Absolutely epic results here for one of Doug Stirlings escort cosworths!
Background was that it was a bit of an evolved spec over time, it had an NMS head and NMS cams on a Dave Pitchard built bottom end running on L8 and mapped by NMS on a GT3076 turbo on a .63 housing, made respectable power but Doug felt it was too laggy (TBH it wasnt *that* bad IMHO, you just needed to keep the revs up when driving it and it went well, and was still a massive leap forward from the old T4 it had before that anyway!).
Doug took it to Mark Shead at MAD and gave him carte blanche to change anything that he felt was appropriate with the aim of not losing top end power but gaining spool and responsiveness as that is what Doug is really into with his cars. Power before was tested at 480bhp IIRC (will try and get the graph off doug when I see him next or see if he can email me it)
Mark removed the water injection, ditched the cams in favour of some of his, fitted one of this new spec-r intercoolers and fitted a vipec ECU and remapped it with a GT3071.82 instead of a GT3076.63
Not only has it massively transformed the bottom end torque (at one point in the rev range IIRC it made 190lbft more than previous due to the earlier spool) its also gained power on top as well:
Here is the graph how it stands now:
It ties in now finally with how much power MAD get from the same turbo on an Evo engine as this is the first GT3071 they have done on a big spec head and latest specR intercooler, all their other 3071 conversions have been on more standard cars, giving around the 470bhp or so mark.
Interestingly Doug's engine is still low compression, 7.2:1 in fact, so the top end power could possibly edge up a little more form a raise in compression too.
Hopefully I'll get a chance to take it out for a spin on sunday if Doug has it with him when I see him, should be manic now on the 3.9 gearing as it felt pretty reasonable even before.
PS, when they tried edging the boost up to 2.7 bar, it made 522bhp and 520lb ft! but still tailed off to the same figures at the top end as the turbo just cant maintain the boost at high RPM as it really is flat out at that