Hello all, I'm rebuilding my 350, trying to get the most HP with out breaking the bank, any suggestions?

 

Completely understand not wanting to break the bank...what year/model is it going in, what transmission, what rear axle ratio? Will it be driven often on the highway?
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Unless it needs a rebuild, you may get more for your money through a transmission replacement or axle ratio change.

Good luck!!!

 

Its 1968 convertible all stock

 

​​​​​​68 vert, very nice.
Two speed or three speed auto? What are the letters in the bottom of the speedo PRN___? Does it shift once or twice? If it is a two speed auto a lot can be gained with a different transmission. This is all if the 350 doesn't need a rebuild, if it needs it then it needs it.

Good luck!!!

 

Do it in steps:
What are your performance expectations?

Step 1. After teardown & inspection, do a stock rebuild with a mild cam, degreed properly, Intake port matched to the heads, head port clean up with a good 3 angle valve job. Refresh the QuadraJet, distributor and fuel pump. Use a machine shop familiar with Oldsmobiles!!!!

Step 2. TH350 trans? If its the stock ST300 Junk Away consider an upgrade to a TH350 or a properly built 4 speed TH2004R. Rebuild the trans with a TransGo shift improver kit and an adjustable modulator. TCI clear synthetic trans fluid.

Step 3. Consider a 308 or lower rear gear. It likely has the 2 series gears. This is where you will see all the modifications come together.

Keep in mind the cooling, fuel and exhaust systems will need upgrading/rebuilding/replacement as well to handle the new mods. Don't forget you need a solid chassis and braking systems as well. Let the MAWs commence!

 

There were two versions of the 350 engine available in that car, a 10.25:1 4bbl and a 9.0:1 2bbl.

As already asked, does the engine really need a rebuild or is a rebuild something you want to do just because?
Adding a third (or fourth) gear to a vehicle with a 2 speed transmission is a huge performance gain, as is changing the rear gears from the typical 2.56 to something in the 3.xx range.
My first car was a 1970 Supreme 350-4bbl (same engine as 1968) and swapping the 2.56 rear for a 3.08, then later a 3.55, made a world of difference in performance. A cam upgrade, headers, and a bit higher stall torque converter made it a really fun car to drive on a daily basis (school and work).

 

As far as l know the trans is a TH350, and also l have a warped head, l was thinking of getting some aluminum heads.....

 

Be aware the aluminum heads are made for big blocks and therefore have larger combustion chambers and intake runners. It will take some modifications to use them on a small block. Do more research before you spend money.