MAP EF2 boost creep troubleshooting
You could remove the cotter pin that secures the turnbuckle onto the wastegate's pivot arm and pry the turnbuckle/actuator rod off the pivot arm. This would essentially leave the flapper valve "free".
With the actuator rod disconnected in this fashion, if boost does not rise above 8-11 PSI then this would mean that the turbine housing's bypass port and the flapper valve do in fact vent enough exhaust to control boost and that the creep is not related to the bypass port in the turbine housing or the flapper valve or the turbine housing itself.
If however, boost creep persists with the actuator rod disconnected then the issue is most likely the bypass port being too restrictive and needing to be ported.
With the actuator rod disconnected in this fashion, if boost does not rise above 8-11 PSI then this would mean that the turbine housing's bypass port and the flapper valve do in fact vent enough exhaust to control boost and that the creep is not related to the bypass port in the turbine housing or the flapper valve or the turbine housing itself.
If however, boost creep persists with the actuator rod disconnected then the issue is most likely the bypass port being too restrictive and needing to be ported.
Last edited by sparky; May 26, 2012 at 09:25 PM.
As a practical matter the OP's issue is complicated by the fact that he has minimal mechanical abilities. It is really hard to troubleshoot these issues if you can't spend time on them yourself, or don't have the mechanical skills. I can sympathize with the OP. It might be extremely expensive to pay a shop to track the source of the problem down as it might involve a lot of trial and error, R&R, tinkering etc.
If I lived in New Jersey I'd swing by and help you out for sure though Buddy....GL
If I lived in New Jersey I'd swing by and help you out for sure though Buddy....GL
Last edited by sparky; May 26, 2012 at 09:25 PM.
As a practical matter the OP's issue is complicated by the fact that he has minimal mechanical abilities. It is really hard to troubleshoot these issues if you can't spend time on them yourself, or don't have the mechanical skills. I can sympathize with the OP. It might be extremely expensive to pay a shop to track the source of the problem down as it might involve a lot of trial and error, R&R, tinkering etc.
If I lived in New Jersey I'd swing by and help you out for sure though Buddy....GL
If I lived in New Jersey I'd swing by and help you out for sure though Buddy....GL
i agree, that will make it all the more difficult to diagnose through an online forum. But that is also the reason i really believe his issue is something a lot more basic.
OP,What parts and pieces were swapped between the point you had no boost creep in your car, to where you did?
Sparky I disagree with disconnecting the actuator. It can easily bypass enough air unhooked to prevent any boots from being created. Once there is significant exhaust volume it can start to take off. Example is a 16g on a DSM. If you run less than 12psi it will usually hold. Go over that and it will creep right to about 20psi. If a stock 10psi actuator is installed and it still creeps there is a problem.
You are probably right batty. I hadnt thought of it that way. I just thought that it would be something simple and relatively easy to try. But, it is true that the rise in gas flow volume through the turbine housing rises exponentially as turbo shaft speeds and engine speeds increase.
I once had a Garrett T04E with a clipped H2 turbine wheel stuffed into a .63 housing on a Buick that would spike instantly(not creep) to 22# with the WGA disconnected from the flapper valve. So, flapper wired full open, no load on the motor, and the tranny in "park" and when you'd mash the throttle the boost gauge would flash to 22#! That sucker spooled!
Finally, we had to dual-gate it by installing a secondary external gate on the crossover pipe in addition to the fully ported internal gate with the extra large diameter, oversized PTE flapper valve. But, that's another story.
I once had a Garrett T04E with a clipped H2 turbine wheel stuffed into a .63 housing on a Buick that would spike instantly(not creep) to 22# with the WGA disconnected from the flapper valve. So, flapper wired full open, no load on the motor, and the tranny in "park" and when you'd mash the throttle the boost gauge would flash to 22#! That sucker spooled!
Finally, we had to dual-gate it by installing a secondary external gate on the crossover pipe in addition to the fully ported internal gate with the extra large diameter, oversized PTE flapper valve. But, that's another story.
Last edited by sparky; May 28, 2012 at 07:14 AM.
Yeah, that car would hit 21 crossing a 2-lane wide intersection from a zero boost, walked-out, roll-on.
But, back to the Op's issue....sorry. I am not at all familiar with the turbine housing casting or the bypass passage of the MAP turbos. The MAP people say that there has never been a creep issue with their housings though.
So, what else could be causing the creep? I'd like to see the WGA directly connected to the boost reference source w/o any fudging from WGDC, solenoids an all that extraneous paraphenalia.
Once base pressure is achieved then incrementally increase spring pressure to see if it will hold steady at target boost level or at what boost level it wants to start to creep when setup in this basic fashion.
But, back to the Op's issue....sorry. I am not at all familiar with the turbine housing casting or the bypass passage of the MAP turbos. The MAP people say that there has never been a creep issue with their housings though.
So, what else could be causing the creep? I'd like to see the WGA directly connected to the boost reference source w/o any fudging from WGDC, solenoids an all that extraneous paraphenalia.
Once base pressure is achieved then incrementally increase spring pressure to see if it will hold steady at target boost level or at what boost level it wants to start to creep when setup in this basic fashion.
Last edited by sparky; May 28, 2012 at 07:41 AM.
Thread Starter
Evolving Member
Joined: Oct 2010
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From: new jersey
Wondering if anyone else noticed that the OP lists his drive as being an Evo X? Shouldn't this thread be over in the X forums? Not trying to be picky but....anyway I hadn't picked up on that detail til now. Now I know why he's mentiong Turbosmart WG's. I'd never heard of those. But, I figured that I was just out of the loop due to my old age. LOL