I have GSXR throttle bodies fitted to my Duratec, I also have two sets of rubber trumpets- two long, two short.

Suzuki use two short and two long on a bike.

What is the better combination for a fast road car Four long, Four short, or Two of each?

Many thanks



[Edited on 1/1/12 by big-vee-twin]

Here's some trumpet design info:


Trumpets

I suspect the only way to answer that question for sure would be a rolling road session trying each length of trumpet? What works on one engine may not be the best for another

I had a similar choice on the ZX9R carbs on my Zetec.

I haven't had it on a rolling road, but I can't tell the difference driving it with longer or shorter trumpets.

Stu

Trumpet length depends on what revs the engine develops maximum power, I looked into it and it seemed that for a zetec producing peak power at about 6000 revs the trumpets would need to be sticking out of the bonnet by about a foot so really the answer is the longer the better. I have trumpets about 3 inches long and the main difference they made was that they stopped the smell of fuel at high revs when it tends to be thrown out of the inlet at times.
Paul

quote:

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The one question I get asked more than any other from people buying throttle bodies is: “What length inlet trumpets do I need?”
My answer is always the same: “I don’t know”.

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Many thanks Rod, that's a great write up, I understand a little better now.

I will try with the longer ones first.