lildemars09

iTrader: (2)

Does anyone know the measurement of the LT4 intake, the holes that sit on top of the heads? I am just curious to know because I am trying to port my intake myself and just wanted some measurements of the LT4 so i can use that as a reference and hopefully try and match it.

Thanks guys

DisasterFormula

iTrader: (1)

Unless you have a cam and/or heads, you don't need to port your intake and don't need a 58mm TBI. Also, you don't want your intake openings to be wider than the ports on the heads b/c what happens is the incoming air hits the "lip" that forms from the difference and messes up the incoming air flow, reducing power.

96capricemgr

iTrader: (1)

I know someone who once tried porting an intake to measurements. In the end his ports were the same size as his head porter had done them in the heads but were at the wrong height. Had to buy another intake and start over.

The LT4 intake manifold was the same as the later small port LT1 intakes.
The heads I do not think a novice should go opening up that dramatically.

Do a search for "gasket matching" sounds like that is the mistake you are trying to make.

lildemars09

iTrader: (2)

yea I am not going to attempt it then