Salmacis

iTrader: (1)

This is my first post so first of all, greetings to you all :-)

I recently had my car pro tuned by a reputable tuner and the results are both surprising and disappointing. Not only are the numbers very low, the car feels slow, in fact, slower than stock in 5th and 6th.

I really wonder what the cause could be?

Some facts:
2002 Impreza STI
Invidia G200 3" exhaust
Invidia Downpipe w/ high flow cat
Deatschwerks 850cc injectors
Deadbolt TD05H-18G
Walbro GSS342
Ecutek map

The car made 297bhp/367NM on the rolling road, which seems rather low for this turbo. The tuner told me that a stock a 02-05 STI normally would do 310-320bhp on the rolling road after changing to 3 " exhaust and map. He has btw no experience with the 18G turbo.

So now I wonder what could be the cause to the low numbers and poor driveability.

Any ideas out there?

Could the map be the problem or are the other possible causes I should investigate?

Thanks in advance for any suggestions

jonathan100

hi Salmacis! i'm def no expert but on thats sped i would of thought you should be getting 320/330. by the sound of it the maps been done wrong! might be that the fuleing is off. is the turbo still spooling up in the same rev range? Are you haveing any fule cut when it comes on full boost?
Might be worth taking it back to who ever mapped it and get them to check it over.

harvey

iTrader: (48)

Where are you located.
If the person mapping your car was knowledgable/competant they should have been able to tell you what was happening and where the deficiencies were in performance. You should question them carefully.
It may be a matter of someone with a knowledge of Subarus remapping your car if your existing mapper cannot tell you in detail what might be the problem area. eg Was it taking as much ignition as expected on this type of engine. What boost is it set at and is it achieving that boost.
Is it spooling OK and where is 1 bar in 4th (on a five speed box) where in revs is max boost.
Is the engine breathing OK? What is fueling like. What injector duty cycle is reached?
What fuel pressure do you run? Stock?

As an aside, 850cc injectors are the size you use ina 600 plus bhp monster motor.

It sounds like there is a fundemental problem

Salmacis

iTrader: (1)

Hi,
Thanks for your input.
Not sure I got the defintion of spool correct, but spool has changed on 5th and 6th gear. First the turbo comes on from approx 3-3500rpm and then allmost goes back to sleep at around 4500rpm. Nothing really happens after that. 1-4th gear pulls strong until approx 5500rpm and then just keeps the power up, not increasing anymore.

Regarding fuel cut, I do not know. How do I know fuel cut occurs?

I am probably going to take it back to the tuner, just need some good arguments/questions to ask first.

Salmacis

iTrader: (1)

Hi Harvey,
Thank you for the input.

I am in Norway, and ecutek tuners are scarce over here. I was thinking of taking the trip to Andy Forrest, but funds are low after vacation and the before mentioned tuning costs, so I have to wait a few months.

I have no answers to most of the questions, but I am going to ask my tuner.

Fuel pressure is stock, that I know.
The tuner said he had some issues with too much fuel, and I suspect he did not really solve it. He also told me a GT spec type header might help, but I thought the stock one was ok for up to 380-400bhp.

I seems I may have been misinformed regarding the injectors. Deadbolt told me 750cc would be enough and my tuner told me 800cc was ok for a 400bhp turbo, which I actually told him In retrospect I realize that the 18G turbo is not a 400bhp turbo on street petrol, which is what some dealers market it as.

harvey

iTrader: (48)

Several things come through.
1) I am not sure your tuner knows much about Subarus.
2) A TD05 18G is a 360 maybe 370 bhp turbo or in that ball park and before anybody posts to the contrary, there are always odd exceptions.
3) 550cc injectors will run an05-18G satisfactorily and these are beyond optimal IDCs by 400 bhp.

Are there Scooby owners in your area that may want mapping? Where are you in Norway?
Get a small group together, 3-6 cars and send an e-mail to bob.rawle@btinternet.com and ask him if he fancies a long week-end in Scandinavia. Bob is an expert on Ecutek and will give you lots of advice in advance.

If your car is flat and from your description, it sounds grossly over fueled.

Salmacis

iTrader: (1)

1.) Well, he is supposed to be the top subaru tuner around here. A bit on the conservative side when it comes to street tune, but that is not really a bad thing.
2.) Yes, you are right. I got blinded by the marketing figures.
3.) So I guess 650cc running stock fuel pressure would be more appropriate for the 05-18G?

Thanks for the tip, I'll check on our local Impreza forum if anyone is interessted. Whereabouts is Bob located?

And yes, I think you are right about over fueling. Especially since the 850cc are much too big and the issues my tuner told me about.

borat52

Just out of interest what boost pressure is your car making?

jonathan100

Fuel cut would happen when the car starts to come on boost and the ecu cuts the fule to protect the engine from damage. as the car starts to boost it would feel like someone has just slamed on the brakes for a fraction of a second kind of like hitting a brick wall. hope this helps

bruce

iTrader: (5)

re read original post!!

Salmacis

iTrader: (1)

Not sure, I do not have a boost meter / ecutek data monitor at the moment.

My tuner told me he'd go up to 1.5bar at the most on STI when internals remain stock, so I suspect that's what he did on mine too.

I will try to get him on the phone tomorrow and clear a few things up.

Salmacis

iTrader: (1)

Thanks jonathan100

Then fuel cut does most definetly not happen to my car.

StickyMicky

silicone inlet pipe sucking closed?