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king D
03-19-2003, 19:54
just wondering if the predator raises the engine rev limiter,and also what chips are out there other than a reflash that will raise the engine rpm limit.thanks for the time ...jess

schnier
03-20-2003, 05:42
RPM is still goverened at 3200 rpm. It could be out in the future. It raises top speed to 110 mph on the 2001, and 125 mph on the 2002,2003.

Colorado Kid
03-20-2003, 11:42
Of course the 125 MPH on '02s and '03s is theoretical, because they run into the unchanged RPM limit at...you guessed it...110 MPH.


OK, maybe 115 MPH at 3400 RPM, but not 125 MPH.

c5dura
03-20-2003, 11:53
I don't think it is possible to raise the rev limiter without a PCM re-programming.

A 'chip' can't change the pre-set limit within the PCM. If the chip 'changes' the RPM that the PCM sees, you would likely run into all kinds of other problems with fuel curves, timing and transmission shift points.

RWTD
04-02-2003, 14:33
The Predator does raise the rev limit of the vehicle, by approx. 200 to 400 rpms. FWIW, the pcm is still programmed to deliver after the factory preset rpm.

Has anyone with an Automatic not been able to go higher than the factory limiter? I know some 6-speed owners have.

Sincerely...

Kennedy
04-02-2003, 15:08
I have not seen the RPM cross approx 3250 which is about stock RPM. I would have to check against stock to be absolutely certain, but IIRC, the last time I talked with Johan he said it did not increase the RPM.

king D
04-02-2003, 19:37
runnin witht the devil if you are willing to garantee that 200 to 400 rpm rev limit increase send me a box but if the rpms dont climb i want to send it back.let me know.......jess

RWTD
04-03-2003, 00:26
> I have not seen the RPM cross approx 3250
> which is about stock RPM. I would have to
> check against stock to be absolutely certain,
> but IIRC, the last time I talked with Johan he
> said it did not increase the RPM.

Wow, okay, I'll bring this up to him again tomorrow, then. I have not personally tested the raised rpms myself, but I'm almost positive that someone on here tested it out on their 6-speed and found it raised by approx. 400 rpms (if you're out there, please speak up).

My understanding *was* ;) that the rev limiter is raised once you modify the speed limiter. Anyhoo, thanks for the post, as I appreciate it John.

Take care,

James

Kennedy
04-03-2003, 08:36
When playing at the 350+RWHP levels, you will find that the turbo "crosses over" from a positive pressure ratio to a negative pressure ratio at about 2000-2100 RPM. By 3,000 RPM, it will be a negative 1.5. In other words, 30psi and 45 psi back pressure.

This is why peak HP rpm tends to drop as HP levels increase...

While this is not the absolute gospel, it has been my observation.

king D
04-03-2003, 18:07
i have seen in test with a ppe reflash that with the waste gate blocked off and the rpms over 3500 that boost levels will push 40psi and also give one whole helluva lot more kick in the arse,not the gospel just what i have seen ,also once again does anyone know if the rpms are raised on anything other than a reflah,thanks jess

a64pilot
04-04-2003, 07:24
Guy's
It's a diesel, a 4-stroke diesel at that. It's not a 2 stroke *** race bike. Diesels are good at building low end grunt. There are many good reasons that our rpm limit (under fuel) is so low. It's not a structual limit. It has to do with where the eng makes good power at. Fuel burns at a set rate, IMHO this is why pilot inj. goes off at a set RPM. Turning up the RPM decreases the available time that fuel has to burn so you have to increase timing which raise cyl pressure which may cause premature head gasket failure etc.
Be wary of too much boost or too much RPM etc. How much is too much? I have my own opinion, but since it is not based on empirical evidence I won't voice it