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'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.

 

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

 

750DP Demon on an LG4?!

I hope you are slowly buying parts for a new engine... or it fell off a truck or something.

 

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.

 

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?

 

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.

 

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

 

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

 

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?

 

i work at a sheet metal fabrication shop so i made one out of 14 gauge stainless. i didnt evenb have the geometry in mind when i made it but it works.

EDIT: you need this - http://store.summitracing.com/partde...=HLY%2D20%2D95[/url]

 

thats what I have, but its not working

 

Its a 350HO(330hp, 380lbs tq)...

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.

 

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