Rev Limiter..

[nathan.warren69]

Hi Guys,

I have come across something with my car, After a lot of reading and speaking to people it turns out that the rev limiter on my car is 7200rpm however the fuel cut off is 6200RPM, when I hit the fuel cut off it always feels like there is abit more to give so that extra 1000rpm could be very useful.

But is there anyway to increase my fuel cut off so I can reach the rev limiter?

I know that AJC can rev up to 7200RPM and he has pretty much exactly the same car as me.

Thanks

 

[frank]

on the pre-coilpack the limiter is a fuelcut nath, i would think yours would be the same

 

[nathan.warren69]

so is there anyway to raise it? and does that mean that the Fuel cut is my rev limiter?

 

[frank]

so is there anyway to raise it? and does that mean that the Fuel cut is my rev limiter?

only with a remap i guess mate, and dunno

 

[AJC]

frank, you think my bigger injectors and lower rail pressure would give me that extra 1k rpm, i just tried it using Torque and it says the same as my rev counter, 7100-7200 rpm, much to the annoyance of my neighbours i might add i know our ECU's can be a bit of an enigma being the C/P one

 

[frank]

frank, you think my bigger injectors and lower rail pressure would give me that extra 1k rpm, i just tried it using Torque and it says the same as my rev counter, 7400-7500 rpm, much to the annoyance of my neighbours i might add i know our ECU's can be a bit of an enigma being the C/P one

very few members have tweaked the coilpack models eh AJ, i dont think any car makers use a spark-cut limiter tho (else you get popping and backfire,s like the bee-r type ones eh) i think they all use fuelcut systems

 

[AJC]

Yeah that would make sense i guess, so bigger injectors, dumping more fuel in at a lower pressure would in theory raise the cut off, as it would be making more bang than the ECU was thinking it was, bit like a crude bleed valve on turbo cars? should have read 7100-7200rpm too

 

[nathan.warren69]

Ahh man, that's allot of effort to raise my rev limiter that litter bit, Are there any injectors that I can put in that don't require any modification, such as almera 1.6 one or something? and what sort of Gains would I get from increasing the injector size? also AJC do you have any pictures of your fuel rail and your fuel pressure regulator?

 

[frank]

AJ has the QG15/18 red injectors nath (211cc) and a bit less fuel pressure i believe

 

[nathan.warren69]

Arnt they the SR20 ones? and AJC was it a direct swap for your injectors? What sort of gains could I see from doing this

 

[AJC]

No the SR20 ones are squat fat things and have a different fitment to the rail, these are longer and thinner and a direct replacement. I got the reds really for when i get the turbo on. I noticed a very slight increase through the rev range, but more so at the top end, not much to write home about tbh, but it did make the response a bit better on gear change, and i run lower than normal pressure, as i said i think this may be why i get a higher rev range, i havent had time to test this yet tho. My reg is one of the 15quid universal ebay ones mate, very easy to fit, took me about 20 mins.

 

[nathan.warren69]

Tempted, Are they Expensive? and what's your fuel economy like compared to normal?

 

[nathan.warren69]

Do you have any pictures of the FPR fitted? and is it literally remove old connect up new? ITs a cheap mod that might make a difference to the way the car feels and maybe even better fuel economy

 

[frank]

these are the QG ones nath, yours will be the blue 164cc ones (and mine are the 292cc grey post 2000 SR ones)
and you have to remove the smaller O ring inside your stock reg so that the fuel runs straight through, then fit the aftermarket reg downstream

 

[AJC]

these are the QG ones nath, yours will be the blue 164cc ones (and mine are the 292cc grey post 2000 SR ones)
and you have to remove the smaller O ring inside your stock reg so that the fuel runs straight through, then fit the aftermarket reg downstream

As frank said, very straight forward to fit. I doubt you will get any better economy tho tbh with bigger injectors, unless you drop the pressure right down, then it becomes counter intuitive, as i only do 50-60 miles a week i aint all that bothered by economy, that said its prob only a matter of a few MPG if that i lose

 

[AJC]

I have a pic of it fitted but tbh, its not much to see, as you can see (ignore the 3 bar pressure, its on fast idle, normal pressure is 2.5 bar)