Keep braking motor mount bolts!
Thread Starter
Pro
Joined: Jun 2005
Posts: 660
Likes: 4
From: Fredericksburg VA
Keep braking motor mount bolts!
I took the car out yesterday for a cruise and I severed my main motor mount bolt when I got on it. The C6 Z06 was not happy when the bolt flew from under my car back towards it. Fortunately it went under it and also the other C6. No damage to ether car. Could have been much worse. I have poly mounts on this car and thought that would help to prevent that prob. I had the same issue with another car (70 Camaro) and just accepted that every oil change I would also replace the two mounts bolts. I tried both grade 5 and 8 bolts no real difference other that the 8 would snap off and the 5s would compress and eventually sheer. When I had the Vette motor built I feared this might happen so I put poly mounts in the Vette to give it some give the Camaro had solid mounts. Does anyone else have this issue and if so what did you do to correct it? I would prefer not to run a chain to strap the eng down nor do I want to weld in a mid mount setup. I know that several of you are running way more power than me (I have mid 500hp & 500Torque at the crank) how do you hold the engine in place?
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Originally Posted by waterplay
I tried both grade 5 and 8 bolts no real difference other that the 8 would snap off and the 5s would compress and eventually sheer.
What motor/trans and what HP? Your rear end is what?
Originally Posted by rihwoods
..also have those bolts checked as well... be sure they are at least grade 8...
Race Director
Joined: Sep 1999
Posts: 11,361
Likes: 383
From: Plano TX
That is odd. I'm also at the 500/550 level and tore the rubber motor mounts easily. But the poly mounts have stayed in one piece and I've never broken a bolt. Still running the 35 year old factory bolts. I second the theory on some form of misalignment.
Thread Starter
Pro
Joined: Jun 2005
Posts: 660
Likes: 4
From: Fredericksburg VA
I thought I was ok with the alignment (Mtr, Trans, Rear) I used VBP poly mount front to back. I just think it is odd to have this prob on two different cars. I guess I will climb back under the car with a straight edge. I will also look to see if ARP has some better mount bolts. I was hoping that someone had a similar issue? I guess I am “special”
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Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Buddy of mine's father had a '69 Camaro with a 600+ cube motor. So much torque it would pull through the breaks, or twist the frame if you stomped on it. He was using 20 yr old bolts. I think you havea unique issue.
Team Owner
Joined: Oct 2004
Posts: 23,831
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From: Springfield MO
St. Jude Donor '07
Originally Posted by Durango_boy
Buddy of mine's father had a '69 Camaro with a 600+ cube motor. So much torque it would pull through the breaks, or twist the frame if you stomped on it. He was using 20 yr old bolts. I think you havea unique issue.
Thread Starter
Pro
Joined: Jun 2005
Posts: 660
Likes: 4
From: Fredericksburg VA
I never rode the short bus before. I am not use to this feeling!
Everything appears to line up ok. I hope I just had a faulty bolt on this car and the Camaro had the alignment issue. New bolts go in ASAP!
"It's the bolt equivalent of your taillights... "
Not sure what that is all about, what did I miss?
Everything appears to line up ok. I hope I just had a faulty bolt on this car and the Camaro had the alignment issue. New bolts go in ASAP!
"It's the bolt equivalent of your taillights... "
Not sure what that is all about, what did I miss?
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Originally Posted by waterplay
"It's the bolt equivalent of your taillights... "
Not sure what that is all about, what did I miss?
Not sure what that is all about, what did I miss?
That's a joke between me and Batman. I have a tail light wiring issue. Very unique and hard to solve. He was saying your bolt problem seems isolated and unique...just liek mine did.
Let us know how the bolt install goes. Mark a date, and if and when they break again you can give us the timeline...
Drifting
Joined: Jan 2004
Posts: 1,991
Likes: 3
From: Piscataway NJ
I am running a 383 with poly mounts, not the hp and torque you have. But are you using long enough bolts with flat washers and lock washers? I use grage 8 with extra thick washers so it evens the load. Also torque to spec. it helps, not torqued, your are not getting full clamp load.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
You need to just fabricat your own bolts. Buy some titanium, enough to make say four bolts, and machine them yourself. Ten to one whatever problem you have, the titanium bolts would last a lot longer than your grade 8 bolts.
J/K.
J/K.
Thread Starter
Pro
Joined: Jun 2005
Posts: 660
Likes: 4
From: Fredericksburg VA
Originally Posted by Durango_boy
You need to just fabricat your own bolts. Buy some titanium, enough to make say four bolts, and machine them yourself. Ten to one whatever problem you have, the titanium bolts would last a lot longer than your grade 8 bolts.
J/K.
J/K.
I am still holding out for titanium rotors! I never used the lock washer or large washer I will try that and see what happens.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Originally Posted by waterplay
I am still holding out for titanium rotors!
Why stop there right? Man could you imagine if some rich douche had a Vette built out of all titanium metal parts? Five Million later...