Easy Power Modifications

[Landseer]

I drive an 84 Automatic daily with the system in the right of the picture.

Its very nice. I doubt it provides power increase. (Only juveniles want lots of noise and wheel chirp. My message to them is buy a mustang.)

The 84 Automatic with standard timing is every bit as enjoyable as the 86 32V Automatic. The 86 is a little smoother, but both very powerful vehicles.

Adjust timing and leave everything else alone.

The only reason the 84 has this new system is that the old system was destroyed and I needed to replace everything. At that time, in early 2008, I had no network of folks to trade parts with. So I bought new and had it assembled.

The system on the left belongs to a third 84 car and is shown for comparison.

[harborman]

Try driving a stick in Chicago traffic and see how sporty it i'd

928 automatics are fairly fast cars, but none feel sporty like a 5 spd does, and nothing cheap makes them feel quick off the line.

[tmpusfugit]

Originally Posted by 76FJ55

The 2nd gear start didn't come into play till S4 (or was it 86.5) production. your 84 will have a normal 1st gear start.

My '84 will start off in 2nd gear every time unless I pull it back into Drive 2, or I nearly floor it in Drive. According to my owners manual that is how it is intended to work, unless I am completely confused....and this would not be the first time for that problem

[Landseer]

There's something wrong with it. Another guy on rennlist is having that problem too and hasn't found his cause.

Check your manual again.

You might have the pressure cable set so loosely that its upshifting very fast.

The change occured in summer 87 according to the 1988 service information documents, so it was in full force for 1988.

My 84 auto car has an 89 transmission transplanted in it. It starts in second unless given moderate throttle, then it starts in first or downshifts quickly to first.

My 84 trans (when it was installed), 85 and 86 all start in first no matter what.

Although, with a loose bowden cable, they rapidly upshifted and were sluggish. Other things can apparently cause this shift problem. Not sure what. Steve Cattaneo advised a guy recently that the B2 piston degradation might be the culprit. Not sure. I have changed one for other reasons, though, and its doable on jackstands.

[bwmac]

Originally Posted by tmpusfugit

My '84 will start off in 2nd gear every time unless I pull it back into Drive 2, or I nearly floor it in Drive. According to my owners manual that is how it is intended to work, unless I am completely confused....and this would not be the first time for that problem

That is the way mine works and from all the forums I have been at, these cars start off in second unless you put them in second and slow to a stop, or kick it down.. Some even start off in second even when manually pulled into 2 unless you pump the gas.

there are lots of treads on this

[Landseer]

Your car is different. Its an 89.

[Landseer]

You are not the first to report the transmission behaving like this. People have been confused by the 2nd gear start and erroneously thought that the later-year change was the answer to the problem they were having with the earlier transmissions, 84,5,6 and some 87.


These three pages describe how the 4 speeds should work prior to the change in 88.

[tmpusfugit]

Originally Posted by Landseer

There's something wrong with it. Another guy on rennlist is having that problem too and hasn't found his cause.

Check your manual again.

You might have the pressure cable set so loosely that its upshifting very fast.

The change occured in summer 87 according to the 1988 service information documents, so it was in full force for 1988.

My 84 auto car has an 89 transmission transplanted in it. It starts in second unless given moderate throttle, then it starts in first or downshifts quickly to first.

My 84 trans (when it was installed), 85 and 86 all start in first no matter what.

Landseer, it is good to know (I think) that my '84 transmission should normally start in 1st without an arguement...it doesn't. I did go back and review the '84 owners manual, that being the one I would swear said it would start in 2nd, and of course it does not....you are correct as normal. Thanks for the correction! But now I have something else to fix......

[Landseer]

Here's the way later transmission shift, the reference being the porsche tech service information bulletin for the s4 cars which was phased in during the S4 production

[XLR8928]

Originally Posted by PorscheOwner

27-28 that seems like a lot but I am by no means an expert on the matter. I assume that I will need to run 92-93 octane?

And as for exhaust I think it already has a different muffler on it. I really don't want to change the exhaust because the note right now sounds really nice both in sound and volume.

The ignition timing quoted was a dynamic setting (3000rpm w/ vac advance).
Static setting would be around 8deg btdc. Sound more resonable?
-Kerry

[bwmac]

Originally Posted by Landseer

Here's the way later transmission shift, the reference being the porsche tech service information bulletin for the s4 cars which was phased in during the S4 production

Thank you very much for that clerification Landseer.

I stand corrected

BTW awesome info

[Landseer]

No problem, I'm sure the situation will be reversed many times.

I've had a little too much time on my hands this year and have been reading the CD set documents like a novel.

[dcrasta]

Dont mess with Landseer. He has been 'in this game' for a while.

Thanks for the 'chart' man that was pretty good info there. Looks like my car is working well, but not to derail this thread.. Is a symptom of 'hard' shifting a vacuum line leak?

[tmpusfugit]

Originally Posted by dcrasta

Dont mess with Landseer. He has been 'in this game' for a while.

Thanks for the 'chart' man that was pretty good info there. Looks like my car is working well, but not to derail this thread.. Is a symptom of 'hard' shifting a vacuum line leak?

It can be.....I had the problem last week.....and it shifted very hard. Solved the vac leak and it shifts smoothly....in my case the hose had come completly off the line going to the TT and transmission....and I have not solved my starting in second problem.....

[dcrasta]

Thanks. Figures I missed one . I did the vac lines last weekend. I have to get under the car again anyway. Wish I had a lift.

[Maleficio]

I found my coupling hose disconnected two weeks ago. Fixed it, put a fresh coupler at the tranny, fixed my hard shifting. Shifts very smoothly.

[dkkim81]

Could I replace Y-pipes and cat-back without doing the headers? A mechanic told me headers need adjusting repeatedly, so I wouldn't want to deal with that trouble. Does magnaflow make a y-pipe and cat-back for the 928S? Which brand is the best for the 84 928S?

[Danglerb]

Nobody makes anything fun for the 928 that is Calif smog legal. The only options I know of that are legal, as in a muffler shop with a license will install it, are factory and the direct fit replacement in the Calif section of the magnaflow catalog.

My muffler shop made a Y pipe to match the US 85/86 manifolds, and combined that with a generic, but Ca legal at the time magnaflow cat, and made a cat back single chamber (loud) magnaflow muffler.

Its really less of a technical question than what you can find a muffler shop willing to do, as they risk a very large fine for messing with smog stuff improperly.

[JhwShark]

Originally Posted by dkkim81

A mechanic told me headers need adjusting repeatedly, so I wouldn't want to deal with that trouble.

Interesting...adjusting the headers??? I would like to see an adjustment mechanism? Anyone got a picture or a comment? I have never seen one...

Jon

[bwmac]

Originally Posted by JhwShark

Interesting...adjusting the headers??? I would like to see an adjustment mechanism? Anyone got a picture or a comment? I have never seen one...

Jon

I believe what the mechanic ment is that header bolts are always coming loose and if you don't continualy check them so that they stay tight, the gasket will blow.
I use two gaskets to get a better squash.
If you use a good quality header with a nice 1/4 or thicker flange then it is not so much a problem.
this page says they have heavy flanges.
Edelbrock.com - Exhaust - Headers - TES (Tubular Exhaust Systems)