RT

My local garage just retrofitted the new STI SpecC's setup into a bugeye JDM STI7. The boxer beat is gone, but the car is reportedly much more responsive, plus less laggy.

However, that car doesn't have a KL installed. Just wondering if anyone else has tried the same as I've heard some reports of det with std ECU settings on japanese aftermarket manifolds. Top end/high boost det could quite easily by fixed by WI or simple ECUTEK adjustments. However things like transcient det and "lift off" det etc may be a little more tricky.

Thoughts anyone?

AlexM

Yup - I would expect this kit to require a remap to be safe. Changing the manifold and turbo have got to have a significant effect on the fuelling required, surely?

Cheers,

A.

carlos_hiraoka

RT, can u post pics of this parts, and what are the prices like of the new twin scroll turbo, manifold, etc

carlos_hiraoka

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Pavlo

ECU should cope with the fuelling changes as it's a closed loop system.

Sti7 should be monitored for det anyway IMHO, as there appears to be plenty of standard cars with problems.

Paul

Adam M

I thought they ran open loop on boost and closed loop on cruise and idle?

RT

Sorry I didn't take any pics. But the stuff is quite standard, and if you do a Google Search for the new STI Spec C, you should be able to find something. All the bits bought were brand new, and I'd expect the cost to be approx GBP3000. Not cheap. (Bits include uppipe, downpipe, twin scroll turbo, exhaust manifold, turbocharger, engine oil sump.)

Also, I'm pretty sure the fueling is open loop for all transcient conditions. Its only closed loop for constant throttle cruise and closed throttle idle.

Pavlo

Yeah adam I didn't mean closed loop like that. i guess it's open loop anyway. What I really meant is the fuelling is metered relative to measured mass airflow. So changing exhausts, turbos, even cams are well catered for as the ECU knows about any extra airflow.

It's a misconception that putting on something like an induction kit will lean the fuelling due to better airflow. What it does is change the operating point on the fuel/ignition maps. This may be mapped richer, leaner or the same.

Paul

RT

Exhaust manifolds affect how "efficiently" the combusted gases get pushed out the combustion chamber. This in turn would affect refilling characteristics, no? Perhaps this is why some cars run into det problems with aftermarket manifolds.

The MAF-Timing-Fueling relationship would be calibrated with the OEM inlet and exhaust characteristics in mind. The MAF sensor is very far upstream along the air inlet track, so any hardware changes downstream of the MAF sensor would potentially throw this calibration off.

[Edited by RT - 3/31/2003 10:33:43 AM]

Pavlo

improved exhaust breathing would tend to improve cylinder filling, but also reduce exhaust pollution of the cylinder and cylinder temps.

It doesn't matter where the MAF sensor is, it measures all the air going in. If more air goes in, it knows about it.

I would be more worried about the suitabilty of the standard map than anything else.

But if you get 10% more airflow at the same boost, the ECU will know about it.

Paul