ok, let me give you alittle background.
currently my TA is supercharged,
i want to tune the current setup via MAP ,

i also plan on pulling the blower off and turboing the car once i get some money (3-4 months)

here are my questions:
from looking at the tunercats software it shows the you can run the car map, but it only shows 1 bar.
does anyone know if that is one bar including vacuum (so a max of 3 psi)
or does that mean 1 bar above atmospheric pressure?

im under the impression that i cannot tune inrealtime on my car (95 ta) because it is a flash, not a chip. can anyone verify that?

what are people using for datalogging when using tunercats. i didnt see where you could setup tunercats to datalog.

i will probably be switching over to a full standalone (BS3, FAST autronic etc etc) when i get everything finished. i want to make sure fi i buy tunercats, it wont be worthless after 3 psi.

thanks in advance.

 

TC will not do boost enrichment or boost spark retard. The 95 LT1 tables only go up to 100KPA which is basically atmospheric pressure. The only way to tune a 95 LT1 for boost is to add enrichment based off of RPM. If you're running substantial boost, the Mass Air Sensor will max out and arbitrary power enrichment vs RPM is the only viable solution. Also no way to pull timing under high boost. You would need to pull timing out of it the whole way which could make for a sluggish curve under low boost situations.

The best scanner I have found for the 95's is Datamaster and a WB setup with logging. The WB doesn't interface real well with Datamaster so you'll need 2 separate logs to work with to help make tuning decisions.

HP Tuners has tuning software for the LS stuff and has the capability of rewriting the PCM operating system for 2bar boost. That won't really do you much good unless you convert to the LS PCM. Thats typically not a simple task as the LS uses a crank reluctor for ignition and injector timing signals and the LT1 uses Opti signals for ignition and sequential injector timing.

Your best bet, If you're going to run substantial boost is to step to an aftermarket system. JMHO


Steve

 

I thought I heard (or read) at some point that someone had >1bar MAP sensors working on factory LT1 PCMs. E.g. if you used a 2bar MAP sensor, you basically double the kPa values in MAP sensor based tables in the PCM (the 50kPa column is actually 100kPa). I wish I had more details on it, maybe try the Forced Induction section of the forum?

 

i was wondering if anyone had (or could get) a screenshot of the a map for a blown or boosted lt1.
im not looking for the cal, just a screenshot of the fuel and spark tables would be enough.

VinceTrifecta -- that is essentially tricking the MAF to think it is only seeing half the air ir really is right?
what can be done about timing though?

 

This applies to the MAP only.

That means your timing table and VE table suddenly scales to 200kPa. You'd have to scale back the existing table to fit within 0-50kPa, and fill in whatever you want from 50-100kPa, which is really 100-200kPa.

I am not sure that you can just plug in a 2bar MAP sensor and scale your tables, though. That's the part you should do some more research on.

 

is the 100 kpa a limitation of the tunercats software, or of the lt1 map,

could this be used to get around it:
http://www.lingenfelter.com/store/lp..._lpe-4232.html

 

You might try asking about the 2 bar MAP over in the Forced Induction forum. It's been a while, but I think I remember people have done a 2 bar on LT1 OBD1.

 

i read up on it alittle bit today,
im trying to stay away from any kinda of hacks though.

im trying to decide if i should get a pcm editor, or if am gonna go full standalone.
if the stock pcm will alow me to run up ~10-12 psi, then ill do that. if not, i dont want to have to pay for tunercats or lt1edit if i can only tune to 1 psi

 

It's a limitation of the GM LT1 code in the PCM. The VE table only goes up to 100KPA. And there is no table for Added enrichment based on MAP. Typical code that is set up for boost would have a table called Boost Enrichment. The table would be a fuel adder factor vs MAP and would go up to 200KPA , good for about 14# of boost, or 300KPA (20 ish #'s of boost). There would also be a corresponding Boost Timing table (Timing deduction vs MAP)

HP Tuners actually rewrote the GM code for the LS stuff to include such tables. No one has ever redone the LT1 code however. Maybe it's a matter of space on the EEprom on the LT1 stuff but most likely it's purely a matter of economics. There's just not enough demand for boosted LT1 code to justify the research and development of rewriting the code.

Regards,

Steve

 

that is what i was afraid of

so anyone running any type of forced induction on a lt1 pcm is running some sorta hack.

im looking into big stuff 3 now,
no sense in buying a temporary system (tunercats/lt1edit) when it wont do what i want it to.