pantera928

If I had to pay someone to work on it, that would probably be true. If that were the case, I could not afford to own anything these days. Mine would have been a parts car when I bought it due to the amount of money would have taken paying someone to get it where it is now. That being said, I probably would have been better off financially turning several of my past projects into parts cars but where is the fun in that.
Being an ex British Leyland mechanic, these things seem relatively easy to work on and achieve success.
Now, about that "N20", what is that all about. I am lost on that one. Wait, my brain just kicked in. Nitous oxide! Got it.

Dennis K

I have a set of S3 cams that have been modified to fit in an S4 head. Some threads regarding this:

https://rennlist.com/forums/928-foru...n-s4-head.html
The only update to that post is that ends of the S3 cam are now cut off and pins are inserted into the oiling holes, just like the S4.

Some more pics of the modification in process:
https://rennlist.com/forums/7001480-post19.html

The process of extending the journal has been refined even further and now Jim has a really slick piece of engineering/fabrication to affix the thrust collar to the cam. See it in person and you'll puzzle over how the hell it was done.
https://rennlist.com/forums/928-foru...e-cam-mod.html

blown 87

You also might want to talk to another member here named Polecat, he has a Pantera also, it is a VERY nice car.

I agree with half the fun is taking one that for most is just done and making it something, mine started as a 400 dollar car.

IcemanG17

It should also be noted that this took Dennis's engine to 387whp!!!!!

However if you are looking for mods to increase performance by FAR the best is to make sure your 928 is running at 100% to start with!!! Hopefully someone nearby has a Hammer or Theo scanner to test the condition of the Knock Sensors, Hall Sender and Throttle Position Sensor....

I say this because I had an excellent running stock S4...when the Hall Sender and 1 knock sensor died it totally fell on its face...I don't have dyno runs but I would say 50whp!!!! I did have some great data from my dyno program..I'll look for it

IcemanG17

https://rennlist.com/forums/928-foru...ht=sharky+dyno

found it

terry gt

Colin , aka lizard has new cam sets coming soon . There is several grinds to choose from . the S3 cams are not the same as GT cams , that are NLA .

Dennis K

Some further explanation on the difference between S3 and GT cams . . .

The lift and duration of S3 and GT cams are the same. For both, intake duration is 219° at 1mm lift, intake lift is 10mm, exhaust duration is 205° at 1mm, exhaust lift is 9mm.

The difference is in the lobe separation angle. Due to the cast-in, center-drive chain sprockets, the lobe separation angle between the intake and exhaust cams is fixed, based on the grinding of the cam lobes.

GT's have a LSA of 110° and S3's have a LSA of 114°. (On my engine, I wanted to have the wider LSA.)

Hope this helps.

pantera928

387 RWHP! how did he accomplish that? I would love to see 320 RWHP. Stroker? Nitrous?
Not sure what a Hammer or Theo scanner is? Any in the Atlanta area? I assume that they can only get my car up to the original 316 HP? Not miracle machines are they? I feel like the car runs well (looks like crap) but there could always be something going undetected. This is my first S4 and almost all of my experience is with 16 valve cars.

Regarding Polecat, I think he sent me an inquiry a while back about Panteras. Two totally different animals but both fun in their own ways. I sold my first 928 and a vette to get my Pantera.

blown 87

I am sure he did more than just cams to get that much power at the rear wheels, or a adjustable dyno.

A Bosh Hammer is a Bosch scan tool, no they are just like any other scan tool, can only read codes and data.

pantera928

Greg
I am sure he did more too. Just curious as to what it was. So, will any scan tool work on a S4? I really thought they were too primitive to reveal much info.
I had a bit of trouble with a late model Mustang GT the other day on I-20 and it has given me the bug to increase performance. Would be pleased with 320 RWHP. I think that would take care of things. For now anyway!
Thanks

blown 87

No, it has to be a Porsche 928 one with the right cables.
I have tens of thousands of dollars worth of scan tools, and can not read the codes on a 928, it is my next scan tool buy.
honestly I have really never had a need for on on a 928, but most of the ones around here are S4's, 88 or older.
the old Hammer I had just seemed to always be broken, after the third time I gave it back to Snap-On.

320 at the rear wheels is about a 20% increase, that is 60 HP or so, a pretty big number.

I am a fan of blowers myself.

pantera928

I guess a couple of people have scared me from blowers on a 928. Maybe i should not be. I have done it to American and Japanese cars but never a German one. I don't really want to screw up a motor that expensive. THat being said, I have had nothing but success with the motors i have doen it to. Maybe I am paranoid but a couple of old time Porsche 928 mechanics have said that I would be creating a time bomb. They specifically were referencing to ones from one of our better known vendors. Of course many of them won't work on any 928 that is not stock.

EspritS4s

There are a lot of miles on some SC'd cars here. If you run lower boost, it can be a very straight forward bolt on upgrade with no need to even open up the engine (assuming good compression/leakdown). Modified S3 cams would be a bigger project.

blown 87

Send me a PM and tell me who around Atlanta said what if you would please.

Poor tuning is almost always the cause of loosing a motor under boost.

mark kibort

yep, and Ill add that i did the converson as welll from the S3 cam to make it fit the S4 heads. I got 320rwhp a few times using these cams, matching the original Holbet cams that were thought to be GT prototypes. lift is larger on the GT cams vs the S4 cams. I also ran equal length headers, but no other mods but a fuel regulator and KN filter.

the mods are really only to the one driver side cam. the rest just need the ends cut off the rear. the mod is to widen the bearing surface at the front of the cam.