porsche 928 RI

would it be the same 0-60 as the s4 auto since it is at the same power levels?

goodspeed928

The s3 is lighter

pcar928fan

I think gearing is different too...

dprantl

S4 has more HP and more torque, but is a little heavier. Gearing is the same for '87-'88 S4.

Dan
'91 928GT S/C 475hp/460lb.ft

Landseer

One of our resident wizards has figured out how to wind-up the power of the S3, which was apparently detuned from the factory when it was first introduced. Sounds like he can approach the S4 output. After all, its the same engine, actually has better cams. Can't wait to try it.

stolarzj

Actually the 85/86 is capable of more HP/TQ then a stock S4 once your get a few Porken products attached to the car.

pcar928fan

Dan,

It was S3 vs. S4, not '87 vs. '88. I know 87/88 have the same trans...

porsche 928 RI

since with the mods it has more power than the s4 and is lighter too shouldent the 0-60 be less than the s4's stock figures for an automatic?

dprantl

Ok, so a stock automatic S4 with a 2.2 rear pinion and 316hp and 317lb.ft torque weighing in at 3,550lbs officially does 0-60mph in 6.6 seconds. An S3 auto is 111lbs lighter. If you can get, say, 330hp out of one then you would probably be around 6.0 - 6.2.

Dan
'91 928GT S/C 475hp/460lb.ft

danglerb

Plus or minus 10% of HP doesn't translate into same percentage gain or loss in time to 60 mph, factors related to the launch make too much of a difference.

Peak HP is of less concern than what the torque curve looks like, specifics of gearing etc. My 91 Mustang only has something like 210 stock hp, but with a 5 spd and decent tires I can drop the clutch at 5000 rpm and the tires will hook and launch the car hard so very low 6.x sec 0-60 times are possible.

What happens in the first 10 to 20 feet make a huge difference in any kind of ET measurement, and the next 1300 feet have more to do with just the engine which shows up as trap MPH.

Nightfly

I've always thought it was more about gearing than squeezing the last Hp from the engine. Back in the '60's, the fastest traps in street cars were being done by guys with 4.11 or 4.88 gearing, sometimes in the 5's. Stock, 0-60 goats were beating pretty much everything 0-60 even though they eventually lost out in the quarter. What was the highest ratio rear end available for the 928? 2.8 something?? That kind of limits the straight line performance. Of course, you're going to limit your top end, but then again how often do you get to cruise at 170 anywhere in the states?

dr bob

Had a related discussion with a Subie STi owner who's done a few mods and tracks his car regularly. He does 1/8 and 1/4 mile drags, and would much rather do the shorter runs where his excellent gearing and 4WD traction make for great launches. HP and weight virtually identical to a 928 by the way, but a full second quicker 0-60. A 928 will suck his headlights out past 100, but most 'races' are over before that happens.

PorKen

A '86.5 with X-pipe, LH2²r/55 chipset, and S4 FPR will make a consistent +40 rwhp @ 6100 rpm (conservative), plus a lot more average torque.

But...'86.5 autos are piggies (compared to a '85 5-speed, EG.), with nearly the weight of a S4.