Fireindc

iTrader: (13)

Hey i know its the miata form, but im the only one out of my friends who knows anything about turbo setups (sad, i know) and i really cannot figure it out.

Its a honda B18b integra with a diy turbo setup on it, it has a t3/t4 turbo setup with a turbonetics delta external wastegate. It has a greddy type-s bov, and a badass FMIC. The piping seems to be completely cherry.

Well as of last night it was boosting strong, about as strong as me on 8psi of boost. His wastegate is set at 7psi. No problems.

It was boosting super hard at about 3krpms for a good 5 pulls, he decided not to boost it anymore as we go through town, we ate at sonic, then on the way home he punched it and nothing really happend.

The car now makes a spooling noise, and a long pshhhhhhhhhhhh but no boost built at all, and no increase in power. It is not the bov, weve completely ruled it out, we are leaning towards the wastegate...

Also as of today, i was under the car and i noticed oil leaking out through the downpipe where it connects to the turbo, this struck me as very odd.

Again, i know this is MIATAturbo.net, but i really trust most of you guys since youve all helped me out so much.

Thanks a ton, Nate.

PAT!

iTrader: (1)

Check the shaftplay on the turbo.
Pressurize the piping for leaks.
Check the diaphragm in the Deltagate.

How did you rule out the BOV? Back in the day we used to call them Type-SSSSSSS, 'cause they leak so often.

Is the wastegate dumping to atmosphere? If it is you would hear it... and there wouldn't be a "pshhhhhhhhhhhhh" of boost being lost. It really sounds like a boost leak. Might be a coupler or a dead IAC.

Braineack

iTrader: (62)

does it sound like this?: https://www.miataturbo.net/braineack...s/badspool.wmv

Fireindc

iTrader: (13)

Alright, i know its not the blow off valve, because we actually clogged it with the cap of a bottle of water and duct tape, theres no way it could have leaked at all.

It sounds similar to that video braineack, but not quite as loud of a spool, or as clean sounding as that and when we let off of the gas it would make a sound like the bov was stuck open, but in fact there was absolutely NO way that it was open because we had it completely clogged closed. - and it spools later than that.

I was thinking it could be the wastegate sticking open, and the wastegate is venting to atmosphere(so is the bov, but i swear we ruled it out haha)

Thanks a ton for the replys, really!

magnamx-5

iTrader: (7)

what does his boost gauge say? is he hitting 0 vac at all. did you try blocking off the wG and seeing if that helps. sounds like there is a leak for sure but since you dont here to much different in exhaust sound it is most likely internal. also how do the compressor blades look? oil in charge pipe? if the bearing went and th ecompressor ate itself then you will see by looking. simple free checks ftw

Braineack

iTrader: (62)

the noise in my video is the compressor blade hitting the housing walls...enjoy that one

i'd want to inspect the turbo at this point, sounds like the bearings & seals are wearing down and it needs a rebuild....inspect both the turbine and compressor blades.

TheBandit

iTrader: (8)

Sounds like to me that you blew an IC pipe off. May sound redundant, but I didn't see anywhere that you had checked. As for the oil, does he have a restrictor in his oil feed line? Sounds like he blew out the rear seal of the turbo with too much oil.
-Michael-

Fireindc

iTrader: (13)

you are EXACTLY right.

I didnt realize that it wouldn't make any boost at all if the turbo needed a rebuild, but i checked shaft play and wow, like an inch of movement in every direction. Also a few blades are bent in there.

Thanks a ton guys, i can always count on you guys

cjernigan

iTrader: (13)

You're gonna loose all kinds of turbo efficiency and spool with bent fins. Start looking for new wheels to replace those, even a used one with a few nicks it better than one with bent blades.