Marc Shaw

While healthy debate is certainly encouraged, name-calling is beneath us all.

Please keep on-topic and civil or enjoy an enforced vacation from RL.

Marc

springer3

Derek and I just had an on-topic, highly civil, but not quite legal fun time running our cars side-by-side in a not-too-scientific comparison. We met on I-20 and immediately hit the pits for full tanks of 93 (R+M)/2 octane Exxon. We have not met except over the Rennlist, but we quickly discovered we have a mutual friend in the US Rugby world. Our mutual friend has a 997, and he trounced me handily when we did a similar comparison.

Air temp: 48° F
Humidity: Unable to determine, but very low (clear sky)

His car: 94 Coupe
RS lightweight flywheel and clutch
Upgraded/lowered suspension
Recaro race seat and harness
Cat by-pass
Primary by-pass
MAF induction modification
Race cage
17" wheels
His weight: a fit 220 lb

My car: 92 Coupe
Primary bypass
16" wheels
Otherwise, bolt stock
My weight: a slightly less fit 190 lb

I had a weight advantage. I carried a heavier driver seat and the weight of the Cat. He carries 30 lb more body mass, plus the weight of a full roll cage. My guess: his car is 60 lb heavier.

On I-20 there was too much traffic to do much, but we finger-signed the gear selected and on signal floored it. On some short runs before we encountered traffic, there was little difference, not even a fraction of a car length.

We got off the Intestate to a 1-mile long straight near Derek's home. It had double lanes, no side streets and, amazingly, no traffic each time we made a run. We rolled side-by-side in 3 rd gear, and on signal over cell phone, each floored it. We held pedal to metal up to the red line. Result: half of the time I got up by a fraction of a car length, other half he got up. My GPS said my maximum speed that day was 121 MPH - jail time if caught on a public highway. We traded cars just for fun, and I got a car-length advantage driving his car - possibly my 30-lb lower body weight, but I think I got on the throttle a fraction sooner on that run. At no time during the day could either of us passed the other in full one-mile straight.

Perhaps there is some truth to the myth that the white cars are faster!

The remarkable thing about the day is how closely matched the cars are. I would have expected a greater difference even if the cars were identical in most ways. I will confirm the driveability of the MAF system is excellent - no flat spots and just as smooth as the factory calibration on my car - a rare feat for any after-market modification.

I find I have a little bit of unexpected sweat in the arm-pit area, possibly the thrill of driving, but more likely the fear of jail time if we got clocked at the end of one of our runs.

Kudos to Derek for being a great sport. I was fully expecting to get trounced, and then I would have placed my order for the MAF system. It appears the factory pretty much gets the maximum safe power. Spark advance or raising the RPM limits seem to be the only cheap way to improve on the factory, and those could be pretty expensive in the long run. I recently drove 91 turbo (Boing 717's), and that is no comparison.

Heirsh

Thanks Springer.

Great info for all of us following the thread.

1pcarnut

Darn. Was kind of hoping for some dramatic differences. Joel Reiser(PCA tech chair) has been saying kind of the same thing, that there is a little to be gained with a chip, not much with a cat-bypass or air filter change, and after that it gets expensive.

Lorenfb

"The 964 is a 15+ year old car, leave well enough alone and get a life."

Sorry for the post, totally inappropriate and not directed at anyone,
i.e. only meant to dissuade some from potentially wasting money
prior to a full product evaluation (A late night poor choice of words).

Lorenfb

"Derek and I just had an on-topic, highly civil, but not quite legal fun time running our cars side-by-side"

That's the bottom line! Kudos to you both.

springer3

Removing weight is cheaper than adding horsepower. There are some pretty good threads on what to remove and the weight benefit. Handling and fuel economy improve as well.

I forgot to mention Derek has the LWF and RS clutch. His motor spools down noticeably more quickly than mine, but that could also be the MAF and new software. That mod puts my estimate of weight difference a little closer, particularly since that is rotating mass which has to be accelerated down the road and spooled up.

donoman

I really hate seeing "after" dyno's without "before" dyno's. Some people are even more **** and will do pulls early in a day, do the modification, then do more pulls in the same day --- those are my kind of people!

garrett376

To a point... carbon fiber to replace things is really dang expensive!!!

Ritter v4.0

Thanks guys for the perhaps less than scientific, but otherwise real world comparison. Perfectly valid IMO- and more fun than a dyno pull.

And a buck twenty one on I-20? You ARE brave!

warmfuzzies

I would still say this, if it makes you happy, if you are content with what you have spent, if that floats your boat, I'm happy for you. Seriously.
However we all have differing views, and means of achieving how we want our cars to feel and drive, subjectively or objectively.
I'm not really biased one way or the other and we should all be thankfull for the debate, but as we are all so different it should be a welcoming point to discuss these minor issues.
We should maybe just take more time over wise words, read twice, send once.......there's no Undo once you hit the end button.

Kevin.

TR6

When I tested three different chips and two different airbox configurations on a dyno, I did them all within the same hour! You don't get much closer to a dead level comparison than that!
https://rennlist.com/forums/showthre...ferrerid=43271

deoxford

Hi,
Guys I been busy with work,
The other day was a blast, thanks Springer for meeting me and doing the "real world " test. I have to say I was surprised we could not pull away from each other in any of the test.
Sometimes one car would get in the front but, you could never pull away . But It was a fun test for sure.
I wonder if the cat bypass should not be on there , and well now I really wonder what the number will be when I go to the dyno with the stock stuff on the car.
Like I said the test was a big surprise , I will say that his car did have 43k miles less then mine but would that matter?

Anyway, I had a good time , and I will still say that I am enjoying the mod and I look forward to doing the dyno test with the stock stuff to show everyone.

As for the LWf , that was the response it had before the MAF , but it would sometime die with the old set up and now it does not die.

On a side note.
Today I was at MBUSA , and I stopped at Barber on the way home and the Porsche school was running on the track...THey looked like they were having some much fun.I can't wait for the next track event.

donoman

Yeah, you particularly rock. Your comparison was awesome, probably one of the first real methodical and systematic experiments I've seen completed online!!

Ritter v4.0

Derek- PCA 'bama has a DE at Barber in March. Registration opens end of this month. Ask me how I know!
Lets go.

I did the Barber/Porsche school in Aug- that kick started things for me. Hellava lot of fun.
I'm looking forward to going back and driving my car this time. Its a very technical track and I expect my laptimes to be slower- at least intitally. PSM, ceramic brakes and 355 hp is a tough act to follow.