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Re: VT GTS Memcal

Posted: Fri Sep 10, 2010 9:06 pm
by benk
The max you can set the Rev limit is 6350 in the VT CFZF bin and the cam is still pulling, when you drive it you are on the rev limit before you know it :shock: and the engine has been built to be able to handle more rpm so we might as well use it :twisted:
I still runs the standard intake and air box from the twin throttle body back and the intake vacume realy starts to climb at 6250.

Re: VT GTS Memcal

Posted: Fri Sep 10, 2010 10:10 pm
by Holden202T
ahh right, i didn't know there was a limit to the rev limit number .... another reason to not have a maf tune :P

Re: VT GTS Memcal

Posted: Sat Sep 11, 2010 12:06 pm
by benk
Has anyone done a mafless tune or know where I can find some info on them?

Re: VT GTS Memcal

Posted: Sat Sep 11, 2010 2:53 pm
by Jayme
it might be easier to convert back to a VR/VS style map based ecu, then you wont have the rev limit problem and it will be fully map based. you wont be losing any outright power by ditching the sequential fuelling

Re: VT GTS Memcal

Posted: Sat Sep 11, 2010 4:33 pm
by VL400
Could be patching time for the rev limit :( It can be disabled entirely very easily but its not a long term solution. One way I think that may be possible is to make an RPM term that is RPM/50 instead of RPM/25. You then get a max rev limit of 12,750RPM but only 50RPM resolution.

A VR/VS PCM will need some playing with to get the dash working again too. Am not sure if the kalmaker mafless tunes have RPM limits of > 6375RPM so would need to check that out if going down that road.

Re: VT GTS Memcal

Posted: Sun Sep 12, 2010 6:41 am
by benk
VL400 wrote:Could be patching time for the rev limit :(
I don't want to bypass the rev limiter completely as I still want some protection on the engine
VL400 wrote:One way I think that may be possible is to make an RPM term that is RPM/50 instead of RPM/25. You then get a max rev limit of 12,750RPM but only 50RPM resolution.
Not sure where even to start with to do this :?

Re: VT GTS Memcal

Posted: Sun Sep 12, 2010 7:35 am
by yoda69
Currently the RPM limit is $FF (255) x $19(25) = 6375RPM.
From what I've read, Kalmakere set theirs at 8000RPM which equates to 8000/255 = 31.2

If it was set to 30, this would give a maximum RPM of 30 x 255 = 7650RPM.
If it was set to 35, this would give a maximum RPM of 35 x 255 = 8925RPM.
If it was set to 40, this would give a maximum RPM of 40 x 255 = 10200RPM.

I would have thought 30 would have been enough for most people but 35 should cover nearly all (non motorbike) type applications, and still give reasonable resolution.

yoda69

Re: VT GTS Memcal

Posted: Sun Sep 12, 2010 8:09 pm
by VL400
Will look at making an RPM/32 term for rev limit lookups, 32 is easier for binary math and gives you a max of 8160RPM which should be ample. Not 100% sure if its possible yet but will check it out.

Re: VT GTS Memcal

Posted: Sun Sep 12, 2010 8:10 pm
by benk
Is it hard or possible to change the multiplier in stock code to get the higher RPM?
question answered above :D

Re: VT GTS Memcal

Posted: Mon Sep 13, 2010 10:13 am
by VL400
The easiest way for this to work will be to just use the RPM term and have a single 16bit RPM limit and return fuel - max of 65k RPM with 1RPM resolution (although the RPM calc is not that accurate). It wont have the different limits for Drive/P/N/Rev but the bin thats going to be modded is for a manual anyway. Will email you a copy to test later on.