Lizard928

Hey guys I have a couple of questions for you as i have recently purchased a Shark, it is a 1986.5 auto.

I have just had the timing belt done when I got the car, I have replaced the cam sprockets/gears as they were worn and causing the belt to ride forward causing premature wear on the belt. I also had the waterpump and front oil seal done at the same time and the tensioner rebuilt. it cost around $1700 cdn to have it done but now I have a piece of mind knowing my valves and pistons aren't going to hit, plus I have the guarentee of porsche trained mechs, normally I do all my own work but got lazy here. anyway enough rambling

the questions I have is #1 what is involved w/ converting the huge (S3?) intake ove to the S4 intake? as this is something that IMHO cleans up the bay and would make it alittle easier to change the plugs.

also does anyone have a webpage showing the 101 of ac systems on this car w/ a small troubleshooting guide as I am extremely mech inclined and will pick up quick just havent really looked at ac systems yet. Mine doesn't blow cold, I know I dont have a vaccuum leak as I have check the heater valve and it moves nice and quick the brakes are not soft either which can be caused by a check valve.

also I have read that the chip on the 86.5 is a soldered chip, is this correct and if yes do they swap the whole box w/ a removable chip to upgrade to?

I am not even going to ask abuot the couple of tiny electrical issues I am having as I havent taken out the voltmeter yet and I should be able to fix them easily even w/o having the manuals and diagrams yet. speaking of which anyone have a set of manuals they wish to sell?

thanx in advance for any responces.
Colin J A.KA. Lizard

Nicole

Hi Colin:

Congratulations to your purchase! And even though I'm not a guy, I'll try to answer part of your questions...

1. I have never heard of anybody bolting on the S4 intake on a previous model. It's an intersting idea, though,...

2. The AC is a very complex system. Wally Plumley has an extensive writeup about it, and if you are really nice to him, I'm sure he will send it to you at no charge. Try emailing him at tech@928gt.com.

You can find some information on the following sites:
http://members.rennlist.com/pirtle/svc.html
http://www.nichols.nu/tips.htm

3. I don't know about the chips in the '86.5, but I have heard from quite a few 928 S4 and GT owners that the standard chip upgrades pretty much don't do anything. Apparently, the only way to get a decent gain is to have them custom programmed. The highest gain I have ever heard of was around 30hp achieved by a combination of custom programming and higher flow cats. Some people here remove their cats to gain no more than 3% power, and the extra noise fools them into believing that the engine is more responsive than before. (I'm going to be flamed for writing that, but that's OK)

4. In regards to the electrical system, have you had a chance to lift the cover of the fuse box under the passenger side carpet? You will quickly learn that these beasts have a few miles of wires in them, and tracing electrical gremlins can be a major pain. The manuals surely help, as they do have the electrical layouts of each model year. I can't officially tell you to get at least a copy from a nice fellow 928 owner...

Watch ebay for used sets of manuals, or stay in touch with any of the "BIG THREE" to see when they are available again.

Best of luck, and enjoy your new beast!

urnotthesameina928

The chip version from germany makes the most signifigant improvement in HP next to the authority version.. With later year cars like the 87s onward the change is not that dramatic.. most dramatic for 85-86 cars.. Dave.

BarryW

I know of a shop that has installed S4 intakes on S3 motors. I asked Lucky at Devek Days about this and he said the bolt pattern is different so you have to drill and tap the head. I know the gaskets are different.

Lizard928

Thanks for the sites Nicole, they were all I did need, I should be able to get the system working properly soon.
I am going to be getting a copy of the service manuals soon (mainly for the wiring end of it) but I can figure out the wiring w/o it just as you pointed out takes abit longer,
and I do know the chip is harder to chang ein the 86.5 compaired to a 87 but what is the proccess, do you have to unsolder it and resolder the now one in, or do they send you and entire replacement box?
so the bolt pattern is different between the S3 and S4 heads eh, hmmmm, but drilling and tapping new holes does work? no chance of drilling into a water/oil channel? what about making an adapter plate instead, would it raise it too much and make it touch the hood? also what else is reuired, IE different throttle/cruise cables?

Lizard928

Oh the other question i forgot to ask does anyone know what pressure the fuel pump puts out (75PSI??) and how many gallons an hour it pumps, also shutoff pressure?
Thanx again Colin J

Don.

Info for converting S3 to S4 intake:

Picture at: http://www.marcus3.com/porsche_page/porsche_page.html

Article below ripped off from: http://members.rennlist.com/pirtle/keepers.html


From: marcus hutchinson [marcus3@mediaone.net]
Sent: Thursday, March 29, 2001 4:17 AM
To: 928
Subject: [928] Re: Marcus Hutchinson

>
> >
> > I would like information from someone who has BTDT.
> > Marcus Hutchinson, are you out there? Mark Anderson said you've done
this.
> > What are all the parts needed, how did you do it? Did it add much power?
> > Thanks,
> > Rick
> > 85 AT irisblau
>
>
Hmmm Been There, Done That, ok, ok I get it


The S4 manifold will bolt on easy enuf to the 85 32V, there is a few things
to do/change

1. Your fuel injectors will need S4 style rubber 'O' rings, they about $3.00
for each injector

2. You will need to change out the fuel rails to S4 style so they will bolt
onto the intake manifold
it's upto you if you want to get the fuel rail covers, they look nice and
help to keep injector noise low.

3. The S4 Idle valve is a 3 wire valve, the 85 is a 2 wire, use your 85 Idle
valve, you will also need
to use the 85 valve clamp, as the S4 one is bigger.

4. The vacuum hoses are a little different, If you can get hold of the 85
diagram and the S4 diagram,
the differences will become clear and the change over will be easier. I have
some if you need 'em.

5. The Flappy valve is controlled by the "brain" on an S4, the 85 does not
have this option, The flappy
opens and closes around 3500RPM, I built a unit to control it, basically a
frequency to Voltage converter
if you don't want to go that far, just get the flappy to stay open all the
time. Note: the flappy gets it's vacuum
from the brake booster vacuum system, not the 6way "Tee" under the Mass Air
Sensor. Also get the hose
from the intake manifold to the brake booser, the 85 one will not work.

6. You will need the S4 style rubber gasgets to seal the intake manifold to
the heads, the 85's uses paper,
and get S4 bolts, washers.

7. Throttle body cable is trickey, you need the plate and wheel that carries
the throttle cable up to the
bracket that connects all the cables from the gas pedal, cruise control and
transmission, this plate with the
pulley on it bolts on the back of the engine, behind the fuel pressure
regulator, get the cable too!
it will become obvious when you go to do this, the bolt holes only line up
to one pair of bolts, thank the gods this part
fitted on an 85 block otherwise the whole project would have become a
nightmare!
Get the bracket for all the cables that bolts on the side of the S4
manifold, remove the one at the front of
the engine, this part is not needed anymore, you can use your old cables,
just have to loop them over the brake
booster, the gas pedal was not any stiffer and the cruise control and
transmission cables were ok like this too.

8. When the old manifold is removed, you will see 2 studs rising from the
engine block, with rubber mounted
bolts on top, one each side, the 85 throttle body bolts onto these ...
(if they are still intact) remove the rubber and cut the studs off, the S4
throttle body will not clear these studs,
the S4 block does not have them, do not worry about how far you have to cut
them down, they wont leave
holes in the block, it's solid, BTW, cutting these off means there is no
going back

9. I never tested the difference between the 2 manifolds because I
supercharged the car and got even more BWAAAHHH!
the reason I swapped the manifolds in the first place was to get room to
install the intercooler unit...

10. I own an S4 so it was very simple, I just parked the cars next to each
other

see www.marcus3.com for a pic of how it looks

Lizard928

thanks Don that is what I was looking for on the swap, but the page didn't really show any info directly pertaining to this, But I have the basic info needed

Lizard928

also does anyone know what type of bulbe the PRND32 lights take as a couple of days after getting the car the D went out

Oh and I forgot to put this down pics of the car are avalible at
htttp://p-car928s.org