1988 944s

[Dan Himan]

Ok so i am trying to fine tune the S, she has good torque but does not have the pick up she could. I found a bosch FPR on her, i found that the one on is the recommended one, but would she perform better with the OEM one?

[John_AZ]

Before you purchase a Porsche OEM FPR, you should test the fuel pump pressure at the fuel rail. If the Bosch is in spec, you would not need to purchase the OEM

Fuel injectors loose 6% of their performance over time and usually more in 23 years.

Service the fuel injectors at WitchHunter Performance - Injector Cleaning & Flow Testing Services or similiar and change the O rings and hats.

A quick upgrade is to switch to Iridium spark plugs. This would give you a little extra HP if used with premium gas.

Tune up tips: 944 speed tech article

Pickup should improve.

John_AZ

[AaronM]

Given that the EFI system is a Bosch Motronic system, the OEM FPR is going to be a Bosch part anyway. As long as the part that is in the car is rated at the correct pressure (i.e. you're not using a 3.0 bar regulator where a 2.5 bar is called for or vice versa) there should not be issues.

Can you clarify what you mean by, "has good torque but does not have the pick up she could"? Are you saying that the engine pulls well under heavy load but stumbles when throttle input changes quickly? Or is it something else?

If the issue is that it doesn't seem properly responsive to throttle input, you may want to check the throttle position sensor. It's not terribly uncommon for the TPS to wear out over time.

[Dan Himan]

It has moves when up to speed, up hill down hill.. thru the turns, it seems that it could get to speed faster. It handles throttle changes well. Is the TPS with the wiper arm thing. I actually moved the arm a little. Maybe i should do the check that posted on Clarks Garage.

[AaronM]

Originally Posted by Dan Himan

It has moves when up to speed, up hill down hill.. thru the turns, it seems that it could get to speed faster. It handles throttle changes well. Is the TPS with the wiper arm thing. I actually moved the arm a little. Maybe i should do the check that posted on Clarks Garage.

No, the TPS is mounted on the throttle itself. It's not the Air Flow Meter (AFM) that has the "flapper door" to measure airflow. The TPS is on the throttle pivot, opposite the side where the throttle cable attaches.

The early 944s cars were high-RPM cars that really were not as responsive at lower engine speeds. It's definitely an engine that you'll want to keep at 3,000 RPM or above if you want to get the most out of the car. You can cruise sedately at lower RPM, but it's always going to pull hardest in the upper revs. The later S2 cars had more low-end grunt

Also, none of the 944 cars (except the Turbo) are particularly fast in the straight line and even the Turbo is lacking a bit of hole-shot since the turbo doesn't begin to spool until around 2,500 RPM. The 944S has a 0-60 time of around 7.5 seconds (IIRC factory claimed 7.7 for the US models, some owners claim high 6's though and while I know Porsche's factory numbers are always conservative I doubt that they are _that_ conservative). To put that into perspective, my grocery-getter Volvo manages 0-60 in 6.4 seconds. The 944 just ain't built for acceleration. If you expect it to snap your head back then it will always seem that it could get to speed faster.

If the problem was with the AFM (the "wiper arm thing"), you'd notice some pretty definite drivability issues, not just some vague notion of "I think it could be faster".

[Dan Himan]

Ok i did some more reading on these. I'm a learning.

[mallard ducks]

Compared to the 8v's I've driven that have been in good engine shape, the "S" feels sluggish off the line even if it is ultimately faster. But none of these cars are fast from a standing start. Basically any modern family car is faster.

I think I can understand the feeling you're getting about good torque but pick-up not being what it could. Through being comatose at the wheel a few times I've found that my S will take off from standstill in 2nd gear, without bad lugging. So that's decent torque. But at the same time with this engine you don't perceive things to start happening until 3,500rpm because of the S's power "bump" starting at those revs.

[Dan Himan]

Yeah we notice that @ 3500, it kicks in. So it seems normal. Good to hear. I did check the TPS and AFM and both are good. Does installing a better coil do anything, i forgot what brand all ready?

[Brando]

You need a different chip to get performance gains. From the factory the system is "tuned" to come on around 3200-3500.

If you change exhaust, intake, etc get the appropriate chip.

Real power comes in the form of a turbo/supercharger setup. Just remember to upgrade brakes and tires.

[Dan Himan]

What kind of Chip? I know of the MAX , any others with success?

[Dave L]

In the S you have to drive it like this

[Dan Himan]

Nice, unfortunately there is always someone in my way.

[desertt5]

Originally Posted by Dave L

In the S you have to drive it like this

That's about the way I drive mine. We both seem happier that way

[rickharrison]

I have the 944S MAXHP chip...and it does make a difference. The torque curve is smoother, no noticeable flat spot any more. Dyno proven 6 RWHP IIRC...what`s that at the crank...10 hp or so.

I opened up my exhaust with 2.5 stainless from hi flow cat to hi flow muffler. No pre-muffler.

A 22 year old car at 0-60 in @ 7 seconds is still respectable in my books.

Take any nay sayers for a spirited drive on a track, and when they are reaching to hang on in a corner (or for a puke bag) , they will change their tune.

[porsche4life]

Do the witchhunter thing or replace the injectors.... New plugs, wires, cap, and rotor.... You'll feel it... I did in my 8v....

[Dan Himan]

Whats up with the PCB chip that claims to be adjustable?

[rickharrison]

never heard of pcb

[Endat]

Originally Posted by Dave L

In the S you have to drive it like this

I havent gotten to drive my 944S yet, but I drove my '90 Miata like this 90% of the time just to keep up with traffic, I imagine you would more than make up for the speed limit driving this S car like that near the redline...

[Dan Himan]

Its hauls butt.

[guru944]

Dan;

I had a few little gremlins when i got my S car last year, However it took a little time to get it to perform the way i like it for now. Replace the O2 sensor, they get lazy after 25k miles; NGK Iridium plugs and a great air intake pipe /cone filter works wonders. If you want also an MSD Blaster 2 or Nology coil will provide more juice & Torque all around. Then an cat back Exhaust upgrade 2.5" and good muffler (Dynomax Ultraflo) will release those spent up gases. Then finally a good chip upgrade will give you better all around response.
Brother, please feel free to visit my garage for pics on what I'm talking about.

PS: Your fuel pressure should be 3.0 bar ~44 psi on S & S2.

"As Fast as a Turbo S without all that lag"

Hope this post was helpful.
Later,