SM flywheel conversion gone wrong
Thread Starter
Instructor
Joined: Nov 2000
Posts: 171
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From: Huntsville, AL
SM flywheel conversion gone wrong
Well, it may seem that the machine shop did not take off enough material off the flywheel. Put everything back together and could not engage any gears. Put the vette on jack stands to see if the clutch was disengaging. Put the vette in gear and had the wife depress the clutch as I tried to turn one of the rear wheels. This was a no-go, so this the only conclusion I can come to, am I on the right track before I begin the tear down again..
Thanks,
DJ
Thanks,
DJ
Thread Starter
Instructor
Joined: Nov 2000
Posts: 171
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From: Huntsville, AL
Bluewasp-That was my first thought, bled them several times..
bye byeL98-96 LT1 Camaro Flywheel 10125379, During my research I found not mention of changing the stud
tell me more...
I'm really leaning towards the flywheel dimensions, because I was getting throw-out bearing and front retaining bolts interfence. With the clutch full depress I was getting a metalic noise. Now that I have things apart, I can see marks on the throw-out bearing. What should the final measurement be on the flywheel? Thanks fellas for replying...
DJ
bye byeL98-96 LT1 Camaro Flywheel 10125379, During my research I found not mention of changing the stud
tell me more...I'm really leaning towards the flywheel dimensions, because I was getting throw-out bearing and front retaining bolts interfence. With the clutch full depress I was getting a metalic noise. Now that I have things apart, I can see marks on the throw-out bearing. What should the final measurement be on the flywheel? Thanks fellas for replying...
DJ
Safety Car
Joined: Sep 2003
Posts: 3,599
Likes: 24
From: Orange County NY
St. Jude Donor '10-'11-'12-'13
DJ -
I am not familiar with the dimensions of the LT1 Camaro flywheel, but have read the tech articles regarding .090" needing to be shaved from the original surface, so I am guessing that is supposed to result in the correct positioning of the "face" of the flywheel with respect to the other OEM clutch components.
The longer pivot ball stud is used when you convert to a single mass flywheel from the 4+3 cars. This flywheel is thinner than the DM, and the "face" sits closer to the engine. Because the recessed portion in the center is also shallow, you must use an unsprung clutch disc, as the springs of a sprung disc will contact the flywheel bolts. Because the entire assembly (clutch, pp, t/o bearing, flywheel) sits closer to the engine, a longer pivot ball stud is needed to maintain proper geometry.
I don't think you need the longer pivot ball stud in your case, especially if you are already reporting interference. Are you using a sprung or unsprung clutch disc? Can you see where the components were coming into contact with one another?
I am not familiar with the dimensions of the LT1 Camaro flywheel, but have read the tech articles regarding .090" needing to be shaved from the original surface, so I am guessing that is supposed to result in the correct positioning of the "face" of the flywheel with respect to the other OEM clutch components.
The longer pivot ball stud is used when you convert to a single mass flywheel from the 4+3 cars. This flywheel is thinner than the DM, and the "face" sits closer to the engine. Because the recessed portion in the center is also shallow, you must use an unsprung clutch disc, as the springs of a sprung disc will contact the flywheel bolts. Because the entire assembly (clutch, pp, t/o bearing, flywheel) sits closer to the engine, a longer pivot ball stud is needed to maintain proper geometry.
I don't think you need the longer pivot ball stud in your case, especially if you are already reporting interference. Are you using a sprung or unsprung clutch disc? Can you see where the components were coming into contact with one another?
Thread Starter
Instructor
Joined: Nov 2000
Posts: 171
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From: Huntsville, AL
I'm using a sprung hub with this combo, it seems that the interference is between the Throw-out bearing and the transmission bolts when the clutch is fully depressed. I've got the tranny out and I'm in the middle of taking the bell housing off. After I get all the hardware off, I'm going to install the DM flywheel and measure, from an establish reference point, how far the face of the FW extends. I'll do the same for the SM flywheel. That should give me an ideal how more needs to be machined off...I think 
DJ
DJ
Last edited by djbraxton; Mar 17, 2006 at 10:50 PM.
Thread Starter
Instructor
Joined: Nov 2000
Posts: 171
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From: Huntsville, AL
Alright, now I'm confussed...when I measured from my reference point both measured the same, but when I looked at the flywheel side of the disk, there was noticeable wear marks just on the inner circumference of the flywheel side of the disk. I'm going to have the FW checked in the morning to see if it is machined level...any suggestions?
Later,
DJ
Later,
DJ
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Burning Brakes
Joined: Jun 2000
Posts: 1,148
Likes: 47
I ran into a similar problem when I did my conversion. I highly recomend you change the clutch slave AND master cylinder at the same time. The pivot ball does not need changing nor does the fork need modifying however you may end up enducing air in your hydraulics since the fork has now moved closer to the motor.
Hope this helps and good luck!
Hope this helps and good luck!
Thread Starter
Instructor
Joined: Nov 2000
Posts: 171
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From: Huntsville, AL
Vette Threat-did that resolve your issue? I was thinking that the machining of the FW (.090) was to compensate for the difference in the depth of mounting surface of the flywheels to the crank. Am I on track here or not
Thanks
DJ
Thanks
DJ
Melting Slicks
Joined: Jun 2000
Posts: 3,215
Likes: 6
From: Tampa Florida
I've done the mod with the same flywheel with no problems.
Having contact other than the clutch surfaces is rather odd.
My webpage has the part numbers I used-are they the same as yours?
Does sound like a clutch master/slave issue to me....090 is not much change in distance-I would expect the factory to build in more of a buffer before parts hit each other, etc.
Good Luck!
Having contact other than the clutch surfaces is rather odd.
My webpage has the part numbers I used-are they the same as yours?
Does sound like a clutch master/slave issue to me....090 is not much change in distance-I would expect the factory to build in more of a buffer before parts hit each other, etc.
Good Luck!
Thread Starter
Instructor
Joined: Nov 2000
Posts: 171
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From: Huntsville, AL
NoGo-thanks for the part numbers, this is where I got my information. I talked to the machine shop and he informed me that the new flywheel I had brought, had balance holes that were to deep. The one got from a friend was .020 thicker than the new one. So, he just machined the .090 off the flywheel thinking there was some tolarance or buffer that could be played with. This turned out to be a bad decision. The flywheel is going back tomorrow to machine off the difference. Thanks for the reply...
DJ
DJ
Thread Starter
Instructor
Joined: Nov 2000
Posts: 171
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From: Huntsville, AL
Brent,
Thanks for offer, I should be up and running tonight. Took the flywheel back today, he measured it and sure enough more material has to be cut. I'll post my results...
Later,
DJ
Thanks for offer, I should be up and running tonight. Took the flywheel back today, he measured it and sure enough more material has to be cut. I'll post my results...
Later,
DJ
Thread Starter
Instructor
Joined: Nov 2000
Posts: 171
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From: Huntsville, AL
Alright, finally got the GS back on the road. The SM flywheel and the addition of some 2151 super comp headers complimented the GS well. It was blast to drive before, but now I'm very well pleased with the outcome. When I installed the current cam, I knew headers would make this thing come alive. Little did I know how much the SOTP guage would peg in the red...I'll see how much gain at the Gathering in May. I Dyno'ed there last year and made 363 RWHP with cam/pocket port heads. Let see what the headers will add. The same dyno will be there this also.
Later,
DJ
Later,
DJ
