merchauser

jim, any ideas on how could that be accomplished?

FredR

Nick,

Doubtless you will be aware but the problem with these systems is that when the throttle is opened there is a temporary leaning out of the mix. The system has a preset map that enriches the first few pulses when the MAF detects an increase of load but this of course is all feedback control and that takes a finite element of response time to implement. I have no idea how your alpha N system deals with this phenomena but presumably it senses the throttle is opening and implements a solution along the same lines. Low to mid rage load cells are obviously more problematic as the air flow rate of change is far greater.

I suppose the ultimate solution to the problem would be to have a brain sensor connected that detects lunatic intent and starts to chuck a bit more fuel in before one's foot hits the pedal!

Thus making the cells a bit richer on the base tune [cars with no O2 sensor] helps pick up somewhat but it is not something one wants all the time as fuel economy then hurts. Messing around with the transient enrichment mapping presumably helps but how much?

Speedtoys

Buy a spare setup on sale, study it..start 3D printing.

There are likely aftermarket solutions that you would then have to adapt to the 928 TB...

One could modify/lengthen the throw on the quadrant so there is a longer lever arm to the throttle body from it (or a shorter arm from the pedal) to make it move quicker.

Either is a cut and a weld away from achieving that.



Of course, ill wait for someone else to say the same thing so it sticks.

Wisconsin Joe

I don't think that it would be a direct replacement, but there is a replacement cam for the 944. Changes the way the throttle opens.

Supposed to be a very nice improvement in throttle response, without any real change in engine output. Its all in the pedal 'feel'.

merchauser

that's very interesting! is the 944 set up similar? anyone know more about this?? who sells the replacement?

Speedtoys

https://www.google.com/search?q=porsche+944+throttle+cam+mod&oq=porche+944+throttle+cam&aqs=chr ome.2.69i57j0l3.11400j1j7&sourceid=chrome&ie=UTF-8

Short answer, it is in no way the same as a 928 S4 throttle, the 944 is much simpler.

Cant one just push the pedal more for free?

James Bailey

Perhaps step one is to be SURE that the throttle is actually opening fully with the pedal all the way down

merchauser

great advice, and I think very often overlooked. I had that problem a few months back and has been corrected.

Strosek Ultra

Paul, a step further is to install a larger throttle valve and port the throttle housing.
Åke
https://rennlist.com/forums/928-foru...ughout-30.html

Wisconsin Joe

Honestly don't know.

I've got a 944, and read the 944 board. I've heard it mentioned, but have never seen a pic or link to supplier.

And JB (duh) Speedtoys is correct, the 944 throttle setup is way simpler than the 928.

V2Rocket

944 throttle cam originally was Weltmeister and can be bought on Pelican, Paragon, 944online, Rennbay...also only944 makes their own too.

But I don't think it'll work on the 928 TB as the method of attaching the cam is totally different.

merchauser

it is VERY different and there is no doubt it will not work. not even sure it uses the same principle. on the 928, the pulley seems to only function
as a guide?. on the 944 is appears to act as a cam

is there any way to modify the 928 pulley and/or linkage to get a better pedal response? that XK8 I mentioned in an earlier post was not fun,
and the response was too twitchy. but somewhere in between might be nice: like goldilocks porridge??
surprised this hasn't been addressed before....or perhaps it has??