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Old 10-27-2008, 10:45 PM   #16
TurboSquirrel
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Quote:
Originally Posted by cewrx7r1 View Post
The boost curve is sloppy like your EBC is not functioning too well or not properly hooked up. It spikes and then drops off erraticaly.

Mine did that when I first hooked it up. Then I tried hooking my EBC differently than the manual showed. If you use the turbo outlet as your boost source for both the WG and EBC, then it senses a higher base pressure than the controlled pressure source. This is caused by the pressure drop in the IC.

I take my pressure source from my Greddy TB elbow and that "Ts" into the WG side and WG solenoid input. The IC also acts like a filter to smooth out fluctuations.

This made a great improvement in my boost control. You might also need to experiment with the GAIN to obtain the quickest spoolup that does not either cause spiking or boost start to increase.

You max HP was produced at 15 psi boost. Thus if it stayed at 16psi, you would have made maybe another 15 HP.
"Ray said I was making about 15HP / pound of boost."
Thanks Chuck, your guide has been invaluable to me learning this stuff and helping tune my idle / cruise! I'll see how adjusting the gain helps spoolup.

Quicker spoolup is my main goal.

I'm using an old Profec-B with the solenoid pressure sourced from the UIM. The "OUT" side of the EBC solenoid goes to the top of the WG, and the side of the WG is being sourced near the Compressor before the intercooler.

Previously, I had the side of the WG pressure source coming from the UIM and I would get boost creep consistently. Have not seen any creep since sourcing from the compressor.

Thanks

- Kevin






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Old 10-27-2008, 10:46 PM   #17
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I spoke to another owner of this kit and he is claiming actually slightly worse response in 3rd and 4th gear but marginally better response in 1st and 2nd? His car made around the same power at the same boost level, within about 10rwhp.

I havent seen many if any other dyno graphs or reports about this turbo. At this point I am lost on what is causing the slow response. Hopefully adjusting the Profec B will help dramatically. We will see I guess.

Kevin, I know the wastegate spring is 13lbs, when you had it running directly off the spring bypassing the Profec was response really any better or have you tried this since have it tuned?
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Old 10-27-2008, 11:41 PM   #18
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Quote:
Originally Posted by TurboSquirrel View Post
Thanks Chuck, your guide has been invaluable to me learning this stuff and helping tune my idle / cruise! I'll see how adjusting the gain helps spoolup.

Quicker spoolup is my main goal.

I'm using an old Profec-B with the solenoid pressure sourced from the UIM. The "OUT" side of the EBC solenoid goes to the top of the WG, and the side of the WG is being sourced near the Compressor before the intercooler.

Previously, I had the side of the WG pressure source coming from the UIM and I would get boost creep consistently. Have not seen any creep since sourcing from the compressor.

Thanks

- Kevin
get rid of the pressure source from the intake manifold. run pressure from the compressor housing to the "in" on the profec and run the "out" to the side port on the wastegate and leave the other port open(could be the other way around for the the wastegate, i cant ever remember)that could be part of your problem, but damn, that is absolutely horrible for response. when i had my regular 35r on a stock port engine with the 1.06 housing i was seeing 18 psi by~3800. the 500r just has a differend comp wheel if im not mistaken. that just seems really odd, especially for a ported motor.

have you checked all your intercooler piping for leaks? intake gaskets?

:edit: just read the above post copied from the other forum. the sp has a different hotside, but is getting better response than the standard 500r according to sean. so you should be hitting 15psi under 4k no problem.
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Old 10-28-2008, 12:06 AM   #19
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Quote:
Originally Posted by cewrx7r1 View Post
The boost curve is sloppy like your EBC is not functioning too well or not properly hooked up. It spikes and then drops off erraticaly.

."
It is hard to see in the graph that Kevin posted but the boost actually only fluctuates less than 1psi between 5100-7500 rpms. Only flucuated about .5psi from 5500-7500rpms.
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Old 10-28-2008, 12:12 AM   #20
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Quote:
Originally Posted by dregg100 View Post
get rid of the pressure source from the intake manifold. run pressure from the compressor housing to the "in" on the profec and run the "out" to the side port on the wastegate and leave the other port open(could be the other way around for the the wastegate, i cant ever remember)that could be part of your problem
dregg100 I had the EBC hooked up that way once before (inline between the pressure source and the side of the WG with top open to atm) and it would never allow the WG to open (as if the WG was never seeing pressure). DIP switches set to external WG option btw.

Just to be clear, here's how I have it setup currently:

- a line from Compressor to the side of the WG
- a line from the (OUT) port on the solenoid to the top of the WG
- a line from the UIM to the (IN) port on the solenoid
- a line from the UIM to the Profec-B control box inside the car

New UIM to LIM and TB Gaskets. No boost leaks that I can find between compressor and TB.

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Old 10-28-2008, 08:47 AM   #21
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have you tried changing the dip switches to the "other" settings that greddy says to do if you are having problems? its on there website.
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Old 10-28-2008, 11:46 AM   #22
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Thanks for everyone's suggestions so far!

After doing some logging this morning, here are my results after adjusting the GAIN setting on the EBC. Also, David suggested seeing how it did running off the WG only and I have included that result as well.

There are three charts attached. The vertical line is the point where my expected max boost was obtained.

Each run is in 3rd Gear from around 3000rpm

(1) Chart_WGonly.JPG: EBC off (.9 BAR Spring)
(2) Chart_EBC_HighGain.JPG: EBC on, and the GAIN setting high (overboosted)
(3) Chart_EBC_Current.JPG: EBC on, and GAIN adjusted to desired boost

After adjusting the GAIN settings, the best spoolup achieved was around 5300rpm. Running on the WG only did not appear to improve spoolup.
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File Type: jpg Chart_WGonly.JPG (113.2 KB, 39 views)
File Type: jpg Chart_EBC_HighGain.JPG (132.6 KB, 29 views)
File Type: jpg Chart_EBC_Current.JPG (126.2 KB, 28 views)
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Old 10-28-2008, 12:29 PM   #23
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Wow, that is pretty poor response from an 0.84 A/R housing. I would expect 15 psi closer to 4k RPM.

Your setup seems correct to me. Someone already mentioned it, but check to make sure you have the correct settings on your dip switches.

I would also expect better response off the wastegate alone, meaning that your EBC setup might not be a factor. Are you sure that you don't have any exhaust leaks on either side of the manifold? I had a friend with a similar situation and once he fixed his exhaust leak he was spooling 500+ RPM earlier than before. It was tricky too because you couldn't hear it at idle or cruise. It was really only leaking under boost and he had an open wastegate so there was no way to verify the leak until it started leaving carbon deposits under the manifold.
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Old 10-28-2008, 03:22 PM   #24
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Im pretty sure Kevin doesnt have any leaks between the engine/manifold, wastegate/manifold, or turbo/manifold.

His response in 3rd gear is actually better than the only other person who has given me info about this kit. Its not impossible that there is a leak but everything on this car is brand new.
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Old 11-05-2008, 10:36 PM   #25
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Did you guys make sure the flanges on the manifold were flat?

Jack
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Old 11-05-2008, 11:48 PM   #26
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Default a-spec

I just dont think it could be the A-spec mani as thats the same mani I run but on a larger turbo (4094). I was seeing full boost around 4750 on my past setup (BDC streetport/ 3 inch exhaust).
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Old 11-06-2008, 07:56 AM   #27
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I dont think it is the manifold either. It appears it was my fault Kevin or myself will update this thread in a few days when I get a chance to work on his car. I have a feeling the spoolup will be much better.

I wont leave you guys hanging, we had some fitment issues with the wastegate hitting the subframe with the kit. So I had to remove the wastegate from the manifold to drop the engine back in the car(we removed the engine to reseal the oil pan). I dont remember installing the valve seat that comes with the Tial BOV. We had to put on and take the wastegate off several times and it appears I never installed the valve seat that helps seal up the wastegate/manifold v-band connection. I will reinstall it in a couple days(hopefully have time) and we will report back. Kevin got his hands on about 5 other 500r dyno charts and they were all seeing 14-16lbs at about 43-4400 which is about 1k rpms sooner than Kevin.
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Old 11-06-2008, 11:49 AM   #28
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Hmmm...exhaust leak....
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File Type: jpg DSC01189.JPG (113.5 KB, 41 views)
File Type: jpg DSC01170.JPG (110.7 KB, 44 views)
File Type: jpg DSC01178.JPG (90.6 KB, 35 views)
File Type: jpg IMG_0306.jpg (108.7 KB, 33 views)

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Old 11-06-2008, 03:20 PM   #29
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That would explain a few things. Oh, by the way David, my turbo is a 68mm turbine vs. turbosquirrels 74mm turbine. An A to B comparison may occur some later next year once I get my car back on the road.
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Old 11-06-2008, 03:25 PM   #30
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Talking WG Valve Seat Installed - Problem solved!

Alright, problem is all sorted out now!

I've attached PFC Charts showing 3rd and 4th Gear runs from around 3K RPM.

Much better response than before with out the valve seat installed.

Happy Days!
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File Type: jpg WG_Valve_Seat.jpg (105.6 KB, 34 views)
File Type: jpg Chart_3rdGear_Fixed.jpg (130.1 KB, 55 views)
File Type: jpg Chart_4thGear_Fixed.jpg (136.6 KB, 45 views)
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