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Best Simple Upgrade - Downpipe Only

967 Views 6 Replies 5 Participants Last post by  yasir
Pardon my ignorance. I've read a lot about the BPU thing. It seems to me that the one obvious upgrade is just doing the downpipe.

Correct me if I'm wrong, but this removes both of the CATs, so gives a nice power upgrade. It does this without the complexities of wiring-in boost controllers, and the fuel-cutoff defeating that is then required. I nice thing for someone looking for a boost but who doesn't want to "mess" with the car too much.

Again, correct me if I'm wrong, but the only downside is that the Supra TT has 2 O2 sensors, and all the downpipes have facilities for only one (why????), which causes your check engine light to come on. This SUCKS, of course. Now I hear of a "black box" that fixes this one drawback?
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A down pipe is by far the best bang for the buck, but you will hit fuel cut in cool weather thus a BCC is also required.

You only get a check engine light on the OBD-II Supras.
So that's all there is to it, eh? Downpipe and a "BCC" to prevent fuel cut off.

Everyone agrees with this?
dizzy said:
So that's all there is to it, eh? Downpipe and a "BCC" to prevent fuel cut off.
Everyone agrees with this?
You also need some method of raising your boost. A bleeder-T or clamp-mod will work fine.
pwpanas said:
You also need some method of raising your boost. A bleeder-T or clamp-mod will work fine.
If he wants to raise boost a good, cheap solution is a ball & spring type MBC, like the www.dawesdevices.com ones.

He will still hit 13~15 psi through 4th gear, maybe more in 5th, with only the DP and the stock hose configuration.
If you do one mod on the Supra TT, it's the addition of a true downpipe. However, like noted above, the Greddy BCC is also mandatory with the DP to avoid boost cut. I remember hitting 15 psi without touching the hoses after I had a DP on my old 1994 TT 6 speed.

Steve T.
I never hit the fuel cut when i had the DP & the Exhaust :rolleyes:I was boosting about 14psi & may be an intake would have done that.
Later, Yasir
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