Prothane motor mount is in!
I had the motor out of my car for 2 years...long story. I ended up with the Pro-fab K-member, and decided that a prothane engine mount replacement was in order also. the K was the easy part. I assembled the motor with everything but the headers and mounted the mounts to the block. the passenger side went in without a hitch once I got the mounts right side up 
the drivers side was a pita. the Pro-fab K isn't really welded together exactly perfect, so the mount hole was about a 1/4 inch off of lining up. I had to most difficultly pry the mount stand on the k-member over a little to get the bolt to go in. It did finally go in and the motor doesn't move at all. All in all I am really happy with the decision to change the mounts because of the difficulty in setting the motor/tranny combo in and lining it up. For the record this is the first time I've had trouble putting in mounts. I think this is due to the quality of the Pro-fab unit. for the money I recommend both upgrades IF you have the motor out already. Otherwise I would only do the mounts. I dread having to pull the motor out again to do anything to it. Hopefully I won't have to for a while. 6.0 + forged bottom end + all new parts = in the car for a really long time 
the drivers side was a pita. the Pro-fab K isn't really welded together exactly perfect, so the mount hole was about a 1/4 inch off of lining up. I had to most difficultly pry the mount stand on the k-member over a little to get the bolt to go in. It did finally go in and the motor doesn't move at all. All in all I am really happy with the decision to change the mounts because of the difficulty in setting the motor/tranny combo in and lining it up. For the record this is the first time I've had trouble putting in mounts. I think this is due to the quality of the Pro-fab unit. for the money I recommend both upgrades IF you have the motor out already. Otherwise I would only do the mounts. I dread having to pull the motor out again to do anything to it. Hopefully I won't have to for a while. 6.0 + forged bottom end + all new parts = in the car for a really long time Hey guys, glad someone brought this thread back up. My motor is out right now and my mounts are shot. Is it worth it to go with these or is the opinion to stay with the stock rubber ones? Either way mine need replaced. Also, is there a power limit that the stock mounts will hold? I've never heard anything mentioned of it but thought I'd ask. TIA!
I paid for someone to install my prothane motor mounts, went to the track this past weekend and now no rubbing with driver header against steering colum.When I saw the stock rubber mount I could not believe how weak it look and just worn, Glad I changed to polyurethane.
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Joined: Sep 2005
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From: Albuquerque
My shifter shakes and it drives me crazy. I put a poly trans mount....didn't really help. When I compared my '02 w/ my friend's '02....my motor has a lot more flex and play in it.
From what you guys are saying.....the mounts will be on order tomorrow. BTW...I'm paying someone else to do it. Here's a good question though.....if I have things disconnected and part of the work done....is it going to be that much more work to just put headers in (I'm going to go shorty....heard bad stories on the long tube)? What brand?
From what you guys are saying.....the mounts will be on order tomorrow. BTW...I'm paying someone else to do it. Here's a good question though.....if I have things disconnected and part of the work done....is it going to be that much more work to just put headers in (I'm going to go shorty....heard bad stories on the long tube)? What brand?
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Originally Posted by mrws6speed
My shifter shakes and it drives me crazy. I put a poly trans mount....didn't really help.
Originally Posted by mrws6speed
(I'm going to go shorty....heard bad stories on the long tube)? What brand?
Shorties aren't worth the $$ or the trouble. LT's are the only way to go if your getting headers. As long as you don't get SLP's ... you'll be alright for the most part: Hookers, Jet Hots, Pacesetters, Kooks, QTP's are all good quality headers.
Wow, I'm glad this 'lil thread I started helped a lot of people. I never thought it'd have as many posts as it has.
For the record, my poly mounts have held up just fine through the race season (probably 75 passes down the 1320 ). I've also added a poly trans mount and noticed just a little more vibration.
I'm very happy with the Prothane mounts, and I'm glad that I installed them, however much of a PITA they may have been.
Allen
For the record, my poly mounts have held up just fine through the race season (probably 75 passes down the 1320 ). I've also added a poly trans mount and noticed just a little more vibration.
I'm very happy with the Prothane mounts, and I'm glad that I installed them, however much of a PITA they may have been.
Allen
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Joined: Sep 2005
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From: Albuquerque
Originally Posted by FstBlkz28
Shorties aren't worth the $$ or the trouble. LT's are the only way to go if your getting headers. As long as you don't get SLP's ... you'll be alright for the most part: Hookers, Jet Hots, Pacesetters, Kooks, QTP's are all good quality headers.
My Friend told me the same thing. He said to get Kooks. I don't know...if I have to spend that much extra money and hassle....maybe I'll just do the headers at a later date. I'm trying to build a 2000 sq. ft. garage....I don't want to spend extra money now if it doesn't make sense. I just figured if it wasn't going to be that much more to put headers (shorties being easier), that it would be worth it.
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Joined: Sep 2005
Posts: 400
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From: Albuquerque
Originally Posted by DOUBT IT
Wow, I'm glad this 'lil thread I started helped a lot of people. I never thought it'd have as many posts as it has.
Allen
Allen
Allen,
You have no idea. This thread you started has been a great help! I ordered my '02 WS6 Convertible brand new. I only have 22K mile on it now. Since I got the car I've had all kinds of problems (good 'ol GM quality....or lack of it).
Before the first 1000 miles (during which the car wasn't driven hard)...the rear diff had to be replaced, the top didn't line up and tore the molding, the tabs for the top latches fell off and I had vibration problems. I don't think my car has ever been quite right.
The worst problem of all is that the shifter shakes (significantly...I've compared it to many other M6 LS1 cars). It is so bad and annoys me so much that it's almost to the point that I don't even enjoy driving the car many times.
I recently put a poly tranny mount thinking it might be broken or fractured. Not really any change there. Now after all this time I finally have what could very well be the root cause of what's driven me crazy about the car since I got it brand new. I already have the Prothane motor mounts ordered from Summit. I compared mine to my friend's '02 (exactly the same car...even the same color). The motor doesn't flop around like a broken mount, but I have more vibration with the motor. When they're reved, mine flexes more than his.
I have to say these boards are the best thing that has ever happened for f-body owners!!!!
I had the moving shifter problem, y pipe bang , headerbang you name it my engine was dancing under that hood. Replaced only the drivers side mount with a prothane mount and havent had trouble since. Checked out the old rubber mount. my car is a 99, and it was very soft, even had a small tear in it. I only did one side as the passenger side was going to be a PIA! On the books the time is 1 hr and 2 hrs or something like that. I started to do it in my driveway and it was not that easy due to the fact I couldnt get the car high enough to make working on it easier. I'm not a small person, so I said screw it and paid my mech to do it. A lot easier for him with the lift and I helped him as well to keep cost down.
