E39 GMH 3.0 SIDI: 91 vs 98 Octane

[kangsta]

Simon, do you have logs of a few WOT runs you could post? be great if they included cam timing too

[swingtan]

Hi Kangsta, sorry, I'd missed your post. Let me get a couple for you.....

[swingtan]

OK, here's some WOT data. It's a series of WOT sections from a few log files joined together.

E39_SIDI_WOT-ULP91.efi

I still would like access to the table that limits the ETCTP % under 3000RPM though. I've done some testing to fudge the throttle opening and can get more actual throttle under 3000RPM, but it tends to mess up a lot of other stuff.

Another interesting point is the "minimum MAP" setting for the torque control settings. This thing is really interesting as it will change throttle opening to maintain a "minimum" MAP level. Needless to say, setting this to 100kPA is not a good idea ( yes, I tried this ), it opens the throttle to maintain the set MAP level and results in a car that, with no pedal movement, will drive its self up to the speed limiter.....

As you can probably tell, I'm really working on a "poverty" tune for this controller. Running it on 91RON ULP and keeping the car bog stock, the 3lt motor is really under powered in this configuration for a heavy car though. If I can get my hands on a stock HSV 3.27:1 diff for the right price I'd be tempted to put it in. Otherwise it might have to be a 3.45 from a manual car. The later is going to be easier to come by though.

Simon.

[GMPX]

the 3lt motor is really under powered in this configuration for a heavy car though.

A poor decision by GMH for sure. I'd be interested to see how they drive in a CTS, Equinox etc. But what choice do we have out here? I don't want an SV6 just to get the 3.6L, though that should have been the standard V6 across the range. I also don't want a 6L for the wife to do the running around in. My father in law has a 3.0L Berlina too, he summed it up well, it's a great car, if only it came with the Falcon's 4.0L motor. I hate to think what these 3.0L's will be like on a hot summer day towing a boat, van etc. I must confess Simon, since getting to Cruze to play with, I'm 'over' the 3.0L. If there was a better option out there for a wagon, we'd get rid of it. If 'only' Holden made the Commodore with the 2.8L Duramax (like in the Colorado), 346 lb·ft @ 2000 RPM.
Unfortunately the 3.0L SIDI problems extend beyond being able to fix them via tuning. Vehicle weight can't be changed, cubes can't be changed and the two are too far apart to make it nice to drive. It's the peak torque point that is the problem (223 lb·ft @ 5700 RPM) compared to the older VE 3.6L (non SIDI) (240 lb·ft @ 2400 RPM). Interestingly the LFX (which I think is just a 3.6L version of the LF1) has peak torque back down where it's needed (258 lb·ft @ 2800 RPM).

[swingtan]

Yeah, exactly right Ross. Hence why I think a 3.45 diff would help a lot. I'm going to be towing a big heavy trailer just after Christmas, so I'd like to have a car that will at least move up a hill....

Any chance on that a table like {B8801} ( from the Regal CXL Turbo cal ) would remove the throttle limiter off the line? Once it hits 3000, it really takes off but up to there it's yawningly slow....... As mentioned, I've belted the torque model in that area to make the ECM think it's not making any torque, and the throttle opens further and feels better, but it really messes with normal cruise driving. Hence the feeling that the ECM has a "max torque limit vs RPM" table.....


Simon

[GMPX]

Been there done that with the Regal thing, unfortunately all it does is squash down the usable power in to a smaller area ( I sort of touched on this in Chucks E38 throttle thread).
I actually don't have an issue with the full throttle power (apart from lack of it), it's the part throttle lack of torque that is the issue, it can't get up a slight incline without down-shifting two gears, I don't see how that can be fixed in tuning when by design the engines peak torque is at 5,700 RPM.

[swingtan]

Yeah, I see what you mean, I'd still like to try 100% throttle below 3000RPM though..... The diff gear change "should" make a difference, if I can get something at a good price. I guess I should also test the speedo settings in the tune to prove I can correct for the change in gear ratio. I'm also releasing the TCC a bit sooner to try and lift the RPM before the down shift occurs. It helps a little, but it's no V8 killer.

[GMPX]

I'd still like to try 100% throttle below 3000RPM though

Sorry but I'm not currently chasing that one down. I'm sure if it sees 100kPa at WOT then the ECM is happy to leave the throttle where it is. Doesn't seem to affect boosted engines (Cruze and Regal), I'm not sure about other engines using the E39 like the N/A 4 cyl ones.

[ScarabEpic22]

Ross, do you guys get the 2.6L and 2.8L I4 Duramax engines in AU/NZ? I would KILL for one here in the states, I love the 4.2L I6 P10 in my 02 TB but would happily swap a 2.8L Duramax into it.

If they do, wonder how much it would cost to ship stateside...you cant get them here.

[GMPX]

We've had the 'little' Duramax engines for a while, but, they are only available in something similar to the Colorado in the US. Which is fine, but I don't need a vehicle like that.
I just don't understand why Holden won't stick these Diesels in the Commodore, charge an extra 4 or 5 grand if they must. Diesel passenger cars are quite popular here in Australia, but only in European built cars, none of the local stuff has them.
The only downside is, the last time I looked in the engine bay of one of these Diesels the ECM was a Korean made one with no brand name on it, so who knows what it is.
I have no doubt with a tune up one of those 2.8L Duramax's could match a GenIV for torque.