Some important data for power users!

Kurt B · 03-03-2002, 11:16 AM

Subtitle: Wilmington, CA: Fulfilling all of your hotrod needs.
Weigh stations + empty, flat roads with no humans for putting it all together.

First off, my acceleration has been a mystery, even to me and a point of contention of people in distant lands who don't see the same performance out of their life-partners. I wondered if the GTechPro was simply broken or if my mods have really improved the car's acceleration.

1st off, my reputedly heavy Cabriolet tipped the scales at a whopping
2540 lbs. with 1/2 tank of gas. There is no rear spoiler, just a freshly repainted decklid. I weigh 175.

I did several runs for HP using the GTechPro factoring in my weight as well since I weight myself with clothes before I left!

At 6000 RPMS shift 1st and 2nd gear, the car produced a peak HP of 186 and 187 RW = 215 and 216 Flywheel HP respectively

Shifting at redline, it produced 194 = 224 flywheel HP.
Some say it around 207 off the showroom floor in 84, but my manual says 200. I don't know what to go by.

Fitting in a few very clutch friendly 0-60 times while I was at it produced 5.73 and 5.69 seconds. The car remains effortlessly below 6 seconds.

Everyone can (and of course will) draw their own conclusions on what is going on here, but I have simultaneously reduced the weight and improved the HP over stock without tearing down the engine or cross drilling the rotors. It is also possible that the weight station and the Gtech pro are both busted and that it's still a heavy 6.3 second cabriolet, of course.

Get a Bursche, dump your cat, slap in a chip, and remove all of your AC, and frankly, you'll be owning a different car in my humble opinion, which is becoming less opinion and more data driven every weekend!

Bobboloo · Bobboloo's Garage

Kurt ,
You forgot to mention one of the other things Wilmington has... the largest self service junkyard in the world. I was down there at Pick Your Part yesterday to get a mirror for my sisters Stanza and I saw an early 912 in the yard. There wasn't much in the way of good useable parts but I did find a good headlight switch $5, shift boot $1 and shift knob free.
It was the 1st time I've seen a 911 or 912 body car in there. I see 914's from time to time.
That place is great. A friend of mine needed 2 doors for her Mazda. I found the doors in the matching color ,complete with glass and interior panel, for $25 bucks a piece.
Sorry didn't mean to high jack your thread. By the way nice improvements for relatively small mods.

Bobby
I love LA....

P.S. I just remembered that that 912 had the brackets for mounting a VW motor in it. If anyone needs them let me know soon so I can get them for you before they crush it.

falcon · falcon's Garage

kurt,

Great numbers. However, by removing the cat...will your car pass the dreaded visual and CO/HC California smog test?

Jack Olsen · 03-03-2002, 02:19 PM

I've seen 200 pound weight variances in so-called 'certified' scales. And G-Tech Pros are reputed to be a little on the optimistic side. But still... it sounds like you've breathed some new life into that car.

Kurt B · 03-03-2002, 05:42 PM

I'll put the Cat back on in time for emissions. With clean bolts, which it has now, it's a 20-30 minute job tops.

Interesting information Jack. +/- 200 lbs for thos public scales. I guess I ought to weigh it in different locations several times. I removed the back seat padding as well as the back high tops (just left the cushion and carpet, looks fine), to rid myself of another 28 lbs.

Now, 2540 from 2755 would mean 215 lb drop from stock. This would be the removal the AC all of the stuff in the trunk, the cat for a pipe, and the stock muffler.

The hoses for the AC are quite heavy, there are also the condensers and the compressor. Everything including the blowers is quite heavy--but I don't know how much exactly.

I will say this however. When I calculated the max HP at the rear wheels assuming the car's weight was, including me 2930 lbs, the device produced 226 rear wheel HP--which is clearly excessive--which is why I decided to get it weighed.

Now, the only way this would be working to my complete disservice is if the scale read low by X amount and the Gtech is giving generous readings. Certainly possible.

Time to take it to a dyno!

pwd72s · 03-03-2002, 06:37 PM

Kurt? "0-60 in 5.46 seconds overall average".....guess you're FAST, man...

Jack Olsen · 03-03-2002, 06:38 PM

Just playing Devil's Advocate, here, I'll point out that different dyno units (even the same type/manufacturer) will vary, too.

dickster · 03-03-2002, 11:40 PM

in my (limited) experience your figures seem about right (hp) for what you've done.

i would get it dynoed though, and somewhere thats experienced with porsches. ask them what they usually get with bog std cars etc. that way you've got something to gauge the results to.

thats what i did anyhow!!!!

RarlyL8 · RarlyL8's Garage

Kurt -
I don't know how things are done in California, but we have several aluminum recycling plants here. Scales tend to be pretty accurate, they are calibrated for lighter vehicles. Give it a try.

widebody911 · widebody911's Garage

I've tried the local truck scales, and I don't think it's accurate. I have doubts about the G-tech, but it's a fun toy. I took the neighborhood RiceGrrrl for a spin yesterday. She wanted the see how the g-tech worked, so I set it up for a 0-60 run, and promptly ran a 4.91