Aasco flywheel is here. - 986 Forum - The Community for Porsche Boxster & Cayman Owners

ltusler · 02-27-2011, 10:34 AM

Guys,

Sorry I'm so late to the party. That is a picture of my crank. It was running a Aasco LWFW with a Sachs Sport spring clutch when it broke. During the rebuild Jake balanced both assemblies and I am currently running thr DMFW with a Spec non-sprung plate. Since I am interested in longevity over ultimate 10/10ths performace, I took the safer, but by no means absolute proven route. That said the HP and TQ put out by the Flat 6 3.8 with improved X51 upgrades, makes the advantages of the LWFW a moot point in my opnion. Now if Jake could come up with something to keep my skirt from flying up at 154 at the end of the main straight at Brainerd, I could get into the 40's and be happy!

Lon

Jake Raby · 02-27-2011, 10:55 AM

Quote:

Originally Posted by ltusler

Guys,

Sorry I'm so late to the party. That is a picture of my crank. It was running a Aasco LWFW with a Sachs Sport spring clutch when it broke. During the rebuild Jake balanced both assemblies and I am currently running thr DMFW with a Spec non-sprung plate. Since I am interested in longevity over ultimate 10/10ths performace, I took the safer, but by no means absolute proven route. That said the HP and TQ put out by the Flat 6 3.8 with improved X51 upgrades, makes the advantages of the LWFW a moot point in my opnion. Now if Jake could come up with something to keep my skirt from flying up at 154 at the end of the main straight at Brainerd, I could get into the 40's and be happy!

Lon

Lon,
My Wife goes that fast, actually he highest land speed record is only 153, so you have her slightly beat.. Are you wearing a Nomex skirt? Seemed to work for her. You could always couple your skirt with cloudsurfer's stiletto heels and have a true winning combination.

Anyway, the broken crank issue is being handled.. We finally decided to step up crankshaft production and have units mass produced from true forgings. The testing is going to be long and hard and we can't get it done fase enough. Most cranks we are seeing now are not passing magnaflux tests, even from bone stock street engines with DMFWs. Rebuilding without magnafluxing is like Russian Roulette with these engines. I received another X51 broken crank call last week, it was broken in 4 places, not just two.

ltusler · 02-27-2011, 11:21 AM

Jake,

Yes but she does it from a standing start, I comming out of turn 10. Anyway, we'll install a new crank once you get the individual throttle body and new cams worked out! But I'm sure thats another thread.

I am looking forward to all of the tracktime I can get this year. I'll get you a fresh oil sample early May.

cheetah · 05-23-2011, 11:07 AM

I know that this topic is from a few months back, but I was reminded of it while reading some of the other forums.

Are we sure that the rattling sound is coming from the engine? I have read that a lot of other vehicles with similar dual-to-lightweight flywheel conversions have similar rattling and their consensus seems to be that the sound is coming from the gears of the transmission and not the engine itself.

I tend to agree with is hypothesis as it seems to make sense: At idle, clutch out = sound. At idle, clutch in = no sound. So obviously something that changes with the clutch being pressed gets rid of the sound. That means we can narrow the problem down to something that changes when it is pressed.

What changes?

With the clutch in, the transmission and engine not connected. When the clutch is not in, the engine and transmission are connected. I believe that the dual mass flywheel dampens the engine vibrations from going to the transmission. With the light flywheel not dampening these vibrations, they travel to the transmission gears while the clutch is not in and the car is not moving.

The sound does sound like it is echoing from the transmission area and not from the engine itself.

One way to find out for sure: Have someone run an engine with the Aluminum flywheel on it without a transmission connected.

Anyone have any thoughts on this?

cheetah · 05-26-2011, 08:06 AM

Has anyone else with the lighter flywheels noticed that the sounds seems to be coming from the transmission, and not the engine?

insite · 05-26-2011, 08:29 AM

i never considered that since i figured my sprung clutch disk would settle it down. i'm putting it up in the air Monday to drop the tranny; i'll take a listen with it lifted & see what i think.

i always thought my release bearing was shot or something.....

cheetah · 05-26-2011, 10:31 AM

I now have a 2006 Variocam Plus 3.4L from a Cayman in my 986 with the AASCO / Stage 2 Spec Sprung Clutch. I also replaced the entire arm and throwout bearing when I did the swap, so everything is good shape. Mine makes the same rattle now as it did with my 3.2L.

When I put on the RSS underdriven crank pulley Dampener, it didn't change the sound in any way at all either.

Jake Raby · 06-11-2011, 07:56 AM

Insite,
we see that with EVERY LWFW that we balance, yours was no different.

Sorry about not having time to talk to you about it.. we were a little tied up with a car that was stolen for over a week and just showed up.. I had to Commandeer a Mini Cooper driven by a Priest to chase the Boxster down!

Long story :-)

AndyA6 · 06-11-2011, 06:32 PM

Quote:

Originally Posted by Jake Raby

Insite,
we see that with EVERY LWFW that we balance, yours was no different.

Sorry about not having time to talk to you about it.. we were a little tied up with a car that was stolen for over a week and just showed up.. I had to Commandeer a Mini Cooper driven by a Priest to chase the Boxster down!

Long story :-)

Please DO TELL!

Sounds worthwhile