NL 6g74 ECU tuning

[neilrsayers]

Anyone running a wideband? 3.5 or 3.8?

I want to know where all the fuel goes

Bloody Pajeros and fuel! I was excited to hit 16l/100 with the 6g75!! I guess it's not bad considering its lifted with 33s

[stumagoo]

mine runs around 20l/100km in 50-60km areas around the city, 14-16l/100km on mixed driving and 10-12l/100km on freeway only sitting at 100kmh. Off road is where it really chews fuel....... would not even guess that looking at easy 40-50l/100km's

[neilrsayers]

Just a little update - i've cracked open my ECU and found that its chipset is an MH7202F. I think this means that i should have read my ECU with evo5-6 read templates. When i originally pulled down the maps i used the tme 6.5 template and it still worked fine, it may be problematic when i go to flash the ROM. I would check again to confirm, but i haven't bitten the bullet and bought my own open port cable (~$300!!) and have been using a friends

It seems that the Pajero may have multiple different ECU chipset types, so its worth opening up the ECU and checking if you plan on flashing it in IMO

I'm fairly confident i'll be able to correctly read the MH7202F ROM and be able to re-write the modified maps successfully, but I've bought a spare ECU incase i brick one in the process. I won't be able to test my theories until early novermber, unless i buy my own open port cable...

[stumagoo]

reading the BIN is the same format between 5 6 and 6.5 as far as we are concerned - as they are all H8 based its the writing thats the issue, when writing you have to use the correct one and for your chipset its the evo 5/6 one, as is one of mine - the other is the 6.5 read file. I have succesfully read both form either though

The 7202 chipset uses the H8539F memmodel where the 7203 uses the H8539FA

[neilrsayers]

Just a little update - i've cracked open my ECU and found that its chipset is an MH7202F. I think this means that i should have read my ECU with evo5-6 read templates. When i originally pulled down the maps i used the tme 6.5 template and it still worked fine, it may be problematic when i go to flash the ROM. I would check again to confirm, but i haven't bitten the bullet and bought my own open port cable (~$300!!) and have been using a friends

It seems that the Pajero may have multiple different ECU chipset types, so its worth opening up the ECU and checking if you plan on flashing it in IMO

I'm fairly confident i'll be able to correctly read the MH7202F ROM and be able to re-write the modified maps successfully, but I've bought a spare ECU incase i brick one in the process. I won't be able to test my theories until early novermber, unless i buy my own open port cable...

Well i did end up buying my own open port cable because i was too impatient.

With much thanks to Stumagoo and Salt36, i've been able to create my own map based on a blend of 6g75 hi/low maps, and successfully write it to my ECU

So far so good, it feels very strong after 3500 RPM! still waiting on the dyno tune so i can see how much we can get out of it on 91RON, but i'll hopefully get there by November.

[BerKo]

Any news on the 91 RON tune? I'm seriously considering a 3.8L swap but the need for premium is a real downside.

[neilrsayers]

I only ran my first tank on 98. Nothing seems to be out of the ordinary on the 91 after a couple of thousand kms. I've been messing around with some pulley issues so i haven't managed to get a dyno tune yet, but it generally feels pretty good. The fuel econ i've had since the 6g75 on 91ron is 15.9l / 100 km in town only (mostly <5km drive to work and back, a/c on), or 14.7 / 100 mixed town/highway. I haven't actually done any road trips yet, mostly due to lack of confidence the wobbly brand new harmonic balancer that chews the a/c belt

I believe Jazz9 has had over 15000kms on 91 with his 6g75 with stock NL maps and has had no issues.

Generally i only pulled away timing in low rpm medium load areas of the map. In high RPM high load , the standard 6g75 maps were more aggressive.

A friend will have his wide band when he visits for the holidays, so ill see how it feeling looks and maybe we can tidy it up a bit more despite not dyno

[BerKo]

Thanks for the quick reply Sounds like they run better on 91 that I'd first thought.

Yeah with a wideband you'll get a good idea where it is running rich and lean and might be able to work out exactly where you need to target.

[jharrland]

It has been over a year since I fitted my 380 motor - always has run happily on 91 RON, never has it pinged. It does better than 11 litres per 100k cruising at 100 km per hour- the only modification I made was to fit extractors and a full straight through system. Much better power than the 3.5 - so I am very happy - best thing I ever did.....

[BerKo]

It has been over a year since I fitted my 380 motor - always has run happily on 91 RON, never has it pinged. It does better than 11 litres per 100k cruising at 100 km per hour- the only modification I made was to fit extractors and a full straight through system. Much better power than the 3.5 - so I am very happy - best thing I ever did.....

Now that it sweet.. you running stock tyres? auto or manual?

Did you use bare 380 block and pajero everything or did you use the 380 fuel system or anything else?

[jharrland]

G'day Berko - I am running Mickey Thompson STZ's on 16 inch wheels.
380 engine and heads - the inlet manifold, rocker covers and sump from the 3500 engine.

[neilrsayers]

I only ran my first tank on 98. Nothing seems to be out of the ordinary on the 91 after a couple of thousand kms. I've been messing around with some pulley issues so i haven't managed to get a dyno tune yet, but it generally feels pretty good. The fuel econ i've had since the 6g75 on 91ron is 15.9l / 100 km in town only (mostly <5km drive to work and back, a/c on), or 14.7 / 100 mixed town/highway. I haven't actually done any road trips yet, mostly due to lack of confidence the wobbly brand new harmonic balancer that chews the a/c belt

I believe Jazz9 has had over 15000kms on 91 with his 6g75 with stock NL maps and has had no issues.

Generally i only pulled away timing in low rpm medium load areas of the map. In high RPM high load , the standard 6g75 maps were more aggressive.

A friend will have his wide band when he visits for the holidays, so ill see how it feeling looks and maybe we can tidy it up a bit more despite not dyno

I take it back - have had pinging with extra timing in this 40 degree heatwave!! 98 ron fixes it though. I think the peak torque areas of the 6g75 need to be looked after (3500-4500RPM) a bit more careful than how i've been going at it. I've pulled it back to similar timing as the stock NL at 3500-4500, whilst keeping a few degrees of extra advance in the high rev range. It seems much nicer now. If only the NL had a knock sensor

I did run the complete NL ignition map from 3500 RPM and it was sluggish without the extra timing after 4500 RPM > with the load value > 60. If anyone does get a tune, i recommend you have a look at adding timing there.

Ive had a look with a wide band too - the AFRs track very will with whats specified in the maps. I've leaned mine out about 2% in the top end. instead of hitting 12.5:1 its going about 12.8-13.0:1. This may have been an exercise in futility as it was done during a road tune. It would only really be worth it if it increased power a bit.

All in all, the stock maps seem to work quite well in my opinion. There is a bit of room for improvement but i dont really think its worth losing sleep over!

[stumagoo]

Great info buddy

[neilrsayers]

I take it back - have had pinging with extra timing in this 40 degree heatwave!! 98 ron fixes it though. I think the peak torque areas of the 6g75 need to be looked after (3500-4500RPM) a bit more careful than how i've been going at it. I've pulled it back to similar timing as the stock NL at 3500-4500, whilst keeping a few degrees of extra advance in the high rev range. It seems much nicer now. If only the NL had a knock sensor

I did run the complete NL ignition map from 3500 RPM and it was sluggish without the extra timing after 4500 RPM > with the load value > 60. If anyone does get a tune, i recommend you have a look at adding timing there.

Ive had a look with a wide band too - the AFRs track very will with whats specified in the maps. I've leaned mine out about 2% in the top end. instead of hitting 12.5:1 its going about 12.8-13.0:1. This may have been an exercise in futility as it was done during a road tune. It would only really be worth it if it increased power a bit.

All in all, the stock maps seem to work quite well in my opinion. There is a bit of room for improvement but i dont really think its worth losing sleep over!

There is an iat temp correction map that seems to have 0 correction from factory. When I'm running 91 Ron in a heat wave again, I may play around with it. I'm thinking of changing the scaling (jumps from 23 to 40 or so degrees for iat, will change 23 to a value between 30-35) and pull a couple of degrees out at 40 degrees. Im changing the scaling as interpolation would make it start pulling timing at 23 degrees iat otherwise!

[stumagoo]

yeah I have done that in my maps, both IAT and Coolant temps, have 0 correction, I have pulled 3 deg in IAT's and 3 when coolant gets over 100, not alot but it was the first tuning mod I did when I started playing on dunes. especially seeing as where I was that was often at air temps around 40 deg