EBC up all the way and still only 20psi??

[suprafanatic]

I have just installed a 67mm Billet turbo, and a 50mm wastegate. Today i went and put 110 octane gas in the car so i could turn up the boost and tune it for a high boost setting. I have a Greddy Profec B electronic boost controller. So in the procces of turning up the boost and tuning i found out i cant run over 19-20psi.. I had the EBC turned up all the way and still wouldnt boost any higher than that. I thought the Profec B was good for 30psi or so?? could it be a boost leak somewhere not letting me boost any higher? On my last turbo with the Profec B I know it would let me boost well over 20psi if i turned it up.

 

[suprahero]

Did you adjust the gain up? If you don't turn the gain up, it won't boost but so high. What are your setting set at right now? I have the AVC-R, but I'm pretty sure it's the same principal. You have a duty cycle and a gain if I'm not mistaken.

 

[suprafanatic]

It has a balance, for mild or sharp. same concept as the gain i believe. But yes that is up all the way to where it would run max boost. and still only 20psi

 

[suprahero]

I would definately do a boost leak test to make sure you don't have one. Your turbo should spool way higher than that, and I've always heard good things about your boost controller.

 

[suprafanatic]

haha, This turbo should deff spool alot more than that, theres evo's pushing 50+psi threw them. And I know the EBC will boost higher cause I have boosted over 20psi with it before. Going to do a boost leak test tomorow, I'v never done one so im curious to see what we find. Also.. off topic but how often should the fuel filter be changed? I was looking at mine and im pretty sure its the original fuel filter...

 

[funky_monkey58]

I am willing to bet that you are getting excessive back pressure on your wastegate and it is blowing open.

You will need to add a boost reference to the end of your wastegate, so when you boost it helps hold the valve closed.

I will try to find a diagram to help you, if not I can just make one.

 

[suprafanatic]

That would be great.. i did notice there is a 3rd smaller port on the top of the wastegate.. would that be for another boost pressure inlet?? When i run it just on the wastegate it only hits like 7 PSI. so it doesnt have a very strong spring..

 

[funky_monkey58]

That would be great.. i did notice there is a 3rd smaller port on the top of the wastegate.. would that be for another boost pressure inlet?? When i run it just on the wastegate it only hits like 7 PSI. so it doesnt have a very strong spring..

That is exactly what it is for, I ran into the same exact problem... Just this last saturday actually.
Once I redid the setup I was able to dial it in and at one point I hit 30.98 psi:aigo:.

I will now look for a diagram for you.

Ninja edit.

 

[Poodles]

Boost control is going to be unreliable over 2x the spring pressure...

 

[IJ.]

Boost control is going to be unreliable over 2x the spring pressure...

I've ran 30psi on a 5psi spring no problems at all.

 

[Poodles]

Always been told the pressure will push the wastegate open.

 

[IJ.]

That's why you put boost pressure into the back of the diaphragm to keep it closed.

5psi spring + 25psi boost = 30psi gate opening.

It's NOT a flapper style gate like stock.

 

[Alec]

I think I know your problem. First off, don't turn the balance all the way, keep it more towards the middle. Adjust the balance so that the boost will hold to redline but won't spike. Too soft and the boost will drop off towards redline, too firm and you will get boost creep. Are you doing the adjustment on low boost mode or high boost mode? Try setting it on high boost mode, you have a little more control as opposed to low boost.

 

[suprafanatic]

I stated that i had the boost controller set to its max setting.. that should indicate that i have it on the high boost setting So IJ what would you suggest the problem is? maybe a boost leak going to the top of the wastegate? If its not seeing enough boost it may be the cause to why its opening to early?

 

[IJ.]

I'd go back to basics, plug the WG into the boost source using only the side port and see how it behaves on just the spring, then I'd verify the ports on the boost control solenoid and replumb.

I'd then make 100% sure of the dipswitch settings on the unit as mentioned in the other thread.

IF the WG is plumbed correctly it should control the boost right up to the point that it blows the crank out of the engine