[DrKevM5]

So I had my first experience driving in anger with the Dinan S4 software at Watkins Glen today and uncovered an unsettling glitch. The rev limiter would engage at 6k rpms, well below the stock redline! After calling my installer, they contacted Dinan, and they advised me to change the mapping to S3. This decreases output a tad but allows access to the entire rev band, which made the track experience much more enjoyable. I?m hoping that Dinan Engineering can chime in to explain why the safeguard in S4 wont allow full access of horsepower.

[SeanWRT]

So it happens only when you push really hard like on track? Does S4 recover to 7k rpm after cooling down a little bit?

Does it have anything to do with you being a MT as I remember?

At high RPMs, M2 ECU on stock tune is easily upset and thus responds too conservatively (dumping fuel, lowering boost, pulling timing etc).

[DrKevM5]

Had nothing to do with temps. Occurred during warmups at the first lap. Not sure why having a manual makes a difference.

[mike@x-ph.com]

Did you call Dinan direct and ask them?

[GMWNashville]

Having the same issue with a customer car. Seems like the car is running out of fuel accoriding to them...Can't datalog since DME data isnt accurate due to piggy back...

[DrKevM5]

Yeah, they told me the same thing about fuel pump couldn't handle the higher boost levels. Thinking of fitting this. http://www.fuel-it.biz/f-series-n55-...-lpfp-upgrade/.

[ZM2]

Originally Posted by DrKevM5

Yeah, they told me the same thing about fuel pump couldn't handle the higher boost levels. Thinking of fitting this. http://www.fuel-it.biz/f-series-n55-...-lpfp-upgrade/.

This sucks to hear. My Stage 1 works fine on track. If Stage 4 doesn’t, then I’ll skip that upgrade. Do you feel much difference b/n Stage 1 & Stage 3?

Also, I thought the fueling issues with higher boost/HP was with the HPFP, not the LPFP.

[ZM2]

Any updates from Dinan?

[GMWNashville]

May want to go with a flash tune...

[ZM2]

Originally Posted by GMWNashville

May want to go with a flash tune...

We all know a flash tune is the way to go, but until the flash tuners step up and provide a Dinan warranty, it’s a no go until I get 50K on the clock.

[AndrewC1989]

Originally Posted by DrKevM5

Yeah, they told me the same thing about fuel pump couldn't handle the higher boost levels. Thinking of fitting this. http://www.fuel-it.biz/f-series-n55-...-lpfp-upgrade/.

Cheaper alternative:

https://www.dinancars.com/product/r4...ries&mid=1243/

[ZM2]

Originally Posted by andrewc89

Cheaper alternative:

https://www.dinancars.com/product/r4...ries&mid=1243/

As I’ve stated in several posts, I don’t think the LPFP is the issue. It’s the HPFP.
I did this Dinan upgrade and it helped with fuel pick up issues, not fuel feed issues under higher boost.

I’m not an expert, I’ve just learned by researching everyone else’s posts.

[DrKevM5]

Originally Posted by andrewc89

Cheaper alternative:

https://www.dinancars.com/product/r4...ries&mid=1243/

Did the Dinan fuel mod when I had the Stage 4 installed. The problem is it needs higher flow.

[AndrewC1989]

Originally Posted by DrKevM5

Did the Dinan fuel mod when I had the Stage 4 installed. The problem is it needs higher flow.

[ZM2]

Originally Posted by DrKevM5

Did the Dinan fuel mod when I had the Stage 4 installed. The problem is it needs higher flow.

Did Dinan have any specific fixes to remedy the issue you noticed in track, besides turning down the power?

[SeanWRT]

DrKevM5, if issue occurs during warming up, how is fuel pump going to fix that? Either high or low pressure fuel pump fails only under high load, just in different ways.

[DrKevM5]

My warmups are a tad aggressive

[ZM2]

Originally Posted by DrKevM5

My warmups are a tad aggressive

Have you been back on track since, and is there a noticeable power change bn Stage 3 and 4? I’m curious which is faster, Stage 3 to redline or Stage 4 to 6k.