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Old 1st July 2021, 09:55   #1
Dorchester2
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Default V6 remap

Hello chaps !

I'm living in France as several of you know and I would like to make a remap to get more torque in the low revs and more efficiency.
I called to a well famed garage and they say that all V6 can't be remapped because they have'nt any eprom then not fully obd2 compliant.

What do you think ?

Would it be doable nonetheless ?
If so how ?

Thanks a lot.
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Rover 75 V6 2.5 Auto Connie born 1 July 1999, 24 kOhms resistor, 10 kOhms manual starter, full E85, modified airbox, full derestricted SS exhaust line, power & torque remap -> 202 bhp
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Old 1st July 2021, 12:34   #2
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Quote:
Originally Posted by Dorchester2 View Post
Hello chaps !

I'm living in France as several of you know and I would like to make a remap to get more torque in the low revs and more efficiency.
I called to a well famed garage and they say that all V6 can't be remapped because they have'nt any eprom then not fully obd2 compliant.

What do you think ?

Would it be doable nonetheless ?
If so how ?

Thanks a lot.
V6 maps can generally squeeze out 10bhp or so. They can be mapped, the garage just doesn't have the tool to read a Siemens EMS2000. The same ECU was used in the Mini too. You won't really get any better fuel consumption, they are thirsty engines.

The map is also stored on flash not an eeprom and it is fully OBD2 compliant, but being OBD compliant doesn't really make any difference to mapping it.
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Old 1st July 2021, 13:27   #3
Dorchester2
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Question

Thanks a lot.
So next question is: which tool is needed to help the garage reading the Siemens EMS2000?
Even it's for a light enhancement I'm fully interested. No question of money.
Thank you @Jamiewelch.



Quote:
Originally Posted by Jamiewelch View Post
V6 maps can generally squeeze out 10bhp or so. They can be mapped, the garage just doesn't have the tool to read a Siemens EMS2000. The same ECU was used in the Mini too. You won't really get any better fuel consumption, they are thirsty engines.

The map is also stored on flash not an eeprom and it is fully OBD2 compliant, but being OBD compliant doesn't really make any difference to mapping it.
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Rover 75 V6 2.5 Auto Connie born 1 July 1999, 24 kOhms resistor, 10 kOhms manual starter, full E85, modified airbox, full derestricted SS exhaust line, power & torque remap -> 202 bhp
  • This vehicle was the 7,517th 75 to run off the production line, out of 112,381
  • This vehicle was the 1,190th 75 2.5 V6 Contemporary to be made out of 8,214
  • This vehicle was the 2,032nd 75 in Atlantic Blue Pearlescent (code: JEY) to be made out of 2,572 Atlantic Blue Pearlescent 75s
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Old 1st July 2021, 23:55   #4
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It has long been established that KV6 is not one of these engines that can be easily remapped, nor would you get any real benefit from it anyway. When MG Rover set out to squeeze just 13bhp more out of it for the ZT, they had to fit different camshafts to achieve just that. There are no known remaps out there for the KV6 (that is, real remaps with dyno-proven improvements), even in the UK. And when MG Rover Australia wanted to achieve more out of the ZT 190, they developped the ZT 220 with the use of a Sprintex supercharger...for just 30bhp more.

Furthermore, your Jatco auto transmission would not necessarily safely handle more bhp or torque. The ZT190 engine had to be detuned to 180bhp for use with the auto ZT 180, because of that.

Forget about it. Make sure your VIS motors are working fine and you'll achieve way more by replacing them, if they're faulty, than any KV6 remap would, if it were even doable.
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Old 2nd July 2021, 10:18   #5
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Originally Posted by scoubix View Post
Make sure your VIS motors are working fine ...


Also Arnaud check the VIS balance flap valve which has a tendency to stick in its mid position which reduces torque considerably. It just needs "easing" with some fine abrasive paper.

Make sure that there's no excessive play in the VIS power linkage too although that comes into play only when you floor the throttle.

Each cam cover has a pinhole orifice hiding behind the gauze filter leading to the breather tubing. These pinholes become blocked with carbon deposits, particularly if the 15,000 mile oil change interval has been followed. Clearing these makes a dramatic difference to the performance of the engine. Access to the RH bank cover means taking off the black plastic manifold chamber but the effort is worth it!

Simon
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Old 2nd July 2021, 13:24   #6
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Originally Posted by scoubix View Post
It has long been established that KV6 is not one of these engines that can be easily remapped, nor would you get any real benefit from it anyway. When MG Rover set out to squeeze just 13bhp more out of it for the ZT, they had to fit different camshafts to achieve just that. There are no known remaps out there for the KV6 (that is, real remaps with dyno-proven improvements), even in the UK. And when MG Rover Australia wanted to achieve more out of the ZT 190, they developped the ZT 220 with the use of a Sprintex supercharger...for just 30bhp more.

Furthermore, your Jatco auto transmission would not necessarily safely handle more bhp or torque. The ZT190 engine had to be detuned to 180bhp for use with the auto ZT 180, because of that.

Forget about it. Make sure your VIS motors are working fine and you'll achieve way more by replacing them, if they're faulty, than any KV6 remap would, if it were even doable.
There are remaps out there and plenty of dyno runs showing more power. The Jatco autobox handles the diesel torque perfectly find and the diesel produces a fair bit more torque than the KV6.

Not many companies do want to tune the KV6, probably because you can't get huge peak gains, but it is not about peak gains, for normal driving you want the gains in the mid range.
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Old 2nd July 2021, 14:04   #7
Dorchester2
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Talking

Many thanks to all for your sound advice.
I was aware that there isn't much to get from a KV6 remap.
My aim wasn't at all to get a terrific increase of power: I'm not that foolish...

Just a kind enhancement of torque in the low revs, my autobox when cruising asking for around 1.8 to 2.5k revs.
It's another matter when I give a brave kick down in order to quickly and safely overtake the car in front of me.
Going at my younger son's and back home, along around 1,200 km (750 mls), 13 times I went over 6k revs in an impressive speeding up: what a kick in the ass!
Even I reached 6,666 revs as I'm told by my monitoring Torque.

BTW both my VIS motors are working fine: it's obvious when I go above 3,5k revs. It becomes far more punchy and reactive.
Moreover I've tested them thanks to TOAF: they are ok, like all the rest.
I'd taken the precaution of swapping the old ones for new when I bought the car in September 2017. Shame that at that moment I wasn't aware of Brian Robson uprated ones.

Regarding the cam covers pinholes (I'd never heard of that before, but I'm here to learn indeed!), I bet my precious mechanics has had a close look on that when he took off the cam cover and the like, swapping the plugs, verifying the leads and even taking off the throttle body and fully cleansing it from all its remaining oily gunk.

Oil service is done once a year like other services following the usual recommendations. For example the whole cambelt kit bought at DMGRS was fitted in 2020 after 6 years. The old one was in apparent good nick without any crack but it was done for peace of mind.

Besides using full E85 (octane 105) has a well known beneficial effect: it cleans the fuel system alongside with a better oomph and reactivity and a slightly better power.

In conclusion it looks true that I can't get much more than I've already got at the moment.
You've convinced me and I'll give up with any attempt of getting more if ever by a remap: my good old granny Davis told me that the best is the enemy of the good...
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Rover 75 V6 2.5 Auto Connie born 1 July 1999, 24 kOhms resistor, 10 kOhms manual starter, full E85, modified airbox, full derestricted SS exhaust line, power & torque remap -> 202 bhp
  • This vehicle was the 7,517th 75 to run off the production line, out of 112,381
  • This vehicle was the 1,190th 75 2.5 V6 Contemporary to be made out of 8,214
  • This vehicle was the 2,032nd 75 in Atlantic Blue Pearlescent (code: JEY) to be made out of 2,572 Atlantic Blue Pearlescent 75s

Last edited by Dorchester2; 2nd July 2021 at 14:11..
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