2g overboosting

[t56speed]

OK guys picked this car up today. So im really new with dsms n. ot turbo cars or cars in general just dsms. Its a fwd 95 gst. So when i test drove the car it was making 13 psi. 2 hours later I hit boost on the interstate to get up to speed and the car runs up to 18psi for no reason and hits fuel cut. Here are the mods.

6 bolt swap
Intake
modded upper IC pipe
3inch downpipe
3 inch catback
1g bov
Evo 3 16g
mbc
Stock style IC just thicker than stock one.
Stock ecu
Stock Injectors
Ported 2g mani
Walboro 255
Manual Fpr set at 44psi.

I assume its running really rich.

I called the guy i bought it from an he said its more than likely the crappy mbc.
So tomm in daylight im gonna take it off and run stock boost. Car makes 20psi of vaccume at ide and doesnt have any cels or what not.

Do you guys think thats my problem or could it be the wastegate actuator sticking maybe something else

 

[davidaus]

Do a BLT!!! This happened to me also, Ditch the cheap mbc. Mine was leaking. Get a good quality one.

 

[clipto]

Port the o2 the 3 inch downpipe ganna probably make u creep. Check see if the mbc is crummy or not. Do a boost leak test and start there. Or save up for dsmlink and bigger injectors and boost more .

 

[undefined0000]

OK guys picked this car up today. So im really new with dsms n. ot turbo cars or cars in general just dsms. Its a fwd 95 gst. So when i test drove the car it was making 13 psi. 2 hours later I hit boost on the interstate to get up to speed and the car runs up to 18psi for no reason and hits fuel cut. Here are the mods.

6 bolt swap
Intake
modded upper IC pipe
3inch downpipe
3 inch catback
1g bov
Evo 3 16g
mbc
Stock style IC just thicker than stock one.
Stock ecu
Stock Injectors
Ported 2g mani
Walboro 255
Manual Fpr set at 44psi.

I assume its running really rich.

I called the guy i bought it from an he said its more than likely the crappy mbc.
So tomm in daylight im gonna take it off and run stock boost. Car makes 20psi of vaccume at ide and doesnt have any cels or what not.

Do you guys think thats my problem or could it be the wastegate actuator sticking maybe something else

Sounds like creep to me. If it doesn't do it with the wastegate hooked up to the intake or the solenoid if its still in there, I wouldn't worry about it. Is it a 5-speed or auto. manual fuel pressure is 43 psi and auto is 37.5. Does the boost stay at 18psi or does it spike quick then drop?

Vacuum is measured in inHg for future reference. Run into another DSMer and say that, prepared to be laughed at. Trust me, happened to me already.

20inHg is about 10 psi, a little lower and actually pretty damn near perfect at idle, its what I'm aiming for .. So if you've got boost leaks, they're very tiny.

 

[t56speed]

i have a set of 650s just need link . But yeah it has the tubular o2 housing forgot to mention that. and yeah. Im just gonna BLT it tomm along with installing a wideband and a new set of tires . But def gonna ditch the mbc and just set it up to run on wastegate and drive it like that till i can get Link. I figure its a combo of the crappy ebay mbc and the 3inch downpipe making it creep.

it is a 5speed car and he turned the fuel press up to make it a lil safer since he was running 13psi. Also thanks for the heads up. Im really considering installing the 14b that came with the car and just running stock boost. Any thoughts on how rich or if lean the car is running. Also car just spools up and hits max boost and stays at 18psi

 

[undefined0000]

Oh wait, its you! Honda > DSM guy. Found your first problem that you'll be fixing . Leave those 650s out of the pictures till you can tune. Is the MBC bright blue or pink by any chance?

14b would be fun! Pretty quick spooling. No real way to tell rich or lean without a wideband. The stock 02 sensor uses a 0-1 volt reading and its hard to use (I've tried). I say as long as it drives and doesn't feel like complete crap all the time, you're safe. Turning up the pressure on stock injectors shouldn't make you run too rich. I've got my pressure turned WAY up, like 50psi because I had some boost leaks I had to take care of, so extra fuel for the extra air to prevent lean. Not sure of any adverse effects from doing that other than gas mileage, but its worked. Get the wideband and come back with your readings.

 

[WES_393]

I dont think its creep if it just hits 18psi. Boost creep is a steady increase as you accelerate. Like the previous owner said, it's probably an issue with the MBC. Run a line straight from the boost source to the wastegate. That will eliminate the crappy MBC and put you at 9-10 psi, which is the highest you want to go without tuning.

 

[t56speed]

Yep its me man. And no its def dsm>honda. I just miss the ac its hot as crap in AR . And no its kind of a gray looking color. He said it was an ebay one... Fail...

 

[undefined0000]

Yep its me man. And no its def dsm>honda. I just miss the ac its hot as crap in AR . And no its kind of a gray looking color. He said it was an ebay one... Fail...

I was using the carrot as more of a progressive arrow "Honda --> DSM" would probably have been better. 1 ebay part probably means more ebay parts. Watch out for them and get rid of em. You can build DSMs for pretty cheap, but there still is TOOO cheap (like me). Make sure you update your profile picture, and profile info as far as car type and mods. It will help us help you without asking a bunch of questions.

 

[t56speed]

Will do and thanks for all the help. Appreciate it guys.

Ok Wideband installed. Runs 10.0 afr with boost creeping up to 16 to 18psi.
Removed the controller an ran on wastegaten Car makes 10psi an at 6000rpm just starts climbing
up to like 16 to 18psi hits fuel cut around 6500. Soo ive just been keeping my foot out of it.

Ok guys how do i eliminate the boost creep???? Its annoying!!!!

 

[undefined0000]

Will do and thanks for all the help. Appreciate it guys.

Ok Wideband installed. Runs 10.0 afr with boost creeping up to 16 to 18psi.
Removed the controller an ran on wastegaten Car makes 10psi an at 6000rpm just starts climbing
up to like 16 to 18psi hits fuel cut around 6500. Soo ive just been keeping my foot out of it.

Ok guys how do i eliminate the boost creep???? Its annoying!!!!

You have to make sure your wastegate is letting out enough exhaust. I had a leak and I was spiking up to like 15psi no problem, fixed the leak and I'm back down to 12.

 

[WES_393]

When it comes to the 16g (especially Evo 3) you have a well-flowing turbine coupled with not-so-well-flowing wastegate port. The end result is exhaust gasses that continue to flow through the turbine rather than out the wastegate. A less restrictive exhaust system (such as 3" downpipe) will only make the problem worse. So there are 3 options: Install a smaller downpipe, enlarge the wastegate port and flapper hole, or install enough fuel/tuning mods to handle the boost. My personal favorite being the latter option.

But research the subject a bit an I'm sure you'll find much more detailed answers than mine.

 

[t56speed]

Did some quick research. I think itd be in my best interest to install a aftermarket wastegate. Do i have to get a different manifold for that or can install it on my ported 2g mani. I dont get it either..
the car has a ported turbo ported exhaust mani tubualr o2 and still gets creep.... its soo ###. I wanna just install a dump tube or something. This is literally all thats wrong with the car knock on wood.