Lizard928

As to the MAP, it isnt a huge issue to get a line properly to it with no delay.
If you use a massive line then you will have issues, but my vacuum line was about 1.5' and I had zero latency.

Mongo

Where did you connect your MAP at???

Lizard928

MAP sensor was built into the case.
So engine bay down to the fuse panel. But the hose was alittle long

Mongo

Not sure I understand what you mean built into the case...

I was wondering what would be the best area to run a vacuum line to the MAP from the intake, i.e that 5-way splitter in the back of the engine.

dprantl

Yes that would probably be the best place. I wouldn't worry so much about the length of the line as long as you keep the diameter stock. Remember that the early 32-valve engines have a line from there down to the EZF box in the passenger footwell because that brain actually has a built-in MAP sensor.

Dan
'91 928GT S/C 475hp/460lb.ft

PorKen

As well the 951's KLR knock box, which is also inside the car. (Very similar to an EZF.)

Speaking of which - Colin - you need to help me figure out turbo sizing for a mid turbo for my '85. I'm hot to reprogram a KLR box for it, if only so I can use the 951 tach.

Mongo

Does that include the '87 928 engine?

PorKen

'87-up has EZK ignition, which uses a processed LH load output, MAF+RPM, instead of a MAP sensor, so no vacuum line.

Mongo

I thought so.... I hope Carl is seeing all this and can clarify this up.



Holy Crap! I just remembered that there is a nozzle on either the top or bottom of my throttle body that wasn't used. Why not use one of those for the MAP?

BC

It would matter if it was at the top or bottom. You need manifold reference - meaning NOT before the TB.

Mongo

This one was after. Now that I think about it, it was open on the bottom. That was the charcoal cannister one I believe. I used one of the top 2 nozzles for it after the intake R&R.

Carl Fausett

Sorry I did not answer sooner, I did not see this thread had "come alive" again.

You might also be interested in this thread where you can see the Electromotive system installed on the 16v race car. This is the one that I am tuning now: https://rennlist.com/forums/928-foru...prototype.html

As to your research - read up more on the TecGT system instead of the Tec3 system. I am using the TecGT system instead of the Tec3 because I do not need the capability to run 8 EGT sensors and full sequential injector timing.
It would be nice for the race car, but not what my customers need. Too complex. So I am focusing on the TecGT system, simpler install, simpler tuning.

As to your questions: the TecGT system will allow you to continue to use your MAF sensor if you must, but most folks wont. A lotof new cars have done away with them.... it's very 90's. A MAP sensor and a TPS (throttle Position Sensor) does the trick now...

As to temp sensors: for water, we are connecting to and using the stock coolant sensors int he water bridge. As to air temp, you want your sensor in the central plenum or close to it. Your comment about welding to the magnesium alloy is valid - you dont want to do that.

You could mount the air temp sensor in the air box the way Porsche did in '85-'86 and avoid the whole problem. Or in the tubing just before the throttle body.
Or drill and tap a thick wall of the manifiold itself and seal it with JB Weld on the threads (it makes a darn good thread sealant).

Carl Fausett

One more thing: as to where to pull the plenum signal line for the MAP.

Avoid high-velocity areas and try to locate an air-flow "dead spot". These are more ideal for placement of the MAP signal port. Middle of a high speed air stream - not so good for measuring pressure. Dead air spot outside of any direct air stream, center of the plenum or corner of the plenum (away from the direct path of an individual runner) - better.

Mongo

I didn't realize that TecGT was so much more simpler than the Tec3 setup. Impressive. That probably attracted me even more to buying this setup.

What would be a good example of where there is a low/no-velocity location on the S4/GT intake manifold, or where would you recommend the MAP line at? I would prefer to use a vacuum location already on the intake manifold and no modifications.

I am definitely taking it into consideration of mounting the IAT on the bottom side of the airbox.

Bill51sdr

The new ignition system wiring would not pass the CA visual inspection if the smog tech knows what he is doing. Doesn't matter if the emissions are clean, the very fact that you can alter the ignition timing and pulse rate is a problem. I've seen references to "off-road use only" so it's pretty certain this thing is not CARB approved. You could try to "hide" the system, but how do you disguise the distributor caps with no plug wires in them?