boost creep or something else?
10-17-10, 07:37 AM
#51
"Elusive, not deceptive!”
I use the same HKS divided manifold but I think my wastegate is a 50mm.
I ported the wastegate's housing lightly to unshroud the valve opening area.
No boost creep so far but I am a low booster (12-16psi).
Barry
I ported the wastegate's housing lightly to unshroud the valve opening area.
No boost creep so far but I am a low booster (12-16psi).
Barry
10-17-10, 01:34 PM
#53
"Elusive, not deceptive!”
10-17-10, 02:23 PM
#54
just measured the valve. and i got bout 50 mm. not sure what spring is inside though. i hope this one works!!
looks like this one
http://cgi.ebay.com/ebaymotors/HKS-5...#ht_500wt_1182
looks like this one
http://cgi.ebay.com/ebaymotors/HKS-5...#ht_500wt_1182
11-12-10, 05:27 PM
#56
so i finally got around to installing the 50mm gate. got a new hks yellow spring in it and it STILL freaking creeps!
was getting bout 17 psi now round redline, straight boost source from turbo compressor. idk wat to do now :/
only thing i reused were the vac nipples for older gate to newer one. have a 46mm pipe going to the gate now. as oppose to the 38mm on tial
new on left old on right
was getting bout 17 psi now round redline, straight boost source from turbo compressor. idk wat to do now :/
only thing i reused were the vac nipples for older gate to newer one. have a 46mm pipe going to the gate now. as oppose to the 38mm on tial
new on left old on right
11-13-10, 05:13 AM
#57
BRAAAAAP pssh BRAAAAAP
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geez i couldnt imagine almost two months and a dozen or more times trying different things and still cant figure the issue out...
good luck i know it is irritating
good luck i know it is irritating
11-13-10, 07:52 AM
#58
The hks yellow is rated at 14.2 psi I believe, is your boost stabilizing around there for a significant portion of the rpm band?
A couple other things worth asking at this point (they are all pretty basic, but who knows)
1. Have you pressure tested the boost made at the compressor housing vs the boost made at the UIM? Maybe there is a leak at the compressor source, or maybe the nipple is at a poor tap point on the compressor.
2. Where are you measuring the boost from when you get the 17 psi?
3. I'm assuming that you pressure tested the new gate - if not definitely do so.
If all that passes, you need to add some restriction in your exhaust path. Big ports and larger exhaust housings typically create insolvable creep... So a couple options are:
1. Try a smaller hot side housing on the turbo
2. Add a more restrictive cutback
3. Plug the WG back into the DP
I know how annoying creep can be, I didn't enjoy my car the first year I owned it due to creep... so I feel your pain
A couple other things worth asking at this point (they are all pretty basic, but who knows)
1. Have you pressure tested the boost made at the compressor housing vs the boost made at the UIM? Maybe there is a leak at the compressor source, or maybe the nipple is at a poor tap point on the compressor.
2. Where are you measuring the boost from when you get the 17 psi?
3. I'm assuming that you pressure tested the new gate - if not definitely do so.
If all that passes, you need to add some restriction in your exhaust path. Big ports and larger exhaust housings typically create insolvable creep... So a couple options are:
1. Try a smaller hot side housing on the turbo
2. Add a more restrictive cutback
3. Plug the WG back into the DP
I know how annoying creep can be, I didn't enjoy my car the first year I owned it due to creep... so I feel your pain
11-13-10, 02:45 PM
#60
To test the compressor nipple, I would connect a T-fitting to the WG and add another boost gauge in the car. You should see that gauge read two to three psi higher than the UIM gauge due to pressure loss at the intercooler.
11-15-10, 06:35 PM
#62
pulls were in 34d n 4th gear. i have the hose running straight to the side of wastegate. no vac nipples on the top of gate, both holes are open on top.
this is the spring i got brand new
1405-RA035
http://hksusa.com/products/?id=767
this is the spring i got brand new
1405-RA035
http://hksusa.com/products/?id=767
11-17-10, 06:22 PM
#63
ok got a hand pump dat has its own gauge.
put in yellow spring it seems to open round 20 psi roughly
threw in a green spring it had in it before (never used it) seem to open round 1 ba
wat i did notice is as im pumping i seem to be getting alot of leaking around the valve area before valve comes up.
http://www.youtube.com/watch?v=fYNC4v2GlAw
valve seems to be smooth going up or down
http://www.youtube.com/watch?v=yanqk7we1jw
now i think my problem on my older gate was creep, it held spring pressure on the tial 46mm till 6,000 rmps AND THEN creeped. with this hks 50mm it doesnt seem to hold a steady pressure just kinda rises progressively, like if the spring was a 20 psi spring or something. and if u look at log right above it seems to kinda wanna steady out around 18-20 psi but the spring is SUPPOSE to be a 10 psi spring according to hks. so it doesnt seem like its creeping now but i wonder if that leak im hearing thru the valve isnt allowing diaphragm to read the right pressure and is taking longer to read the actual 10 psi it needs to crack the valve open. make any sense?
put in yellow spring it seems to open round 20 psi roughly
threw in a green spring it had in it before (never used it) seem to open round 1 ba
wat i did notice is as im pumping i seem to be getting alot of leaking around the valve area before valve comes up.
http://www.youtube.com/watch?v=fYNC4v2GlAw
valve seems to be smooth going up or down
http://www.youtube.com/watch?v=yanqk7we1jw
now i think my problem on my older gate was creep, it held spring pressure on the tial 46mm till 6,000 rmps AND THEN creeped. with this hks 50mm it doesnt seem to hold a steady pressure just kinda rises progressively, like if the spring was a 20 psi spring or something. and if u look at log right above it seems to kinda wanna steady out around 18-20 psi but the spring is SUPPOSE to be a 10 psi spring according to hks. so it doesnt seem like its creeping now but i wonder if that leak im hearing thru the valve isnt allowing diaphragm to read the right pressure and is taking longer to read the actual 10 psi it needs to crack the valve open. make any sense?
11-17-10, 07:07 PM
#64
You should be able to apply enough pressure to bring the valve all the way up, then it will settle as air leaks out from the valve shaft. The video is low quality, but it looks ok. Connect the pump to the top port and verify that it holds pressure perfectly, that will verify the diaphragm is good.
Rated spring pressures are not all that accurate and vary car to car. Exhaust back pressure pushing on the valve face will vary car to car making it difficult to predict what boost pressure the spring will open at. I don't remember the numbers exactly, but I think my gate opened at around 7 or 8 psi on my car, but around 14 psi with a bike pump due to back pressure.
That being said, if the gate is working fine, I would definitely try the green spring. You should hear it open around 7 - 10 psi and hopefully should be light enough to control your boost. A 50mm gate should be enough for most set-ups.
Rated spring pressures are not all that accurate and vary car to car. Exhaust back pressure pushing on the valve face will vary car to car making it difficult to predict what boost pressure the spring will open at. I don't remember the numbers exactly, but I think my gate opened at around 7 or 8 psi on my car, but around 14 psi with a bike pump due to back pressure.
That being said, if the gate is working fine, I would definitely try the green spring. You should hear it open around 7 - 10 psi and hopefully should be light enough to control your boost. A 50mm gate should be enough for most set-ups.
11-17-10, 07:21 PM
#65
ya took them with my phone but there is a 720p hd option maybe it will help. i will try the top port tomorrow since i left the other fitting at home.
i took a look at diaphragm and i saw no tears in it.
so the air leaking thru the shaft is normal?
i took a look at diaphragm and i saw no tears in it.
so the air leaking thru the shaft is normal?
11-18-10, 06:13 PM
#72
Otherwise, what psi holds the gate fully open? If the gate is only leaking out the valve shaft and the gate is held fully open at a constant pressure less than 15 psi, then I would assume it's ok to try on the car with the 10lb spring.
11-18-10, 08:20 PM
#73
A 10 PSI tial spring in tial and a 10 psi hks spring in the hks gate.
i didnt really see a oring in the hks. i feel the air escaping right where the valve slides , like the valve guide.
im gonna try the gate with the green spring and post results, hopefully they will be good. if it can hold at least 15 psi ill be happy.
i didnt really see a oring in the hks. i feel the air escaping right where the valve slides , like the valve guide.
im gonna try the gate with the green spring and post results, hopefully they will be good. if it can hold at least 15 psi ill be happy.
08-10-11, 06:54 PM
#74
just to update situation i ended up rebuilding motor again. hose for the wastegate pressure source came off of turbo and it over boosted and motor pinged. i ended up cracking front iron.
i ended up going with a new JGS 50 v band wg like moehler suggested. i left the spring that was in there and did some porting on exhaust manifold outlet and one of the wg runners. running braided hose and -4 fittings now.
tried 3rd gear and it held 5 psi till redline, this wg sounds liek a beast! i can hear it start to open at "0" psi. i may throw in the harder spring that came in the box. but so far so good, seems like this gate fixed my problems!
i ended up going with a new JGS 50 v band wg like moehler suggested. i left the spring that was in there and did some porting on exhaust manifold outlet and one of the wg runners. running braided hose and -4 fittings now.
tried 3rd gear and it held 5 psi till redline, this wg sounds liek a beast! i can hear it start to open at "0" psi. i may throw in the harder spring that came in the box. but so far so good, seems like this gate fixed my problems!
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