fuel cut, spark blowout, boost leak, IDK?!?

[fbodyfreak]

Ok i just recently picked up 98 GSX. low miles (57k), mostly stock.
When i floor it the car seems to hic-up a little (pull.. pull.. pull.. hiccup, pull.. hiccup). But if i SLOWLY lay into it, there not cutting out really (unless i lay into it too quickly).

Only mods are:
Hallman pro MBC (amount of boost is UNKNOWN ,but i did rotate the controller counterclockwise in an attemp to lower the boost, but still cuts out..)
3" full exhaust.
Stock (new) T25

My uneducated guesses were, fuel cut, spark blowout, or maybe boost cut (from a leak or something). any help is appreciated!
any suggestions?

 

[1davho]

Back the mbc out all the way or bypass it so you are running wastegate pressure. If that doesn't fix it, I would do a boost leak test. And run some Ngk br6es spark plugs gapped to .028.

 

[bastarddsm]

Back the mbc out all the way or bypass it so you are running wastegate pressure. If that doesn't fix it, I would do a boost leak test. And run some Ngk br6es spark plugs gapped to .028.

No. No reason for BR6ES plugs at his level. Run the stock BPR6ES. Gap em at about .025" put new wires on it, if they look crappy. By pass the boost controller till you get a feel for what's going on, or you will blow you car up. Do a boost leak test.

 

[90tsiawdturbo]

Definitely remove the MBC! No one should install a MBC without a aftermarket boost gauge in the first place.....I would do a boost leak test as well

 

[lasershark]

just scoped out your profile like the fbody being a fbody owner myself I gotta say nice! but I would guess with the dsm being that you have a t-25 I think it's maximum efficiency is between 14-16psi and you shouldn't hit fuel cut with that but definitely do a boost leak test you can make a kit pretty cheap