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TKX Post Swap RPM Related Vibration

i take it as NO vibration issue prior to upgrade?

been a while since i used an SST Kit to perform a 727-to-TKO upgrade

on my conversion thread i took a straight edge from the block n valve covers and marked a few dots on firewall prior to upgrade just for reference. i think after the upgrade my engine rear was pointed downward from the marker dots. tough to remember but i my angle was good but i went ahead and added a shim to bring up engine close to the original marker dots, couldn’t get it exactly as before.

might be worth a try to shim it up at the trans mount if you have some reference pics to review


watermelon

IMG_2803.jpeg


IMG_2801.jpeg


IMG_2805.jpeg
 
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watermelon said:
i take it as NO vibration issue prior to upgrade?

been a while since i used an SST Kit to perform a 727-to-TKO upgrade

on my conversion thread i took a straight edge from the block n valve covers and marked a few dots on firewall prior to upgrade just for reference. i think after the upgrade my engine rear was pointed downward from the marker dots. though to remember but i my angle was good but i went ahead and added a shim to bring up engine close to the original marker dots, couldn’t get it exactly as before.

might be worth a try to shim it up at the trans mount if you have some reference pics to review


watermelon

View attachment 1969585

View attachment 1969586

View attachment 1969587
Click to expand...
That's smart. I'm going to do that when I swap in the 727/GV in my 72
 
watermelon said:
i take it as NO vibration issue prior to upgrade?

been a while since i used an SST Kit to perform a 727-to-TKO upgrade

on my conversion thread i took a straight edge from the block n valve covers and marked a few dots on firewall prior to upgrade just for reference. i think after the upgrade my engine rear was pointed downward from the marker dots. tough to remember but i my angle was good but i went ahead and added a shim to bring up engine close to the original marker dots, couldn’t get it exactly as before.

might be worth a try to shim it up at the trans mount if you have some reference pics to review


watermelon

View attachment 1969585

View attachment 1969586

View attachment 1969587
Click to expand...
Correct, no vibration prior to. Yes, mine does now tilt back more and according to SST, this is necessary for clearance, but there is some room into shim it up that I will do. Good call out to mark it; I didn't mark it, but I noticed right away due to a few reference points that I was very familiar with.
 
Did SST tell you how much more tilt? I've got to remeasure all my angles once i get my 4 post put together and see if I have room to shim the trans if necessary. I've been trying to make adjustments by shimming the rear and its gotten better, but not completely fixed. Really only happens in 4th gear at around 2300-2400 rpm.
 
nativefx said:
Did SST tell you how much more tilt? I've got to remeasure all my angles once i get my 4 post put together and see if I have room to shim the trans if necessary. I've been trying to make adjustments by shimming the rear and its gotten better, but not completely fixed. Really only happens in 4th gear at around 2300-2400 rpm.
Click to expand...
They did not say, but the solution is to shim up the trans or change the angle of the rear end. In my case, I did adjust the angle of the rear end to be in spec; if I shim the trans, it will be even more in spec, which I am planning to do.

Tremec has an app where you can use your phone to measure and do the calculations, but I just used an angle finder and manually calculated my angles for adjustment.
 
ill have to get my 66 back on it’s wheels soon and let it settle for a bit .. will get an angle measurement pic at some point

what’s weird for my tko is that with engine running i cannot shift into gear (1st, other) and without engine running i can shift into any gear i chose … not sure what’s happened but have not put on vary many miles for a few months now


watermelon
 
watermelon said:
ill have to get my 66 back on it’s wheels soon and let it settle for a bit .. will get an angle measurement pic at some point

what’s weird for my tko is that with engine running i cannot shift into gear (1st, other) and without engine running i can shift into any gear i chose … not sure what’s happened but have not put on vary many miles for a few months now


watermelon
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This issue that you are describing is because the clutch is not fully disengaging. You can shift with the engine off because the input shaft isn’t spinning. If you used to be able to shift, I would try re-bleeding the system and go from there.
 
I found that the header collectors were 3/4”, maybe an inch closer to the floor with the SST Tremec 5 speed in place. That is partly because my stock crossmember was modified and actually sat too low.
My car is as smooth as a new car though.
Now it is.
With the5 speed and 440/493, it always had some shake to it. An engine rebuild in 2022 included new balancing that must have corrected a balance flaw I had before because I now run a huge cam and the engine does not shake like it did with this same cam I used years ago.
 
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1970DCH said:
This issue that you are describing is because the clutch is not fully disengaging. You can shift with the engine off because the input shaft isn’t spinning. If you used to be able to shift, I would try re-bleeding the system and go from there.
Click to expand...

yeah ill redo it … in the car per sst instructions

had AI pull me some net stuff and looked at bench bleed of hydraulic cylinder

anyone doin that?

watermelon

IMG_9419.jpeg
 
I am incredibly excited to share that I finally figured out what was causing the vibration! As mentioned in my first post, I have been chasing a vibration that was not present with the automatic. It’s a 318 (internally balanced) and I confirmed no counter weights on the flex plate, I checked mounts, I check the trans mount, I checked my pinion angle even though the vibration was present at a stand still, I checked to make sure it wasn’t a misfire, etc. Literally everything led me to believe the issue was an unbalanced Flywheel/ Plate combo; even on Mcleod’s website, I found a tech install tip that recommended to get the flywheel and pressure plate balanced as a unit despite being zero balance->I figured this was the issue, so I planned to rip everything out and get the Flywheel and pressure plate balanced. I got my car propped up, disconnected the battery and proceeded to remove the exhaust. For some reason that I cannot explain other than divine intervention, I got the idea to take a look at the torque converter. Sure enough, there were counter weights on the engine facing side of the torque converter! In all my research, I never saw anything to suggest to check the torque converter; the consensus was if it’s a 318, it’s internally balanced and just to be sure, look at the flex plate for counter weights. Whatever the prior owner did, it translated to become an externally balanced engine. I went ahead and purchased the counter weight for the 360, put it on the flywheel and boom, vibration gone. I might be an idiot, I don’t know, but all I know is I’m so glad I thought to check the torque converter before I took everything out. Thank all of you for your help!
 
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IMG_8329.jpeg

Now I can finally finish putting the interior back together and remove the column shifter. I’ll eventually post my full experience for those looking to do a conversion.
 
Holy crap. Looks completely like trial and error. You can tell when they put weights across from each other :rolleyes:
 
RemCharger said:
Holy crap. Looks completely like trial and error. You can tell when they put weights across from each other :rolleyes:
Click to expand...
That’s what’s tough about obtaining a car without all of the history. The first issue I hunted for a while with this car and finally solved was oil starvation because the pickup tube was literally sideways in the oil pan. Wild.
 
I don't remember you stating the engine size before. In fact I'm having difficulty even now since it seems that you have a 318 but in the PM you state that it has a 360 rotating assembly.
That is an unusual combination. I'm guessing it was to increase the stroke using a 360 crank?
Nevertheless, this balance job:

1767864434210.png


Looks like the work of an idiot. NONE are factory and they sort of oppose each other. It looks like an attempt to compensate for an internal imbalance by trial and error without removing the transmission. You see, you can unbolt the converter, slide it rearward, rotate it enough to get a MIG nozzle in there and tack weld the weights without removing the transmission.
Some will say You got it working, no need to worry about why it wasn't right before but I am naturally curious and hate to deal with not knowing why. It is great that you got it figured out but I'd still be wondering why-why-why ???
 
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