Another comp. surge problem

[bmxrider154]

I have the scm 50trim currently and was completely satisfied with my setup until the other day. I have been on a conservative tune due to a few kinks ive been working out. I was on 19psi with an unmodified 1g bov and it held strong...possibly leaking in 4th gear? Anyway, i found a boost leak (lower piping) fixed it and now boost went to 20-21psi with compressor surge. I dont get the surge at lower boost, only when it reaches about 19psi. It surges(flutters) while im at WOT and maybe a little when i let off. I did the dodge mod today hoping it would cure my problem and didnt really help. It really doesnt make sense, i would think the valve would leak before it surged...? Any help would be greatly appreciated.

-bryan

 

[bmxrider154]

Dont think it is surging, i think its due to increased pressure. Like i said i did the dodge garage mod, but i didnt put the brake line in there i just left it open. That shouldnt make a difference should it?

 

[sbiggi]

Sounds like surge to me.

My brothers and my 50 trim both surge at low rpm in 4th and 5th.
The turbo is trying to put more air into your engine then it can consume.

Either change your driving style or or you need more mods to get the air in easier.

 

[shleppy]

See if it goes away if you downshift before boosting in 4th or 5th, if it does then its surge and you know the solution to your problem

 

[bmxrider154]

Sounds like surge to me.

My brothers and my 50 trim both surge at low rpm in 4th and 5th.
The turbo is trying to put more air into your engine then it can consume.

Either change your driving style or or you need more mods to get the air in easier.

go back and read the first post...i only get a flutter under full boost at WOT in higher rpms, not while cruising

Yes, i know you will get surge when putting that much load on the motor, which is why i dont.

 

[sbiggi]

go back and read the first post...i only get a flutter under full boost at WOT in higher rpms, not while cruising

Yes, i know you will get surge when putting that much load on the motor, which is why i dont.

now boost went to 20-21psi with compressor surge
I dont get the surge at lower boost
It surges(flutters) while im at WOT and maybe a little when i let off..

Wow, you just defined surge. Read your own post over.

Obviously your bov is leaking or your engine can't take in the air.
My Tial will flutter if I boost ~21 psi starting before 4500rpm, which really only happens in 4th and 5th gear.

Edit: My stock crushed valve wouldn't hold past 18 psi and it fluttered real bad at light throttle and 1-5 psi

 

[CanadianTSi]

As stated Compressor Surge happens when the Turbo is trying to force more air into the motor than it can consume, the air backs up through the IC piping and slams into the spinning turbine wheel...not good for the lifespan of your turbo. It has nothing to do with your BOV...

There are a few solutions. A) Turn down the boost. B) Do a Mod that increases the VE of your motor (cams, SMIM etc.) C) Not sure if you have an EBC but if you do try turning down the gain and see if that helps.

 

[bmxrider154]

I know exactly what compressor surge is.

I just dont see how 2 more psi (21psi) would be too much for the stock manifold/cams etc. and cause surge.

I still believe it is bov related.

I am going to tighten the arm on my wastegate, ive heard that could cause some fluctuation in boost.