89hatchman

I put in a shitty isis V2 boost controller. I put it in and it'll go up to about 14 psi on the boost gauge at around 5k rpm or so but as I climb in rpm it'll drop down to about 9 psi.

The car feels a little more powerful than it was at stock psi.

I'm also at about 5000 feet altitude so the psi readings on the gauge are probably a little high.

What do you think? Is this just boost spike from a shitty boost controller?

rc1honda

Sounds like you have a vac leak. What happens when you adjust it either way? Be careful though. I would bring it down to stock and build up from there to about 12-14psi .

I don't know your setup so I don't think you really want to go to much higher than 14 on a stock setup. 14psi actually sounds high to me on a stock tune. I would back it off to 10 or 12 and see if you can hold pressure.

89hatchman

I'm running a bleeder boost controller. I think its real shitty and I'll go to a ball/spring as soon as I can. I have a stock T25, stock injectors and tune, stock maf. I do have a front mount intercooler though and vent to atmosphere BOV

My wideband is reading nearly the exact same as I was before the boost controller. No strange knocks or pings under boost.

rc1honda

Yeah than it probably spiking. Get that controller off there before you blow the turbo or worse. 12psi should be the upper limit of the t25. Also pushing almost double the amount of boost on a stock tune is not really smart.

Your maxing the the injectors and MAF out. The ECU is probably pulling all the timing trying to compensate for the load.
Also I just remembered your at 5500 altitude. Pretty much everything your trying to do to this car is back asswards right now.

Really man just junk that controller your doing more harm than good. Get some some injectors, a z32MAF and send your ECU out to enthalpy or something.

Nothing in your setup is made to handle 14 psi. Your front mount doesn't mean shit and is probably just a huge oil separator right now. And having a BOV is meaningless in this situation. It may save some surge but that the least of your worries.

Even with a new boost controller your should not be upping the boost to 14 psi. Boost pressure is pretty much the last thing to upgrade on a engine.

Your setup is not built for 14psi. Keep it at 12 max and that's with the knowledge that your t25 is gonna start smoking sooner rather than later.

89hatchman

alright, I'll turn it down to 12 or so. I think I'm going to make my own ball/spring boost controller. Much simpler and efficient in my opinion. The reason I brought up my altitude is that my boost gauge on stock boost was showing 9 on the gauge. I think at this altitude it reads 1-2 psi over which makes sense. The gauge determines boost levels by comparing the boost to the surrounding atmosphere, which is less up here.

jr_ss

Your atmospheric venting BOV is doing more harm than good. Plumb it back into the intake after the MAF but before the turbo. You'll have a much more responsive and better running car.

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Mikester

As far as the boost falling off post-5000rpm... Welcome to the world of a T25 choking out beyond its efficiency range. Unfortunately, this is normal for the boost to fall like that- It is not capable of holding 14psi in the higher revs.

As far as 'no knocks or pings under boost,' I assure you the motor is knocking its ass off at 14psi. On the stock tune, there isn't enough injector duty cycle to cover the demand... nor with a Power FC (or other standalone) with the injector duty cycle set to allow 100%.

First thing you need to do is plumb the BOV back into the intake stream... Then get injectors and a tune. Your motor will thank you.

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89hatchman

Ya, I'm not running at 14 psi, more around 12 or so, its just the altitude makes it read high. My stock boost was reading 9 on the gauge. But what does it mean if my wideband is reading the same pattern as it was on stock boost? Its a little lean until it hits boost, then it drops from 17 to 13 afr from 5k-7k rpm.