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Just have quick question, lol

mach123

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I am building a 500 stroker from a 400 block. So here is question would a Holly 750 be suitable for this build, and I am in no rush to complete it so looking for other things that are good deal new or used if would work on it, if anyone has items I should need to look for would be great. I have 727 Trans that will need to upgrade if anyone knows of a place, I'm I just moved to northern ontario. My rotating kit is the 500 kit from 440 source, I have aluminum heads already and cam and are main bolts and are head bolts. So will any suggestions of what else to watch for and where I'd would appreciate the help. Thanks
Darren
 
I think a 750 would be OK, but probably the smallest you'd want to go with. My guess is 800-850 cfm is a better choice. Maybe a stock'ish Holley/Edelbrock (Carter)...even a bigger thermoquad (maybe a little better mileage) for a cruiser engine or some aftermarket "holley type" carb if you plan to go to the track.
 
The 440s of the 70s used an 850 CFM ThermoQuad and you're looking to use 100 CFM less when you'll have 60 more cubes.
No, the 750 will not be adequate. You'll be leaving power on the table. The 850 is a bare minimum.
 
It will also depend on how you plan to drive it. If you're building a big cube engine so that it has loads of low rpm torque so you don't have to wind it all the way out to have fun, then the 750 will be fine. But if you're kissing 6,000 rpm you'll be starving for more air.
 
Maybe some @ontario guys could chime in on an engine builder
 
OP says "I'm building", that to me says he is... or has a shop already. That and Ontario is a BIG place... I have an engine builder in Smiths Falls I've known since I was 14 years old, but doubt he wants to go that far.
 
OP says "I'm building", that to me says he is... or has a shop already. That and Ontario is a BIG place... I have an engine builder in Smiths Falls I've known since I was 14 years old, but doubt he wants to go that far.
Totally agree, It's a needle in a haystack.
 
OP, the main things to consider are how you plan to use the car and what your realistic RPM limit will be. What heads & cam do you have? A small (750) carb can work well. But you would likely flatten out by 5000 RPM. All depends on what you're building. An 850 Holley would be a "normal" choice. But...
For a while I took one of the 650 DP's off my tunnel ram, put it on my single four 400/451 drag motor, 7000 RPM, big cam. It didn't slow down much. Of course, I did put the dual 650 tunnel ram back on. But I was surprised by how well the small carb worked.
 
I am running 850's on my big block strokers. I would say that is the minimum you would want to use.
 
It will also depend on how you plan to drive it.
This ^ Carburetor size varies between a street driven car,a street/race car, and a full out race car.
I ran a 750 on a 472 for drive ability as the car was street driven only.It still smoked the tires and ran like a bat out of hell.
Usually ran out of road before any need for top end speed or power.
Maybe the 750 can be a "For Now" carb. Most of the time it's a use what ya got scenario.If not then buy accordingly.
 
not sure where you are, if you go to "double R performance" site,[there in orillia area} misc. parts page they have a demon for sale $250! probably work good,but no choke,depending what your plans of use are! I was going to grab it but "500 stroker is fine with what it has on it now"
 
How far North? National Moparts is up that way. They will know engine builders. If you now go with a 750 you'll always wonder if its too small. Like many suggested an 850 is best.
 
not sure where you are, if you go to "double R performance" site,[there in orillia area} misc. parts page they have a demon for sale $250! probably work good,but no choke,depending what your plans of use are! I was going to grab it but "500 stroker is fine with what it has on it now"

I'm in cochrane ontario and lots in Timmins ontario, the only shop I'd like to find is to upgrade the 727 tranny so looking at a tranny shop, I will be using it daily driver but may go to track one day. I will need everything on engine from front cover to starter to all to water pump and so on. All I have is block bearings installed, heads, cam, rockers and rotating kit is the 500" stroker from 440source for 400 block. I have complete tranny and oil pan, rest I will need. The block I got .030 over, the heads are the e street 5090 75cc chamber and the cam is comp 21-227-4 , thx for all info
 
I don't have anything for daily, do have race block[stuffed/clearanced] for source kit!
 
Me ? Easy answer if it were my build. 6-barrel. Intakes available for the LB engine, and CFM when you need it. ( and eye-candy when you open the hood ! )
 
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I've run 750 Holleys on everything from 318's to 440's. What they are best suited for is a 340. Kind of like running stock heads that are suited for a 383 on a 500 as well. If you have it you can certainly run it but if you're going to buy a carb, buy a bigger one.
 
The smallest I have ran on a 500" (actually mild 505") was a Holley 770 cfm Ultra avenger. At the time they did not have the 870 cfm version.
I really like the old oddball Holley 1,000 HP Vac sec carb. Used it on several engines, originally my 451" B1/bs head engine, but the HP carbs don't have a choke like the avenger carbs if you live where it gets cold and don't want to hold the throttle at a fast idle till it warms up?
Right now most of my stuff is switched over to EFI.
 
The smallest I have ran on a 500" (actually mild 505") was a Holley 770 cfm Ultra avenger. At the time they did not have the 870 cfm version.
I really like the old oddball Holley 1,000 HP Vac sec carb. Used it on several engines, originally my 451" B1/bs head engine, but the HP carbs don't have a choke like the avenger carbs if you live where it gets cold and don't want to hold the throttle at a fast idle till it warms up?
Right now most of my stuff is switched over to EFI.
Well gets cold up here for sure, so your saying get one with choke then lol ok thx
 
The 440s of the 70s used an 850 CFM ThermoQuad and you're looking to use 100 CFM less when you'll have 60 more cubes.
No, the 750 will not be adequate. You'll be leaving power on the table. The 850 is a bare minimum.
TQ’s don’t flow what we call them. Look at the venturi sizes. I agree with the 850 though, no doubt.

This ^ Carburetor size varies between a street driven car,a street/race car, and a full out race car.
I ran a 750 on a 472 for drive ability as the car was street driven only.It still smoked the tires and ran like a bat out of hell.
Usually ran out of road before any need for top end speed or power.
Maybe the 750 can be a "For Now" carb. Most of the time it's a use what ya got scenario.If not then buy accordingly.
I agree with this. An 850 for his 500. Between his E-street heads and the cam @050 of 231…
 
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