The saga continues! "New" engine blew up!

[Byron in Atlanta]

The car was running great after I installed the replacement flywheel that Aasco sent me. I had also installed the Accusump and drove the car 40 or 50 miles around town last weekend. Everything seemed perfect. Loaded the car up for the DE at Barber this weekend. Teched out ok and I drove 4 or 5 "parade" laps to get re-familiarized with the track. Everything seemed fine. Went out with my run group and did 2 pace laps....first green flag lap and I let a couple of cars go by as I wanted to bring it up to speed slowly. Got up to about 90mph on the first straight away, through the first turn and up the hill into the next straight, pressed the clutch for the hairpin, down shifted to 2nd and the dashboard lit up like a Christmas tree. The engine was dead, popped the clutch to restart, powered through the next straight.....kept it running through the next turns, but noticed a rattle on the subsequent straights. Backed out of it and pointed everyone by. Gave it a little more gas to get off the track and now it is a definite clatter. Limped it off the track...coasted into pits. Started it one more time with my helmet off....sounded like a sack full of wrenches! Pushed it onto the trailer and drove home! FUN!

Anyone know of any good basket weaving classes?

[silverboxter]

sorry! i had a similar experience. trying to save $10k to get "Helga" back on the road.

[AndyA6]

Oh no! What might it be???? Clutch related?

[DFW02S]

Sorry to hear that!

[Brucelee]

Have you spoken with Jake Raby? He might be of some help.

[Johnny Danger]

There seems to be every indication that installing a lightweight flywheel and clutch assembly on these vehicles is like tempting fate . Virtually everyone I know who has gone this route has regretted it . I've done all sorts of mods to my vehicle, however, based on what I've read and been told by others, I've chosen to stay clear of this application !

[jbs986]

Originally Posted by Johnny Danger

There seems to be every indication that installing a lightweight flywheel and clutch assembly on these vehicles is like tempting fate . Virtually everyone I know who has gone this route has regretted it . I've done all sorts of mods to my vehicle, however, based on what I've read and been told by others, I've chosen to stay clear of this application !

+1, I have read the same thing, are cars do not have harmonic dampeners. The O.M.E fly wheel has dual weight that works as a harmonic dampener, when people install lightweight fly wheels the lovely P.O.S crank shafts breaks.

Sorry and good luck dude.

[insite]

Originally Posted by Johnny Danger

There seems to be every indication that installing a lightweight flywheel and clutch assembly on these vehicles is like tempting fate . Virtually everyone I know who has gone this route has regretted it . I've done all sorts of mods to my vehicle, however, based on what I've read and been told by others, I've chosen to stay clear of this application !

i know PLENTY of people w/ the LWFW who have no issues at all. on GT3's, people have trouble with the front pulley coming loose & there is suspicion with that car of some weird harmonic issues.

with most boxsters & 911's, it's a non issue. just ask anyone who runs a spec boxster.

[insite]

Originally Posted by Byron in Atlanta

....pressed the clutch for the hairpin, down shifted to 2nd and the dashboard lit up like a Christmas tree.....

any chance of a type II over-rev here?

[Johnny Danger]

Originally Posted by insite

i know PLENTY of people w/ the LWFW who have no issues at all. on GT3's, people have trouble with the front pulley coming loose & there is suspicion with that car of some weird harmonic issues.

with most boxsters & 911's, it's a non issue. just ask anyone who runs a spec boxster.

With all due respect, I've spoken with many who have the LWFW assembly. And the ones who like it are clearly in the minority. Especially those who run their boxsters on the street .

[insite]

Originally Posted by Johnny Danger

With all due respect, I've spoken with many who have the LWFW assembly. And the ones who like it are clearly in the minority. Especially those who run their boxsters on the street .

no worries. i personally really enjoy mine, but i could see how someone might not like it. you are forced to shift very quickly in order to be smooth. it's also a little noisy & more difficult to launch smoothly.

as for actual problems resulting from the LWFW? i don't really think they're that common. pretty much the entire spec boxster community & the entire spec 996 community run the Aasco.

[Gilles]

Originally Posted by insite

any chance of a type II over-rev here?

+ 1...

Also the crank seems to be in one piece because the engine does run... unfortunately, with a clanking noise

I am sorry to hear this

.

[insite]

my guess is that a rod broke & the motor just hasn't siezed yet.



wonder if we can piece together one working motor from the two dead ones in your garage? ;-)

[Jake Raby]

I believe that I may know what has happened here and I am not willing to discuss it online. We have recently uncovered some revealing information that could be applicable to your situation.

I definitely want to see this engine.

The LWFW is more than likely not a problem, that takes time to occur with these engines generally. Like I said, I believe I know what happened.

[insite]

Originally Posted by The Radium King

sounds like it stalled when the clutch was depressed - ecu not able to react to the rapid rpm change associated with the lighter flywheel. so, what happens when you take a m96 from high rpm to off in a corner?

nothing, really. done it thousands of times. react how, out of curiosity?

[The Radium King]

i've read (ie, no ral expereince) that sometimes vehicles will stall with a lwfw, as the ecu anticipates a certain lag in rpm drop when the clutch is depressed. they way i read the initial description, it read like the stall happened when the clutch was depressed, not re-engaged ...

[insite]

Originally Posted by The Radium King

i've read (ie, no ral expereince) that sometimes vehicles will stall with a lwfw, as the ecu anticipates a certain lag in rpm drop when the clutch is depressed. they way i read the initial description, it read like the stall happened when the clutch was depressed, not re-engaged ...

ah; i hear what you're saying now. the revs do drop very fast. in the older cars, if the idle valve is the least bit sticky, it won't always react in time to keep the engine from stalling. i think the e-gas cars don't have this problem so much as the early ones. byron's was e-gas.

i was working under the assumption that the engine died after the downshift was completed. byron?

[Mike_Yi]

WOW! That REALLY sucks!

I'd love to hear the cause of the problem if you ever figure it out. I figured you had covered all the bases with what you've done to your engine. Now that my car is running again, I was thinking about putting an Accusump in it and tracking it again. After hearing this, I'm thinking maybe I'll sell it and buy a used Camaro or Vette.

[seningen]

Well I hope Jake is willing to spread the word.

I'm in the midst of building my Boxster S track car and would
hate to put all that time and effort into it to turn it into a
box of marbles my first time out.

thx,

Mike

[Burg Boxster]

Originally Posted by seningen

Well I hope Jake is willing to spread the word.

seningen,
I think you already have your answer...

Originally Posted by Jake Raby

...I may know what has happened here and I am not willing to discuss it online.

I'm sure this, as you called it, 'box of marbles' is a particularly sensitive subject since it has the "engine saving IMS retrofit/upgrade" . . .