Hi Guys

Currently running a 03 STi with a few mods (decat, fuel pump, air filter 3 port boost solenoid etc) and had a Tek 3 remap by Bob Rawle from New (once it was run in of course!!)

Car has been great and apart from genaral servicing and tyres it hasn't missed a beat.

Time now for a change and looking at a new 06 STi and again I would decat etc and Tek 3 remap by Bob (sack the warranty, lol)

What sort of BHP/Torque figures could I expect from the 2.5 motor? I'm trying to compare it to my 03 STi, I know I shouldn't as it's a different beast but trying to get some idea. Perhaps it's a question Bob could answer!!

Thanks you help in advance

SB

 

Hiya,

I think that's a question you should direct to Bob mate. My suspicion is that you might not gain much over your current car in terms of headline figures, but it will be torquier owing to the larger displacement. IIRC Many tuners seem to be quite wary of the MY06 2.5, saying that the std Pistons don't like over 350bhp

Have a word with Bob though, he's the expert.

Ns04

 

Thanks for that.

I've read a few threads regarding the pistons, not sure how true this is but could someone clarify this for me? Perhaps the JDM spec, is the way forward!!

I don't wanna spend £30k on a car which is no better than what I have which I'm sure you will all understand.

All comments appreciated folks, perhaps some comments from some tuners would be good.

Thanks Guys

 

As long as the engine is kept "within bounds" then the car will react very well to your proposed mods. decat and remap will nicely get you well up on std and better than the PPP. No need to change the std panel filter even.
Unfortunately the 2.5 was thought to be as robust as the 2.0 but due to the piston design this is not the case, a lack of appreciation of this has caused engines to fail but, as already mentioned, kept sensible you will still get very good gains over std and good gains over the PPP. Fuel is key and Optimax is the way to go.

best

Bob

 

Bob

Many thanks for the info. on this and if I do go down the route of another Scoob I will be on the phone to book it in with you.

Just another piece of advice from you if that's ok, I've been toying with the idea if a JDM or spec C as from articles I have read they have Twin Scroll etc and some other bits n pieces. If I had one of these remapped with decat etc against a remapped UK car would you have any idea what the difference in torque/bhp between them?

I know it's quite a loose question but I'm trying decide which route to take, UK or import.

Thanks for your help.

Ian

 

JDM cars do seem a bit easier and less costly to extract bigger power from. The equal length headers and twin scroll set up is also supposed to produce very good spool up etc... But you loose the Scooby burble

Have a look in here mate:

http://bbs.scoobynet.co.uk/forumdisplay.php?f=376

A relevant extract (although this is not a like for like comparison and it's not a 2.5 UK car) I suspect the differences would be significantly smaller with the 2.5 and that the 2.5 might even be superior in some parts of the rev range.

Again, Bob is the expert though!

Ns04

JDM Vs UK
Perhaps an unfair comparison, but a useful one!

OK.... so a JDM car (especially a SPEC C) differs from a UK car, but what do these differences mean for the driver?!

http://bbs.scoobynet.co.uk/images/sn...9vsuksmall.jpg
TEST 9 Vs Modified UK STi

As you can see in the comparison graph above, the JDM car produces so much more power throughout the rev range (both bhp and torque), is quicker to create power/spool quicker and also drives so much better on the road. The greatest contributory factor to this is without doubt the twin scroll and equal length header setup of the JDM model. It is also worth pointing out that the UK STi comparison shown above, was modified greater than the JDM car (different turbo as well as similar breathing and exhaust mods as this article) and subsequently cost more to modify to this level.

While peak figure comparison shows +7.5bhp and +27.95lbft advantage to the JDM car, the JDM car shows increases of over 55bhp and 80lbft in other parts of the RPM range! These gains are big in anyones book and further concrete the fact that when comparing power figures you should ALWAYS compare the whole rev range and not just peak figures.

 

My MY03 JDM STi Spec C on the original JDM Map running optimax and octane booster, standard exhaust, hayward and scott 3 inch back box and an STi panel filter, this car has consistantly run over 312bhp, last run (all increasing slightly as the engine runs in still ) was 318bhp and 356lb torque.
Tuned your looking at (with associated mods like exhaust) around 360bhp and 380+ lbs of torque.

Tony

 

Thanks for the info. Tony and NS04 and appreciate your help on this.

This is all food for thought and the JDM STi is looking favourite. May I ask a stupid question, Is the 06 JDM a 2.0 or 2.5 lump. I just can't find this info. out, was gonna call Litchfield today but ran out of time in the office.

Thanks

Ian

 

Ian, The Japanese cars are 2.0, feel free to call anytime with any questions as we have both new and used MY06 JDM STIs in stock. We also have a number of UK models in at the moment as well

Iain

 

Care to show us your torque curve, something tells me the peak figures quoted don't quite tell the whole picture If I were to quote siimilar from my VF37 equipped JDM STi I could mention 409lbft but I wont

P.S. You quite sure on this 360/380 business??

 

Iain

Thanks for that, I thought they were 2.0 which is good news.

You may well be getting a call or a visit, your only 1 hour away from me.

Cheers

Ian