My BW S475 project... lots of pics.
Yay, first startup.
Yepp today was a good day, got to hear some rotary sound at last!
http://www.youtube.com/watch?v=zK4X8q1OilE
http://www.youtube.com/watch?v=zK4X8q1OilE
just did some dyno pulls and the car put down 595whp@22-22.5psi, peak hp at 7160rpm, having some problems with boost, it wont hold up.
Ill post some logs for you when i get home and maybe some of you gurus can help me out
i just passed 100+ dyno pulls with this engine
Ill post some logs for you when i get home and maybe some of you gurus can help me out

i just passed 100+ dyno pulls with this engine
Ok, here are a log from one pull.
green line = boost (in bar)
red line = backpressure (in bar)
As you see im losing boost... is the backpressure causing this?
im using the small valve seats (28mm) and their 60lb/inch spring (the hardest one)
It is set up like this (http://synapseengineering.com/smf/in...d57&topic=97.0
Im also using a HKS HVC (IV) boost controller, i can't say im very familiar with it.
Oh, im still one the 3" exhaust.... :/
I don't have any experience with your wastegates so i have no clue about them...
I would try disconnecting them and setup some sort of boost limit on your ecu or stay very alert and watch the boost and see if you can get more boost without it falling off..
I don't believe you have to much backpressure. you have roughly 28psi back pressure with 22.5psi boost. That's not bad at all...
I would try disconnecting them and setup some sort of boost limit on your ecu or stay very alert and watch the boost and see if you can get more boost without it falling off..
I don't believe you have to much backpressure. you have roughly 28psi back pressure with 22.5psi boost. That's not bad at all...
i've got some more combinations to try on the wastegates, they've got some kind of internal boostcontrol letting you choose different ports for different boost. Ill try the highest setting and just run it on the springs..
Sent a mail to synapse, got a fast reply.
"Gustav, sounds like you are overwastegating. I'll look at the logs when I get back to the office.
Peter
Sent from my iPhone"
i guess this means that the valves can't keep closed?
"Gustav, sounds like you are overwastegating. I'll look at the logs when I get back to the office.
Peter
Sent from my iPhone"
i guess this means that the valves can't keep closed?
I had a feeling your wastegates were the problem...
Hmm appears to be losing boost at the end of the pull. Does appear to be backpressure maybe blowing the gate open. Does your unit have the 96mm turbine wheel and 1.32A/R housing?? Most of the cars I have worked on with that turbo don't have much of a problem. Also have you got a restrictor on the oil inlet on the turbo?? I have worked on 2 FD's running Borg 475's that ran restrictors...killed the turbos less then 100 miles. Borg's like plenty of oil...



Hope it sounds really mean
Looks good anyway


