Ryan Wandell

I have an 89' RS with the LO3 5.0 and it has a carb swap done on it.. The carb is a 600 CFM Edlebrock 4 barrel, and I'm wondering if this is TOO much for a 305? People have actually told me to swap it for a 750, but I think the 600 on it now is too much as it is.. When you're driving at like 25 and stomp it to WOT it bogs down for like 1-2 seconds before it takes off.. and from the first start of the day, it'll burn a bluish smoke for about 3 seconds and then stop.. like it's got too much fuel on start up.

Does it need jetted down, or what's going on? Is it just not tuned properly?

ImBrandon

Sounds like you're burning oil. Your plugs are probably fouled too. I'd pull a plug or two. Sounds unhealthy.

JaBoT

No it's not to much. Although the people who told you to put a 750 on it you might not want to listen to lol.
The bog is probably either a timing issue or a miss adjusted pump shot.
Try moving the pump shot arm into one of the other holes and see if it gets better.

Check you timing at idle too.

As far as the blue smoke on start up. Welcome to the world of small block chevy valve seals. Double check the plugs. If they don't show signs of burning oil. it's just happening when the motor sits and i wouldn't worry about it.

Ryan Wandell

The cars got 67K original miles.. it's sat for a while as you can probably imagine. It does have an accel distributor/wires and stuff.. so I figured when I bought it they had to be semi new atleast. I'll replace the plugs, do an oil change (I've had this car 3 weeks dont hate haha), and put a timing gun on the wires and see if i got a bad one or something.

It probably just needs a tune up.. Atleast I hope.

ImBrandon

After your tune it up you should beat the hell out of it that'll wake it up.

Cosmik Debris

As another poster said the smoke is probably the valve seals. When the carb was swapped did the distributer get replaced with a mech/vac advance model?

InfernalVortex

iTrader: (4)

Blue smoke on startup is valve seals. Blue smoke upon acceleration is bad piston rings allowing blowby. A lot of it. Alternatively it MAY be massive overfueling.

If you can, stomp it and make it smoke and then quickly u-turn around and see if you can smell it. Oil smoke has a very strong, lingering smell so if you can get back around to it in a reasoanble time you may be able to identify it. Or just have a friend do it and you smell it yourself.

A bog is something else entirely, needs some carb tuning. 600 cfm is probably perfect for you.