Hi, I have a 1964 chevy Nova. I just bought a 250 engine that has been honed out and cleaned up. Also it has the lowest powered high performance cam in it.

My question is would it be able to run good with a holley 600 cfm carb. and headers? -or would this carb be to big for the engine?
Thanks

It'll work with the Holley 600 assuming the carb is in good shape. However, you're better off going with something smaller like the Holley 390 or Edelbrock 500 carb. Do a search on 'holley 600' or something similar and you should find plenty.

Sure!

But like Brad says, a 390 or 500 would be better for a stock 250 with a 'mild' cam etc.

Adding the 292 "C-40" manifold or some headers with it, would be good too..

Good luck.

I am in agreement with Brad and John, also stay away from the mech secondary Holley 390, most of those thing's are set up to feed V-things at 10,OOO+ rpm., so stick with one's that have vaccum secondary.
Dan

I have a question regarding this. I've got a '70 C-10, 250, header, 3 speed. The engine was rebuilt eight or nine years ago with a PAW kit and their "performance" cam. I have long since forgotten the specs. Anyways, I had been using the Monojet on it until I parked it a few years ago, but the carb had always been a problem. I was recently able to talk my wife into allowing me to resurrect my yruck, and I have been plagued with carb trouble. The original had vacuum leaks past the throttle shaft, and the screw holes for the throttle body were stripped. I swapped the original carb for a Tomco rebuild. It bled over and flooded out at every opportunity, so I replaced it with another Tomco (under warranty). I have had problems from the start with that one, but the warranty ran out before I did anything about it, so I rebuilt it. I still can't make the thing idle, and it stumbles badly just off idle.

It seems to me that I am barking up the wrong tree with this approach. I am considering replacing the carb with either a 2 or 4 barrel Holley, but the only source I have seen for an intake for either is Clifford. I swear I remember Offy making a manifold for it, but I can't find one. Any advice?

Also JC Whitney sell the Offy 4 bbl manifold

you can search on EBay. Always had something related there.

Good luck

A 600 is too big IMO. I have a 500 CFM 1404 Edelbrock on it and I have it leaned out just about as far as possible, and it could go a bit more but I'd need to have metering rods make for me. I looked for a cheap 390 to try out, but all the cheap ones were junk. I am going to try the Q-Jet out this summer.

I believe PAW performance has the intakes too. You can find their contact info on the net.

Thanks. I did some looking today and found that the Road Demon Jr 525 runs around the same price as the holley 390 and looks like a nicer package. I want to do a little more research and try to figure out how flexible the Demon is before I commit either way. I also looked at the Holley 2300, 350 cfm, but I think that the big 2bbl will probably suck gas a lot worse than a vacuum secondary 4bbl. I absolutely forgot about Good ol' JC Whitney. I'll check them and PAW. I already did a bit of looking on E-Bay, and didn't find anything promising.

Hello Cardinal X,
I REALLY don't like that 525!!, they are set up way to rich, most of the parts do not interchange with the Holleys, it easily weighs twice as much as a Holley, and (brand new) the o-rings on both of my float valve's leaked!!

I can't speak for the King Demon or the Street Demon, but my Demon Jr was never right, I can make a Holley 600 run better (on a 250) than that 525 Demon Jr.

The 390 Holley or the Edelbrock 500 are a better choice.

Dan

I have the 525 cfm Road Demon (not the Junior) on my 261. No Problems at all. Maybe a hair to big. I will try a Q-jet soon.

[img]http://www.oith.de/forum/phpBB2/garage.php?mode=view_gallery_item&type=garage_mod&image_id=75[/img]

C-Dan-D-Luxe,
That is a nice looking carb!

With a Q-Jet, make sure you or someone you know, does know how to tune it.
I would say, do not expect it to work good just by bolting a stock one on. Two cents::

MBHD

Langdon's has the Offy manifold for $225. I'm leaning toward the Holley 390, as most of experience has been with Holleys. Between the new carb and the electronic ignition I'm installing, it should run OK. Thanks for the help.