Dookie,

Thanks for the response. When I upgrade the heads/cam, I'm planning on 42lb injectors. I'm up here at 5200ft. My NA (bolt-ons) WOT runs on the datalogger show 53% duty cycle and thats with 12.8:1 target AF.

I'm installing a V1 S-trim with a FMIC, so I'm guessing I'll see around 6-7psi, still only running the stock motor. I'm guessing this setup would yield 400whp car at sea level, so figure that's around 320whp up here.

First off, I want the MAF gone because its 1 less component to deal with. How is there no advantage to the 2bar map? I'm currently running Tunercats and stock PCM. Without the 2bar, I have no way of controlling timing/fuel under boost.



There is no advantage running the 2bar sensor with small injectors, I kid you not, 0 advantage since that is the whole point. The problem is you are maxing the injectors so there's no advantage of using the 2bar when the injectors are maxed. Do yourself a huge favor and buy larger injectors preferably ones someone else used in this discussion so you know they work and you will only have to tune those in one time vs two times after you realize you need bigger injectors anyway like I did!


[QUOTE]

[QUOTE=onefastmx5;6272628]Dookie,

Thanks for the response. When I upgrade the heads/cam, I'm planning on 42lb injectors. I'm up here at 5200ft. My NA (bolt-ons) WOT runs on the datalogger show 53% duty cycle and thats with 12.8:1 target AF.

I'm installing a V1 S-trim with a FMIC, so I'm guessing I'll see around 6-7psi, still only running the stock motor. I'm guessing this setup would yield 400whp car at sea level, so figure that's around 320whp up here.

First off, I want the MAF gone because its 1 less component to deal with. How is there no advantage to the 2bar map? I'm currently running Tunercats and stock PCM. Without the 2bar, I have no way of controlling timing/fuel under boost.




I mean there is no advantage of running 2bar without big injectors, 42 might be fine, not really sure.

I dont remember but I think I was maxing my 42lb injectors or nearly maxing them at 7psi with just headers and rockers, I dont remember.

Maybe the higher altitude with keep it down.

The supercharger is taking some power to run so the HP the motor is generating is actually higher than what you net at the crankshaft and wheels. 450hp on N/A takes less fuel and less injector Duty cycle than a 450hp LT1 at 7psi.

How do you control timing/fuel with 1 bar map sensor under boost? Because the table ends at 100kpa in Tunercat. Right now, i have timing set to 35* WOT, and for some reason it datalogs that the PCM is running 40.

My timing logs differently also but to get to your ?. I go into % change to air/fuel ratio Vs. RPM at WOT. This is the only way that I now of. If anyone has a better way please let me know.

I understand changing "%change to air/fuel ratio Vs. RPM at WOT" to target around 11.5:1, but how will the PCM account for boosted air at first? So the very first time you go WOT with boost, the PCM is going to have to learn it through pinging and timing retard, and lengthing duty cyles. I have no idea how fast it learns.

With the 2bar SD tune from this thread, the VE tables dictate the fueling. So with a set amount of air, it already knows how much fueling to give it. Also, timing is properly decreased based on boost (55-100kpa). So how does this offer no advantage with stock injectors??? Obviously, this table would need to be modified for my altitude, but it looks like a good place to start.

James

2 bar tune wont do any good with stock injectors because injectors will be maxed out, if your running stock injectors just leave the stock MAP sensor in there since there's no point in going through all the work to get it right when all your going to realize is you need bigger injectors.

Got 42lb'ers in, now time to tune

This does work for saving files in LT1_Edit that would give the "VIEWING ONLY" message.
This does NOT WORK for uploading the saved file to the non-matching LT1_Edit PCM using LT1_Edit's utility, since the utility checks the internal PCM VIN which so far no one has changed.
This DOES NOT work for permanently changing the LT1 PCM VIN.
You can edit with this method using LT1_Edit but you have to use CATS Tuner to upload it, then the next time you download the file using CATS TUNER you have to perform this all over again to be able to save the file in LT1_Edit.

Just stick to CATS Tuner for everything (though it is a bit more non-user friendly!)

You are correct, I use a tuner conversion file to change it to an LT1 file from a bin...

OK at the risk of sounding like a tard, how are you enabling SD in a 94-95 OBDI car? Ive checked the flag on front screen LT1 edit, just unplugged it until it coded and no matter what car wont run with MAF unplugged. Added 30-50 percent fuel in the VE table, taken it out - in case it was just way off,no luck. Starts perfect, runs 1 second then dies. Everytime
Dont want torun MAF for packaging reasons

Not sure on LT1 edit, but tunercats has a checkbox too. I'm still running MAF for now, but if i unplug the MAF car runs and idles without it, just throws SES.

Yea, it should run fine with the MAF unplugged. One time when I was working on my car, I forgot to plug it back in and didn't know it until next time I opened the hood. You may have a bad MAP sensor, or some really screwing tune in the ECM.

Anyone have a SD OBDI LTedit files I can check some stuff against? Its a 408 inch engine, should just have to move VE numbers up or down to get it in the ballpark to run, dont get why it fights so much.

MAP sensor reports back normally ok there

i've been reading this thread for a long time now. and i've been doing this tune on my 92 corvette. in open loop i've got it all dialed in. however when i go to closed loop, the afr under wot keeps getting richer with every shift (m6) car. ive tried all kinds of setting in tunercat, but still cant fix it. but open loop is fine, 12.5afr under wot every gear. it realy picked up alot of power over the old fmu. if anyone knows anything about this please let me know. this is the chiped lt1 same as a 93 z28.

nevermind after reading page 20 again of this thread i see its my iat sensor. mine is located before the supercharger and temps drop apon hard acell. this site ROCKS!!