two stupid questions, please look anyway

[JiveMasterT]

Ok, two stupid questions, I searched but did not find exact answers.

First off, without me taking off the intake pipe on my car and measuring the inlet size of my turbo, how can I find out how big it is? I need to get a coupler that goes to it from a boost leak checker and I wanted to know the size. It's a stock t25.

2nd stupid question is... my home made boost controller spikes to 17psi and then settles at 15 after i hit fuel cut, no matter what so instead of fiddling with it, I wanted to get a JoeP mbc. Are they going to have the same problem? Is there any good mbc that doesnt have major spiking or creeping issues? I'd put the stock one back on but I can't find it.

thanks for looking...

once again, I did search (it was slow at work), but maybe I'm not very good at it as I didn't find clear answers to my questions.

 

[fiveSFE]

a manuel boost controller shouldnt spike at all if you get a good one. my friend bought one off ebay and he is having the same problems as you.

im running a dawesdevices boost controller and it deosnt spike at all, i got it from dawesdevices.com.

im not to sure what the inlet size is on a t25 since i have a 1g

 

[Lithium_31]

I disagree, with a stock t25, if you have it set anywhere above 12-14 psi it will spike to where you have it set, but it can't pass enough air to hold that boost pressure, so you will see it drop to a pressure it can sustain. Mine spikes to about 18 and settles to 13 in first, and 15 in second on up. Of course I'm at almost 5000' in elevation. The little T25 just can't push that much air.

 

[JiveMasterT]

I disagree, with a stock t25, if you have it set anywhere above 12-14 psi it will spike to where you have it set, but it can't pass enough air to hold that boost pressure, so you will see it drop to a pressure it can sustain. Mine spikes to about 18 and settles to 13 in first, and 15 in second on up. Of course I'm at almost 5000' in elevation. The little T25 just can't push that much air.

Mine does eventually drop off to 13 by redline, and that's to be expected. I'm talking about when it first hits full boost, it spikes to 17 psi and then holds whatever I have it set at on the controller, then it drops off to 13 by redline. But that is no good because the air is REALLY cold right now and spiking to 17 psi in this weather means fuel cut for me.

BTW, still no answer on the inlet size... anyone know? Does anyone have one out of their car they can measure really quick? It is 8 degrees outside and standing outside under my hood is not something i want to be doing.

 

[rice_rocket]

Just get a 2" coupler and it'll be a little big.. you'll be all set... there's nothing for much smaller, unless you want to find a 1.5" coupler and try to squeeze.

Still it sounds like you are going to spike no matter what with the T25 and it'll settle. Turn down your boost, you can't sustain the 18psi anyways, or just don't drive it so hard. Yes some of the JoeP ones or Hallman's would work a tiny bit better since they have an extra "bleeding" point, but I would not say that would help out so much. So either fork out for a good lasting boost controller, or set your boost down or stop having such a heavy foot.