McGee68

Hi all, looking for help on a low compression 350. I have a rebuilt 350 in the 69 F85 i am finishing up. I am at this point assuming it is around 8:1 with big dish pistons and 7a heads and stock profile cam. The engine has a edelbrock performer and holley 600 on it now and I added headers. It is backed by a TH400 and I think 2.93 rear gear. The body work is about complete and I am trying to keep this car a driver. Of course it's a total dog for performance at this time and I am planning on a 455 build down the line but just not in the bank right now. I am looking for a cam that will build more torque and other suggestions like timing settings to help wake it up for now. I am thinking a rear gear change may be in order first but with a 455 coming I'm not wanting to go to crazy with gear.
-Nick

oldcutlass

What distributor is installed? A gear change is the most bang for your buck for a butt dyno improvement.

McGee68

HEI already

oldcutlass

What is your timing? Should be around 16/18* btdc at idle, with a total of 34/36.

McGee68

Car is still in the body shop but I will check my timing

McGee68

Thoughts on gear ratio with a pending 455 swap later?

Kennybill

Being a cheap ***, I've had good luck re-purposing used factory 455 cams in lo-compression 350. You get a little more lift and the factory cams torque output till 3000 rpms is seldom beat with an aftermarket cam. If you are making a driver, 3:08 to 3:42 gears are good for the street. If you are wanting a National Record Holder then start at 3:73 to 5:13 depending on whether you're going for the 1/8 or 1/4 mile.

olds 307 and 403

A 3.08 or 3.23 gear is a good step up, depends on how much highway driving you do. The smog 455 cam is similar to some of the manual 350 cams and the 307 HO cam. You probably need a new timing set anyways. If it has the most common HEI curve, set your base at 20-22 degrees.