zmedic16

iTrader: (6)

ok here we go. i searched about this issue in these forums and wasnt able to come up with anything related to the issue. i Have an 06-revup mt with a turbonetics kit modified to fit.(dinging in the up pipe to go around the steering lines maybe a 1/4inch or so give or take). i went for tuning to MRC and initialy Julian hit a little bump on the road due to the Open Dumps throwing off the Airfuel mixture a bit. As the tuning continued julian discovered what is called a "boost creep" after 5k rpms creeping up to about 8-8.5psi. Julian set up my utec to bogg if it ever goes over to or higher than 9psi. LINK TO ORIGINAL THREAD https://my350z.com/forum/showthread....cs+boost+creep.

my list of mods are as follows.
mrev2-
plenum spacer
ur pullies
turbonetics turbo w/waterlines
38-40mm tial wastegate with open dumps
.5bar spring 7.2psi
custom 3.5" exhaust with a 4"muffler exit.

if julian would like to add the dynos with the psi here would be great.

taurran

iTrader: (18)

I'm not sure why you'd even need an exhaust that huge, but it may be the source.

The next question would be if you're using the revised wastegate piping. I can see you're using a tial wastegate so everyone can't blame it on the turbonetics wastegate, I guess.

The injectors you have are fine for those power levels, as the kit was built to run 8.5psi out of the box. I can't see your AFR graph but if you're within safe levels there is no need to worry.

zmedic16

iTrader: (6)

unfortunatly i dont have the updated piping. i have the original piping with open dumps. im not having a boost spike issue its just the creep. a resolution i have recently looked over from the evo and srt4 forums some of them port the inlet and outlet of the wastegate and some go as far as getting a bigger wastegate all together. i wish julian would chime in with the issues he was having while tuning the car as well.

Taurran thanks for the reply.

zmedic16

iTrader: (6)

i guess no one other than taurran has an opinion.

Audible Mayhem

iTrader: (48)

yeah , the old setup sucks. we have cars tht make like 6 psi then just boost creep all the way to 10. there is nothing to do except to get rid of that old setup.

you can weld on a wastegate into another place, that will work. or replace the whole uppipe.

Ahsmo

iTrader: (13)

For my own and perhaps others eduction, why do you think that?

zmedic16

iTrader: (6)

re-weld the wastegate where on the uppipe???? this would be great news. im thinking of upgrading the wastegate to a 44mm, or stick it out until i can get the SFR hotside upgrade kit.

taurran

iTrader: (18)

I don't think. I know.

He's not flowing enough to justify a 3.5" exhaust at those power levels.

If you look back at the reason why the original kit had boost creep issues, then you'd understand why.

zmedic16

iTrader: (6)

ok here we go. hopefully we not getting this mistaken as a "boost spike" but more of a boost creep. my open dumps begin to open at around 5.6-6psi and fully open at around 7psi. the creep begins a little after 5500rpms at wich it increases to nearly 8.5psi at redlin, sort of "supercharger tendency" according to julian. this is neither a blessin or a curse due to the fact that my car makes power all the way till redline instead of falling off like most of the turbonetics kits. my torqueline stays flat at around 360-370wtq and hp steadily increases to about 410whp at redline. julian set up a safety trigger to bogg the car down if it goes over to 9psi. my mayor concern is how unpredictable its going to be with weather changes. as for concern on the motor im not extremely worried due to the fact that the "boost creep" manifests itself on the right place wich is at higher rpms and not affecting my torque whatso ever. This is my amatuer opinion as i am a begginer in f.i.

feel free to opiniate on my research and findings.

taurran

iTrader: (18)

Yep. The old "overboosting" issue was exactly as you described, as boost creep.

Do you have a boost controller installed? One option may be to install an HKS EVC6. Having that installed would not only help regulate boost to a steady level, but would also keep the boost levels steady when intake temps fluctuate.

zmedic16

iTrader: (6)

Taurran thanks for your quick reply.
So you think that the evc6 would regulate the boost and as well as the boost creep?? this might be a solution that i can work with. im not familiar with the hks evc6 would anyone care to elaborate on how this will regulate my boost issue? does it have multiple excess boost release ports??

taurran

iTrader: (18)

It electronically controls the wastegate, and on auto mode it will quickly adjust wastegate load to account for variations in manifold/compressor boost level.

In theory, it will sense that it has gone past the set boost level and will send a signal to open the wastegate more to lower boost. If you have it running off manifold pressure, it will also open the wastegate to account for temp/pressure drop accross the intercooler piping.

The EVC6 seems to be particularly good at making adjustments in auto mode, so I'd recommend it above others.

zmedic16

iTrader: (6)

sounds very interesting as well as sophisticated. im planning on a build for this winter keeping the tn kit and just add nitrous. i am a fan of single turbos and the overall feeling of it. ok so this will be installed at the end of the month if this will resolve my issue. im planning to boosting to 8.5psi no more no less.

taurran

iTrader: (18)

I'm not absolutely guaranteeing your problem will be totally fixed by it. However, if you do a build you will need one sooner or later anyway. It definitely won't hurt.

Next step after that would be to relocate the wastegate like Jeremy said.