PDA

View Full Version : An example of a MAF to MAP conversion using MPI tuner (SMT6)



ChrisD
02-09-2005, 03:33 PM
*screenshots in thread*

The MPI tuner is almost identical to the SMT6, just modified in a few ways to work with the Mazdas. This thread is from a Mazda forum that I like to lurk on every once in a while. The application is very relevant to our cars and the AFM to MAP conversion that we talked about.

http://www.msprotege.com/forum/showthread.php?t=96397

Conrad_Turbo
02-09-2005, 04:26 PM
Chris, I just skimmed that page quickly since I am at work. So basically it mocks the AFM signal when using a MAP sensor? Did you notice any temperature compensation with the MAP setup?

So really all you need to do is record the AFM vs MAP signal in relation to rpm, then relate the MAP output to match the AFM output. That wouldn't be too difficult at all.

ChrisD
02-09-2005, 05:00 PM
Chris, I just skimmed that page quickly since I am at work. So basically it mocks the AFM signal when using a MAP sensor? Did you notice any temperature compensation with the MAP setup?

So really all you need to do is record the AFM vs MAP signal in relation to rpm, then relate the MAP output to match the AFM output. That wouldn't be too difficult at all.

Yep, just mocks the AFM signal. Pretty cool eh? I have no idea why people haven't tried this before.

Nope, there is nothing listed at all from this person about temp corrections. For the 3SGTE, I will be using a temp sensor pulled from a donor AFM (free from the junkyard), and inserting it right inside of the air filter/intake pipe area. Based on what the VPC does, I think this should work just fine.

Trance4c
02-09-2005, 05:56 PM
Alright.. so whos gunna do it first so we can get this happening?

ChrisD
02-09-2005, 06:12 PM
I'll be doing it as soon as the roads are a bit nicer and I get off my ass to install my rear diff mount. :wiggle:

Conrad_Turbo
02-09-2005, 08:42 PM
I'll be doing it as soon as the roads are a bit nicer and I get off my ass to install my rear diff mount. :wiggle:

If you have the capability of datalogging the two voltages over the whole rpm band I sure would like to take a stab at some calculations and see if I could get the MAP sensor to have an AFM output. If it's simple enough I am sure I could sell a AFM remover for around 100 bucks...really it's not rocket science.

I just don't like the fact that it doesn't have intake temperature compensation...although adding that makes things a lot harder since a lot more test runs have to be done to tweak the formulas.

nuclearhappines
02-09-2005, 09:49 PM
is not aware of temps
is not aware of changes in VE
requires constant tuning / minitoring .. or long term O2 trim corrections

go for it though ... the AFM-R showed a 30whp gain when they made it ... (was supposed to sell for 270 i think)

i'd like to see how this does

ChrisD
02-09-2005, 09:50 PM
Well, it will use the stock sensor to apply a correction. It just uses (base map) - [correction factor =f(intake temp, knock, water temp, etc)]

Oh and also, I can probably give you datalogs as well, not just a graphical display...but I'd also have the correction numbers after doing it myself. :)

Conrad_Turbo
02-10-2005, 03:51 AM
Well, it will use the stock sensor to apply a correction. It just uses (base map) - [correction factor =f(intake temp, knock, water temp, etc)]

Oh and also, I can probably give you datalogs as well, not just a graphical display...but I'd also have the correction numbers after doing it myself. :)

All I need is the #'s and I can do all the crunching. :D

mighty
02-12-2005, 02:45 AM
:wiggle: HEY i dont want to sound like a dumbass but can you explain to me what this mod is for and what gen. celica does it apply for!!!

Lagos
02-12-2005, 01:47 PM
cant we use the temp sensor from the 5sfe?

ChrisD
02-13-2005, 06:34 AM
:wiggle: HEY i dont want to sound like a dumbass but can you explain to me what this mod is for and what gen. celica does it apply for!!!

It's pretty generic actually...basically any of the cars equipped with a AFM (flapper door air meter device), or even the 7th gens that use a MAF sensor. We are basically talking about readjusting the maps so that we can run without this big restriction, and tune solely by manifold pressure. I think the 2nd gens all the way to the 6th gens, depending on models, used the AFM. Some used MAP or MAF's.


cant we use the temp sensor from the 5sfe?

I just went to the junk yard and pulled a temp sensor directly out of an AFM from a 4th gen GTS. I'm not sure what sensor the 5sfe uses...

Lagos
02-13-2005, 06:26 PM
the 5sfe has a basic 2 wire sensor that sits in your intake tubing. seeing as how the 5sfe is a map based motor, it should be perfect for what you are trying to do.

ChrisD
02-13-2005, 09:13 PM
Yeah probably the exact same thing as what sits in the AFM of other celicas. 5SFE's are too hard to find in junkyards though, so pulling one out of a NA celica will work just fine. Also, it will for sure be the same signal that the ECU is looking for.

Weasy2k
02-18-2005, 01:59 AM
Yea wire the air temp sensor into the eng temp input on the SMT6 and you can map it off that too :) then you got air temp modification as well.

irishtwincam
02-25-2005, 02:25 PM
http://www.my-acoustic.com/Car/AFM/Replace_AFM_by_MAP.htm

This is a good article on the mechanical side of things.

ChrisD
02-25-2005, 05:03 PM
Thats a good read. :)

Weasy2k
02-25-2005, 05:10 PM
Yea that is a good read thanks!