Experiencing boost creep with Buschur MBC

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Mar 1, 2009 | 03:59 PM

#31

sparky

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From: Mesoamerica/ SF Bay Area

Most likely you're right. He said that his MBC is turned down all the way too. I still think that he should get a tune and run the 24 PSI and not worry about removing and grinding. A IX should be fine at 24# if properly mapped. I am running my VIII at 23# without a tune. And a IX is good for a couple of PSI more than an VIII. Just get an Email flash.

Mar 1, 2009 | 04:08 PM

#32

Boltz.

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From: St. Charles, IL

Quote:

Originally Posted by sparky

I tried searching what the ideal finished size of the merge hole should be. I didn't find the thread I was lookig for however. I did tell you roughly golfball sized, but I think that some guys grind it out to a larger diameter.

Regulation golfball diameter is slightly less than 1.7". When I said, golfball sized, I really meant that a golfball should fit inside it freely at its shortest radius.

1.5" should be all you need. Thats 38mm. Think about all the big turbos that run the tial 38mm gate. I've run a 57lb turbo at 15psi through a 38mm wastegate. A 1.5" hole should be large enough to keep a ~41lb turbo to 21psi.

P.S- I just installed an ebayO2 in my car yesterday

Mar 1, 2009 | 04:34 PM

#33

sparky

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Quote:

Originally Posted by Boltz.

1.5" should be all you need. Thats 38mm. Think about all the big turbos that run the tial 38mm gate. I've run a 57lb turbo at 15psi through a 38mm wastegate. A 1.5" hole should be large enough to keep a ~41lb turbo to 21psi.P.S- I just installed an ebayO2 in my car yesterday

Yeah, my SSAC has been fine without any porting. 2.5" does seem like way much. So you are probably correct on the 1.5" diameter. I think that the guy who said 2.5" in the thread that I refered to must have meant 1.5", and not 2.5".

I personally prefer to port the wastegate bypass port in the turbine housing as, at least in my mind, it is a more immediate bottleneck and cause of exhaust backpressure.

Last edited by sparky; Mar 1, 2009 at 04:37 PM.

Mar 1, 2009 | 06:09 PM

#34

huevosrancheros

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From: The Stream Of Carol , IL

I have ported my helix o2 housing, I used a nice air compressed grinder(actually my buddies at work did it for me, I supervised) I'll probably put it up for sale though, I am not sure yet. Its staring at me currently right now , beggin to be put in. After personally seeing how they act during a cold winter I am not too sure.

I really want to get an external dump though. I love the noise it makes at WOT. Not too mention that supposedly you won't get boost creep(??? who knows).

Just to let you guys know that a helix o2 housing can accomadate a golf ball thru the merge hole perfectly fine. In fact the one we installed on my buddies evo (turbodemon) was one of the o2 housings that passed the golf ball test. That leaves me to belive that it is more temp related than the size of the merge hole.

Keep in mind that here in the chicago land area we have seen some really bitter *** cold this winter .

I am talking in circles now... My eyes just got crossed.