im dropping a renesis in a 1st gen. only the core itself will be stock. everything else will be after market. it will be a daily driver. but still want all the power i can get. not just at 9k...

so, i have a set of gsxr 600 ITB's that im going to be using. i have an idea of what diameter, length, and over all design of the runners im going to use. but i would like to get some insight before i go ahead and start making these...

also, i was thinking of mounting the velocity stacks into a plenum and running a pipe as you would a regular intake pipe.

some good info from experienced manifold builders and fabricators would be good...

thanks...

 

i dont know about the renny motor but on a t2 block i believe that 8 inch runners were found to be optimal. as far as i know there has only been 1 guy on here to do hayabusa itbs and it was trial and error. u are gonna have to find that stuff out on your own as u are the one and only i think ever doing this to a renny

 

8" runners are WAY too short! Double it. Too many people are caught up on shorter runners. Don't do that. Start long and shorted them if your powerband doesn't go up as high as you want.

 

my original plan was 14 inch runners. then just to shorten them if the power wasnt where i wanted it to be. i think 8 inch would leave me with no low end.

what do you think about the plenum around the veloicty stacks? even worth it? the radiaitor might be pushing hot air right into the runners...makes sence in my head.

 

The plenum around velocity stacks isnt a bad idea. BMW, Ferrari, etc all so the same thing. They also use AFM's, but it would allow a way for you to "channel" cold air to the velocity stacks. Just make sure that you make the plenum, and pipe to it, large enough to not be a restriction.

- Chris

 

Whether the plenum is before or after the throttleplates, it will still affect tuning. I encourage you to try it. Learning is half the fun. Try larger ones and smaller ones. You may be surprised at the results.

 

the plenum idea was to be a 4 inch tube, 2 inches wider on each side than the itb's. with a 3 inch inlet leading down where in front of the radiaitor area with a filter.

 

kinda like this...but not so colorful

the square represents the motor. and the shape around it is my attemp at replicating the shape fo the engine bay...


dark blue: runners and ITB's
light blue: velocity stacks
red : plenum and intake