Thread: Ported throttle bodies
03-11-2007, 09:28 PM #1
Ported throttle bodies
I have been experimenting with throttle bodies as many of you know and made some substantial progress over the stock arrangement, or any other arrangement out there for that matter.
Jims1300 previously used no flame arrestor at all, only the factory gutted airbox, which makes more power than any other combo that i am aware of.
I machine the throat of the throttle bodies with a special 60 degree cutter only on the air inlet end and machine it also to fit an anodized aluminum velocity stack to the throttle body. I do not bore the throttle body to a bigger size, it is still 40mm and use the stock butterflys. I hand massage many other parts of the throttle body also, trim the throttle shaft screws, blend the injector port into the throat of the throttle body, and just a lot of good old fashioned hand labor to speed up the velocity of the incoming charge. There is no filter or screen of any kind inside the velocity stacks. This is a racing mod all the way. It is not an issue though as many of us have ran the stock airbox gutted for years with no problems from foreign matter entering the engine.
My totally bone stock engine on my 06gp1300 went 73.4 with a 1200 grate and the throttle bodies were the only mod to the engine, no fuel controller, no headwork, stock keyway and reeds. I had rpms of 7375 and 7406 with a 1420df impeller.
I made a set for Jims1300 and his post is on the forum. He gained 110 rpm!
I am making a set for Nater785p this week for his ported motor and i expect equal or possibly greater gains for him. I will post results when it happens.
I will be offering this mod to anyone interested who has a fuel injected gp. I will modify your existing throttle bodies.
Feel free to ask any questions on the forum, PM or feel free to call me for pricing or more info..
Thanks guys... Ross 8136908373-- Rniemoelle@aol.com
03-11-2007, 09:47 PM #2
EXCELLENT WORK ROSSNEMO. i can see the people lining up now
03-11-2007, 10:22 PM #3
Ross,i talked with Jim tonight,im in for a set.
03-11-2007, 10:32 PM #4
- Join Date
- Jul 2006
Just when I thought I had all the mods done without porting you come up with a new one. Way to go!!! I just wish you would have said something about 2 weeks ago when my ski was in a thousand pieces.
03-11-2007, 10:33 PM #5
03-12-2007, 01:23 PM #6
you have another pm...show me the line...
man your going to be busy
03-12-2007, 01:28 PM #7
what is the reason for the factory air box?? have you tried them with no box at all? I dont know if I have my stock air box
03-12-2007, 04:03 PM #8
03-12-2007, 04:16 PM #9
i will put it like this i rode Jims ski yesterday and the throttle response was night and day.. killer work Ross
03-12-2007, 07:45 PM #10
Must be the drag racing background you have.
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