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General => The garage => Topic started by: Starry on 05 April 2004, 20:19

Title: fmic pipe sise
Post by: Starry on 05 April 2004, 20:19

what are the pro's and cons of the size of tube you use on your intercooler. i am using 2"/51mm tube on my fmic at the mo and was wondering what ,if any the benifits of running larger tube would be. i am running revo/turbo back mitek and my figures are 199bhp/237lbs..

Title: Re:fmic pipe sise
Post by: turbo on 06 April 2004, 04:12

from turbo to intercooler.......... and from intercooler to throttle...........

i would just say use a diameter which fits over the turbo outlet and the intercooler inlet........

you wont get any benifit by running a bigger tube as
the turbo outlet hole and inlet hole on the intercooler will restrict any gain from this!

as far as i can see i soppose this is how it would work....

plus at the end of the day the turbo can only ram so much air in the engine.....


you can buy a boost valve which will allow you to run higher boost pressures over factory pressure........ ie keeping the wastegate closed (waste gate is a little flap inside the turbo which controls the boost pressure by opening a flap which allows air to bypass the turbo) the depending on boost pressure.... there is a presure which you can go up to...
ie say standard pressure is 10psi you may be able to run it 1 or 2 psi more without any problems......

but unless its set up to cope with the higher turbo pressure, ie compression ratio, fuel timing, igition timing etc its lible to go bang.......it may first blow the head gasket....or it could blow the piston rings off............

theres some info for you........ :)

ps my bro's mate had an uno turbo and he knew someone who fitted a boost valve to i think it was a montego turbo.....and he unscrewed it all the way ;D

he said it flew up the street and went bang! ;D
fun while it lasted! :D

Title: Re:fmic pipe sise
Post by: Starry on 06 April 2004, 08:44

thanks mr vw.
as i said i am running 2"/51mm tube do you think this is an ok size for the car/setup i am running. as i dont want to restrict the air flow to my turbo.. i know by running a fmic i will be getting nice cool air without heatsoak but will i get enough, or is this to hard to work out. thanks for any help..
 ???

Title: Re:fmic pipe sise
Post by: mk1 on 06 April 2004, 18:30

You can check to see if the pipework is restricting the air flow by putting a guage on the outlet of the turbo and comparing it with the pressure in the inlet manifold. Not sure what you should get, I think you should be aiming for only a couple of psi drop. Just measured my pipe, 54mm od, don't know why I went for that size but it seems to work ok as I have over 200hp  ;D.
Steve.

Title: Re:fmic pipe sise
Post by: Starry on 06 April 2004, 20:48

200bhp is were im at but just wanted to know if you could check if it was working to it's fullest. ill have to find someone with a gauge near bristol. cheers Steve

Title: Re:fmic pipe sise
Post by: mk1 on 06 April 2004, 21:12

Pretty sure that you are ok with the pipe sizes, what size is the turbo.
Was checking my car over tonight and had a idea, fit the outside air temp sensor to the inter cooler to see what the temp drop is from one side to the other  ;)(may have to extend the wires to reach the left hand side). Will post to let you know how it goes.
Steve.