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Old 04-29-2011, 03:58 AM   #1
ScooByBooSt007
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FP HTA68+Meth 368hp 25psi

Default Problems Hitting target boost levels with grimmspeed MBC...

So about a month ago i got my car Dyno tuned using the grimmspeed EBCS with a Tial 38mm EWG with a 10 psi spring installed. what I loved about the EBCS whs the fact that it produced a rock solid 25 psi all the way to redline with just a 10 psi spring, But what I hated was how it achieved that boost which is why I got rid of it. The EBCS was so slow building boost that it would make full boost nearly towards the end of my powerband. This was a Hugh problem not only cuz it felt like i had no torque but when going into the next gear, I was getting boost spike which in turn would cAuse the EBCS to blow the EWG all the way open and then drop to wastegate duty and I would never again achieve that 25 psi unless I released the throttle and started again. With thAt being said I went ahead and sold it and bought Grimmspeeds newest Manual boost .

The problem I'm having now is I cannot achieve my target boost of 25 psi whatsoever... As a matter of fact, it won't even let me hit 20 psi. It basically monsters up to about 18.5 ,blows open the EWG and falls flat , tapering down to 11 psi at about 6500 rpms. I even adjusted this mbc almost allthe way down and it still only his maybe 19 psi. I'm sure it has to do with the small spring thy I have in the EWG but what's baffeling me is.... How is it I was able to achieve 25 psi with a bleeding style (which is basically a controlled boost leak) boost controller witha 10psi EWG spring but can't even come close to that with a Manual boost controller??? Just dosent make sense to me...
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Old 04-29-2011, 09:09 AM   #2
mostasteless
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I'm not familiar with the Grimmspeed MBC, did it come with more than one spring? My Hallman Pro came with 2 springs, one for lower boost application and another stiffer spring for higher boost. If so try putting in the other spring.
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Old 04-29-2011, 09:41 AM   #3
Unabomber
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You cannot swap out boost control solutions willy nilly and expect identical results. How you are at this power level and haven't learned this yet amazes me. You need a tune. STAT.
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Old 04-29-2011, 09:47 AM   #4
xluben
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Quote:
Originally Posted by Unabomber View Post
You cannot swap out boost control solutions willy nilly and expect identical results. How you are at this power level and haven't learned this yet amazes me. You need a tune. STAT.
Regardless of tune, a properly installed manual boost controller should be able to hit at least the same boost levels as any other system. I agree that you shouldn't just swap out your boost control system without a retune, but your results indicate that something is not installed properly, or not working properly. I would resolve this before the tune, or you are going to be wasting your tuner's time while you try to fix a mechanical issue.
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Old 04-29-2011, 11:03 AM   #5
the suicidal eggroll
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Sounds like there's a mechanical problem like xluben said.
You've checked for boost leaks? You installed the valve seat in the EWG properly correct? What did you use to close off the IWG (assuming you have one)?
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Old 04-29-2011, 12:21 PM   #6
GrimmSpeed
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Hey! I'm sorry you've been having issues. We've successfully tested and ran this MBC from an operating range of 15-60 psi on a bunch of different turbos from our trusted tuners help, all with one spring. One thing you might want to check is if the vacuum lines are routed backwards. Make sure the boost source from the compressor cover is going to the bottom/parallel port on the MBC. Also be sure to check over some of the recommended suggestions above.

Be sure to contact us directly if you need a quick response on anything!

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Old 04-29-2011, 04:06 PM   #7
ScooByBooSt007
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Quote:
Originally Posted by xluben View Post
Regardless of tune, a properly installed manual boost controller should be able to hit at least the same boost levels as any other system. .
this is exactly the same way im thinking..of course i know for sure i need another tune but like you said i should still be able to hit somewhere near my targe boost levels. at first i thought the way i have it installed was an issue. ive got it installed the way that grimmspeed says to install it with the top nipple on the EWG venting to atomsphere. im honestly not use to that style of installation as ive always know boost controller to use both top and bottom ports on the EWG with the top port "T" off from the boost pressure source but thats what they say to do.

i still think it may by my EWG spring but it had no problem making up 15 psi difference with the EBCS.

ill check my plumbing again and see whats going on.
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