boost drop off????
Assuming you're using an MBC or straight up wg can - a helper spring can resolve some of that. It helps to make it adjustable (threaded rod) so you can make changes to the spring tension.
Joined: Sep 2005
Posts: 34,382
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From: Chicago. (The less-murder part.)
I've recently been fighting this same battle myself, in the quest for a nice, consistant 14 PSI or so. With the MBC alone, my setup typically will spike to 15 and then settle down to maybe 11 or 12. Ridiculous.
I've done a preliminary helper spring setup, but all I seem to have accomplished thus far is to move the spike upwards a bit.
I used what I felt was a moderatly sized spring, not wanting to go too tight right outta the gate. I can't really say that it helped much- I'm still spiking... Base boost (with the MBC bypassed) went from about 5.5 PSI to 9 PSI. Relatively speaking, are others using stronger springs than this?
I've done a preliminary helper spring setup, but all I seem to have accomplished thus far is to move the spike upwards a bit.
I used what I felt was a moderatly sized spring, not wanting to go too tight right outta the gate. I can't really say that it helped much- I'm still spiking... Base boost (with the MBC bypassed) went from about 5.5 PSI to 9 PSI. Relatively speaking, are others using stronger springs than this?
I haven't gotten anything close to flat. I was seeing ~2psi fall after peak boost. The helper spring reduced that to just over 1psi. 
dotted line = boost

dotted line = boost
I joined while back helping my buddy with his 91 turbo. I sold my evo 9 went with a gsxr 600 now im rocking my turbo miata.. And how can you hook up the mbc feed to the coldside of the intercooler? Just drill and tap for a 1/8npt barb in the piping after the intercoolerm before the TB.. I did it a while back and got another 1.5psi till redline..
Idk why you guys just gotta hack on someone just cuz they havent posted yet. Im not a newb. Lol ive been boostin for 5 years.. And tuning evos for the past 3.. Lets keep on topic from now on
Idk why you guys just gotta hack on someone just cuz they havent posted yet. Im not a newb. Lol ive been boostin for 5 years.. And tuning evos for the past 3.. Lets keep on topic from now on
I joined while back helping my buddy with his 91 turbo. I sold my evo 9 went with a gsxr 600 now im rocking my turbo miata.. And how can you hook up the mbc feed to the coldside of the intercooler? Just drill and tap for a 1/8npt barb in the piping after the intercoolerm before the TB.. I did it a while back and got another 1.5psi till redline..
Idk why you guys just gotta hack on someone just cuz they havent posted yet. Im not a newb. Lol ive been boostin for 5 years.. And tuning evos for the past 3.. Lets keep on topic from now on
Idk why you guys just gotta hack on someone just cuz they havent posted yet. Im not a newb. Lol ive been boostin for 5 years.. And tuning evos for the past 3.. Lets keep on topic from now on








