schmidtwerk

Totally stock, stock chip, exhaust, air cleaner.

Patrik S

Quote:
Originally Posted by schmidtwerk View Post
Bill,
Had Gamroth stick a bore scope up the drain plug. Indeed regular 993 rods so its a standard 993 crank but with a tapered snout. Oddly he is perplexed by it, he has 2 genuine Cup motors there, neither with the tapered snout crank. He agreed the part number for the crank ending in "70" is cup but neither one had it. There was certainly something the factory didn't like about the standard non balancer pulley in the 3.8 with a triple belt.



This is very interesting and intriguing…

I have a 993 CUP engine that has a GT3R crankshaft ( a non tapered nose) with a 993 RS single pulley (993.102.050.40).

As I will keep my AC I need to buy a new crankshaft crank pulley with 2 or 3 sheaves. Or a serpentine fan belt kit from Clewett Engineering. None of them has a pulley that is dampened (HARMONIC DAMPER) like the 964 and 993Cup, 993 RSR.

I have the dual mass flywheel but was thinking of installing a RS lightweight flywheel (LWF) in the future. Or?

What is my best alternative?

1. Clewett serpentine belt Kit (http://www.clewett.com/index.php?mai...roducts_id=135)
2. 993 RS w/AC (993.102.050.41)
3. Have my GT3R crankshaft machined to a tapered nose and install the 964 pulley, 964.102.151.00, (harmonic damper 3 sheave)

Bill Verburg

Still have the cat?

That's very similar to mine, mine has turbo mufflers and no cat though & SW chip w/ custom programming. Also measured at the rear wheel. If I apply a 15% correction it come to 326hp@6500, actual at the wheel is 283hp on a Dynapak

schmidtwerk

Bill,
Yes it has the stock cats and the correct X51/RS mufflers.

schmidtwerk

Has anyone dyno'd a motor then put it in the car are chassis dyno'd to get an accurate drive drag or can the chassis dyno detect the amount in the coast phase accurately?

schmidtwerk

Dyno ran it on 92 octane 10% ethanol pump gas. No idea what zero ethanol would change.

NineMeister

The 9m Bosch FLA203/Dynostar rolling road does exactly that, it measures the coast down losses, adds them to the rwhp then corrects the total to DIN (or SAE) standards using the in built weather station. I would think that most other chassis dynos would work in exactly the same way. There is not definitive number for the % coast down losses because there are too many variables that affect the result, i.e.: dyno roller diameter (and number)/surface finish/weight, tyre type/width/diameter/pressure, wheel diameter/weight, gearbox type/ratios, flywheel weight and vehicle weight being just a few. This is why it is important to compare rwhp results only from the same dyno type or preferably the same on under the same test conditions. I prefer to always use the DIN corrected flywheel hp numbers so will only show them on the 9m graphs.

What I have found is that % gains from motor upgrades will be the same on different dynos, even if the numbers are different. I had this with a 9m 993 +2 engine package for a customer in Australia recently who's chosen rolling road gave numbers 15% lower than expected. Solved the problem by testing a standard 993Vr on the same dyno and finding that it was also 15% down but still showed the 17% relative gain that we predicted. As ever, don't get hung up on the numbers, just focus on the delta that you measure.

Cupcar

No, but I had a '92 USA 964 Cup and the engine made 272 HP when tested on a brake dyno at Andial to certify it for Carrera Cup competition.

So, I put my '92 Cup on a Dynojet chassis dyno and it recorded 251 HP or about a 21 HP "loss" compared to the brake dyno numbers.

Interesting thing here is I just built a 3.8 with 1995 non-varioram intake, stock 1995 port sizes, '96 varioram valve sizes and Schrick mechanical rocker cams, custom Mahle pistons to go with GT3 130 mm Ti rod bottom end using an 8 pound GT3 RS 4.0 flywheel .

This engine recorded 290 HP on the same dyno and using same corrections and using the identical 993 G50/32 6-speed gearbox I had in the 964 for its dyno runs

So, adding in the loss of the gearbox I would guess 310 HP on a brake dyno for my 3.8 which seems pretty consistent here.

Bill Verburg

The GT3R uses 996102.021.91 crank which is a much stouter crank than either the 993 or 964 crank, It has a straight snout, the crank pulley is 996.102.115.83 that is used w/ a serpentine belt. It uses the same 14x1.5 bolt to hold it on as a 993. These cranks don't use harmonic balancers like the 964 do.

trophy

Another little known tidbit of information, the GT3 Crank is around 3lb heavier than the 993 crank

01coccobet

Has been a while that I didn't come along.
what a progression and....
what a great trd!

Cupcar

My observation as well.

993.NINJA

X51 Question, Does Anyone Know ??
Was there any 1994-1995. 993. 3.8. 4WD. Non Turbo. 6 Speed. Non Varioram, RS, RSR, CUP & GT or GT2 993 made with slim bodies for racing ?

I'm interested because I have an X51 993 1995 Carrera 4 Non Varioram Slim body.

993.NINJA

Carrera 4

993.NINJA

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