hally

http://www.splitsec.com/products/psc1/PSC1004.htm

In terms of MAF piggybacks this seems quite holistic in terms of emulating an AFM. It encorporates temp and barometric pressure compensation into the load signal sent to the DME while switching off the DME temp compensation (by sending a constant temp value, this way there is no doubling up of temp compensation).
If you emulated the stock AFM signal (so that timing is aligned) and just extended it up top to utilize the full 5v range, this would seem like a pretty clean solution when paired with an AFM chip. That would extend the measurable range, to what hp maybe someone could chime in?

Downside would be the loss of other (non-load related) temp dependant DME functionality, (i read somewhere that timing is retarded when conditions are very hot for example, + Cold start enrichment?). So we are trading doubling up on temp compensation v's keeping this functionality..If only the piggy back could be configured to apply the reverse temp compensation, so the AFM could put it back in and it would be in balance.

jimbo1111

They work very good. If your interested in trying it out I am selling mine. Along with 52lb injectors. $400 for both.

Mike Murcia

I have the PSC1-003 for my APE MAF, but have not installed it yet. Jimbo, what version of the PSC1 are you using with your Vitesse MAF?

hally

pming u jimbo

jimbo1111

The 004.^^^^ The 003 and 4 are the same except for a barometric sensor that compensates for elevation changes. Gives a better idle on low bar days/colder whether. It starts to add fuel at over 1000 ft elevation. This helps alot with afm chips and maf. The VT chip doesn't need it. I have driven to over 900 ft and had no ill effects. This was verified with a wideband. I like the unit a lot. I think I'm going to get the 003. I have a house in the hills a few hours out of the city at 2000 ft. I don't want this to effect my a/f. When I drive up. It may or may not. I just don't want to risk it.

Mike Murcia

Maybe I misunderstood you. You are getting a 003 (without the barometric pressure sensor) because you don't want an elevation change to effect your A/F? How would this help? Wouldn't the 004 (with the barometric sensor) be the one you want to use?

I've got MAF chips, but I was going to try to use the PSC1-003 to tweak my A/F for a bigger turbo and 52Lb injectors. I'm glad to see that there are people using these because there is not much info in the archives.

hally

Hey Jimbo, what about the stock altitude compensation in the DME - how do you disable this. From memory i believe it removes a fixed percentage of fuel above a certain altitude.

jimbo1111

When using afm chips with maf. The 004 is the piggy to use. I never had any of the problems with this piggyback that I had with the arc 2. The arc 2 had idle problems because colder days would add more fuel. The hotwire thinks there is more air than there really is on colder days. warm days would do the opposite. That's why a barometer was incorporated into this unit. It works perfect. The Maf chips should be fine without the barometric sensor.

hally

Howdy Mike looks like i will be your PSC1 buddy once i work out what i'm doing 4 a MAF sensor and jpipe. I'll be busy first fine tuning my on-chip maps for the 52 pounders, 1 step at a time. One way to deal with the injectors is to edit the FQS table on chip this is what I plan to do first, then just fine tune with the piggy. Danno's chips have a 55#, 65, 75 entries but no 52#, so will have to overwrite one of them. this way you can switch b/w stock and new injectors with the FQS, could be handy.

Mike Murcia

Hi Hally. So you make your own chips Hally? I'll be buddies with anyone that can do this! Are you going to make some MAF chips, or just tweak the MAF signal for the MAF chips to read? I also have Guru chips, but mine were mapped without a FQS option for larger injectors. That's why I was looking to get a way to adjust the MAF signal to compensate. I'm not yet sure if the PSC1 will allow me to adjust enough, but the bigger turbo should help use up some of that fuel.

hally

yep i got a pocket programmer 2 from xtronics - so far i have just modified the WOT fuel map to get a nice a/f curve. My part throttle maps seem pretty good out of the box, so i havn't felt compelled to play with that yet. Not planning initially to venture into making a MAF chip, see how i go with the simpler solution first (using jimbos psc1). i'd be happy to mod you chip for different injector sizes, logistically it could be trickey with me hanging out in the sothern hemisphere though. its just a sequence of 4 bytes one for each FQS position each byte contains a scaling factor for the injector duty cycle, so you can set them up for different injectors sizes (like guru), fuel pressures, or different levels of enrichment like the stock chips. PM me anyhow if u want to try that path.