Twin 45 Trumpet Size?

[spark-plug 1]

Ive get a 1.9gti and was wandering what trunpet size i should go for on 45 carbs ive also got a big valve ported head ?

[MrG 3]

the trumpet length is dependent on filter type used really as you need a clearance inside the filter of at least 30mm, so the length is dictated by that. For eg I have 80mm deep K&N filters on mine and have 40mm deep trumpets

[spark-plug 1]

I have itg filters which are 130mm deep soo i should get 100mm trumpets! ?

[MrG 3]

I have read/heard that the length used can affect the engines torque and how its used? Perhaps a more knowledgeable person will enlighten us to this if its true?

[spark-plug 1]

Yep been told that lots too hense why i asked somone on here must know?

[wracing 19]

That is true, it can make massive differences, but I think it needs back to back testing on the dyno to select the perfect length. Your best bet is to go with what has worked well for others if you don't have the time for dynoing!!

 

Thanks

 

James

[Baz 421]

Something around 40-60mm usually, especially as that's all that will fit with the standard slam panel etc arrangement.

Edited April 9, 2010 by Baz

[Sandy 191]

The overall tract size and shape influence the inlet tuning collectively. But if you're using a fairly normal DCOE inlet and carbs/bodies, about 350-370mm from the inlet valve to trumpet mouth is a good starting point for testing.

[spark-plug 1]

ive got the slam panel too had to be cut to get the filters to fit by the looks of it spose that isent the best idea lol

[Slavesta 2]

My frend has 120 mm trumpets.