13 replies to this topic

[tinhow]

Anyone ever tried to mod the throttle body coolant bypass? Was reading up on this, supposedly it will lower intkae temperature and free up some horses. It was done on a 2002 WRX but I reckon the 02 B4 should be able to be modded this way also.

[RX25SE]

I'd be looking further into this. Usually a coolant supply to the throttle body is for the air bypass valve. This allows extra air to bypass the throttle body with a cold engine to increase the cold idle speed. The valve is controlled in a similar way to a coolant thermostat and requires a flow of coolant to work. Once the engine is warm the valve is closed and idle is controlled by the IAC valve. BUT, I have never looked to see if a suby has this system, hence more research.

[Delete This Account]

I did it to my old car (EJ25 RX) didn't notice any difference at all, i don't think its worth it

[buzzda]

Nice pic Walts What size BBS's ya got there? Front wheel needs moving foward to give some castor

[Delete This Account]

Nice pic Walts

What size BBS's ya got there?

Front wheel needs moving foward to give some castor

Just the 17" BBS's, all you need to do is get out the hairdryer warm them up a little bit then stretch them out by hand

[buzzda]

If I just go REALLY REALLY fast, will the the centrifugal forces stretch them??

[Delete This Account]

If I just go REALLY REALLY fast, will the the centrifugal forces stretch them??

Yes

[Chadza]

although your wheel speed MUST be equal to your engine speed otherwise the size increase will LAG.

[alexGT]

i did this mod on my old wagon. i couldnt really notice that big of a difference but i guess it might help in the hotter seasons. it is extremely simple to do once you've got the cooler off.

[RX25SE]

I did it to my old car (EJ25 RX) didn't notice any difference at all, i don't think its worth it

i did this mod on my old wagon. i couldnt really notice that big of a difference but i guess it might help in the hotter seasons. it is extremely simple to do once you've got the cooler off.

Did either of you two notice a difference when the engine was warming up from cold?
ie. Higher/ changed idle speed?

[Delete This Account]

nope there was probably a very minimal change but not noticable

[alexGT]

mine was slightly different. coolant still runs thru the IAC but from there it was another hose through the throttle body unit then back around to the aux coolant hoses on the cross over pipe. i just disconnected it from the throttle body and ran it straight to the aux lines.

[RX25SE]

Thanks.

[CRUISN]

Mines been bypassed at the throttle body AND the iacv. Idles fine.