89-S-dime

iTrader: (3)

I am looking for some input (fast355, thomas1976, ect.) on possibly boring out a Edelbrock 3704 to 46mm and matching it with a 46mm TBI base.(have upgraded the fuel pressure regulator)
My expected RWHP for my build is around 250-260 hp. I have already ported and gasket matched the 3704 when I did the heads. dont know if it would be over kill with a such mild build.

Fast355

iTrader: (2)

46mm should not be a problem but that intake will likely fall short of that goal. It is very similar to the GMPP TBI Vortec intake and the most I have seen out of that intake is 250 RWHP and that was running a LT4 Hotcam. Years ago I put a 3704 intake on my G20 van when I put a GM crate engine in it. The stock TBI intake was badly corroded around the water passageways and thermostat housing. The 3704 ran really clean on the emissions dyno, did well on fuel, perfect driveability but anywhere over 2,000 rpm the Performer RPM intake I elongated the 4 center bolts of and swapped in its place blew it out of the water!

89-S-dime

iTrader: (3)

thanks for the reply, i looked into different manifolds but i have to keep the egr at the intake manifold, so I am stuck with a stock or the 3704. plus I got the Edelbrock cheap.

thomas1976

My DIY reworked 3704 works well on my DIY combo that is certainly making over 300RWHP. https://www.thirdgen.org/forums/tbi/...ml#post5629515

I would not cut corners and bore it at least .020 bigger than the TB bores and give it an overall treatment like I did, with focus on the eqalizing port sizes/shapes, removing the lower radius ramps and chamfering/smoothing the edges in the bottom of the bores particularly the deep one.

89-S-dime

iTrader: (3)

Thanks Thomas1976 been following your thread for a while now, great info