ECU Talk & Removed Rev Limiter

joesouthgate

joesouthgate

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Hi guys,
We removed my rev limiter the other day at ISTS (covering the 5th hole in the dizzy) but it seems to have messed around with my ECU talk a bit.
It now reckons I'm averaging about 50-60mpg (normally 30-40 tops), any idea why it would do this? Its a bit confusing!
Joe
 
Basically covering that hole is a messes up the ECUs timing and calculations, hence why I don't recommend it.

Also allowing it to rev higher wont help you go faster as the car will be unable to make power at those higher rpms, but you probably know that anyway.
 
Yer I do know that lol
Okay cheers Ed, I will uncover the hole again, I just was interested to know why it had done it.
 
NME would modifiy the early Micra Challenge rally car distributors by joining the main timing slot with the TDC number 1 slot to move the rev limiter to just under 7400rpm when they used the standard ecu. The rev limiter then cut in on the fuel shut off. We always found the cars pulled ok to this new limit and I have a demo road car with 115k on the clock which has the same mod and is still going strong when pushed to the limit (famous last words)
The only mod to the standard engine is an exhaust system, and the engine has not been touched.
 
mph said:
NME would modifiy the early Micra Challenge rally car distributors by joining the main timing slot with the TDC number 1 slot to move the rev limiter to just under 7400rpm when they used the standard ecu. The rev limiter then cut in on the fuel shut off. We always found the cars pulled ok to this new limit and I have a demo road car with 115k on the clock which has the same mod and is still going strong when pushed to the limit (famous last words)
The only mod to the standard engine is an exhaust system, and the engine has not been touched.
Click to expand...

that,s interesting matt :cool: 1.0 engine i presume ?
 
No Frank it's a 1.3. If anyone is in Oxford and would like a run out in the car just give me a ring.
 
making these modified discs should be easy enough (I could get new ones cut), should people want them doing :)

though i suppose sometime with a file would be just as accurate :D
 
Posted by Matt (SuperUno) : How do you know which is the No. 1 TDC hole ? Anyone got a pic of a disc, that had either been modded or which could show which holes to link up ?

Luckily i got to try the demo car today and the engine does pull very well all the way past 7K, with no tail off in power, also the 5.1 diff made it great fun :)

As an aside many thanks to Matt for his help and info today, a top bloke willing to help out Micra owners.
 
Suze said:
Posted by Matt (SuperUno) : How do you know which is the No. 1 TDC hole ? Anyone got a pic of a disc, that had either been modded or which could show which holes to link up ?

Luckily i got to try the demo car today and the engine does pull very well all the way past 7K, with no tail off in power, also the 5.1 diff made it great fun :)

As an aside many thanks to Matt for his help and info today, a top bloke willing to help out Micra owners.
Click to expand...

pic of the disc here
http://www.micra.com.au/community/message.php?messageid=32767
i would guess #1 cyl is nearest the 5th hole ? :)
 
well the 1.3 has alot more to give in the higher rev range compared to the 1 litre so would it be worth it?
without the limiter how would i make shor that i dont damage the engine by reving to high?
 
pap29 said:
well the 1.3 has alot more to give in the higher rev range compared to the 1 litre so would it be worth it?
without the limiter how would i make shor that i dont damage the engine by reving to high?
Click to expand...

the shortstroke 1.0,s REALLY thrive on revs, and they have the same valves, ports etc, so they get asthmatic later than a 1.3.
i took my 1.0 to near 9k, but i would,nt like to take my 1.3 past 8k :eek:
i think craig,s was 75hp, mine (piper cams, janspeed manifold etc) must have been near that :)
 
reving higher than the 6400rpm limit without cams is pointless as you are past the thresh hold for optimum flow with stock cams. (hence why maximum power is at 5500rpm) if you ran 270deg + cams or some Tomei Poncams with power from 6900rpm upwords then fair enough. but running a stock engine you will not make any more power, you will just be able to stay in gear longer.
 
my ecu talk has a max revs reading and if i red line it, it says max revs were 6800

strange just checked and mine revved to 6962 rpm, i swear it only revved to 6800 when i had the mani on! wierd.
 
Ok, well bear in mind that the momentum of the engine will carry it on past the point where the ECU cuuts the fuel/spark - I'm not sure waht the maps look like on the ECU, but I would presume that they end at 6800 which is why the limit is ther?

Craig
 
Hey mates, just a head's up. The friend i know who has covered that hole in his dizzy, had to switch it recently cause it just failed. I recommend you think twice on covering that fifth hole inside the dizzy...
 
Logical - I really need to investigate more for my knowledge with the gear you sent me, Pete...

Craig
 

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