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yes correct about the Inlet temps, as almost all of our runs on the dyno started on 25C and ended at 32C at the end of each pull. Good fan in front, but still not real life.
its a bit drizzly here today, but ill manage something
yes correct about the Inlet temps, as almost all of our runs on the dyno started on 25C and ended at 32C at the end of each pull. Good fan in front, but still not real life.
its a bit drizzly here today, but ill manage something
If the DD run was in Shootout Mode, it is not corrected for temp, etc. so that temperature difference vs your road pulls (at approx 10C I guess?) will account for the difference. I would actually have expected the DD to be even lower compared to the VDR.
Check the shapes of the curves too. That will tell you much about the load on the dyno vs. what the car sees on the road.
How do the numbers compare to whp from your own Performace Box derived program, using the data from the same 327whp VDR pull?
1995 RS2 on Alcohol (6.8sec 100-200km/h)
1994 80E Avant
1986 2L Golf 2 on Alcohol
i have never hooked up the perfomance box measured run at 1.4bar which is where the 327 VDR number came from.
the car was on modifyable load during specific bin mapping, and then for the high boost runs, it was on a shoot out mode with a higher specified load so as to mimic similar conditions to a higher gear pull. That way we could see the highest EGTs without actually having to do the pull on 5th for example.
at the same time, we didnt spend too much time on configuring the boost settings as i knew this was something that would take a lot of time, and id rather i did it gradually and on the road where everything is cooler.
i had a go to fix the spikes. i managed to get it a bit better. Got rid of early oscillations and got some more later on, but less felt.
i have to see how i will get around this, im even considering a less stiff wastegate spring as you can hear the wastegate opening and closing while trying to control boost.
long runs yesterday. No decent boost curve though, so unfortunately nothing to report yet.
After changing a wastegate spring and a mac valve, i noticed that:
1) both my 3port valves on occasion got stuck, as if no function at all. Getting only 0.3bar of pressure (with oem spring) then all of a sudden, unstuck again and pressure is building up.
2) my stiffer spring was probably having something to do with the oscillations as well, as it was stiffer than the 1.9bar that 034 has, and pretty much an on-off feel.
3) My OEM spring showed that most of the times my DC was maxing out in order to just keep 1.4bar of boost.
SO:
plan is to fit the 4port solenoid, and i have already fitted the 034 1.9bar spring.
I will retune an open loop boost control from scratch. Get the desired boost i want, then get the targets and PID setting in as well. Hopefully ill get a nice boost control that way and obviously log some runs.
Ok, too bad you didn't get a clean run, but the initial dyno run rhymed very well with your VDR data, especially considering that the ambient temp was likely quite a bit cooler on the road. My newly aquired data from a car that pulled 515whp on a Mustang dyno doing 501whp (509wps) on the VDR shows us that so far, the results are very close to those off a good dyno, and quite conservative. The tuner who did the Mustang dyno run uses a fixed 25% loss for quattro, so that car is rated at 686hp/697ps at the crank, which is somewhat overstated in my opinion. 630-660hp range is more likely, but who cares. Crank hp is about as relevant as hp inside the cylinder. It is the hp (and torque curve) that reaches the ground that moves the car and has value for comparing and calculating performance.
1995 RS2 on Alcohol (6.8sec 100-200km/h)
1994 80E Avant
1986 2L Golf 2 on Alcohol
right,
well a few hours later once i replaced the wastage with AndyP's loner, checked the distances for the wastegate spring, i used the 1.9bar spring from 034.
First run with all duty cycle to zero, i was getting 0.7bar roughly... hmmm
didnt do anything to the spring, i left it there and started dialing some DC in, and eventually reached my soft spot. Everything looks fine and PID working. I have to say, for the sake of doing runs all night fixing the PID, i went back to my original settings and left it there. Seems as though spool is a bit affected, but i dont mind for now. I dialed in up to 2bar overboost, around 1.8bar till 6000rpm and 1.68 at redline. EGTs were the same as the dyno and here is a comparison to Ross's run.
I took some weight off, as i had -20l of fuel and i have lost some weight as well!!! haha
here is a good representative of today's runs. Fairly repeatable.
i must add that i stumbled upon something very interesting. The incline of the road that the tests are done is very important. and ill show you why....
the run above was done on a slight uphill.
Here is the same run, with a bit more overboost and steady, and slight mid range modifications on the opposite side of the road, ie: downhill..
Huge difference!
so next and final step is to get to the same spot that i used to do the Perfomance box, and connect the perfomance box as well to compare.
Overall, im really happy that now that the wastegate issue is solved, a few more hp can be extracted!
Good to see that it is running well!
That was a large difference on the pulls, must have been a decent incline/decline?
Flat ground is a must, alternatively average the pulls.
One advantage that accelerometer based loggers have is that they actually seem more immune to slight inclines/declines. At least that is my experience when comparing graphs made from logs on both incline/decline. I think the reason is that even though the accelerometer gets tricked by the incline and reads slightly higher, the car accelerates slightly slower, compensating. Pulls should be made on a road that is as flat as possible, though. Exact same test spot (find a road sign or something) is important too, of course.
1995 RS2 on Alcohol (6.8sec 100-200km/h)
1994 80E Avant
1986 2L Golf 2 on Alcohol
Sure.
These runs were only done through vems logs though, not the GPS. So it remains to be seen what it will show on the same road as the previous runs.
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