09-17-2014, 08:40 PM #1
performance question, data does not add up.
I just tested out the new solas svho prop and I downloaded the log file from the test. I was out for 20 minutes and saw a max speed of 83 mph at 8500 rpms. (I don't care that the speed was down because I tune it yet.) What caught my attention is my max throttle position was 62% and a max boost of 196 kPa which equals 14PSI??? at 8500 RPM the wheel should be producing 219-226 kPa or 17-18 psi. Is my throttle body not opening all the way and this is why the boost is down?
09-18-2014, 06:47 AM #2
I would guess the TPS is not configured correctly, as you probably wouldn't be achieving that much rpm with that particular setup at 62% throttle opening. I would double check all of your intake coupling points for a potential boost leak, as well as your BOV. If the ECT is your engine coolant temp, that seems a little high, depending on what cooling you're running. You're nearing 200 degrees (199 pictured) and that additional heat probably isn't helping performance. You may even have a limiter relative to temp that may be causing an issue. I'm not familiar with your ecu, just basing my thoughts solely on the screenshot you posted. Keith
09-18-2014, 12:32 PM #3
Yes that's what I was leaning towards, but on previous logs it showed 100% at WOT runs. I have noticed recently that I have a high idle problem but it if blip the throttle a few times it goes down to almost normal, I'm going to take it apart and try to clean it tomorrow, I hope I don't break anything because I'm going to try to go on the group ride Sunday morning.
The ECT is my temp. It is high and it gets up there when I'm doing ALOT of WOT. I may have to go through the cooling system to see why it's getting so hot, My rev limiter comes down to 8,000 at 100c
Thanks for your input any and all comments/advice is always welcome
09-18-2014, 09:05 PM #4
I just removed everything from the intercooler to the intake manifold, I replaced all the clamps with the bolt through style and sprayed the throttle body down, the flapper looked perfect inside and it would open and close just fine using the throttle. Is it possible that water got inside the cover of the throttle body? I did have a fair amount of water in the ski a few months back when an intercooler line blew off. I'm missing my T20 security torx bit so I didn't open it up.
The intercooler had a little bit of water sitting in the bottom so I dried it up and water pressure tested it and the water didn't come back after a few minutes so that's not the issue. All the hoses are tight and everything is reassembled so I'll have to try it out tomorrow afternoon and see if anything changes.
I should mention that when it put it in the water yesterday it wouldent rev at all even if I pinned the throttle it was still at 2200 at idle, I had to keep pinning it and letting it go quickly and I would gain about 300rpms every time I did that. After about 30 times doing that I finally got all my rpms back I think.(That's why I though the flapper was stuck)
Plugs are good, compression cold Is between 120 and 130 and there is no warnings or codes in the vipec log
Any other ideas?
09-19-2014, 06:51 AM #5
If you're having those problems with the throttle responding, you may also want to check and clean your connections on your your "accel position sensor". Factory part #6D3-14305-21-00. It looks like this:
09-19-2014, 10:45 AM #6
I'll just change it if I still have the problem later today. That's one of the perks of always having a work in progress ski.
09-19-2014, 06:42 PM #7
09-20-2014, 05:53 PM #8
No more throttle problem, I took it out and everything is normal except now it sounds like I'm hitting the rev limiter at WOT but I'm not reving anywhere near it?????
09-20-2014, 07:22 PM #9
Forget sounds!!! What's your RPM and AFR!!!
great football games on today
09-22-2014, 03:24 PM #10
There is definitely something up with this full throttle rev limiter like feeling, the ski is pulling hard from a dead stop up untill it starts to hit about 8500 rpms, then it sounds and feels like the rev limiter is kicking in. If I back off maybe 15-20% of the throttle the limiter feeling disappears and ski picks up speed. It's definitely not the rev limiter, even the logs show I'm a minimum of 500 rpms away from it. Could the motor be running out of fuel? I think it happens more noticeably when the motor is colder.
I don't have a fuel pressure sensor but I don't think it would be the worst thing to install one and hook it up to one of the analog inputs to log.
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