[RESOLVED] 2g mas on 1g idles weird

[Russman1986]

Put a 2g mas on my 91 gsx. I know the mas is good came off my 96. Used the vfaq to make the harness. The car idles ruff and has bad TB response and backfires some any ideas?
I know I don't have a boost leak was tested.

[bryanwheat]

Are you tuning it with anything or using 550cc injectors?

[Bud92gsx]

Did you wire it like this? 2g Maf wiring for dummies

Are you using 550 injectors, a tuner, or stock injectors?

[Russman1986]

It is wired correctly. The 91 is all stock but hard pipe.

[donniekak]

Originally Posted by Russman1986

It is wired correctly. The 91 is all stock but hard pipe.

Then it's not going to work properly. The 2g maf is going to make the car run about 20% leaner without a way to compensate.

[agentorange313]

Originally Posted by donniekak

Then it's not going to work properly. The 2g maf is going to make the car run about 20% leaner without a way to compensate.

^This, same applies to using the EVO mas.

You need a method of compensating, larger injectors or a tuning solution, AFC or ecmlink for examles.

[91stocker]

With no tune, you will need to run evo 550cc injectors. The evo injectors with no tune will run "about" 20% too rich. And like said above, the 2g mas will run "about" 20% too lean on the 1g.

So when combined they almost cancel out. Allowing you to run more injector and more boost on an otherwise stock setup. A pretty effective budget upgrade really. The evo injectors can be had for about $100 on average.

I would still recommend you get a logger on there though. Watch the logs to see how much boost you can get away with. There are numerous free loggers and Do-it-yourself write ups on making your own logging cable for about $7.

[Russman1986]

I have played the DSM game for a wile. I have built alot of cars, I had no idea about that. That car I was building with all of the best of the 1st and 2nd gen parts left over form other builds. Thank you for the info.

[untouchablecc]

Originally Posted by Russman1986

I have played the DSM game for a wile. I have built alot of cars, I had no idea about that. That car I was building with all of the best of the 1st and 2nd gen parts left over form other builds. Thank you for the info.

Same here. I started messing with these cars in 04 with my friends and I just recently found out about the 2g mass on a 1g with 550 injectors. Justin actually told me about this when I went to get a turbo from him a few weeks ago. He said that is how dsmers back in the day got it done before the luxury of link and other tuning programs. I was also informed you could get away with 18-20 lbs of boost. I will be doing this to my 1g daily with some logging software to check for knockage. I just so happen to have a 2g maf laying around and the car already has 550inj

[iugrad92turbo]

Grab some 550s or some evo 560s, get a logger to help, good to go.