Which Carb?

[LINKMS15]

I am having a stroked small block built and don't want to try and reinvent the wheel with choosing the correct carb for offroad abuse (race not play). I have heard so many people saying that they either love or hate their carb. I would like to hear from those who love their carb and which one. I have a Demon for it as of right now but am willing to change depending on response. EFI is not an option at this point.

Thank you in advance,
Brandy Chrisman

[billymanfroy]

I run a Holley HP on a 500+ hp engine. It's a 650, but my engine builed told me just the difference in quality of the casting (no choke housing) and other stuff on it is good for 15-20 hp over the box-stock 650 cfm holley he used to dyno it with. I have done NOT ONE THING to the carb to make it off-roadable, because it's never had much of a problem. We just had a guy go through it and set it up to the factory specs, and it is absolutely amazing to me how well it works now. He did change the primary power valve to a bigger one and fiddled with the pump shot some. No bobbles, and it just smokes 'em instantly when you crack the throttle. I like it, but we do have a Holley Commander 950 FI setup that's going on soon.

The cheapest I found the HP's is at Summit.

[partybarge_pilot]

About the only other recomendation would be the "off-road" needle assmbly.

[Go Go Gadget Arms]

I'd keep the demon. call barry grant for any tuning or driveability issues. but theyre hands down the best carb in my book

I have a 750cfm holley 4150 mech secondaries (double pumper) its pretty close to the same thing as a demon but takes more time to adjust it

[LINKMS15]

My engine builder was recomending the holley HP series, but I have had bad experiences with holley's power valves. I don't know if they have worked that out (it has been a while since I delt with carbs) I also don't want it to burp and flood during heavy whoops or rough sections. Does the "off road" needle assy. help with the hesitations or are there any other options or mod's available?

Brandy

[scottm]

I have been collecting engine and carb books and holley carbs for a year trying to decide this same question. The literature is pretty much in agreement that vaccuum secondaries and annular boosters are the way to go for crisp throttle response and good low rpm torque, especially with an air-gap manifold like the Victor Jr I am running. Holley has an 850 with annular boosters, but thats too big for my 383. So I just ordered a Demon 750 vacuum race carb with annular boosters, series 540-something, and with optional spring-loaded float needles for off road. Several knowledgable engine builders have told me Holleys are good but Demon is better.

OK heres a couple links. I am getting a mighty Demon 5402020V. The second 2 indicates annular boosters.
http://www.barrygrant.com/news/articles/products/product_002.aspx
http://www.barrygrant.com/news/articles/products/product_013.aspx

[LINKMS15]

I have been collecting engine and carb books and holley carbs for a year trying to decide this same question. The literature is pretty much in agreement that vaccuum secondaries and annular boosters are the way to go for crisp throttle response and good low rpm torque, especially with an air-gap manifold like the Victor Jr I am running. Holley has an 850 with annular boosters, but thats too big for my 383. So I just ordered a Demon 750 vacuum race carb with annular boosters, series 540-something, and with optional spring-loaded float needles for off road. Several knowledgable engine builders have told me Holleys are good but Demon is better.

OK heres a couple links. I am getting a mighty Demon 5402020V. The second 2 indicates annular boosters.
http://www.barrygrant.com/news/articles/products/product_002.aspx
http://www.barrygrant.com/news/articles/products/product_013.aspx

My engine guy was saying the same thing about the intakes, he said to run the "Dart Kool Can" intake, they don't make them anymore, but I found one back in the mid west. It is almost exactly like the "air gap" but seemed to flow a little better, He even said if I couldn't find one use the "air gap". It looks like we are on the right track! Thank you for your imput.

Brandy

[scottm]

Well air gap refers to any manifold where the runners are sparated from the base of the manifold, so the intake charge stays cooler. There are many brands and types of air gap manifolds, like the edelbrock victor jr, the performer airgap,etc. Carbs with annular boosters work better on air gap manifolds because they release the fuel into finer drops, which helps it atomize better in the cool manifold.