Speed Demon Carb
Thread Starter
Drifting
Joined: Jan 2002
Posts: 1,484
Likes: 0
From: Northampton Ma
Speed Demon Carb
I'm installing a new cam in my '77 and it has snowballed just like very other project. Since the intake and carb will be off I figure I will replace both of them. I would like to go with a Speed Demon 750 cfm electric choke carb, Edelbrock Performer RPM manifold, Comp Cams 268H with all the lifters, springs, etc, and Roller Rockers with new pushrods. I will be using stock heads.
I have several questions:
1. does anyone know how well this package will work?
2. Will the speed demon 750 and performer RPM fit under the stock hood?
3. should I go with 1.52 or 1.6 roller rocker w/pushrods?
Any suggestions, install/removal tips, or anyhting else would be appreciated.
I have several questions:
1. does anyone know how well this package will work?
2. Will the speed demon 750 and performer RPM fit under the stock hood?
3. should I go with 1.52 or 1.6 roller rocker w/pushrods?
Any suggestions, install/removal tips, or anyhting else would be appreciated.
Burning Brakes
Joined: May 2000
Posts: 765
Likes: 0
From: Canton GA
Re: Speed Demon Carb (Ryan77)
Can't tell you...exactly on the performance. But I haven't heard any complaints about Demons. The only possible thing is that maybe a 750 is a little too big....go to the demon carb site...and send them your specs and see what they recommend...along with what you want to do (Street, drag occasinally, etc). I did this after I had already ordered the Road Demon, and then got to send it back for a Speed Demon 650.
I can help a tad on clearance, although I'm not sure how a 77 compares to a 72 (if anything....you may have a little more). I'm using a 1.5" drop base open air cleaner with 2.25" x 14" K&N on top of the Summit Crosswind (which is identical in height to the RPM Airgap) and with the 650 SD it closes. Make sure to use the Putty Test trick for clearance. You can find an article on it, on corvettefaq.com...basically just use silly putty or plumers putty on top of your air cleaner....close the hood, lift back up, and the height of the putty is how much clearance you have to play with.
I can help a tad on clearance, although I'm not sure how a 77 compares to a 72 (if anything....you may have a little more). I'm using a 1.5" drop base open air cleaner with 2.25" x 14" K&N on top of the Summit Crosswind (which is identical in height to the RPM Airgap) and with the 650 SD it closes. Make sure to use the Putty Test trick for clearance. You can find an article on it, on corvettefaq.com...basically just use silly putty or plumers putty on top of your air cleaner....close the hood, lift back up, and the height of the putty is how much clearance you have to play with.
Racer
Joined: Feb 2001
Posts: 315
Likes: 0
From: Pensacola Florida
Re: Speed Demon Carb (Ryan77)
I agree with Zora_Rules. I think 750 will be too big for your '77. I plan on going with Demon as well for my '77, but the 650 will be plenty big.
Remember BIGGER is NOT always BETTER!!!!!!!!!
Larry :seeya
Remember BIGGER is NOT always BETTER!!!!!!!!!
Larry :seeya
Instructor
Joined: Jul 2001
Posts: 240
Likes: 0
From: kennett square,pa,us
Re: Speed Demon Carb (Ryan77)
Ryan 77,
I use a Speed demon 650 w/ mech. sec.(4spd) and it works GREAT. I am running a Comp. 274 XE cam which has a little more duration also.
The carb 7 intake should fit under the hood of the 77.
I use 1.6 rocker on my cam, but would like to try a combination of 1.5 & 1.6 sometime. They are a little expensive to experiment with though.
With the stock heads, don't expect a noticable difference with the roll rockers.
I use a Speed demon 650 w/ mech. sec.(4spd) and it works GREAT. I am running a Comp. 274 XE cam which has a little more duration also.
The carb 7 intake should fit under the hood of the 77.
I use 1.6 rocker on my cam, but would like to try a combination of 1.5 & 1.6 sometime. They are a little expensive to experiment with though.
With the stock heads, don't expect a noticable difference with the roll rockers.
