Guitarbuddy

After reading about the PMAS setup, I'm wondering how well it would work on my turbo truck. I'm looking for good street manners and capability to tow with the power there when I want it. If I went Mass air and got a maf sensor calibrated for larger injectors, would an A9L computer require further tuning?

My truck is stock except for a rear mount turbocharger running 6psi with a FMU and BTM. It runs good at full throttle but part throttle driveability is not good with this combo. I read where SStock said that the SD does not go into open loop until 2800 rpm or full throttle. With the turbo, boost can come in at low rpm if you load the engine.

93AZ-L

It would work great! I'm sure FMOS will chime in here... My truck is a "weekend street truck"(with a blower) and after running both SD and MA, the MA has better manners and is easier to tune... Especial with boost. Just my .02

fatoeknee

19's are fine for what you are runnin now. If you get a "calibrated" meter it will fool the computer to run the bigger injectors but the best way to upgrade injectors is to get it chipped/tuned

Guitarbuddy

So, a calibrated meter and injectors won't work as well? I read about a turbo kit for a 5.0 Mustang that included a calibrated meter and 42# injectors. The article said it ran good with no extra tuning.

Guitarbuddy

I guess what I'm wondering is if I went with the Mass air - would I need a tuner to dial in the extra fuel necessary for boost without running an fmu?

fatoeknee

so are you trying to ditch the FMU? the calibrated meter will work fine, it just wouldnt work as well as getting a tune is all that I'm trying to say

Guitarbuddy

Sorry, I'm full of dumb questions and here's another one: How do you know what size injectors to run?

lightngsvt

Your truck would run great with the PMAS kit. Although Im sure if you had a Tweecer and SSTocks help you could really improve your SD as well since it sounds like you have a very mild combo. I *believe* it is really only recommended to use the calibrated meter trick if you are using injectors under 42lbs, but Im sure 24 or 30's would be more than enough. Also you would have the choice of a blow through style meter if you wanted to go that route.

redlightningssf

If you go MA I would suggest a Big Air Maf 2400 or 2800, then you can tweec it or have a tuner dial it in to what ever injectors you decide to run. The other meters have to be sent out to be recalibrated to the injectors. You can ditch the FMU with 30# injectors or bigger, it all depends on how much boost and power your looking to make.
My Ford Mass Air is running 12 30# injectors, Big Air 2400, superchip and a BIG ***** blower.It runs great through out all RPM's.My truck is mainly driven on the street.

PMAS

And you can also get A pmas calibrated for say 50lb injectors and chip tune it for anything from 19's to 50's in the same way you would an SCT. You would be doing the exact same thing. You can call the PMAS maf calibrated for 50's a 2700 if you want cause it pegs at about 2700KG/HR.

Guitarbuddy

Thanks guys, my combo is mild right now and I will probably run it with the fmu for a while, but I know how it is when you must go faster! so I'm looking into all of the tuning options and this discussion really helps me to understand the pros and cons.

I hate to spend the $ for the PMAS kit and then still have to buy a tuning device or have chips made.

I've also looked into the SDS engine management system. It is plug and play based on speed density and comes with a map sensor that reads boost. You have to use a baumannator with it like the PMAS conversion. The company provides a base tune based on info you give them. You tune with a hand held game boy looking unit instead of a laptop. I know that Dynoman has had good results with this system on his rear mount turbo truck.

Then there is the tweecer. I guess I'm kind of intimidated by the learning curve and lack of support. The encouraging thing is there seems to be some experts here on this site willing to help.

lightningDan

did somebuddy say massair was better?



Danny

FMOS Racing

I get amused by the SCT hype on this subject all the time.

And no, I don't think you can run a turbo'ed truck with a calibrated meter and injectors and no additional tuning - I actually think you're headed for trouble using that method since the truck is already much heavier than the A9L expects and if you just use the "meter/injectors without tuning" method you really begin to run way outside of the A9L's stock tuning in terms of load calculation.

You will need to tweak the part throttle timing and fuel to make up for the additional load as well. It's much easier to do this on a mass air setup due to the way it measures "load" directly, but you'll have too much timing and inadequate fuel at part throttle of you don't do it.

There's always a boost retard and FMU, but don't know that you gain anything over a good tune in terms of cost.

svtpickemup

Last I heard is that SCT is still being babies about releasing their MAF Meter transfer functions, so I am not sure how well using a Tweecer with a SCT meter would work.

lightningDan

I was looking at one of their meters

Danny