[Bullitt5566]

I'm looking for a new MAF. I'm currently running a 90mm LMAF and a MAFia extender. I recently changed from S/C to N/A and back to S/C. I tune the car myself and loved the way the car drove N/A, and when I put the current LMAF/MAFia back on it ran super rich. I ended up removing the MAFia and leaning the MAF curve out 20% to get it to run right. I noticed that changing the injector slopes did virtually nothing A/F wise (although it should have), but changing the MAF curve did the trick. The MAFia requires changing the injector slopes which I want to avoid now. Long story to say that I'm looking for a MAF that will support 650 to 700 RWHP and not require scaling the injector data. I'm currently running a draw-though setup because the aftercooler setup doesn't have a straight section of pipe. Currently looking at the SCT Big Air 3000 or PMAS HPX in a 95mm housing. Anyone have experience with these or have another suggestion?

 

[03_Vortech_GT_Vert]

I have the HPX PMAS in a blow-through (3" housing); and a V3 S Vortech (Tial 50mm & FMIC) with no issues ... nice and smooth. Originally I was in a draw-through (from the factory sensor; not the PMAS); and I was getting erratic MAF counts. My tuner charged me a ton to tune it; but he didn't start from the tables on their site ... which I have a feeling would have cut the time and cost I'm sure.

 

[Bullitt5566]

I have to stay draw through because of the aftercooler piping, but I think the PMAS HPX will work in a draw through setup too. Plus it is an 05+ sensor version which should work better. BTW, my experience with the SCT PRP is too get injectors and MAF with known tuning data this will get you in the ballpark tuning wise. Then the tuner can just clean it up on the dyno. I just replaced my DEKA 60lb injectors with FRPP 60lb injectors because the DEKA injectors didn't have accurate data. That doesn't mean they are junk, just the tuning data isn't available. The LMAF and MAFia combo is the same. They'll work, but I shouldn't need an extender and skew the MTF 20%. Starting with Injectors and MAFs that have known tuning data is much easier.

 

[GBPackerFan]

My tuner uses SCT, he told me to buy an SCTBA5000 slot style MAF and DEKA Injectors. He had my car tuned in about 3 hours. It was easy.

I'm surprised to hear about the DEKA injectors. Were they high impendence? Again, my tuner told me to use those because he know them and has access to their data I guess.

 

[Bullitt5566]

Good info. Nothing wrong with the DEKA injectors, they were the correct high impedance EV1 injectors. I just had a hard time finding the correct tuning data for them. Your tuner probably had the data on hand. Do you run the BA5000 in a draw through? If so what housing is it in?

 

[GBPackerFan]

Good info. Nothing wrong with the DEKA injectors, they were the correct high impedance EV1 injectors. I just had a hard time finding the correct tuning data for them. Your tuner probably had the data on hand. Do you run the BA5000 in a draw through? If so what housing is it in?

Mine is a blow through in a 3in pipe. Yes, he has the data on the hand.

 

[98SnakeHorse]

VMP5000 blow thru in a 3" pipe. Drive-ability is very good. I'm assuming you could use these in a draw thru setup as well.

 

[GBPackerFan]

These VMP5000s, SCTBA5000s are always blow through on PD blowers. You shold def be able to use them in that application.

 

[Snorky]

my ev6 frpp injectors are made my Deka, I also use a sct ba5000, used to run blow thru. now I am turbod

 

[Bullitt5566]

I know the FRPP 60lb injectors are made by Siemens. I actually paid $400 for the tuning data and it worked. The car runs perfect wth them and I can sell the old ones off. I also contacted SCT today and they said the BA3000 needs to have the injectors scaled just like the MAFia. I've also learned that the injector slopes have a max value around #40 or so due to the clock rate of the EEC V. So I couldn't increase the injector size in SCT. Luckily I'll be scaling the injectors down by .76 for the MAF extender. I think for now I'll keep the 90MM LMAF and MAFia. Thanks for the help.

 

[sneaky98gt]

I'm surprised you're having any issues with the SD 60lb injectors. They're about the most popular injector out there for a somewhat modified 4.6.

There are several value files (I think 4) for them included in the SCT Pro Racer software, and who knows how many more a professional tuner might have. I just guess-and-checked each value file for mine, and naturally it was the last one, but everything has worked perfectly.

Not sure of exactly the reason, but the car runs and idles better on the 60s than it ever did with FRPP 39s, and that was with 2 different professional tuners and my tunes.

 

[Eagle2000GT]

Not sure of exactly the reason, but the car runs and idles better on the 60s than it ever did with FRPP 39s, and that was with 2 different professional tuners and my tunes.

I'm assuming that the 60s are a single spray. 39s are a double spray. They have a V spray pattern designed for two intake valves. I've posted this video before. In a single valve application they spray down the side walls.

 

[Bullitt5566]

Sneaky, That was exactly the problem I ran into, there are so many data files out there for the SD. I couldn't find one that worked. Getting the A/F correct was easy, but other parameters like battery offset have a huge effect on idle quality and you almost have to get that from the manufacturer.

 

[sneaky98gt]

I'm assuming that the 60s are a single spray. 39s are a double spray. They have a V spray pattern designed for two intake valves. I've posted this video before. In a single valve application they spray down the side walls.
why you should not use ford 39 in a chevy - YouTube

Interesting. Never heard that before. Certainly could be the reason.

I wonder how much difference that actually makes when air is flowing through the port. Even on our 2-valve heads, the injector isn't exactly firing onto the back of the exhaust valve; it's really firing at the opposite port wall (though at a decent angle), and I'd guess the incoming air charge is really what carries it into the cylinder, not it's inertia from being fired from the injector.

It's that theory / guess right there that I've done a lot of work with the injector timing in my tune. It makes an absolute incredible difference in idle and driveability. And when you get clever with it, you can gain some fuel mileage, too, especially with big cams. It's all about timing it such that you get a strong air charge to carry/mix the fuel well into the cylinder, but not too soon that good fuel goes right out the still-open exhaust valve.

Sneaky, That was exactly the problem I ran into, there are so many data files out there for the SD. I couldn't find one that worked. Getting the A/F correct was easy, but other parameters like battery offset have a huge effect on idle quality and you almost have to get that from the manufacturer.

That's the case with any injector though. Unless you got some knockoff injectors, one of those value files should have worked. They (the value files) were developed by SCT/Ford with data provided by SD, and therefore those values should be valid with actual SD injectors. If they're not, then I'd take a guess that something else is going on.