MX5 Mazdaspeed turbo question.

RE '04 MX5 Mazdaspeed. Installed a device that claims to "up" the pop off pressure of the stk. turbo. Can't tell if if it improves acceleration. But when running past 4500 rpm in 4th gear,there is a momentary "cough" and then car continues to acelerate. Anyone have any ideas. Car does not do this in lower gears.
 
My guess is the 'device' is a manual boost controller?
 
sounds like a manual boost controller or aftermarket wastegate... except for the part about "only in 4th gear" (and I'm not familiar with the MSM turbo to know if the wastegate is external or internal)

without more data, i'm guessing its some skeezy ebay item that messes with something, and is only noticable in 4th gear because (at least in my non-turbo '99) you rarely go past 4500 rpm in 2nd or 3rd... or blip by it so soon after shifting any roughness would be difficult to notice.
 
R2s99zoom said:
sounds like a manual boost controller or aftermarket wastegate... except for the part about "only in 4th gear" (and I'm not familiar with the MSM turbo to know if the wastegate is external or internal)

without more data, i'm guessing its some skeezy ebay item that messes with something, and is only noticable in 4th gear because (at least in my non-turbo '99) you rarely go past 4500 rpm in 2nd or 3rd... or blip by it so soon after shifting any roughness would be difficult to notice.
I hope not, otherwise he aren't driving it hard enough. Under 4500rpm you're just wasting time :p

The W/G on the MS is internal.

i wish the o/p would give us more details. But until then, lets speculate, shall we? :D that's always the best part in threads like this (alright)
 
Well, if that's true the MSM is known to hit fuel cut around 11psi. I never experienced it until 15psi and sometimes not at all.

Also, he is saying he only experiences it in 4th. I had it in all but 6th and rarely in 5th. HRM, someone needs to come back and explain things better. :(
 
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If it is a mbc you have it is hitting fuel cut. Mine did this all the time due to my aftermarket intake and no cat. If you don't have a boost gauge and have no idea how much the boost has been raised I would suggest removing the mbc before you damage the engine. However, the msm engine seems to holding up quite well to abuse according to people on this forum and the mazdaspeed miata forum.
 
Gaboost said:
If it is a mbc you have it is hitting fuel cut. Mine did this all the time due to my aftermarket intake and no cat. If you don't have a boost gauge and have no idea how much the boost has been raised I would suggest removing the mbc before you damage the engine. However, the msm engine seems to holding up quite well to abuse according to people on this forum and the mazdaspeed miata forum.
roffle @ that forum.

when I was there they were all morons. ;P

Do they still believe that the turbo can't handle 15psi of boost? ALSO, are they all still stuck on hitting fuel cut at 11psi and not believing you don't hit it until 15? Good times on that forum.
 
Yeah, I agree with you on that one. Funny this is the forum I still go to, I haven't been on that one in a while.
 
Gaboost said:
Yeah, I agree with you on that one. Funny this is the forum I still go to, I haven't been on that one in a while.
I still hold my ban on that forum up high. Love it.
 
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