Holley 650DP or Demon 650DP
10-27-2003, 02:29 PM
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Car: '82 Z28
Engine: 350HO
Transmission: M4
Holley 650DP or Demon 650DP
right now im running an edelbrock 1405, and while the motor seems to run well on the street, i think a holley style carb will be better suited for the motor.
i really only want to upgrade carbs once.
i know that demons are almost identical to holley's. so i was wondering if there is much of a gain from a holley 650DP to a speed demon 650DP.
im leaning towards the holley, because of the $100 dollar difference.
but if the demon is that much better, i might be able to justify the price.
i really only want to upgrade carbs once.
i know that demons are almost identical to holley's. so i was wondering if there is much of a gain from a holley 650DP to a speed demon 650DP.
im leaning towards the holley, because of the $100 dollar difference.
but if the demon is that much better, i might be able to justify the price.
10-27-2003, 06:11 PM
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
I've known of exactly one person who tried a Demon and didn't like it. He had a Carter AFB, tried a Demon at a test & tune, didn't know how to tune it (not even sure it was the right size for his engine), went back to the Carter.
Otherwise, I've seen a lot of guys going to the Demons with no complaints.
Otherwise, I've seen a lot of guys going to the Demons with no complaints.
10-27-2003, 08:24 PM
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Car: '82 Z28
Engine: 350
Transmission: TH400 4,000 stall
Axle/Gears: Currie 9", 4.56 gears
No complaints about my Demon 
I switched from a Holley 670 to a Speed Demon 750 dp. Great throttle response, 20-22 mpg on the highway and looks cool 
I switched from a Holley 670 to a Speed Demon 750 dp. Great throttle response, 20-22 mpg on the highway and looks cool
10-28-2003, 06:28 PM
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Originally posted by EvilCartman
No complaints about my Demon I switched from a Holley 670 to a Speed Demon 750 dp. Great throttle response, 20-22 mpg on the highway and looks cool
No complaints about my Demon
I switched from a Holley 670 to a Speed Demon 750 dp. Great throttle response, 20-22 mpg on the highway and looks cool I hope you are slowly buying parts for a new engine... or it fell off a truck or something.
10-28-2003, 08:51 PM
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Car: '82 Z28
Engine: 350
Transmission: TH400 4,000 stall
Axle/Gears: Currie 9", 4.56 gears
hehehe new engine would be done this week but found out monday the block I gave him was cracked 
Oh well, it was only 50 bucks. The 750 dp actually works damn good on my 305. Really suprised the hell out of me when I put it on the first time just to see what would happen. Worked so good, I left the Holley 670 off it and that's going up on ebay tonight.
Oh well, it was only 50 bucks. The 750 dp actually works damn good on my 305. Really suprised the hell out of me when I put it on the first time just to see what would happen. Worked so good, I left the Holley 670 off it and that's going up on ebay tonight.
10-29-2003, 01:46 PM
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Car: 2000 astro
Engine: 4.3
Transmission: A4
Axle/Gears: 7.5 with 3.42 gears
cartman...
weird... the 750 dp runs well on your 305? i'm considering rebuilding an existing holley that i have, or saving up and buying a new carb.
i can get a decent deal on the street avenger carbs through work, but i'm thinking i want a mechanical secondary carb for my manual transmission equipped car.
i want to build a 350 possibly over the winter, but i'm not sure what size carb to run on it..... the catch is i need this carb to run well on my 305 that i have for now...
i'm pretty sure i don't need a 750, i'm thinking a 650 would work well for me. feedback?
weird... the 750 dp runs well on your 305? i'm considering rebuilding an existing holley that i have, or saving up and buying a new carb.
i can get a decent deal on the street avenger carbs through work, but i'm thinking i want a mechanical secondary carb for my manual transmission equipped car.
i want to build a 350 possibly over the winter, but i'm not sure what size carb to run on it..... the catch is i need this carb to run well on my 305 that i have for now...
i'm pretty sure i don't need a 750, i'm thinking a 650 would work well for me. feedback?
10-29-2003, 08:45 PM
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Car: '82 Z28
Engine: 350
Transmission: TH400 4,000 stall
Axle/Gears: Currie 9", 4.56 gears
I'd say go with a 650 DP then later on if you need more, get a proform main body. btw, the 305 is coming out this weekend sold it today for 300 bucks 
Should have asked for more to see what the guy said LOL. Ah well, it's sold... getting the cash next week when he comes and gets it.
sold it today for 300 bucks Should have asked for more to see what the guy said LOL. Ah well, it's sold... getting the cash next week when he comes and gets it. Trending Topics
10-31-2003, 08:35 PM
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Car: 1988 trans am
Engine: 5.7 gm H.O. crate engine
Transmission: 700r4
i have a holly 650 dp mechanical secondaries (700r4) and it works flawlessly. i didnt change andything to it just bolted it on and went. works perfect for my 350 h.o. crate engine. my .02
11-02-2003, 03:01 PM
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Car: 89' T/A, 00' Firehawk
Engine: 406 Roller
Transmission: TH700R4 w/2800 stall
Axle/Gears: 3.23 Posi
Originally posted by cr125r
i have a holly 650 dp mechanical secondaries (700r4) and it works flawlessly. i didnt change andything to it just bolted it on and went. works perfect for my 350 h.o. crate engine. my .02
i have a holly 650 dp mechanical secondaries (700r4) and it works flawlessly. i didnt change andything to it just bolted it on and went. works perfect for my 350 h.o. crate engine. my .02
Jason
11-02-2003, 04:41 PM
#10
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Keep the carb you have. You're not going to see much gain from going to a 650 from a 600.
A double pumper will not be a smooth overall as a Edelbrock carb with its demand sensing secondary air door.
If you going to switch carbs, get a 750cfm carb.
The Edelbrock 750 carbs work nice too (1407)
But you need to upgrade everthing else first before worying about another 100 or so carb cfm.
Much more to be gained from exhaust, intake and cylinder head mods.
What intake manifold do you have? what cylinder heads?
A double pumper will not be a smooth overall as a Edelbrock carb with its demand sensing secondary air door.
If you going to switch carbs, get a 750cfm carb.
The Edelbrock 750 carbs work nice too (1407)
But you need to upgrade everthing else first before worying about another 100 or so carb cfm.
Much more to be gained from exhaust, intake and cylinder head mods.
What intake manifold do you have? what cylinder heads?
11-02-2003, 08:21 PM
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Car: 1988 trans am
Engine: 5.7 gm H.O. crate engine
Transmission: 700r4
Originally posted by LilJayV10
what throttle bracket did you use? I have the DP bracket from holley. I am having a hard time setting the throttle pressure and dana at probuilt says I don't have the correct geometry. I was just wondering what you had, Thanks.
Jason
what throttle bracket did you use? I have the DP bracket from holley. I am having a hard time setting the throttle pressure and dana at probuilt says I don't have the correct geometry. I was just wondering what you had, Thanks.
Jason
EDIT: you need this - http://store.summitracing.com/partde...=HLY%2D20%2D95[/url]
11-03-2003, 04:24 PM
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Car: '82 Z28
Engine: 350HO
Transmission: M4
Originally posted by F-BIRD'88
Keep the carb you have. You're not going to see much gain from going to a 650 from a 600.
A double pumper will not be a smooth overall as a Edelbrock carb with its demand sensing secondary air door.
If you going to switch carbs, get a 750cfm carb.
The Edelbrock 750 carbs work nice too (1407)
But you need to upgrade everthing else first before worying about another 100 or so carb cfm.
Much more to be gained from exhaust, intake and cylinder head mods.
What intake manifold do you have? what cylinder heads?
Keep the carb you have. You're not going to see much gain from going to a 650 from a 600.
A double pumper will not be a smooth overall as a Edelbrock carb with its demand sensing secondary air door.
If you going to switch carbs, get a 750cfm carb.
The Edelbrock 750 carbs work nice too (1407)
But you need to upgrade everthing else first before worying about another 100 or so carb cfm.
Much more to be gained from exhaust, intake and cylinder head mods.
What intake manifold do you have? what cylinder heads?
so stock Votec heads, Edelbrock RPM Air-Gap, headers, high flow cat.
I had a 1407 on the motor, but it seemed way to big, the motor would bog like crazy at low rpm, i didn't feel like messing with the metering rods or any of that. i swaped that out for a 1405, and i runs much better now.
but i keep thinking that a 650DP would be much better suited for the motor.
11-18-2003, 08:50 PM
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Car: 91 RS
Engine: Carb 350
Transmission: 700R4
Q-jet or holley or demon?
so we jus got done puttin a mildly built 350 in my car...over the winter..i wanna build up the motor a lil more tho and put a new set of vortech heads and a new manifold on..what would be suggestions on the better carb for it? my neighbor is stuck on the qjet bein real nice...but i want other opinions too
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