SOLUTION: Different 1st Gear Rev Limit - 3.2 JTS - Alfa Romeo Forum
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Well Happy SOLUTION: Different 1st Gear Rev Limit - 3.2 JTS

THE QUESTION: Does anybody know how to trick the car into thinking it is in 2nd gear (or 3/4/5/6th) when it is in 1st gear???
_____________________________________________

As owners of MANUAL 3.2 JTS engines (159 3.2 etc) know - the rev limit on 1st gear is 6200 and the rev limit on all other gears is 7200.

Well that's just STUPID!

The engine is the engine - it doesn't matter what freakin gear it is in!!!

So the ONLY thing I can see that the computer needs to know it is in 1st gear is the hill-hold function (who the hell needs that anyway). Other than that it makes absolutely no difference to anything programmed into that car whether it is in 1st gear or any other gear.

SO my BIG little question.....
__________________________________________________ _____________________
Does anybody know how to trick the car into thinking it is in 2nd gear (or 3/4/5/6th) when it is in 1st gear???
__________________________________________________ ______________________

This will ELIMINATE the stupid 1st gear rev limit and make it like all the others. The HAS to be a sensor somewhere that it knows its in 1st...

Anyone know ????

Thanks,
Richard.

Rick
159 3.2 JTS Ti Q4 6Spd Manual 2008
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Quote:
Originally Posted by crimson96 View Post
The HAS to be a sensor somewhere that it knows its in 1st...
There probably isn't a sensor at all.
The ECU can work out what gear it is in by the wheel speed (from the ABS sensors) and the engine RPM.
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Quote:
Originally Posted by crimson96 View Post
THE QUESTION: Does anybody know how to trick the car into thinking it is in 2nd gear (or 3/4/5/6th) when it is in 1st gear???
As owners of MANUAL 3.2 JTS engines (159 3.2 etc) know - the rev limit on 1st gear is 6200 and the rev limit on all other gears is 7200.

Does anybody know how to trick the car into thinking it is in 2nd gear (or 3/4/5/6th) when it is in 1st gear???
This will ELIMINATE the stupid 1st gear rev limit and make it like all the others. The HAS to be a sensor somewhere that it knows its in 1st...
Anyone know ????

Thanks,
Richard.

Quote:
Originally Posted by David C View Post
There probably isn't a sensor at all.
The ECU can work out what gear it is in by the wheel speed (from the ABS sensors) and the engine RPM.



It's not stupid(there are lots of reasons),a lot of manufacturers have different rev limits for different gears(especially the Germans)not just Alfa and not just on the Brera

If you want the rev limiters lifted get your ecu remapped
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(Post Link) post #4 of 11 Old 22-02-13 Thread Starter
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To DavidC - I believe it must have a sensor as it can't know from engines revs/speed if the car is at a standstill. It must have some kind of a sensor for the hill hold function - which sets the brake when the car is stopped on a hill but only if the gear lever is in 1st (or rev if on a decline).

To AlfaTuner - I was being a little contemptuous with the "stupid" remark. I meant that for the most part if the engine can handle 7200 - let it handle it! It would make a marked difference in acceleration if it had that extra 1000 rpm in 1st gear - and I can't see the engine doing 7200 in 1st being any different than in the other gears - regardless I'll take the risk (as minute as it may be).

Certainly can get it reprogrammed - but I have not found one company out there that just raises it all the way to 7200 in 1st and leaves it at 7200 for all the other gears. I have seen one that raise it to 6800 in 1st but also raises the other gears - which I am not a fan of. Plus they cost a lot of money - I am looking for a simple "trick" more than anything. Just trick that sensor - if I can locate the damn thing. My guess is it is inside the gearbox - alas!
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Quote:
Originally Posted by crimson96 View Post
To DavidC - I believe it must have a sensor as it can't know from engines revs/speed if the car is at a standstill. It must have some kind of a sensor for the hill hold function - which sets the brake when the car is stopped on a hill but only if the gear lever is in 1st (or rev if on a decline).
From the 159 manual:

Quote:
HILL HOLDER SYSTEM
(for versions/markets,
where provided)
This system is an integral part of the VDC
system and it is provided to facilitate
starting on slopes:

❒ uphill: car at a standstill on a road
with a gradient higher than 6%, engine
running, clutch and brake pedal
depressed, gearbox to neutral or
engaged gear other than reverse;

❒ downhill: car at a standstill on a road
with a gradient higher than 6%, engine
running, clutch and brake pedal
depressed and reverse gear engaged.
At pickup the VDC system control unit
will keep brake force on wheels until
reaching the torque suitable for starting,
or in any case for about 1 second in order
to pass easily from the brake pedal
to the accelerator pedal.
No mention of 1st gear there.
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I would assume the limiter on first is lower to stop you over reving the engine, a good launch with a slow gear change with the car still accelerating could very quickly push it past the rev limit for the engine.

Gus has posted a solution he knows what can and can't done re map wise. Re mapped mine, a diesel I know, but OMG he knows what he's doning on anlything with a Alfa badge.
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I wonder if the variable rev limits for different gears might be something to do with the EU mpg tests where the upshifts happen at a set % of maximum available revs I believe
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(Post Link) post #8 of 11 Old 23-02-13 Thread Starter
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Thanks David C - yes I am aware of that. I know from trying it that if the gear stick is in 1st on a steep incline the brake holds for 1 sec. If you try the same thing on the same incline in 2nd (for example) the hill hold does not work (brake does not engage.) So that is why I believe there must be something somewhere that tells the ECU the level is in the 1st gear position.

And again, I get that manufacturers try to be conservative and account for the dumbest of drivers - but its my car now and I want the extra 1000 rpm damn it
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Quote:
Originally Posted by crimson96 View Post
Thanks David C - yes I am aware of that. I know from trying it that if the gear stick is in 1st on a steep incline the brake holds for 1 sec. If you try the same thing on the same incline in 2nd (for example) the hill hold does not work (brake does not engage.) So that is why I believe there must be something somewhere that tells the ECU the level is in the 1st gear position.
So on a steep uphill slope, does your hill-holder work when you are in Neutral, because the manual says it should?
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Quote:
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So on a steep uphill slope, does your hill-holder work when you are in Neutral, because the manual says it should?
Definitely does not work in neutral must actually shift the lever into 1st.
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Keep looking for a switch/sensor if you want, but I'm sure you won't find one.
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