Originally Posted by
J1mbo
Hi mark
Why would you change a engine spec which you want to do the job when the turbo isn't upto it?
We wanted the engine to make full boost by 4k peak at 8k and be able to hold its power till 8.5 or higher.
The engine was amazing the turbo was useless on this spec we wanted/needed for the car. (150mph gearing at 8k so needed a little extra for the long straights..)
Put a t04z on it and it made full boost at 4.2k revved to 9k and made 40bhp more without a whisper of surge. No need for the compromise in this case.
I have no doubt you can make a gt35 work but I don't think it suits what we do with the yb as you have a very different outlook on them and they work with the specs you like

Unfortunately for the guys out there who may not be putting it onto a engine completely specced for it, your going to have a horrendous time IMHO!
Jim
Or was the gt35 amazing and your engine useless as it couldn't consume the air being forced in? Only joking but it does serve as what ideally is needed is to match the overall spec. No engine/turbo can be useless, it just didn't meet your requirements.
Just to be awkward....do you not class your 200rpm over target threshold as a compromise?
Did you try capping the 35 back til 4.2k and checking for surge?