3800 FWI pipe sizes...

[zeez gtp]

http://www.johnvegas.com/Fwi.htm

i found a good write up on how to build one. I just want to make sure that 3" is not to big or not to small. It seems like it is a good size. hopefully this will get done on sunday. thanks

zack

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[imported_Ron Vogel]

3" is too small. If it is 3" it will only work if it transitions to 3.5" at least 4-6" before entering the air horn. I tried a 3" FWI, and it choked off the motor above 4000rpm. If you need 3.5" pipe, I can get it pretty cheap in steel, but only up to a 3" in aluminum from a local guy.

 

[BumpinGTP]

there are some people that have 4" fenderwell intakes

 

[imported_Ron Vogel]

Hey, you can make it as big as you want to. Just not smaller than the air inlet on the TB. The advantage of a bigger tube is the engine has more volume inside the tube to use before it asks the filter to suck in more air. However it really is best to use the same size inlet as the TB right before it. If you run the TB with no screen, and the tube doesn't match, it affects the MAF performance.

 

[zeez gtp]

so try and get a 3" off the tb, and right after that maybe go to 4" for the rest? i am going to use my 9" K&N cone. i think that has a 4" outlet/inlet, whatever its called. ron give me a setup of what sizes should go where. cause obviously i would of installed it just like the link and then would of had bad airflow. thanks

zack

 

[BLK00GTP]

Does anyone know how Big the piping is on the Speedbuilt FWI that sells on grandprixstore.com. They never said what diameter it is.

 

[zeez gtp]

i always wondered the same thing. it doesn't seem to be that big