[C2] Another TKO Driveline Angle Fail Thread
01-13-2017, 09:06 PM
#21
Pro
Thread Starter
.My mounts have a position they refer to as "factory". It puts the end rear of the engine in the same place as the original. I know it did because both the M21 and now the TKO landed with their mounting holes *exactly* over the factory mount position. Moving the engine forward (which is possible) would require a custom mount of course.
01-14-2017, 01:00 AM
#22
Drifting
For me, the whole operation only required a few hours on a Saturday afternoon. I was fortunate that none of the body mount bolts were frozen. On convertibles like mine the two body mount bolts in the convertible top storage area are often rusted solid from water leaks, but mine loosened up okay with some advance application of WD-40 to the cage nuts from inside the car. Some of the other body mount nuts are accessible from above for a squirt of WD-40.
I was surprised at how much four shims allowed me to raise the transmission tail shaft. If you think about the geometry, though, the pivot point is the engine mounts up front. A ¼” lift at the point where the transmission hits the tunnel translates to a much larger lift at the tail shaft (possibly even double).
I would encourage you to try this as something that is easier than some of your other options. The only thing I can think of that is easier than this is putting a shim on the differential snubber to push the nose down. It sounds like you have experimented with that but not had good results.
01-14-2017, 05:08 AM
#23
Pro
Thread Starter
I wonder if I could also safely remove a piece of that hump in the tunnel that is the first thing to interfere and seal it from the top. It seems the transmission would go up a little more again with just a small section removed. I didnt really want to mod the floor, but that would be a fairly small operation.
01-14-2017, 07:51 AM
#24
Team Owner
Errr...my experience is 'real-world' but a stock C1 chassis/engine...TKO-600 Keisler 'Perfect Fit' kit.
I had a vibration problem at speed and I was lucky I guess; driveshaft imbalance. Keisler actually reimbursed me the $85 for balancing and tuning it.
I assume you've already gone through all the info on 'phasing'....here's one article I read when sorting my issues out:
http://www.roddingroundtable.com/tec...driveline.html
I had a vibration problem at speed and I was lucky I guess; driveshaft imbalance. Keisler actually reimbursed me the $85 for balancing and tuning it.
I assume you've already gone through all the info on 'phasing'....here's one article I read when sorting my issues out:
http://www.roddingroundtable.com/tec...driveline.html
Last edited by Frankie the Fink; 01-14-2017 at 07:53 AM.
01-14-2017, 08:32 AM
#25
Drifting
I don’t think you should be uneasy about adding shims to the body mounts, as long as you add the same number of shims to every body mount. The body will still be in the same position relative to the frame, just higher. There should be no effect on things like door alignment. For someone like you who has put an LS engine in a C2, this task would be a piece of cake.
For me, the whole operation only required a few hours on a Saturday afternoon. I was fortunate that none of the body mount bolts were frozen. On convertibles like mine the two body mount bolts in the convertible top storage area are often rusted solid from water leaks, but mine loosened up okay with some advance application of WD-40 to the cage nuts from inside the car. Some of the other body mount nuts are accessible from above for a squirt of WD-40.
I was surprised at how much four shims allowed me to raise the transmission tail shaft. If you think about the geometry, though, the pivot point is the engine mounts up front. A ¼” lift at the point where the transmission hits the tunnel translates to a much larger lift at the tail shaft (possibly even double).
I would encourage you to try this as something that is easier than some of your other options. The only thing I can think of that is easier than this is putting a shim on the differential snubber to push the nose down. It sounds like you have experimented with that but not had good results.
For me, the whole operation only required a few hours on a Saturday afternoon. I was fortunate that none of the body mount bolts were frozen. On convertibles like mine the two body mount bolts in the convertible top storage area are often rusted solid from water leaks, but mine loosened up okay with some advance application of WD-40 to the cage nuts from inside the car. Some of the other body mount nuts are accessible from above for a squirt of WD-40.
I was surprised at how much four shims allowed me to raise the transmission tail shaft. If you think about the geometry, though, the pivot point is the engine mounts up front. A ¼” lift at the point where the transmission hits the tunnel translates to a much larger lift at the tail shaft (possibly even double).
I would encourage you to try this as something that is easier than some of your other options. The only thing I can think of that is easier than this is putting a shim on the differential snubber to push the nose down. It sounds like you have experimented with that but not had good results.
I don't know if any of this will help...sharing my experience fighting vibrations with my last TKO600 install. I had 2 vibration issues to solve:
Trans case touching tunnel: If that trans case is touching, it will cause a vibration...may or may not be what you are experiencing...my case was rubbing in that same spot...I didn't grind down the cover cause I wasn't that smart...I just raised the floors a little higher and it gave the necessary clearance. Next time I will trim the cover too.
Clutch/flywheel balance: In addition, I had another bad vibration at 3200rpms...did not matter the gear, speed, clutch position...turned out I had to get my flywheel and Luk 11" clutch (NAPA) balanced together...this was on a 383 with 400 crank stroker...externally balanced motor, etc...luckily I had the flex plate and a local engine builder was able to balance the flywheel and clutch assembly.
This solved my second vibration issue. Car was perfect after that.
In all, I pulled the eng/trans 3 times...once to realign the shifting blocks because I didn't check before I installed that the trans would shift freely I was not happy when I discovered) and two more times to fight/figure out the vibrations and at that point, I had the remove/install procedure down to an hour by myself...
I hope you get it sorted.
Cheers,
Frank
01-14-2017, 12:03 PM
#26
Drifting
I think for the most part, YES, the LS conversions have issues from time to time...the TKO swaps with the regular SB or BBs have less issues...that said, read my post #25...I had a few issues but they well within the "fixable" limits.
Last edited by Crunch527; 01-14-2017 at 07:04 PM.
01-14-2017, 12:24 PM
#27
Team Owner
I replaced body mounts just as gearheadjoe says...I did it an a few hours...I used a floor jack at the location of each body mount to slightly lift the body and replaced the bushing and shims. You don't have to loosen the bumpers. My car was totally rust free...all the bolts came out easily. I don't know how much clearance I got out of it...I did it because I wanted to replace the old body mounts.
I don't know if any of this will help...sharing my experience fighting vibrations with my last TKO600 install. I had 2 vibration issues to solve:
Trans case touching tunnel: If that trans case is touching, it will cause a vibration...may or may not be what you are experiencing...my case was rubbing in that same spot...I didn't grind down the cover cause I wasn't that smart...I just raised the floors a little higher and it gave the necessary clearance. Next time I will trim the cover too.
Clutch/flywheel balance: In addition, I had another bad vibration at 3200rpms...did not matter the gear, speed, clutch position...turned out I had to get my flywheel and Luk 11" clutch (NAPA) balanced together...this was on a 383 with 400 crank stroker...externally balanced motor, etc...luckily I had the flex plate and a local engine builder was able to balance the flywheel and clutch assembly.
This solved my second vibration issue. Car was perfect after that.
In all, I pulled the eng/trans 3 times...once to realign the shifting blocks because I didn't check before I installed that the trans would shift freely I was not happy when I discovered) and two more times to fight/figure out the vibrations and at that point, I had the remove/install procedure down to an hour by myself...
I hope you get it sorted.
Cheers,
Frank
I don't know if any of this will help...sharing my experience fighting vibrations with my last TKO600 install. I had 2 vibration issues to solve:
Trans case touching tunnel: If that trans case is touching, it will cause a vibration...may or may not be what you are experiencing...my case was rubbing in that same spot...I didn't grind down the cover cause I wasn't that smart...I just raised the floors a little higher and it gave the necessary clearance. Next time I will trim the cover too.
Clutch/flywheel balance: In addition, I had another bad vibration at 3200rpms...did not matter the gear, speed, clutch position...turned out I had to get my flywheel and Luk 11" clutch (NAPA) balanced together...this was on a 383 with 400 crank stroker...externally balanced motor, etc...luckily I had the flex plate and a local engine builder was able to balance the flywheel and clutch assembly.
This solved my second vibration issue. Car was perfect after that.
In all, I pulled the eng/trans 3 times...once to realign the shifting blocks because I didn't check before I installed that the trans would shift freely I was not happy when I discovered) and two more times to fight/figure out the vibrations and at that point, I had the remove/install procedure down to an hour by myself...
I hope you get it sorted.
Cheers,
Frank
Last edited by 66jack; 01-14-2017 at 12:26 PM.
01-14-2017, 03:35 PM
#28
Drifting
Ok great, thanks, you have given me some confidence. I have never touched the body mounts, but my car has had a pretty dry life and I have not met much resistance taking anything apart so far. Did you use standard body shims ? How many in total ? You are right, a little lift at that point translates to a larger gain at the tail, so I might start down that road.
I wonder if I could also safely remove a piece of that hump in the tunnel that is the first thing to interfere and seal it from the top. It seems the transmission would go up a little more again with just a small section removed. I didnt really want to mod the floor, but that would be a fairly small operation.
I wonder if I could also safely remove a piece of that hump in the tunnel that is the first thing to interfere and seal it from the top. It seems the transmission would go up a little more again with just a small section removed. I didnt really want to mod the floor, but that would be a fairly small operation.
I agree that removing that little bump in the tunnel would buy you some room. Check topside first to figure out why it is there. It may be related to mounting the console cover or tying into the dash.
Regarding your question about how many shims I added, I think it was four shims at each body mount. I just bought the reproduction shims from Paragon.
Note that the floor spacer blocks provided by SST will not be thick enough after the shims are added. For maximum benefit, these should be increased in thickness to make them a tight fit between the crossmember and the fiberglass floor. I had to add a couple layers of flat sheet rubber to my spacers to make them a tight fit after the body mount shims were added. I think the spacers can provide an extra 1/8" because the fiberglass floor is so flexible in that area.
Another poster said there is no need to loosen the bumper mounts, but I think that was just for replacing body mounts without adding more shims. It seems to me that for adding shims, the bumpers needed to be loosened to let the body rise with the added shims. The steering column mount at the firewall was another such location.
Regarding the risk of rusty body mount bolts, I think I found that all of the body mount bolt threads could be accessed one way or another for an application of WD-40. Some are accessible from below, while others are accessible from above by removing an access plate.
I think you will find this to be an easy way to get more transmission clearance.
01-14-2017, 04:50 PM
#29
Drifting
NOPE, no mis-speak...the engine shop asked if I had the flex plate that came with the engine from the builder...when I asked them why they needed it, they said they would use the flex plate as a guide to then balance the flywheel and clutch assembly...not sure what or how they did it...the fly wheel came back with several holes drilled in the back of it and when I put it all back together the vibration was gone.
I always thought an externally balanced flex plate for a SB 400 crank was a standard piece...meaning, whether or not I had the one that came with my engine should not have mattered...
It worked, so I didn't question them on it...
I always thought an externally balanced flex plate for a SB 400 crank was a standard piece...meaning, whether or not I had the one that came with my engine should not have mattered...
It worked, so I didn't question them on it...
Last edited by Crunch527; 01-14-2017 at 04:52 PM.
01-15-2017, 03:37 PM
#30
Pro
Thread Starter
Another poster said there is no need to loosen the bumper mounts, but I think that was just for replacing body mounts without adding more shims. It seems to me that for adding shims, the bumpers needed to be loosened to let the body rise with the added shims. The steering column mount at the firewall was another such location.
I spent some time yesterday looking at the mounts, seems they are all accessible and the threads look pretty good. The rubbers are all crusty and certainly look like they have collapsed/flattened a lot.
Rather than just shimming them, maybe I can renew them and return the original number of shims and get the original body height.
01-15-2017, 05:19 PM
#31
Drifting
Thanks for the heads up, I will do some research and see what else needs to be loosened for lifting the body or is it just the steering, bumpers and radiator support ?
I spent some time yesterday looking at the mounts, seems they are all accessible and the threads look pretty good. The rubbers are all crusty and certainly look like they have collapsed/flattened a lot.
Rather than just shimming them, maybe I can renew them and return the original number of shims and get the original body height.
I spent some time yesterday looking at the mounts, seems they are all accessible and the threads look pretty good. The rubbers are all crusty and certainly look like they have collapsed/flattened a lot.
Rather than just shimming them, maybe I can renew them and return the original number of shims and get the original body height.
My guess is that you won't get the desired transmission clearance by just replacing the donuts, but you could try that first to see what it buys you.
When I added 4 shims to each mount on my car, the main objective was to get some more hood clearance for a taller intake. The added space for the transmission height adjustment was just a bonus that I took advantage of. I did not have a vibration problem with my TKO 600 installation, but I was still bothered by the fact that the driveshaft angles were not within spec.
So, you might find that fewer than four shims gets you the transmission tunnel clearance you need for raising the tailshaft.
01-16-2017, 08:02 AM
#32
Drifting
daz_au,
I was thinking about the SST floor spacers that were mentioned in a previous thread? Any idea how their thickness compares to that of a hockey puck? Reason i ask is because hockey pucks seem to do the trick and have been a popular "spacer" to help raise the floors. I used a couple pieces of composite decking material sandwiched together...I think that gave me about an 1/8 inch more clearance than a hockey puck did plus it distributed the weight over a larger area.
Anyway, just a radom thought as I sip my first cup of coffee this morning...
I was thinking about the SST floor spacers that were mentioned in a previous thread? Any idea how their thickness compares to that of a hockey puck? Reason i ask is because hockey pucks seem to do the trick and have been a popular "spacer" to help raise the floors. I used a couple pieces of composite decking material sandwiched together...I think that gave me about an 1/8 inch more clearance than a hockey puck did plus it distributed the weight over a larger area.
Anyway, just a radom thought as I sip my first cup of coffee this morning...
Last edited by Crunch527; 01-16-2017 at 08:29 AM.
01-16-2017, 07:02 PM
#33
Pro
Thread Starter
So we dont have a lot of hockey pucks here in Australia, but they are 1" thick right ? The SST spacers are probably close to an inch high, but not quite and they compress a little as they get loaded. They went in quite easily for me, I am not sure how much height I really got from them !
02-10-2017, 11:48 PM
#34
Racer
Had been following this thread with interest due to contemplating the 5 speed swap myself. Wondering if you resolved your vibration issue?
02-11-2017, 08:53 PM
#35
Race Director
I've chased a high speed vibration for almost 10 years. I have a 66 vert with a Keisler 5 speed Tremec that I installed. It hasn't caused any problems just annoying. I have done the following with no success
Replaced body mounts
Rebalanced the flywheel
The Driveshaft Shop drive shaft balanced to 10k
Half shaft u-joints
Realigned the motor mounts
New snubber bushing on the Diff - Adjusted the angle up and down with no affect
Cut the top of the tranny
Sent the tranny back to Kiesler
Measuring the angles it's impossible to get the tailshaft of the tranny high enough. It points downward as does the pinion. There is no possible way to get the drive line angles opposite and less than 3*
I saw an article in HOT ROD this month and have started a dialog with The Driveshaft Shop as they now offer a CV Joint on the drive shaft. The guy I was talking with actually has a 66 Corvette that he had the same problem after the CV jointed drive shaft it fixed the problem... It's pricey but I'm going to chance it.
http://www.driveshaftshop.com/domest...-or-muscle-car
Replaced body mounts
Rebalanced the flywheel
The Driveshaft Shop drive shaft balanced to 10k
Half shaft u-joints
Realigned the motor mounts
New snubber bushing on the Diff - Adjusted the angle up and down with no affect
Cut the top of the tranny
Sent the tranny back to Kiesler
Measuring the angles it's impossible to get the tailshaft of the tranny high enough. It points downward as does the pinion. There is no possible way to get the drive line angles opposite and less than 3*
I saw an article in HOT ROD this month and have started a dialog with The Driveshaft Shop as they now offer a CV Joint on the drive shaft. The guy I was talking with actually has a 66 Corvette that he had the same problem after the CV jointed drive shaft it fixed the problem... It's pricey but I'm going to chance it.
http://www.driveshaftshop.com/domest...-or-muscle-car
02-11-2017, 11:41 PM
#36
Pro
Thread Starter
I dont know when I will get the time to do the mounts, hopefully soon !
02-12-2017, 01:35 AM
#37
Well..... my dream run so far modifying this car has finally come to an end. I have to admit I have had it good for a while with really no major dramas doing the LS3, suspension and brakes on my 64.
Last month I finally bit the bullet and had a TKO600 shipped over from SST. First of all, SST customer service is great. Apart from two bolts being the wrong size which I just replaced myself, the whole kit was very well put together and complete.
So I get it all installed, again no major dramas, used McRobb offset dowels to get a the bell-housing dialed in and everything bolts up nice. The transmission itself is great, shifts nice, drops RPM significantly in 5th of course and not noisy at all (yet anyway).
The problem is quite nasty vibration at around 65MPH that I have been trying to solve for the past month by getting the driveline angle even close to what it needs to be. The TKO is longer and even though its sitting on the supplied mount and very close to the floor (with supplied pucks installed), it points down at a steeper angle than the M21.
I have tried shimming the transmission up until it basically hits the floor and also tried all combinations of changing the snubber bushing (both thinner and fatter) to get a combination that gives me that close to perfect equal/opposite Z configuration.
I know I am not the only one, this forum is littered with similar situations... I just cant really see how this works for anyone unless they basically "relieve" the tunnel to allow the transmission to come up more.
I have seen at least one person try to shim down the rear of the pumpkin by putting a spacer between it and the carrier/crossmember. I am almost considering trying this as it would allow me to lift the front (pinion) without worsening the transmission to shaft angle which is already bad.
Its a real shame, the whole project is near perfection. Driving around town, this conversion is a dream... and anything up to 65MPH there is no detectable vibration. I have contacted SST and they sent me pretty much the same driveline angle info you can find on google, I guess they know it doesn't work out sometimes
Last month I finally bit the bullet and had a TKO600 shipped over from SST. First of all, SST customer service is great. Apart from two bolts being the wrong size which I just replaced myself, the whole kit was very well put together and complete.
So I get it all installed, again no major dramas, used McRobb offset dowels to get a the bell-housing dialed in and everything bolts up nice. The transmission itself is great, shifts nice, drops RPM significantly in 5th of course and not noisy at all (yet anyway).
The problem is quite nasty vibration at around 65MPH that I have been trying to solve for the past month by getting the driveline angle even close to what it needs to be. The TKO is longer and even though its sitting on the supplied mount and very close to the floor (with supplied pucks installed), it points down at a steeper angle than the M21.
I have tried shimming the transmission up until it basically hits the floor and also tried all combinations of changing the snubber bushing (both thinner and fatter) to get a combination that gives me that close to perfect equal/opposite Z configuration.
I know I am not the only one, this forum is littered with similar situations... I just cant really see how this works for anyone unless they basically "relieve" the tunnel to allow the transmission to come up more.
I have seen at least one person try to shim down the rear of the pumpkin by putting a spacer between it and the carrier/crossmember. I am almost considering trying this as it would allow me to lift the front (pinion) without worsening the transmission to shaft angle which is already bad.
Its a real shame, the whole project is near perfection. Driving around town, this conversion is a dream... and anything up to 65MPH there is no detectable vibration. I have contacted SST and they sent me pretty much the same driveline angle info you can find on google, I guess they know it doesn't work out sometimes
02-12-2017, 01:07 PM
#39
Race Director
Member Since: Nov 2000
Location: Beverly Hills (Pine Ridge) Florida
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I saw an article in HOT ROD this month and have started a dialog with The Driveshaft Shop as they now offer a CV Joint on the drive shaft. The guy I was talking with actually has a 66 Corvette that he had the same problem after the CV jointed drive shaft it fixed the problem... It's pricey but I'm going to chance it.
http://www.driveshaftshop.com/domest...-or-muscle-car
However, the comments regarding the 3 degrees or less for the drive shaft angles have to be laughed at for those of us with C1 Vettes. The stock drive shaft angles are already above 9 degrees, and with a longer trans (and shorter drive shaft), those angles will only increase!
I don't know if it has been mentioned before, but on C1 Vettes, there are angle shim plates (installed between the rear end at the spring mounts and the leaf springs) that can alter the pinion angle, to better match the trans angle. I doubt if something like that would work for C2..............but some amount of change with the snubber can only help.
Plasticman
Last edited by Plasticman; 02-12-2017 at 01:08 PM.