I know I can look up the detail specs and I will later, but can one of you OLDS guys give me a brief explanation on the differences between the 325 and 350 hp 69 400's. (carb, dist, timing, comp, etc.)

This is my first OLDS restoration and I am just beginning. The car is a complete rebuild. It has the Orig 400 that has never been apart. It sat up for a long time (covered, with carb and hood) so I hope the block is OK.

Thanks

 

My first thought would be different cam, and bigger valves in the heads for the higher HP motor.

i only have a 72 book, so I cannot help you with specs.

John

 

Without looking at the books more HP was gotten out of the same size engines by different camshafts, bigger carbs/jetting, adding dual exhaust, and sometimes a boost in compression ratio.

 

OK, thanks. 25hp is not much of a difference, so I thought it probably was in the area of Dist curve, timing advance, or carb. The engine has the C heads so the valves are probably the same and I think the compression is too. I am going to rebuild the engine to stock specs, and I'll check the specs to if I can get that extra 25hp.

 

C heads came with two different valve configurations. For example, Toronados were all big valve heads, Delta 88's were not from the factory unless it was able to be ordered or the motor changed later.

You can bump HP and Torque in your stock looking motor buy shelling out just a little more money in a better cam.

John

 

I didn't see an answer to the original question, but the differences between the 325 HP automatic 400 and the 350 HP manual trans 400 in 68 and 69 were mainly the cam profile and distributor. The AT motors received a less agressive cam. Of course, there was the W-32 that basically used the 350 HP MT motor with the beefed TH400.