Delco probie

[Mamba]

Agreed...and your list is mind boggling alright..all down to emissions consideration...I think agressive spark advance ( without EGR valve) would probably commit the engine to higher octane fuels to overcome the inherent problem with knock...other than that I can see no real value in high octane from a performance view especially in the ecotec..strangely though..mine hates 91, tolerates 95 but shines on 98 but only BP ultimate..the others don't make a difference..too expensive to run on 98 though..have to sell the kids to get around LOL...

[Dec_head]

After trying several different fuels i found 98 bp ultimate more then pays for itself i get more k's to a tank.
My girlfriends little 4 cylinder 2 litre buzzbox gets 100k's to a tank more on ultimate and oddly enough very similar on ethanol based

[Holden202T]

it really depends on the engine combo as to how it responds to more timing.

also the age of the motor, amount of carbon build up in the cylinders etc all adds to what they can handle....

currently i have a "98 only" timing map in the ecotec, it goes noticably better but needs 98 .... having said that, the improvement is only really worth it if you want HP ... i don't seem to get much more economy from it ... so bang for buck its not really worth it but fun

yoda's post is quite valid, you look at the main spark advance and they might be all different, but unless you can compare the actual spark advance that they are getting from the PCM its hard to know whats what.

i've compared vt and vs ecotec heads and by eye cannot see a difference in chamber shape or anything specific like that which might cause differences, apart from minor tuning differences and the EGR i haven't been able to see any differences in the hardware side of the motors ... anyways its not a big deal, aslong as we all know

ok as far as my tune goes .... i've attached it for your perusal ...

do you know how to use the compare function in tunerpro ?

[Dec_head]

Yeah i am yet to check my v8 at the moment going off the dash meter cruising at 100 k's it is saying something like 6.9 litres per 100 k's
Not sure if it's out of wack due to the injector flow rate change or because it runs at a different map value now i did notice it now says o litres per 100 klm's when stationairy.

[Mamba]

Thankyou Holden202, I appreciate that....I've downloaded your updated bin...the only compare function I've found so far is in the tables but still working on it...any advice on compare gladly accepted!!...so main spark advance is different to actual spark advance?? ohh...this just keeps getting better..just when I thought I was getting a handle on it to LOL....ps..love the torana, looks good....love the holley (go carbies!!)..even has grafitti under the wing mirror haha...seriuosly though..your welding and soldering skills are excellent...great job! all the members cars look good and I can only imagine how well they all go...saw jaymes vid's...wow!!...now thats acceleration...sorry, I digress...

I also tried different fuels Dec_head after the beast didn't handle the cane juice option very well..BP ultimate came up the best overall and yeah it probably would pay for itself with continued use...

The ECU considers so many variables that it seems that if one value is altered it affects a dozen others...is it possible to get the right results for the wrong reason??...not sure how to put it...but can you get the result you want in one area but accidently at the expense of another because of a flow on effect...usually successful data manipulation can only occur if all other variables are taken into consideration...you have to have a good handle on all aspects of engine management....sensors, variables etc...

[antus]

generally speaking most of the modifiers, coolant temp, air temp, voltage, etc etc are good enough in the factory state that if you only touch the main tables, (fuel and spark) and the static configuration things like pulses per km for speedo calibration or injector for flow rate for an upgraded item, you should end up with a decent tune. If you understand enough to go further you can, but for most cases you shouldn't need to.

[Mamba]

Thanks antus.....makes sense to only adjust what is required to achieve the desired tune...at the moment , I am swimming in information..all good..just taking time to get through it....Tunerpro's V4 help file is good for training newbies and Holden202's / delcowizid bin and xdf files (loaded in V5)are great..puts are more realistic touch on things....

I can use the compare function holden202...just had a look at it..without any family interuptions...still looking at the shift changes.....certainly looks less agressive..still perusing both...all looks good!!....the fan1 and fan2 is the two speed fan isn't it....it looks like you're working along the same lines as myself with regard to tuning...

Also just read an interesting piece by a calibration engineer in the US...apart from re affirming the complexity of the delco setup every para..his idea of spark advance is to utilize a dyno...adjust the spark until knock and then retard 2 degrees each time...does that sound right??

[Holden202T]

well if your using a dyno for timing you should be finding the peak the torque number ...... more than likely 2 degrees back is pretty close to it ....

because i have the ecotec in a torana i don't have the 2 speed fan option cause im missing the BCM so i have it set to turn the fan on to high speed when needed rather than having 2 speeds, thats why you'll see my tune has the high and low speed fan on and off settings at the same numbers.

what you can do, load in either my tune or the stock ckul tune into tuner pro, then go to the compare menu option and select the "set compare bins" and in bin1 browse to the other file.

then when you open stuff it will show the first (file -> open) bin info then when you press compare it will show the bin selected in bin1 compare option

also you can goto tools -> difference tool, in the box tick the defined items only and then in the two pull down select the two bins then hit the go button and it should give you a list of all the stuff thats different between the two bins

what i meant when i said the main spark table numbers might not actually be what the engine is seeing is that is the base timing it will get, but then if there is a temperature based spark correction it might add or remove timing in certain areas, knock sensor also has an effect on these numbers, along with 15 million other variables.

i guess at the end of the day, all things being right in the pcm it should give you roughly whats in the main table, and if you want to add 2 degrees here or there you'll atleast know it should be pretty much 2 degrees more unless it knocks or something like that to retard it in which case it was too much timing anyways.

oh and fueling is just as complex but like antus said, and especially if you have a stock commodore without engine mods most of the stock bias tables should be right and you should only need to adjust the main tables to tweak the tune to suit exhaust or CAI etc.

[yoda69]

Mamba,
Looks like you're well on the way to understanding the Delco in a very short time.
One of the biggest things with tuning is making sure the motor is mechanically sound, fuel pressure stable and where it's meant to be, no vacuum leaks, good spark plugs and leads, air filter, etc. before you start tuning.
Got to remember a VS is now close to 15 years old and things are wearing out and corrode, sometimes just removing a connector and refitting it can make a difference.

I noticed in your earlier post you mentioned overheating, with the changes you've made there shouldn't be a problem, I would be double checking the radiator, waterpump, fans and thermostat before playing with fan settings, especially if it has been getting progressively worse.

I had problems with a mate's VR where the vehicle was getting hard to start and and low speed/idle fuel trims were starting to max out trying to lean the motor out based on a data log file. We checked that the injectors weren't leaking as extra fuel was getting in somewhere, tracked it down to the fuel pressure regulator was leaking fuel out the vacuum outlet up the vacuum house and dumping it directly into the throttlebody. New fuel pressure regulator and all good.

yoda69

[Mamba]

Thanks for the compliments guys!! ...thanks for the info on comparing bins Holden202..I'll go over the program slowly and make comparisms (Tunerpro is impressive!!)...all good... you're right Yoda69..the VS is not a project car but my only car (Berlina is my wifes and totally stock...no touch it!!) and 15 years old at that..basic changes to aging components make a noticable difference. I've had the car for so long I hadn't noticed the subtle decline in some parts..until they fall apart completely...more reactive than proactive approach to vehicle maintenance....

The overheating has been solved..in a technically speaking, seasonally adjusted kind of way..most pipes, thermostat (now 80c) and radiator have been repkaced but it still gets really hot in traffic (around 3/4 up) and I like Holden202's bin that shows an earlier operation of the fans keeping the engine cooler....

Thanks again for all your help....your patience is astounding...the assistance you have provided me in understanding the delco engine management system is appreciated..couldn't have done it without the kind assistance of members on this board...sorry for all the dumb questions, I really had little yo no idea of EFI...but all the advice has helped tremendously...I have been able to sort fact from fiction in my own notes that have accumulated over time..I was way off track in some areas..embarassingly so...still studying EFI theory but getting there.....thankyou!!....