I have a b18b, turbo of course. Im using a GE vacuum manifold with the main source t from the IM to the brake booster line. I have the top line of the wastegate going to the boost controller, and the side source going to my Vacuum mani. Right now my autometer boost gauge has gone wacko and dosent read accurate for crap. So im using my boost controller as my boost gauge for now. I have the stock map sensor in now tuned on uberdata so i really dont want to go over 11 psi. My boost controller is turned off totally so it does nothing but read/ record peak boost so my wastegate "should" open at 10psi. Every time I go WOT i get spikes into the 12psi range...EVERYTIME. Yesterday at the track my boost controller recorded 2 peaks of 13.00 psi and 14.10psi. Which I know can not be good using this stock map.

I have the tial 38mm with the 10psi spring, a short tubular mani (like cc-fabs chuck norris) with the wg elbow right off the middle front to read from all runners.


Any idea whats going on? Once i get a lower PSI spring i can actually use the boost controller and set the limiter and warning. I also plan to get a new map sensor in a week when i will see my tuner again. Even on the dyno it recorded peaks of 11.3-, 11.4- and 11.6- with the boost controller off and doing nothing.

I know the WG is working because i have a open dump and at WOT it sounds like a freight train.
Any ideas what to start looking at? I think its just spikes and not creep, but i cant really watch the controller and drive at the same time.

 

anyone?

I got my boost controller to limit boost at 11.6psi but everytime i get on it it goes right to warn, then limits its.

 

what are you using for EMS?? nothing i'm guessing because you talked about stock map.. (not good)


are you at least running a FMU?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Zakar &raquo;</TD></TR><TR><TD CLASS="quote">what are you using for EMS?? nothing i'm guessing because you talked about stock map.. (not good)

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huh? he said he is using uberdata, nothing wrong with using a stock map for his 10psi goal.

to the OP. do you have an pics of the mani itself? also i know you said the ebc is off but what brand is it? can we have some more details on the setup, just for ***** and giggles.

i would suggest getting a boost gauge that is in good working order for better boost monitoring. do you know for sure its spiking, or is it just creeping in the higher rpms?

 

Thats my exact manifold, made by the same person, same WG placment except mine dosent have a elbow the WG just goes straight ahead.

the boost controller is a blitz dual sbc spec-s

My guess would be its spiking, I actually turned the boost controller on but leaving the value at 0 so it still is working off of the WG. I set my limit at .80 hkpa (11.6 i think) and the warn a little lower. Everytime i get out and "floor it" wot in any gear it will go straight up to the warn and limit limit. WHen I had it off just recording peak boost i was always peaking at 12.6, one time 13.0 and 14.10 psi.

Only when it fully spools and i dont go past like 1/2-3/4 throttle will it actually hold at about 10-1.5psi

 

Iam pretty much in the same boat....I have a h22 running gt35r, and aem ems....boost solenoid is set for 15 psi and i think it is a 10 psi spring in the tial 38 mm wastegate....you can hear the wastegate open up and start to dump then all of the sudden out of nowhere iam up to 20 psi and climbing what could be the problem?

 

anyone????

 

Wheres your vacuum source at? Those can have an effect. I would also get a boost guage and hook it up to your manifold, as that is the boost your engine would actually see.

Stock map, can go past 10, thats not an issue, you just need to know that your last column is set for whatever your boost is. I boost 15 psi, and have done 17 on race gas, on my stock map for over a year now. Not ideal for perfect tunning but think about it, if you were boosting 15 psi, how many times are you at 13 or 14, for me only on the highway in fifth, when i'm messing around. Just my two cents.

 

vacuum source is at the compressor and the boost gauge is hooked up to the manifold.....one minute you here the wastegate then you hear it close back up and you take off like a bat out of hell....i have to let off because it seems that it is going to go past 20psi

 

anybody please help me out here?

 

hey man im tryin to figure out my **** here too...no jackin the thread please.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by swappedcx &raquo;</TD></TR><TR><TD CLASS="quote">hey man im tryin to figure out my **** here too...no jackin the thread please.</TD></TR></TABLE>

Anyway.

But I would suggest getting a smaller spring. The first thing I think you should do is Bypass the boost controller all together. Run a vacuum source right from the intake manifold to the bottom port of the wastegate and see if it spikes then.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by swappedcx &raquo;</TD></TR><TR><TD CLASS="quote">hey man im tryin to figure out my **** here too...no jackin the thread please.</TD></TR></TABLE>

U both have very simialar problems, thats not jacking a thread but more getting more people on the probleme.

 

I have a .5 bar spring on the way, so i guess ill have to take it from there

 

moved the vaccum source and yes it is still spikes.....help