EMan 928

when do the chips go on sale?

BC

OKay, now onto the airbox? Or headers?

IcemanG17

interesting data......

The more I learn about 32V INTERFERENCE engines is the more I HATE them..... I blew up two 32V engines....1 16V engine due to excessive oil leaks and walmart oil.....(racing conditions)..... Since then I have ran two 928's....one is OVER 125 hours on track....mine is about 22 hours.... both 16V.....

Yes my opinion is biased by my personal experience....which has seen precisely two blown 16V engines.....one was due to excessive oil leaks + walmart oil smoking the 2-6 rod bearing (yes S4 style oil pan)..... The other had the benefit of the improved "OB" oil pan, but electrical problems caused it to be extremely overheated which smoked the rings.....not really a design fault, a driver fault.... :>)

I am not an engineer.....I don't build engines....I merely race them....my opinion is just what works for me....as in IF I can race it for hours and hours per day with minimal issues I consider it good....

Hilton

Very nice graphs! Getting on the torque below 3k rpms will be nice.

I'm at about 1500km's since the fitting the new timing belt on my '87 - so its almost time to check belt tension and retard the cam timing while I'm in there.

Is it safe to assume your chips will work just fine on non-cat coding plug cars too?

FredR

Ken,

How do you manage to defy physics? You have more on top end end, fine-more timing, cam retard etc but how do you get the low end torque chuncks "free and gratis" as well?

I have played around a little on cam timing with 32VR and found that indeed a bit of retard seems to make the motor a bit sweeter [I have the GTS inlet cams fitted]. I have not tried your degree of retard but guess what...? Come Sept/Oct when the inferno cools down I will. I find that my motor [1990 S4] seems to want low 12's to avoid chronic knocking on our 95 [RON?] witch ****, but I have managed to get a stock of STP octane booster- have not tried putting stock advance back in since getting this stuff. At the moment I have capped advance to 27 degrees on top end/full load.

Not sure if you want to share [quite understand if you do not] - but what octane/advance combo are you currently using?

Great work whatever it is you are doing there- the dyno don't lie [unless you use a "Wishful Think" one- ho ho].

It would be nice to see a before and after with the EIS inlet system fitted before you finish.

Yesterday I unwittingly ran the car with my stock EZ fitted [swapped out my tuned LH PEMS into the spare LH unit I have a few weeks ago and forgot to put back]. I wondered why the motor felt "tired" mid range!

Regards

Fred

Speedtoys

Still need a Roger EIS system Ken?

Email me.

FredR

Jeff,

Crikey- just read your signature- you have a 4 inch exhaust? That's an industrial chimney stack!

Regards

Fred

Speedtoys

It's not bad....

PorKen

Next up is finer fuel tuning. It may not raise the peaks, but it will make it more consistent.
I wanted to dyno to be sure the cam timing was doing what my logs were showing before I spent a bunch of time on it.

The scaling used on the EZ still confuses me. (The LH wasn't too difficult, surprisingly.)
For WOT, I am using the knock table scaling, which is a little better than the cruise scale, but not perfect.
There are probably some gains here and there to be had with more detailed EZ tuning.
I have had to retard in broader strokes than I would like because I can't get at the offending rpm with the rpm columns available.

All in all, I'm very happy the cam retard worked so well.
One extra benefit, I'm able to run 4° blanket advance over the stock cruise map, which makes regular driving a lot more fun.

My goal is to strip out all the coding plug programming and supply individual chipsets.
I'm using the extra coding maps for extended WOT maps on both the LH and the EZ, so they are already unused.

I'm also wanting all those wasted inputs into the ECUs for extra functions (as yet undefined).

I'd like to use the non-cat adjustment (1K ohm) pot to allow some user adjustability and/or an air temp input.

PorKen

S4s don't like to be dynoed over and over!

There is no use doing more than two runs at a time - the second run will always be the highest.

Turn off the engine, turn the key back on, unplug the lower rad fan sensor, let the engine cool for at least 5 minutes before doing another set.



It's frustrating, compared to my S3 chips which react to air and water temps.
Dyno all day and the graphs will lay one over the other.

PorKen

I'm debating whether to go to an even -4°.
Having equal TQ and HP number looks good on paper.

Retard does seems to beef up the 5000 range, without taking as big of a TQ hit at 3000 as I thought it would, going by logged airflow numbers.

The RPM of the peaks has move up a few hundred RPM, but I'm happy the torque is still there.
It's the nature of the narrow 106 LSA S4 cams, I suppose.

The valley after the flappy (closed) peak is noticeable, unfortunately.
More retard makes this valley deeper and deeper.
It won't take any more ignition there, so it's not fixable.


Max advance at full load is 25° in the various TQ valleys - much lower at the peaks, though.
I've gone to 92 octane (usa/aki, 98 eu/ron). Even with retard, it was still knock happy on 89 (95).
Again, the 106 LSA, AFAIK.


If the EIS does increase airflow, it would require a separate tune/chip for it.


In the graph above, the green line is X-pipe, 24# LH, with stock EZ.

BC

Fuel limited tuning. You have the patience of job.

ptuomov

I think (but do not know) that you can move the flappy close torque peak up by filling the back of the plenum by block filler or down by adding a spacer.

Stromius

Heja Ken!

Två frågor....

Will the late 88's with the higher compression make any difference in the tuning you are doing?
Are the 19# injectors going to have to be replaced (again) to 24#? Not a big deal..just curious

FredR

Ken,

Your work continues to put a smile on my face. Contrary to my expectations of my "problems" being linked to my woeful ineptness at tuning- that or a naffed motor, you seem to describing quite a number of things I have noticed with my efforts so perhaps I am doing better than I give myself credit for [bearing in mind I have no access to a dyno here].

My top end pinging invariably initiates at about 5300 rpm and I pulled the timing back to about 27 degrees. with the auto box I feel it is more or less irrelevant what happens after about 6k rpm as the cams seem to be on their way out, albeit the motor seems happy enough to spin up there.

When next I do some sharktuning I will take a look at retarding the cams- that should be worth a couple of degrees of advance relatively speaking. I am also interested to know whether my breather project will improve potential for spark advance. First impressions are that oil consumption has dropped dramatically but still too early to tell.

I am also wondering if the EIS, having a lot of bare metal surface, is contributing to inlet air temp heat pick up. For sure it will not improve that aspect but whether there is any significant increase over stock remains to be seen.

I also noticed that things wobble quite a bit around the point where the flappy transitions [not too surprising]. What I have found strange from my efforts is that there seems to be an awful lot of cells at the low end where seemingly little is going on, and yet in mid range to top end [where we are more interested] the rpm ranges seem suspiciously broad and presumably that in part is what you have been trying to iron out. I dare say Porsche had their reasons for doing this whatever they were.

Not sure where I want to go from here. I have a set of stock S3 cams ready for modification- given your knowledge of these it would be interesting to hear your thoughts on how well these would work in our S4 motors.

It would also be interesting to learn what cylinders you saw "pinking" initiation on- mine were pinking predominantly on 2 and 6- any co-incidence or what to 2/6 big end failure? I was always of the impression that knocking can cause big ends to fail, albeit our ignition control system should prevent this. 95 RON and stock advance produced some big corrections on my motor [4 or 5 degrees pull back- but not every time I went there].

During our hot summers I try to keep away from 5.3k unless I am really hot *******.

Regards

Fred