350 build up

[Wamp]

Now that the interior is all done I can start working under the hood on the STOCK 1974 L48 350. What was Chevy thinking even building this snail engine. Want to build up the stock engine, (money is not a problem). Give me your expetise, where do I start?

 

[KenSny]

GM was thinking - Oh my gosh, we got to get our cars to meet the emissions police specs or we're in big trouble..... Solution was to detune-detune-detune until very little was left of a 350's potential.

First thing to do is to let it breathe. Install a true dual 2-1/2" exhaust system. Yes, I know, '74s had a dual system, but it's probably only 2" and the muffler's are restrictive. Don't forget to retune the carb otherwise you will be way lean. This will give you a big seat of the pants change.

Go for the heads & cam next. While you are there, swap out the timing chain for a true roller.

Maybe think of installing a more tunable carb. Lots of people like the Qjet, I don't, so I'm biased. Go to an aluminum intake manifold and a square-bore Holley.

 

[69vettester]

Wamp,
capacitive discharge multi=sparking ignition systems, have a twofold effect on a "old technology", factory, dogged motor.

It will increase the efficiency of the motor especially during acceleration, by providing multiple hot long duration sparks for thorough combustion. after 3k+ rpms, there isnt time for multisparks , it just provides the long hot spark.

The other result is increased power.

Its necessary to use 8.5mm performance wires or equivalent, with these systems too.

So, if your motor is fairly fresh, with a correctly setup carburator ,its possible you could get increased power and increased MPG to boot.

Good luck with your upgrade combos, I think youll start seeing real results soon after you start upgrading. I sure did with my 330hp Small Block.
TC