vinuneuro

ATTS depends on the engine ecu for only a few inputs: ignition switch, injector, map, engine speed signal. Would it feasible to split those signals from the ecu's harness to the atts harness? This should allow the atts control unit to get all the engine inputs it needs. Thoughts?

98vtec

i wish i could help but getting a unit that is OBDII running with a unit that is OBDI is no easy task, in my view atleast.

contact blundar here on HT or make a post on http://www.pgmfi.org and see what they say.

report back if they have anything to say.

SHPrelude00

depends on your HP goals because of ATTS shutting off around 250hp... ATTS is a bad *** system WHEN it works... the whole idea is to send 80% more torque to the outside wheel during a turn... if you disabled the unit all together then it would be operating as an open-diff all the time... just kinda depends on if you plan to exceed HP it can handle...

I honestly would like to know how/if it's possible to make the ATTS unit stronger and does anyone know exactly wat it is that fails/turn off? I know theres like 3 or 4 oil pressure sensors in the unit, maybe they just can't handle the new pressure? curious

98vtec

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SHPrelude00 &raquo;</TD></TR><TR><TD CLASS="quote">depends on your HP goals because of ATTS shutting off around 250hp... ATTS is a bad *** system WHEN it works... the whole idea is to send 80% more torque to the outside wheel during a turn... if you disabled the unit all together then it would be operating as an open-diff all the time... just kinda depends on if you plan to exceed HP it can handle...

I honestly would like to know how/if it's possible to make the ATTS unit stronger and does anyone know exactly wat it is that fails/turn off? I know theres like 3 or 4 oil pressure sensors in the unit, maybe they just can't handle the new pressure? curious</TD></TR></TABLE>

can we please stop referring to it stopping at 250hp? its not even a horsepower related issue although (in a way) hp and torque are related. no one even knows for sure what amount of torque will shut it down.

If you upgrade the clutches in the unit, you could possibly make it handle more torque. But find a company that is willing to do that and not produce many sets and you'll be lucky.

vinuneuro

Thanks Blake. I'll try there.

98vtec

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vinuneuro &raquo;</TD></TR><TR><TD CLASS="quote">Thanks Blake. I'll try there.

I'm only doing a mild NA all oem build, so no concerns about exceeding the unit's limits.</TD></TR></TABLE>

can you find a pinout of the ATTS unit computer harness?

SHPrelude00

sorry geez... i was going of wat was last said about it here, oops...but you know like i know a high hp prelude with ATTS would prolly be a handling beast...

98vtec

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SHPrelude00 &raquo;</TD></TR><TR><TD CLASS="quote">sorry geez... i was going of wat was last said about it here, oops...but you know like i know a high hp prelude with ATTS would prolly be a handling beast... </TD></TR></TABLE>
until you touched the throttle and spin out

vinuneuro

mgags7

Blake this isn't as hard as you guys think. Great idea Vig

All you will need to do is run the wires over there, the only thing I forsee problems with is #9 pin. FI-TX. Fuel injection transmission, I don't know where you're gonna get that with obd1.

I just noticed #19 is the same thing, but RX means recieving. I don't know what to say about that one either. The rest of it should be as simple as plug and play.

Can someone describe how the atts ecu hooks to the car's ecu? or is it part of it? How does this setup work?

vinuneuro

98vtec

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mgags7 &raquo;</TD></TR><TR><TD CLASS="quote">Blake this isn't as hard as you guys think. Great idea Vig

All you will need to do is run the wires over there, the only thing I forsee problems with is #9 pin. FI-TX. Fuel injection transmission, I don't know where you're gonna get that with obd1.

I just noticed #19 is the same thing, but RX means recieving. I don't know what to say about that one either. The rest of it should be as simple as plug and play.

Can someone describe how the atts ecu hooks to the car's ecu? or is it part of it? How does this setup work?</TD></TR></TABLE>

i'd like to see you do it then

mgags7

Oh don't worry blake, me and vig are all over this.

We're gonna sell clip in jumper harnesses under the name "Thank you bitches, inc."

PirateMcFred

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 98vtec &raquo;</TD></TR><TR><TD CLASS="quote">
can we please stop referring to it stopping at 250hp? its not even a horsepower related issue although (in a way) hp and torque are related. no one even knows for sure what amount of torque will shut it down.

If you upgrade the clutches in the unit, you could possibly make it handle more torque. But find a company that is willing to do that and not produce many sets and you'll be lucky.</TD></TR></TABLE>

Yes, torque is what counts with the clutches, not horsepower. I also don't think there's a set limit of torque that the clutches fail at either. It probably deopends on the condition of the fluid, the type of fluid, condition of the clutches, surface finish of the pressure plates, oil pressure etc.

The ATTS light probably is turned on when internal sensors notice the clutches slipping. If you have a high milage system then it's probably less likely to withstand as much torque as a newer system.

If the ATTS unit's clutches are engaged by oil pressure then you can increase the torque capacity shimming the oil pressure regulator spring(s). More spring pressure, more oil pressure, more friction, the ATTS unit can take more torque. The only issue is that you might end up with too much oil pressure to open the solenoids that engage the clutch pack(s) if you shim the springs too much. If you're road racing and the solenoids are constantly being used they could eventually overheat too.

Taken from Revi's ATTS thread: Shim these for more pressure:


Again this is just theory. I am not sure I have the way it functions right in my mind and if it did work I am not sure how to test its effectiveness. I you knew that one ATF fluid had a lower coefficient of friction that might help too. But it's a lot of work in comparison to a standard auto torque biasing differential.

vinuneuro

I don't think increasing pressure mechanically like that would work. The linear solenoid valve regulates the pressure to left and right solenoids. So the linear solenoid would either be made to compensate if higher pressure was seen at the oil pressure sensor (which is after the linear solenoid and r/l solenoids), or the atts ecu would just all together shut the system down with linear solenoid DTC if it wasn't able to control the pressure well enough.

vinuneuro

Back on topic: as far as i can tell, the atts control unit only relies on the ecu for the pmfi-comm lines (tx/rx) and voltage reference (0v or 5v). Everything else seems to come directly off the ecu or abs harnesses.

Fastkill

this would be so damn nice if it could work. All the sh owners would finally be relieved of their handicap tune... I wish there was enough interest in the idea a long time ago to really get something in the works.