Norton928

Hello Everyone,

I just had my 1987 928 S4 automatic run on a dyno, as I'm fairly new to the 928 world, I was wondering if the following figures sound right, or does my car need some work. Unfortunately I don't have a scanner, but here are the numbers.

Max HP 258.68
Max Torque 271.09

Dyno: DynoJet Mode 224x.

Car: 1987 Porsche 928 S4 automatic - stock except for autothority chip.


The dyno guy did the pulls in third gear, as that was their general recommendation for automatics. Next time, should I use 4th gear, as I believe it's a 1:1 ratio.


Maintenace on the car is up to date. No issues that I know of.


Please let me know your thoughts.



Thank you.


Norton

S4ordie

Sounds reasonable to me for a stock 87 S4. Might be able to find a few more just by making sure it is in its best state of tune. If you wish to increase it incrementally, things like X-pipe is an easy way to get another 10-15hp. Installing a RMB (rear muffler bypass) and removing all sound deadener from the interior adds another 120 audible horsepower.

pcar928fan

My '88 S4 has a RMB and AutoThority Chips (probably not much better than a stock chip) and it makes 263HP and 267Tq on a DynoJet...

Lizard928

Go to liftbars.com and get the cam tool. Then dial in the cams to 1 deg of retard.
Also make sure your MAF and O2 sensor are working correctly.

Iwanna928

Colin

Should I do the same when I put the euro cams on a US 4.5L?

Stephen

Norton928

O2 sensor is new. The MAF is the orignal unit I believe, but I have cleaned the hot-wire on the MAF with electrical contact cleaner.

Was third gear ok to use for the dyno run?

For the cam adjustment tool, is that something to be used when replacing the timing belt. Reason I'm asking is I had the belt replaced last fall, along with the water pump, and would hate to have to get into that again so soon.


Thanks again everyone.

Norton

danglerb

Dyno's are for tuning, measure a baseline, make a change and test for a difference, but they have no real calibration so HP varies from one dyno facility to the next or even with different operators. Your numbers are ballpark normal, but could actually be a bit high or low depending on how the dyno is set up and the test performed.

If you want a higher HP "number" try a few shops and mention you want a higher HP number and they should be able to accommodate you.

If you want to check for a change in performance, repeat the test without changes to the procedure.

Norton928

Just looking for a ballpark number to see if I'm in the expected performance range

GregBBRD

You are.

IcemanG17

For a stock 928 S4 automatic that is right where it should be..... 258whp is around 323 flywheel.....

Most automatic S4's dyno between 255-270whp depending on what is done to them....

edi1

had my 88s4 on a dyno last saturday 282.2 hp rear rear wheels

Tom. M

Lets see the curves. Sometimes the flappy isn't working and your power might be low, but in general your numbers seem OK. Where were the HP and torque peaks?

pcar928fan

That is very strong if it is an automatic! Just slightly behind my rear wheel numbers on both my GTS autos.

SeanR

Rogers Diamond Blue dyno'd today at 263hp, I forget the torque numbers though.

IcemanG17

This is reasonable.....especially for a 5 speed....

Sharky's best runs were 279whp and 286whp with intake spacers...but thats otherwise stock 88S4 with cats, RMB....