SPRAYED 01

iTrader: (22)

I'm retuning my car for the meth injection i added. Using hp tuners I have an afr error histogram to log the differeance between actual and comand afr in pe.

My comand and actual are very close as the car was professionally tuned before. When I add the Meth it obviously goes rich.

Do I just forget the error histogram and just get my afr correct by adjusting pe? Any advantage to adjusting ve instead?

How can I get my normal afr histogram fill in all cells?

denmah

iTrader: (2)

any of the ways you mentioned will work
just do whatever you feel comfortable with

Slowhawk

iTrader: (12)

I change the VE table. Found it to be more precise. Don't really know your options with HPT.

MUSTANGBRKR02

iTrader: (91)

Adjust VE not PE.

SPRAYED 01

iTrader: (22)

Mustangbrkr02,so what do you have you're pe set to? 1.0? I've read so many mixed things on this. Hpt says pe is were you do most of your wot tuning,so does the tuning school. I guess in the end it doesn't really matter as long as you get your afr correct.

Does any one know how to make The afr histogram or any histogram populate all cells?

BOTTLE ROCKET

iTrader: (4)

It's what you're comfortable with. I adjusted PE. It was much easier for me and it is dead on!!

SPRAYED 01

iTrader: (22)

What Im thinking (keep im mind im new to this) if I see an entire boost level or rpm range that's off adjust pe. If its more specific to an rpm or kpa I can make a more specific adjustement to ve. Can some one verify a formula in ve?

Actual afr divided by comand afr (14.7/pe enrichement multiplier) multiplied by number currently in ve table for that rpm&kpa equals new ve value.

Is that correct for tuning ve?

MUSTANGBRKR02

iTrader: (91)

I would have to look but I am in Afghan so I have to find my tune file but AFR is reached by setting lets say 14.7/1.25=11.76 or so AFR now you would use your VE table to achieve this using your AFR histograms. Do you have the BE (boost enrich) table activated?

SPRAYED 01

iTrader: (22)

I do have be but its copied from pe

n20kid

iTrader: (6)

You adjust the VE not the PE table.. That is called PE Table rating.. You need to adjust the proper Table and don't fudge a good tune up.. The PE table is a multiplier of Stoich.. Take a log, see what the AFR error is and adjust accordingly, you can lean it out some but unless you know what you are doing , i wouldn't suggest leaning it out to your non meth afr.. I do lean on the tuneup pretty hard at times but, the tuneup is spot on, afr, timing, iat modifier's etc.. Take it slowly..

SPRAYED 01

iTrader: (22)

If I adjust ve aren't i fudging up a good tune? Pe is just simple multiplier.

DropShipDave

I'm super new to tuning. So If I'm wrong don't hate on me lol. The logical thing to me would be to adjust the areas where you'd be in boost with the methanol on. So lets say you have a hobbs switch turning on your methanol at 5 psi.. Then you would want to adjust the parts of your VE table that are above the 135 kpa range. That way your car will run good still with the tune you had done and then be tuned for the methanol.

MUSTANGBRKR02

iTrader: (91)

No you would be adjusting your tune the right way to achieve the AFR that you are shooting for. The PE is what you are trying to achieve and the VE is how you get there.

SPRAYED 01

iTrader: (22)

Doesn't that all get thrown out when injecting the meth?, the ve table and pe,be were a set by the tuner before on pump fuel. Command and actual are very close pump fuel only. So making a calculated command afr in pe really doesn't mean anything any more oncev the meth gets sprayed.

So if I.know ve is set right for the setup why not just reduce wot in pe by taking away a % of fuel? In my mind it just seems like 2 ways to get to the same result. Why would hpt say right in the pe table that its used for wot fueling if its done in ve?

MUSTANGBRKR02

iTrader: (91)

The only thing that changes when injecting meth is you are adding more fuel externally. I still adjust the VE to compensate for this so the computer is commanding less fuel to achieve my desired AFR. If you mess with PE and your pump fails or you run out of meth etc you will now be commanding a very high AFR under WOT. Same argument can be made the other way but i prefer to do it this way and use my IAT to be a fail safe incase this happens.

BOTTLE ROCKET

iTrader: (4)

Actually its called "raping the PE table" much like it would be "raping the VE table" to get the desired results.

I cleaned up my VE table out of WOT. I use a progressive alky injection system that I set per recommendation (ramp up, etc) Then made WOT runs easing the PE leaner each run (started rich of course) until AFR was where I wanted it. It is dead on every time I log a run, so if it's not the correct way, it sure works pretty good.
Do whatever you're comfortable with and understand.