Lorenfb

AGAIN:

Test Procedure:

1. Stock Porsche dyno run.
2. "Pushed Timing" (generic performance chip) dyno run on #1 WITHOUT any engine mods,
e.g. intake or exhaust and using standard fuel, i.e. no 100 octane race fuel.
3. Tweaked (custom tuning of #1) dyno run WITHOUT any engine mods,
e.g. intake or exhaust and using standard fuel, i.e. no 100 octane race fuel.
4. Comparative analysis of all three dyno runs.

So, where're are the data? Is this that difficult, but again hyperbole & personal attacks are always
easier, right?

Red rooster

Loren,
Just compare a 964 and a RS 964 . Nothing different other than DME calibration. The end.

Geoff

N51

Gentlemen,

As with most here, I've done my research. For the cost ~ $350 -500 of a chip, I can reduce some significant weight. The chips hold out modest claims that few can feel. Bob Scotto suggests that a rolling road remap and 20hp(far more than any chip can deliver) can be significant on the track, but not necessarily felt on the street. I've no doubt.

That all makes perfect sense to me. And the sense of it drives me toward more costly solutions that few may consider. So, I see many of the experts giving their best assessment, governed by their experience. That's how it should be, and it is to everyone to decide. And it can all be decided without the personal assaults, no?

Noah

SimonExtreme

Good point, well made! So Porsche says you can get 10 bhp more by adjusting the map. I wonder whether they used an appropriate test proceedure

The other thing that puzzles me is that people suggest you cannot feel the difference the extra power makes. N51 quotes somebody who states you cannot feel 20 bhp on the street. I am sorry, but this is total BS!

I don't think I have any special gift but I know I can tell the difference of less than 10 bhp. I am sure most others can as well. The "you cannot feel it" type of comment sounds like it would come from somebody whose chip hasn't performed!! And on that point I will agree with Loren. There is a lot of rubbish sold in the performance chip market. However, that doesn't mean it's all rubbish.

Red rooster

Simon,
The whole thing that amazes this discussion is that others and I were going through 964 DME recalibration in 1989 so that the best performance for road and race series could be found.
That nearly 20 years later, people are still claiming that nothing can be done I find absolutely incredulous.
Ah well , Spring is on its way .

Geoff

fstockcarrera

+1 I agree complete Geoff.

Geoffrey and I have data (some 35-40 pulls) of various chips, exhaust, airbox mods ect. none with a fully stock exhaust but all of our data is with stock headers ( they are really very good ). There is know doubt that the rs chip yields Rwhp ( 11 rwhp) alone. A few more can be had with fuel and timing changes. even more with cat by pass, primary and secondary by passes, and air box mod . Should you bother for the street,?? I can't say as my car is a track only car, But it is fun to try.

Lorenfb

"Just compare a 964 and a RS 964"

Porsche Spec Book - WKD 424 520

911 Carrera/911 Carrera RS

Bore - 100mm/102mm
HP - 272 (6100)/300 (6500)
Torque - 330 (5000)/355 (5400)

Valve Timing - 911 Carrera/911 Carrera RS (deg)
Intake Opens - +1/+5 TDC
Intake Closes - -60/-58 BDC
Exhaust Opens - +45/+50 TDC
Exhaust Closes - -5/-2 BDC

The difference is ALL in custom chip mapping, right?
So, all 964 owners just need to get a RS chip mapping and then they have a RS
like for the 993 vs 993 RS.

38D

Quoting the wrong numbers (those are for the 993 & 993RS) does not make you look very credible.

Lorenfb

"Quoting the wrong numbers (those are for the 993 & 993RS)"

Correct! So let's see the 964 numbers, please.

38D

Here's the #s from the correct spec book:

964 RoW vs 964 RS
Max HP : 250 vs 260
Max Torque (Nm): 310 vs 325
Fuel grade (RON/MON): 95/85 vs. 98/88

Everything else is the same including bore, stroke, compression, etc.

Lorenfb

Porsche Spec Book - WKD 423 920

911 Carrera/911 Carrera RS

HP - 250 (6100)/ 260 (6100)

So, it's only 10HP with an additional octane increase requirement (95>98).
That's about 3-4 degrees increase in timing. Hardly anything to "write home"
about!

BORING!!!!!!!!!!!!!

Geoffrey

On Bob's blueprinted 964 racing engine running 93 octane Mobil 1 fuel, with cat, primary, and secondary muffler bypasses it produced more torque and HP throughout the entire range. This test was conducted the same day with the same temperatures on a freshly broken in engine. The test compared a stock C2 chip and a stock Euro RS chip. I believe I could probably get a few more in some of the RPM ranges if I could remap the chip and correct some AFR issues, but this is about as good as it gets.

The Euro RS chip produced rear wheel 10ft/lb of torque at 5000rpm peak
The Euro RS chip produced rear wheel 13hp at 6250 peak

I have modified the cam timing on Bob's car which accounts for the the 6100 vs 6250 RPM peak HP level.

I have the engine back in my street C2 and should get to testing the various chips in the comming month. I will publish all of the results.

MarkD

Well, I wouldn't call it boring since that is the reason people look at going to an aftermarket chip. Kind of the reason for this discussion.

However, I think more of a consideration might be the difference in recommended octane rating. That is what ALLOWS the increase in timing, right? In my part of the USA (Ca.) that is the problem. Fuel is the limiting factor here... all of the advance in the chip is negated by fuel here.

Lorenfb

"Well, I wouldn't call it boring since that is the reason people look at going to an aftermarket chip. Kind of the reason for this discussion."

No, the real issue as discussed on this thread is custom tuning which basically yields nothing
for a stock engine. It's been well known since the initial development of the internal combustion
engine that more advanced timing always yields more torque, i.e. to a point and with tradeoffs,
pinging (detonation). This is what ALL performance chips basically do for stock engines, as was
the case for the RS.

All it takes if a few more degrees advance and the engine always feels more responsive, but this
always requires more octane to avoid detonation or the for the knock sensors (964) to retard the
timing for an overall loss of power.

Bottom line: The value of custom tuning on a stock 964 engine is of no value given the marginal
results of the RS over the standard 964, hardly a great revelation!

MarkD

Yeah, I kinda thought I said that...
I'm sure you said it better.
Good luck on your crusade.