Hi
Been directed here by a fellow member after some disappointing results last week. I have a JDM Hatch GT, 2l which obviously came with the tiny square TMIC. I got a decat pipe, PW Verticooler and Cosworth panel air filter hoping to increase power on the dyno run I had in Sept 2020 given it should be 250bhp standard and ran 247.

First of all, fitting the decat I found the flange was much different. Contacted the supplier who said mine looked like a Legacy GT Spec B set up? So to be ready for the remap, decatted the cat and fitted the verticooler to then sort a decat pipe. Again, problems with the hot pipe as the turbo is different but all fitted. It has a VF47 turbo fitted which may be part of the issue.

Came to mapping at Scooby Clinic and we started about 236bhp. They tweaked and played around with it but only managed 252bhp max after several runs. Had a chat after given it was meant to be 250 as standard. They took it for a test drive, found no problems at all, took a camera to the turbo and again, nothing of concern. They also checked the exhaust system and were happy it was free flowing. No air leaks but turbo wouldn't hold boost. Been told this is normal for the VF47.

I have asked around on Legacy FB group and the general consensus is that the turbo would max at around 280bhp but others with the 'same car' managed over 300.

Did the S-GT come with different turbo setups?
Is there an alternative to the VF47 with the same flange fitting?
Can anybody offer any other advice on why the power output was so low? Even 270 would have been a bonus in comparison.

Right now I am in 2 minds to go back to standard given the price of the cooler and instead go STi TMIC and different turbo or sort a proper decat pipe and turbo given the cooler should he the best TM option. I didn't want to go mad on the engine as it is a daily but I would have liked over 300hp. But I am now wary of spending more money to not get what I expect of it.

Any further help or advice appreciated.


Dyno 2020


Engine before (dyno 2020 run)

Engine bay now

Last weeks remap

 

I'm sure the mapper would tell you if there was any other limiting factors beyond the turbo when he mapped it, injector duty, fuel delivery, not enough air, timing, knock events, actuator strength etc. So if he didn't mention anything else I'd say listen to him and look at a better turbo. You could always have another chat with your mapper and ask if there was any other issues or limiting factors but it sounds like he's already given you your answer

 

Doesn’t sound right to me

 

When I had an S-GT it made 289 bhp with only a full Mlltek 3" system, with a 100 cell cat in the downpipe, & a panel filter, mapped by Paul Blamire @ Zen. it only had low miles on it at the time,
Have you had the engine health checked, as in leakage & compression readings.