first start tune...

[ericjon262]

ok, so I am rapidly aproaching the first start of my turbo 3500 Fiero, it's really coming down to all the little things that finalize any engine swap (coolant lines, little wiring details, finding that one bolt you left in that one place a couple years ago...), and I was wondering if anyone had a suggestion for things to look for/do to the tune before I try and start it. I'm running a 3100 computer, IIRC, it's a 2001 MY for a Grand am.

[carbon]

That would be a 3400... if 3100, perhaps Grand Prix, Malibu, Century?

[3400-95-Modified]

Biggest thing I belive is to make sure your injector values are correct, or close enough to allow the ECU to make the engine run using the STFT and LTFT... If you don't have the injectors right then there will be no way it can correct for that change AND flow changes.

I ran my 3400 with the cam on my slight tune and it was fine, Granted the VE and MAF tables needed a lot of work after but with the injector constant correct it was able to start and run and warm up to break everything in.

[caffeine]

Agreed. For startup adjust for injectors (don't forget lag times too!!! Essential for big injectors) and it should run and idle pretty decently

[ericjon262]

thanks! anyone know if DHP can datalog?

[3400-95-Modified]

Yeah it can data log.

[ericjon262]

awesome, thanks. once I get this heap running, anyone want to help me get the tune figured out?

[ericjon262]

Agreed. For startup adjust for injectors (don't forget lag times too!!! Essential for big injectors) and it should run and idle pretty decently

Do you know where Lag times would be listed in DHP or tiny tuner?

Thanks-

Eric

[caffeine]

No idea. It will me a table with ms values vs voltage.

[ericjon262]

found it, thanks for the help!

[ericjon262]

Biggest thing I belive is to make sure your injector values are correct, or close enough to allow the ECU to make the engine run using the STFT and LTFT... If you don't have the injectors right then there will be no way it can correct for that change AND flow changes.

I ran my 3400 with the cam on my slight tune and it was fine, Granted the VE and MAF tables needed a lot of work after but with the injector constant correct it was able to start and run and warm up to break everything in.

I take it by injector constant, you mean the injector flow rate? how did you calculate it? I'm having trouble getting the car to idle at all, got to have my foot on the throttle to keep it running. Logs show it's running rich as fuck.

[3400-95-Modified]

Well the bin I started with was 19lb injectors... so I took that divided it into my current injectors and got the ratio... then multiplied that by the current BIN IFR or ms/gram value that's in the ecu. Just remember the number in the ECU will DROP not go up... Seeing how it's time per gram of fuel... larger injectors flow 1 gram much quicker.

I also have some charts that are supposed to give you proper scaled rates for fuel pressure related to flow... I have mine scaled like the newer ECU's even though my original bin had a static value for all map ranges. I feel it ends up with a better tune if you tell it the injectors are flowing less at idle vs WOT because of the fuel pressure change.

I'll double check my worksheet and see if I can get it up here for you to use.

[ericjon262]

that's the same way I did it. I'm having trouble getting a maintained idle. tomorrow, I'm going to re-calibrate my wideband and try to log the actual AFR. any suggestions?

[3400-95-Modified]

Run without the maf at first and try to log and adjust the VE table. That may be off for your setup to idle properly.

You make also just have to up all the IAC cells to idle at 1000 or so...

[ericjon262]

as a follow up:

I figured out earlier why I was having so much trouble with idle too...



Note: No IAC passage...

well, the LS1 TB I'm running was made to bolt to an intake with the passage cut into it... guess who forgot to cut the passage into the TB... DOH!

so, I cut a passage into the back of the TB, problem solved.



IIRC, N*'s, which use a similar TB, have the passage made into the TB, like how I have modified mine.

Next question, on startup, the car likes to rev way up (up to about 3000 RPM) I haven't been able to see an easy reason as to why. MY IAC looked a little screwy when I cut the passage, so I'm ordering a new one in hopes that it helps.

also, I'm finding DFCO is very violent in my five speed car, I'm going to disable is by setting the disable MPH to 255



is that the best(right) way to do it?

Thanks-

Eric