Hi Guys

I have a back-up intake manifold. I just had it sand blasted. I was thinking.....the walls between the two intake holes ....would it be a good thing or bad to cut them out all the way through to the other side thus making one big tunnel for a total of 4 intakes as apposed to 8? Or should I just try and enlarge the diameter of each hole without touching the walls?

Suggestions please! I also have a back-up phlenum and runners to work on. Suggestions for those would be appreciated as well.

Thanks

 

I believe you have coolant running through there... not entirely sure, but I know for carb manifolds coolant passages are everywhere making tunneling/enlarging a tricky idea...

On the other hand it may work, but you might end up with the single plane effect where torque on the low end is sacrificed for high end torque.

 

I'll bring the manifold to dyno day. The walls are very thin and run parralell to each other perfectly straight on an angle.

 

Do a search in the TPI forum for siamesing runners and the manifold. I believe this is what you would want to do. I considered doing it myself but opted just to wait and buy the bigger runners when the time comes.

 

Hey that intake looks familiar!! ..BTW are you gonna use the shield underneath it..I could use it since I forgot to transfer it over when I did the swap..

Daz

 

You know.....it should look familiar The shield underneath is spic and span too! Why didn't you transfer it over and what's it for? Does it cause a problem if you don't have it? Ya sure. I have one in the car already so I'm okay. Just hand over $50 and it's yours



j/k remind me for track day

 

I hear siamesing the intake ports about 4" in shifts your torque up in the higher RPM range.

 

Nath...I did a search on siamesing and wow! Alot of info. More than I could understand. Guys were buying 500-600 big mouth maniflods and SLP runners and porting them! They said that even 3inch's is enough. As for gains it wasn't etched in stone. One guy with certain mods lost no low end torque and gained high end all the way to 5800 rpms. Also gain hp. What I wasn't sure of is that if I port the runner side what do I do with the head side?

 

don't siamese the head side, you may get into sealing problems.. what you want to do is taper out to the head side and port match the head side, and smoothen out the casting a bit.