Building and Setting Up a Q-Jet for a 283 Making about 300-325HP

[grodriguez1987]

Hello, I am new to the forum I currently building a 283 and planning to use a Q-Jet.  Here are my specs:

283 Bored .030"
Quench Set at .040"-.045"
96'-99' 305 Vortec Heads cut down to 55-56cc to achieve 9.5:1 static comp
Edelbrock Vortec performer manifold
Standard GM HEI
Comp XE256H Cam (DCR 8.44:1, 212/218 @ .050", .447/.454 valve lift, 110 LSA)
Corvette Ram Horn Exhaust manifold with true dual system
Expected peak power @5400 rpm is 320HP

The book provides as baseline setup for a mild engine making up to 350HP.  Considering I am using a small displacement engine, with power fairly short of 350, what should I adjust to make up for the difference if any at all?

[novadude]

Shouldn't need to do much at all to the carb for that engine, IMO.  I don't know what carb you plan to use, but a stock 67-69 327/350 ci carb calibration should be pretty close to perfect.  If using a late model carb, Cliff's recipie #1 would be a good starting point, but I think you could get away with even less idle fuel.  JMO.

Nice small displacement SBC combo!

[Cliff Ruggles]

What is the carburetor part number on the unit you plan on using?  Q-jets are application specific and some have a lot more idle fuel and idle bypass than others depending on when they were made and what they were used on.

With Vortec heads and no exhaust crossovers you are going to need a model that will convert to electric choke.

Nice engine build aside from the camshaft.  I am NOT a fan of those cams.  Not enough seat timing and LSA too tight.  They also have a bad habit of munching lobes so make sure that you use USA made lifters on it.  Comp has a bad habit of supplying springs with WAY too much pressure to keep those fast ramp lobes in check, which only grinds things up faster and sooner than they should.....