If you want on-the-fly map changes, then RAM is (usually) the appropriate way to go... programming flash is time-consuming as you have to erase an entire page of memory before changing even a single value. There are ways to keep it all in flash (typically through minor hardware changes), but they're not ideal and won't work in many cases.

Well I really want to know but I don't think it's going to matter anymore because UpRev will never tell us how it works specifically because there are several ways it can be done. For some old school ecm parts and tuning check out MOATES.net. Very informative place you can see the different kinds of chips, emulators, software, cables, sockets, adapters that I'm familiar with tuning. Of course that was pre CAN-BUS, back when all the manufacturers used the same technology and if you knew one you knew them all. Worked great until 96, then they actually made it easier because now you could reflash right through the OBDII connector when manufacturers started using rewritable chips. Some manufacturers still retain this level of setup like GM. The code remains very similar year to year so programs like HPTUNER and EFILIVE are WAY WAY WAY ahead of where Uprev is. They make Uprev look like a real waste of money and give you just an awesome level of control over the entire vehicle. You could set fan on off times, delete egr, change how the electronic throttlebodies work, change ALL of the factory fuel and timing values for idle, turning on the A/C, light load, lean cruise, WOT, Acceleration Enrichment, Target AFR, VE, MAF, TPS%, Main ignition map, decel modifier values, min idle rpm, and many more. The GM stuff for the simple American cars makes me wonder why our cars are called tuner cars when you can hardly do anything with them. On the GM stuff you can even go in and change how you want the automatic tranny to work and shift. You can actually up the line pressure and change shift points from your laptop. If uprev and Cobb could match that kind of control, you wouldn't see half the standalone and piggyback sales you see now. You would be able to have an outrageous setup without having to sacrifice drivability, or traction control, and with out having to ignore the permanent service engine light on the dash. Why:shakes head:?

Is there any chance that hptuners can work on our cars?

From Osiris

At the core of the ECU is a processor that uses 3 types of memory:
- Flash-ROM (internal to the processor). This is Read Only Memory, where the ECU stores its operating software as well as the tables that are used to calibrate/tune the ECU’s operation. This area can only be written to via an ECU reflash (Osiris). The flash memory has a limited number of rewrites that can be preformed before the memory starts to degrade. Once the flash memory has begun to degrade the ECU will have to be replaced. A minimum of 200 flashes can be preformed according to the CPU data sheet, but twice that is likely possible (we flashed the ECU on our development 350Z more than 400 times without any memory degradation).
- RAM (internal to the processor). This is Random Access Memory (read and write) that the ECU software uses to store variables that change in real time such as sensor readings, environmental conditions and changes over time, as well as calculated values that are used for the software control models that manage engine operation.
- Non-volatile EEPROM (external from the processor). This non volatile memory is used to store things like idle adjustments, ignition adjustments, learned idle air volume, VIN, and other static values that vary from vehicle to vehicle. You should not have to deal with the EEPROM, but it’s good to know it’s there.

If someone could post the processor the 370Z ECUs use, I could post more appropriate info.

wow, this is why im scared to do anything that involves tuning. i have no idea what you guys are saying or arguing about. i was gonna go with the cobb but it just seems too complicated, i think ill get a reflash instead

No...Islow is right though. It is an amazing program with total control

Here's a visual from the Audi Motronic system. Seems quite like the Z in that you have limited access using available tools like the Cobb, and only those that have cracked the coding can do complete re-tuning, and all of them are keeping this info close to their chest. The Audi community has the same problems..

http://images115.fotki.com/v663/phot...diagram-vi.jpg

DON'T GIVE UP! That was me 5 years ago you just have to keep trying and research. With the amount of information on the internet nowadays it's like going to community college you just have to make sure you aren't reading bull (don't trust wikipedia but it can get you started).

All the things that the computer controls and how hard it is to access still makes me want to go ITB's with 6 mikuni carbs, pulley crank trigger/msd 6al/dedicated ignition system, lock the vvel open, switch in solid cam sprockets and ignore the shat out of the SES light.

:tup:

:iagree:

The days of ITBs seem to be gone... Well, there's at least the opportunity on my first intended "toy" car, another 240. Keep the KA24DE, stroke it, full build from crank to cams, with ITBs...:excited: The only hard decision will be S13.5 Strawberry Hatch vs. S13 Silvia Coupe vs. S14(v2) heh. If only I had the money to burn.

I've been looking at ITBs for my L28 but it seems like the cost is hard to justify. A well designed plenum doesn't cause turbulence like the butterfly valves on each ITB produces. I think I'll stick with my triple Mikuni's....

I'd get ITB's with gate valves instead of butterflies then it's straight through. I love how much those things cost. You could probably find some large mikuni carbs with the cylindrical slide, remove the needle and float bowl, bore out the venturi for more flow as you wouldn't need it anymore, and bolt them to a 1" spacer plate that would have injector bosses in it. Don't know if they make mikuni's that big though.

Think there is some unintentional misinformation going on here. You can tune with the Cobb Accessport.

In laymen's terms.......Basically the unit is quite slick in my opinion in what it does and how it does it. The Accessport is basically the gateway to accessing your ECU and a regular computer which holds Cobbs tuning software. Upload what's in your ECU (stock program) into the tuning program on a regular computer and you can change whatever you want. Then download it to the Accessport and download it then into your ECU. That simple.

Also you can log data, reset your ECU, diagnose codes to even log 0-60 and quarter mile times. Slick little pooper.

Now the fly in the ointment....... the tuning program is free (the good news), it doesn't work (the bad news). Still under development but you can change fuel/air, rev limit, top speed limiter, etc. However, you cannot change the timing and for some reason the program is pulling out midrange timing on it own. (a bit more of bad news)

Now ya know.

Denny, do you not have access to a local Cob Pro tuner? If that's the case, is that why you are trying to tune it yourself?

Cobb in Plano Tx did the initial tune and frankly didn't work out very well.

When the car was at Cobb wasn't privy to the data logs nor what was being done tuning wise. However, upon being able to log myself and looking at the curve of the dyno output, feel I could have done a better job IF the software was effectively working. An issue that may have thrown off the tuning session is the intake temps were 108 degrees and that may have been an inhibiting factor, plus there were software issues.

Fairly well connected in the local hot rod community and personally know Kenny Tran and Bob Norwood so national level tuners to take the car to really isn't an issue. Basically took two years off from the medical/surgical field and all I did was mod and race cars. At the time sponsored by a dyno shop around cars being tuned every day so feel pretty comfortable doing a basic tune. Lots of people are a lot better than me, some maybe not. The thrill is in the chase which is why I do it myself plus a big believer that you try and learn something new every day.