Which intake for my truck???

[Olive1970]

Originally Posted by INSIDIOUS '86

First off ditch the Holley spreadbore the whole lot of those should have never been made. Those things are a nightmare

Second. What's your cams duration?
A performer rpm intake seems like the better match so far
Posted via Mobile Device

Are the Holley Spreadbores really that bad? It seems like it runs the best on the truck so far, well for the most part. I also have a Street Avenger 670.

The duration at .050" is 234 244 on the cam.

[INSIDIOUS '86]

Originally Posted by Olive1970

Are the Holley Spreadbores really that bad? It seems like it runs the best on the truck so far, well for the most part. I also have a Street Avenger 670.

The duration at .050" is 234 244 on the cam.

That's a fairly healthy cam. Your intake valves are a little small for that the air gap is a good choice or the wieand equivalent which I a little cheaper and has some more low end and very close to the same top end. What's the compression? Some 2.02 fuelie heads will bring some more out on that engine.
As for the spreadbore they work but they were designed as a quadrant replacement and the over size secondary's make for an unstable fuel curve at the top end. Depending on what rpm your turning that engine normally a normal double pumper or vac secondary will give it a good all around feel. The plus side is the spread bore will give a better cylinder fill and response at low rpm

Right now I would lean towards the wieand
Posted via Mobile Device

[Olive1970]

Originally Posted by INSIDIOUS '86

That's a fairly healthy cam. Your intake valves are a little small for that the air gap is a good choice or the wieand equivalent which I a little cheaper and has some more low end and very close to the same top end. What's the compression? Some 2.02 fuelie heads will bring some more out on that engine.
As for the spreadbore they work but they were designed as a quadrant replacement and the over size secondary's make for an unstable fuel curve at the top end. Depending on what rpm your turning that engine normally a normal double pumper or vac secondary will give it a good all around feel. The plus side is the spread bore will give a better cylinder fill and response at low rpm

Right now I would lean towards the wieand
Posted via Mobile Device

I am not 100% sure on what the compression value is. I have known for awhile that the heads are the shortcoming on this engine, I was going off of what the engine builder suggested but those suggestions have not always worked out. I wish that I could get new heads but it is simply not in the budget for me.

I have an old weiand on there now, but it is leaking (sucking air) so that is part of the reason for replacing it. As far as rpms, I am turning up to 6k with the hammer down. My biggest issue has been a stumble or hesitation when accelerating from a roll, I didnt have it as much with the spreadbore carb as with the street avenger. Granted, I found out the intake was leaking when I pulled the spreadbore off so that has made matters worse. Just not sure which carb I should use either?