I was wondering if siamese porting the runners or the lower intake was the better thing to do. I have the edelbrock intake and runners so I could siamese either one of them. currently i am running.
355
vette heads
zz9 cam
9.5:1 comp
intake/runners
24lb injectors
I also have a paxton charger not on car at the moment

anyone have any ideas on which one i should siamese and how far i should go.

 

I dont recommend siamesing the Intake, I gave it a shot basically because I wanted the RPM's more than the torque but in the end its just a slower ET, the trade off isn't a fair one.

 

i ported the stock base for my engine. and i still gained torque at the bottom. i'm up to 362.9rwtq @ 2700 right now.

 

ported or siamesed?

 

well siamesed to be exact. here's a pic. now all i need to do is get rid of the stock runners. get some SLP and completely siamese them.

 

thanks for the info. I think I will try siamesing the stock lower that i have in the closet to see if it helps me on the upper rpms.

 

when you do the siamesing, you may cut through the bottom portion in some areas like i did. you will need to have them welded shut. i ended up cutting through 5 areas where the ports go along the bottom. when you look at the intake from the bottom, you'll see thin areas where the ports run along the bottom.

 

how much more rpm would your motor turn after porting your intake?

 

you can see by the dyno that it started picking up at the 3500 mark. but, because of the stock runners still on it, it still peaked at 4400 rpm. also the l98 heads i ported. so my next step to increase rpms is to get some SLP or AS&M runners and completely siamese them.