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Discussion Starter #1 (Edited)







Well you guys go me thinking, and I took your advice so I got a 650DP from CL, cheap I might add, threw a 40 dollar kit, and went with the 69 primary 78 secondarys, and man what a freaking difference, the car is more responsive, seems faster, still have some final setup to do with it, it has a wee bit of a stumble on initial accelleration, and when the secondarys open, it doesnt seem right, but its worlds better than the Edelbrock 750 CFM Vac U Bog

So today ill play with squirter size, and accel pump adjustments, also went with the 6.5 PV

Btw the Speed shop I got the parts from, did the calculations and determined my engine moves 647 CFM @ 6500 RPM, so the 750 was way too much.

Now save for the Victor Jr Intake and im off to the races

Literally


Thanx tons guys

Steve
 

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650 dp

i think a 650 is plenty enough carb for a 350 until you crank in a good bit of compression, converter , and gear

i was at my buddys shop the other day ,, here comes a guy that races a fuud 302, holding a 750dp that has a proform main body. Wonders why his car won't 60ft. The 302 only has 9-1 and a 3500 converter and the car only has a 456 gear. I told him if it was me , i'd try a 650dp, 600dp or a 750 VS and see how it does. The guy laughed at me. He'll learn i guess
 

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Discussion Starter #3
Your right

i think a 650 is plenty enough carb for a 350 until you crank in a good bit of compression, converter , and gear

i was at my buddys shop the other day ,, here comes a guy that races a fuud 302, holding a 750dp that has a proform main body. Wonders why his car won't 60ft. The 302 only has 9-1 and a 3500 converter and the car only has a 456 gear. I told him if it was me , i'd try a 650dp, 600dp or a 750 VS and see how it does. The guy laughed at me. He'll learn i guess
Ive been playing wit cars for 30 years, and my carb of choice was always a 750DP, mostly big blocks, so the thought of going down to a 650 was kinda hard, the ole bigger is better theory, but she runs awesome


9.8 to 1 compression, 510 lift roller cam, alum GM Heads, and the 750 was simply too much for it


Woohoo, now she acts more like a hot rod, than a warm stick !


WS
 

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750 DP vs 650 DP for a 350 "Solved"
Where does the 750 DP come into play here? You said you went from an Edelbrock 750 VS to a Holley 650 DP. Edelbrock's are mechanical secondary carbs-with a vacuum controlled air door, like a Q-Jet. A good Q-Jet will blow away the Edelbrock in every way.
A 750 VS or DP Holley can work just fine on a mild 350 if you know what you're doing--on a street car I prefer a VS.
My buddy bolted a 750 on a stock 302 F**D in a boat--picked up 7 mph and got better mileage than the tiny Autolite carb that was on it. Spend a little time tuning, and a 750 is an excellent choice for a 350.
 

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Discussion Starter #6 (Edited)
Well you see

I HAD an Edelbrock 750 Vac
I WAS Gonna buy a Holley 750DP
It was suggested that I get a 650DP instead

So I did

The 750 Edelbrock, which seems to be a conglomeration of Carter and Weber, didnt ever run very well, no doubt too much for my tame engine.

The speed shop has a formula for Cubic inch, Cam, Compression vs CFM an engine flows at a certian RPM, He said at 6500 my engine moves 647 CFM, so a 650 is ideal. I dont hit 750 CFM until 8500 RPM, and Ill never hit that but once, LOL

It drives like a different car. Lights em up from a 20 roll ( on dry pavement ), so I'm happy for now

Thanx for your input

I like your Nova btw

Steve
 

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Discussion Starter #7
When I get my 468 Done

you could always step up a 650 by doing that too if you need more carb later on
Ill prob go with a 850 DP, but thats a long way down the road, my lil mouse is running good enough for now, so itll be a year or 2 before I build a Mousetrap
LOLOLOL


S
 

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Discussion Starter #9
Ill check the book

the 112 is correct, the 510 is correct, ill get exact specs, its a 92 ZZ350

Steve
 

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Where does the 750 DP come into play here? You said you went from an Edelbrock 750 VS to a Holley 650 DP. Edelbrock's are mechanical secondary carbs-with a vacuum controlled air door, like a Q-Jet. A good Q-Jet will blow away the Edelbrock in every way.
A 750 VS or DP Holley can work just fine on a mild 350 if you know what you're doing--on a street car I prefer a VS.
My buddy bolted a 750 on a stock 302 F**D in a boat--picked up 7 mph and got better mileage than the tiny Autolite carb that was on it. Spend a little time tuning, and a 750 is an excellent choice for a 350.
I agree hands down. I had a 600 vac sec on my first 350 in my nova and wound up going with a 3310 750 and it worked so much better it wasn't funny.
 

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604 crate engine

the 604 crate engine uses a small hyd roller , 9.8-1 , 210 runner aluminum heads , i watched my friend dyno one of 'em ,,,, he tried several carbs , it liked the tried and true , 4777 650 dp the best , even over the 650 HP version .

604 crate engines are becoming very popular around here to bring down the cost of late model dirt track racing. They allow a 750 rated carb ,,, of course no true RACER likes a 750 VS carb, but i had one in pieces i was going to put together for this dyno session to see how it would do. I bet it would have been better, but the 750 DP was a dog on that engine. They came and got the engine before i could get the carb back together ,, so we didn't get to test it and see ,,, got it ready for the next one though
 
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