Hey everyone,
The motors running good (300 miles on it!). It had bad hesitation but I fixed that by upping the fuel pressure, now it runs great, plenty of power

However, I am having trouble getting the idle right. I upped the jets in my Holley 600 from 65's to 70's (a big jump, I know). Now I can't get a good idle, and when I put it in gear it drops about 400RPM and wants to stall (but doesn't). Are these jets too large? There are no secondary jets, it has a metering plate.

Thanks!

Main jets don't affect idle unless the throttle blades are open too far for some reason (like clogged idle circuits).

Check to be sure no gasket material or something of that order is plugging your idle circuits.

Man! With all the stuff you've got on there, I'd be looking for a 650cfm right out of the box. Some things you didn't mention, what tranny? What intake(spreadbore or square hole). Compression ratio. I hope you have headers on there! If you don't your losing about 30-40 hp. I would trash the 600 (or sell it to cover some of the cost of a 650) It's kind of a universal carb for many applications. I had one on a 455 poncho I jetted and it gave gobs of torque and power to about 3500rpm 2.02 60 ft. with a 4000 # Lemans I think with your 3.73s the 650 would breathe better.

Wow, it's been a little while since I've posted this .
Since then, I have replaced the distributor w/ a Mallory and tuned the ignition curve, which helped alot. I still have the 600, but I think I am going to get a 700 double pumper. Oh, and the 600 had a blown power valve (probably from the backfire when I was first trying to start the motor). So, needless to say it runs alot better, and it has alot of power, but it is week from 2000 to 3500 RPM. Full timing comes in at 3000 and is about 30* (12* base). My fuel pressure changes alot, I am still using the Mallory 3-port regulator, so I think I will replace the in-tank pump w/ a peice of hose and put an external pump on to keep my fuel pressure constant.
The intake is an Edelbrock Performer made for the Vortec Heads, it's dual plane and will accepct spread or squarebore carbs. Compression is 9.6:1, I have crappy Edelbrock headers from my 305, so I am going to one day replace them with Hookers. I have the stock auto-tranny also, but that's coming out when I get the money for a 6-speed. Also roller rockers are in the future.
-Thanks for the reply!

That timing is still a bit weak if you only have 30* total.
Smallblocks usually like between 34 and 36* total. Since you have 3.73 gears & probably a 700R-4 it would probably like it all in by 2500 RPM.

Are you driving on the street? 700cfm sounds a little large. Could loose bottom end power some. 650 would give you better perf. across the board. One of the biggest mistakes is too large of an application on the street ie: loss of perf. and crapy fuel milage. But, if you were worried about milage, you wouldn't have 3.73's huh?