* * First GS-T, weak top end?

[allthrottle]

This is my first time owning a turbo DSM and I'm just getting to know it. The car is mostly stock, except a big 16g and modified air box. It's boosting 8-10 lbs and power comes on strong, but seems like it's lacking guts over 5800 rpm. What should I expect with the powerband? Is this normal?

 

[cheap90gsx]

maybe the ecu is retarding the timing at high rpm. check for boost leaks.

 

[MichaelSuch]

You need a logger with that 16g. You're most likely maxxing out the injectors, making the motor knock and retard the timing. I would take it fairly easy (don't rev it more than 5k RPMs) until you can get a logger and see what's going on. Change the fuel filter, rewire the fuel pump, and run good gas, that should help out a little.

 

[nyTalonTsi]

Agreed get you a logger. Check the classifieds on here. I wonder if the previous owner did any supporting mods for that 16g. Do you have an aftermarket boost gauge telling you 8-10psi?

 

[allthrottle]

I'm just going by the factory boost gauge, so I'm kind of just guessing it's between 8-10lbs. The previous owner only cut the airbox and removed the silencer, he bought the car from an older couple who had the big 16g put on when the factory turbo went. I haven't noticed any other mods. It does have a red valve cover.. do they all come red?

I've swapped in a set of bpr6es plugs, changed the transmission fluid, and replaced the injector seals. I haven't gotten to the fuel filter or rewiring the pump yet, but I always use 93 octane.

And for the logger, do I need an eprom ecu for that? I opened my eecu the other day and it didn't have the socket/chip in it, so I don't think mine's an eprom. Do I need the palm pda, or can I just use a cable and adaptor hooked up to my laptop, with an emulator?

 

[Dsmj89]

Get yourself a real boost gauge, a wideband, an safc/2, bigger injectors (at least 650's), a 190 or 255 fuel pump, and a good tune will really help out and waken up your car. Don't forget to do all your maintenance first if you haven't already done so.

 

[gob4sho89]

I would also recomend putting in some bpr7es plugs... 6's might be a bit to much for your application...

 

[nyTalonTsi]

Yeah 550's should be efficient. Get a 1g logger, a aftermarket boost gauge and a wideband. Some RC 550's too. Since you dont have an eprom ecu get a safc. You must have a logger and wideband for a good tune.

 

[slowgsr]

I see this talk about 'eprom' ecu's. I have a ecu from a 94 tsi as well as my 90 tsi. both stock.. I run aem on my 90 and didn't even ponder if the ecu was of any value, just kept it for troubleshooting, the 94 was on a parts car i scraped and figured why not grab the ecu.

Anyways, goodluck with your problem you will love the car once you get it figured out!

 

[knochgoon24]

You need:
***Boost Leak Tester***
Aftermarket Boost Gauge (-30inHg to 30psi works nicely)
Some sort of logger
Wideband O2 Sensor Setup (AEM, LC-1, PLX, JAW)

Then you'll want:
Something to tune with (SAFC or DSMLink <- Also a logger)
Larger fuel pump
Bigger injectors

 

[All_Boost16G]

When I had a stock motor, and fuel system with a 16g, logger, and works. My GST lacked on the big end too. The power came strong, like enough to torque steer you into the curb, but 5000+ it just didn't keep the power going. Think some of it had to do more on the intake side of the motor, so I bought a bigger throttle body, and a EVOIII manifold, and we will see if that helps maybe push the torque curve up some RPMs.

 

[knochgoon24]

Cams would also be an option if you want more top end.

 

[PIMking]

I would also recomend putting in some bpr7es plugs... 6's might be a bit to much for your application...

what?

7's are a colder plug for more perfomance oriented dsm's stay with the 6's they will do fine until your really start boosting and have more parts.

 

[nyTalonTsi]

Cams are not a requirement for a 16g but you will need the basic supporting mods as stated already.