Boost Creep

[fat_85_civic]

Im having a little trouble with holding boost in my car.

The set up is:

DOHC ZC
GT2560R
Log Manifold
2.5" exhaust

plus more but i think this is the most important.

The problem is once full boost hits at around 4000ish it will creep up and extra 2psi by red line.

The same thing has happened on boost settings of 9, 6 and 4psi each time only increasing by 2psi.

At first when it peaked at 11 i swapped the wastegate actuator over to a lower psi adjustable garret one for the next two settings.

Im hoping to have it tuned gain very soon and wanted to fix this problem before then.

Any ideas are appreciated guys!

Thanks
Luke

[mugen_ctr]

faulty boost controller? is it manual bleed valve or ebc? although it could be numerous things....

[fat_85_civic]

no boost controller as yet, just running the the actuator straight off the IM. Im going to get that changed to the compressor cover when i get around to installing my EBC. Here's a graph of what the boost does if it helps.

[Lukezen27]

e-Boost2

Can't beat it and gives you a completely flat boost line

[DLO01]

Internal wastegate? Any photos of your setup?
As long as it tunned. Don't see a problem.

[fat_85_civic]

Yep internal gate. Im planning on having my computer run a Haltec electronic solenoid so i guess ill get that all set up then take her in to be tuned.

Heres some old pics of the set up as i was first putting it on:





and the link to the whole build http://www.ozhonda.com/forum/showthr...rbod-AH-Hatch!

Luke

[Limbo]

usually you can tune it to hold boost at a certain level. I'm sure it will get sorted on tune

[DLO01]

The fact that its creeping 2 psi at each of your individual boost settings, to me, suggests that its a function of the actuator. If it was creeping due to maxing out the flow through the wastegate, you 'would' see more creep at the 4psi setting due to more exhaust flow having to flow through the wastegate bypassing the turbo to hold the lower psi setting.

Do what you wish with boost controllers, but as long as the tuner takes in account the 2psi creep, then theres no issue.

[fat_85_civic]

heres two thoughts ive just had while thinking about this.

1) I had to clock the turbo and use a different bracket to hold the actuator, could the actuator not be pussing far enough to open the wastegate fully?

I guess to test this i would have to pressurise the wastegate and watch to ensure it is fully opening.

2) The wastegate hole cant be too small if it is only boosting 6 now but has also held 11 with a different actuator right? Because when it was creeping at first to 11 i was worried that was the case, but that would mean 11 is the minimum boost i would be able to run i think? Unless im missing someting

Cheers
Luke

[mugen_ctr]

have u tried adjusting it via the rod?

I think first off try running a manual bleed valve, and seeing if the boost holds nicely, there cheap as dirt an the ebay version work as as good as the turbosmart bleed valves that cost triple amount