 18mpg with 3.25s, then went to 12mpg when I put the 3.89s in.

My third was a conglomeration of used parts to make a stock 71 M-code engine with a Comp 280H cam in a Cougar with 3.25 gears and a 4 speed. I initially ran the factory Autolite 4300 with crap results - 8mpg. After a couple weeks of troubleshooting, testing, tuning and rebuilding, I put that POs on the shelf and bolted on a 750DP and immediately went to 14mpg. I then tossed the factory flex fan and bolted on a clutched unit and went to 16mpg.

I've always felt that MPG was an excellent indicator of how well tuned your engine was, just like BSFC readings on a dyno.
 
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