ARRON BIRD

Is the standard lambda sensor ok to fit in a different downpipe in other words will it need a motorsport spec oxygen thingy ????????
Somebody mentioned it to me today...not too good with mechanics......told me that the heat and stuff may cause the check engine light to come on.
I dont want un-reliability but a bit more power.
Can anypne shed some light?

spudgun

aaron
i too know jacksh1t about mechanics, but when i had my downpipe done, as far as i'm aware they just transfered the bits and bobs to the new decat downpipe. when it went in for ppp, they transfered it back to the original downpipe, waste of money really

ARRON BIRD

Spudgun..............you lost me m8
You changed your downpipe back to the standard one when you had the PPP fitted????
If so why???

CraigH

Arron,

It just bolts in the new downpipe.

Stef

I've got an aftermarket d/p with my PPP and it seems to go quite well.
Just get it done Arron, you'll notive a vast improvement. It will only affect the warranty on the exhaust as well.

Stef.

MikeWood

Aaron

Be careful.

I have driven P1s with different downpipes that det slightly. Any damage caused would definately NOT be covered under warranty.

Mike

ARRON BIRD

Mike what are you saying mate. Should I not bother or are you suggesting a certain make.
Ring me on my mobile if you dont wanna name names on here.
I want a bit more power but cant be doing with ANY unreliability!

pat

Aaron,

the PPP pushes the envelope of the map somewhat closer to the limit, adn is designed with a particular exhaust back pressure in mind. If fitting an after market DP alters the volumetric efficiency curve of the engine, this could lead to leaner running, more heat, possibility of det...

Not really an issue on a UK car since they are very conservatively mapped, but on Jap spec (which the P1 essentially is, with a sports cat) it can get into det. Keep an eye on it, and either fit a more restrictive DP, get another ECU or use octane booster if it is problem.

Cheers,

Pat.

ARRON BIRD

Getting put off now...
Why cant it be simple
Mike would appreciate your comments on this.
I`m not messing with another ecu or induction kits or anything.
Just wanted a bit more power and a little more noise!

MorayMackenzie

ARRON, (in caps, of course )

You don't get more power without affecting the operation of the ecu... simple as that. If you change the downpipe, it will reduce restrictions in the system, allowing gasses through more efficiently... ecu tries to up fuelling to compensate, but the map was setup for a certain spec of hardware... you have changed this... hence problems.

Your european (neutered ) STI runs it's ecu map closer to the edge of engine "safety" than a normal european turbo... hence fitting a downpipe is more likely to cause problems.

You could fix all this by changing to a link or motec ecu... but there goes the warranty... such is the way of the tuned car.

Moray

Bob Rawle

Arron, listen to Mike Wood, the P1 WILL det if a different downpipe is fitted due to the fact that it will run with more peak (and maybe held) boost. If you decide to do it then you MUST run the car on 97 octane fuel with octane booster to achieve a minumum 99/100 octane. Since the P1 is based on the STi version 5 "Japanese spec" car then the same general rules apply.

Bob

[This message has been edited by Bob Rawle (edited 23 March 2001).]

ARRON BIRD

Thanks for the reply`s folks. Think I might wait a bit as it seems a lot of guys on the BBS are fitting them to P1`s. Think I`ll wait to see if any get DET and engine problems. I always run my car on 97 RON fuel anyway but I`m sure that it still DETS sometimes under certain conditions so if fitting a downpipe is going to make this worse then I think I`ve had my fair share of grief with the car already. It`s quite nice at the moment to actually enjoy owning it

Jake

Hasn't the P1 got enough power in standard form??????!!!!

Stef

Is the only way to tell if your car is detting to take it to a rolling road? I can't hear anything untoward with mine, but I'm getting wooried now with my full catless exhaust, induction kit and PPP ecu.
I think my restrictor thingy may need adjusting as well, as the car sems to overboost slightly. Where can I get this sorted?

Stef.

Deep Singh

Would'nt the answer be to spend another £140 and fit a detlink with the downpipe?Then if you get detting you can remove the downpipe and probably sell it for a decent price on BBS.The detlink you will have paid for will still be a useful asset even on the unmodified car if just to set your mind at ease.Probably something really stupid about my suggestion........

dowser

Bit of a late follow up, been in Oz - but my ppp'ed my00 overboosted occassionally once I'd fitted an SS d/p.

More worrying was that peak boost (1.35 bar) was being held for around a second before being clamped by the feedback loop.

I fitted a knocklink and can confirm that (so far!) the peak of 1.35 bar is not causing det

I haven't hit overboost with the knocklink yet, but will report once I have.

Another interesting thing; I fitted an OE STi backbox while waiting for the knocklink - this added enough additional backpressure to fix the overboost Refitting the Prodrive backbox sees *huge* gains in performance

So while a backbox makes no difference on a standard car - once you remove the OE d/p or play with the ecu it really does become the weakest link!

Richard