Terry Burger

iTrader: (4)

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
I'll buy the statement: "Automatics are more efficient than you think" before I'll buy the statement: "The locked A4 tranny will out dyno a M6 in most cases," which is what your original statement was.
</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">If I said that it was for dramatic effect only (and it appears to have worked!). The point I was trying to get across is that they are close enough that tranny type is a non-factor.

Jake99SS

Sit and spin in a desk chair. Hold your arms out to your sides then pull them into your chest. You'll go faster with your arms pulled in.

RAGEman

iTrader: (4)

I still disagree, Terry. I believe it IS a factor. Although not as big a factor as a few people may have previously thought.

Terry Burger

iTrader: (4)

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
I want to address and compare the Aft weight differences.

M6 flywheel that very heavy,(stock) but, how heavy? 26 lbs?
Clutch disk 3-4 lbs?
pressure plate 12-14 lbs?
what would this total?

A4 high stall Tq converter is about 30 lbs?
flywheel about 6 lbs?
</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">The M6 clutch setup is ~54#, and the 9.5" converters when full are around 34#. The weight isn't the only difference because the converter has most of its mass towards the center, while the clutch setup has a linear distribution along its entire (and longer) radius.

nysbadmk8

terry.. no matter how smart you think you sound.. you are a true idiot

RAGEman

iTrader: (4)

Terry, help me out here, Work = force applied over a distance (force*distance), correct? The only proof needed for the statement: More work is required to move a fixed amount of mass around an axis the further from the axis the mass is, would be that as the radius (distance from the axis) increases, circumference (distance the mass has to travel on one revolution) also increases. Then, as that distance (circumference) increases, the work required to move the mass over that distance also increases.

<small>[ June 10, 2002, 06:42 PM: Message edited by: RAGEman ]</small>

Max@Cartek

The weight of a converter vs. the weight of a clutch assembly isn't where most of the power is swallowed up. It gets taken up mostly by the oil pump up in the front of the tranny that produces soemthing like 130 psi of oil pressure and the more massive internals of a stock A4. Factor that. The only hot air here is in the space between your ears. Please argue some more. I kinda enjoy this. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

JPR

After reading all these scienific formulas, I know for a fact now that they must have slipped me the Beta exam in Collage. I can buy the fact that a locked down light converter is "as" efficient, but I am really struggling with the better than part. WOT made a good point about the pressure stresses on the front pump/planitary unit/Drum and the extra stress of pressure applied to the clutch packs and I think it would definately be easier to spin an M6 IMHO.

my00c5

Terry are you referring to my 460 rwhp c5?? Yes its a 6 speed and you forgot to tell every one that my car ran 11.60 @ 124.3 with a 60 ft time of 1.88 on street tires and 4.10's. It was 80 degrees out with race weight of 3340 with half tank of gas.

Just for kicks I used the 50 shot of nos and it went 11.13 @ 128.5 ON STREET TIRES .

Car has nothing removed for weight savings. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

And yes its a cartek 346 heads/cam car NO STROKER <img src="http://temp.corvetteforum.net/members/tempsites/montessgirl//fender.jpg" alt=" - " />

<small>[ June 10, 2002, 07:47 PM: Message edited by: my00c5 ]</small>

Terry Burger

iTrader: (4)

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
I can buy the fact that a locked down light converter is "as" efficient, but I am really struggling with the better than part.
</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I'm willing to settle for "as" efficient. My point from the beginning was that I'm not buying the A4 excuse. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
WOT made a good point about the pressure stresses on the front pump/planitary unit/Drum and the extra stress of pressure applied to the clutch packs and I think it would definately be easier to spin an M6 IMHO.
</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">There are many factors in each transmission that effect their relative efficiency, but its not practical to discuss them all. Empircal results dictate that a locked & stalled A4's dyno on par with M6 numbers. That is all that matters to me. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

To answer WOT, an engine oil pump uses ~3-5hp to oil the entire engine. I'd argue the fluid pump in an A4 (which is the torque converter AFAIK) uses less than half that. In other words, moot point. In fact having an oiling system might be more efficient than having the entire box full of fluid (M6 style).

Terry Burger

iTrader: (4)

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
Terry are you referring to my 460 rwhp c5?? Yes its a 6 speed and you forgot to tell every one that my car ran 11.60 @ 124.3 with a 60 ft time of 1.88 on street tires and 4.10's. It was 80 degrees out with race weight of 3340 with half tank of gas.
</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I said 124mph and 3340# race weight. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

That is all that's important here. The fact that its a C5 and it comes lighter stock doesn't really matter to us. I could argue the whole more aerodynamic angle but again from my experience its mostly moot.

nysbadmk8

so terry can you explain this weird thing: why does every A4 dyno less then an M6?

RAGEman

iTrader: (4)

I wouldn't say the difference in efficiency between an automatic tranny and a manual would be "moot." In my observation, the T56 is around 3-4% more efficient than the 4L60E. This would make Peter's horsepower curve peak between 401.7 and 405 RWHP, if he had a 6-speed car. Which, for those not mathematically-inclined, would be a gain somewhere between 11.7 and 15 RWHP. That still may not be a number that is "up to par" with some of Cartek's other dyno's, but that is a different argument than saying the difference in efficiency between the A4 and the M6 is "moot."

<small>[ June 10, 2002, 08:10 PM: Message edited by: RAGEman ]</small>

nysbadmk8

im going to re-dyno once the headgasket is replaced... the blown headgasket could of been one of the factors... but i still think 390rwhp is alot

The Alchemist

iTrader: (19)

Not to stir the pot, but didn't JS and 2002SS have very similar packages installed around the same time and dyno very similarly?

I know JS had bigger long tubes, but even he said that they didn't gain him that much over the ported macs which is what Dan (2002SS) had.

I think that the difference isn't a percentage, but rather a fixed number, i.e. if the transmission requires 10-15hp to rotate, it will require that if the motor makes 300hp or 400hp.

Just food for thought. I like the way this post is going with informative posts rather than just flames.

XLR8NSS

iTrader: (4)

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by The Alchemist:
<strong>Not to stir the pot, but didn't JS and 2002SS have very similar packages installed around the same time and dyno very similarly?

I know JS had bigger long tubes, but even he said that they didn't gain him that much over the ported macs which is what Dan (2002SS) had.

I think that the difference isn't a percentage, but rather a fixed number, i.e. if the transmission requires 10-15hp to rotate, it will require that if the motor makes 300hp or 400hp.

Just food for thought. I like the way this post is going with informative posts rather than just flames.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I think your right about the fixed number but, with more power the parts will be accelerating faster which will require a little more power. I think the drivetrain loss between a 300 and 500hp car will be similiar but, the 500hp car should show a little more loss. IMO

I could be way off though. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

John

ls1fun

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Terry Burger:
<strong>[QUOTE]
To answer WOT, an engine oil pump uses ~3-5hp to oil the entire engine. I'd argue the fluid pump in an A4 (which is the torque converter AFAIK) uses less than half that.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">If the design is anything like the TH350/TH400 then there is a pump on the very front of the tranny. It's considered a seperate part from the TQ CNV as in if you had to replace it due to wear.

JS

iTrader: (4)

Brein,FWIW are packages were different.

I dynoed ? RWHP MORE using the Dyna's.
The Macs held there own til about 4500 rpm then the Dyna took over all the way to 6800.

JS

RAGEman

iTrader: (4)

Forgive my ignorance, but what is AFAIK?

XLR8NSS

iTrader: (4)

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by RAGEman:
<strong>Forgive my ignorance, but what is AFAIK?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">AFAIK it means As Far As I Know

<img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

John

<small>[ June 10, 2002, 10:26 PM: Message edited by: XLR8NSS ]</small>