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Tremec 5 speed conversion in a 1970 Charger

KD have you tried different tires to reduce "road" noise? My house had a heavily used interstate entrance ramp behind it. What caused the most noise, tires. Thank god they moved the ramp. Now it's the drone of the highway.
Generally, the lower the treadwear rating, the fewer the tread grooves. A slick would produce far less noise than an all season radial.
My tires have a rating of 100.

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Those tires don't look like excess noise makers. Really liked this thread, you did a great job!
Generally, the lower the treadwear rating, the fewer the tread grooves. A slick would produce far less noise than an all season radial.
My tires have a rating of 100.

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It's also the spacing of the tread grooves. Mostly they are unequal and random in size - this reduces drone on the highway. Hard to see if yours have different sizes.
The numb steering may be due to lost motion.
Today I spent a few minutes looking for the problem. First up, I turned the key to unlock the column and turned the steering wheel back and forth. These Mopar steering boxes always seem to have some free play whether it is a 200,000 mile original or a fresh rebuild from Firm Feel. That has been my observations anyway.
The free play is quite noticeable in this case. I started it up and let the engine reach operating temperature, then tried again. The fluid pressure fills some of the void and free play is reduced but is still there. I yanked on the linkage near the idler arm and found some slop there. The Idler and Pitman arms are Fast Ratio units from Firm Feel. The slop isn't that bad but it is there. Jigsaw, my other '70 Charger, has no slop at all.
I had the Wife saw the wheel back and forth to allow me to look for lost motion. The idler didn't seem to have much slop in lateral movement but it did have some sliding up and down. Onto the drivers side....
Here is was....The steering box moves around some. That shouldn't happen. The steering box mounts on the K member were reinforced so I suspect that the bolts have backed out a bit.


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My steering box bolts came loose a few times, even at 80 lbs/ft or whatever they are meant to be torqued to. When you go from one direction to the other the box and k-frame must flex slightly which works them loose.
I knew the second time it happened - I could feel that dead area when changing from lane to lane.
I put some threadlocker on them that last time and they've stayed tight ever since, but they're almost a service item for me now, I check them periodically when I'm under the car.
All three steering box mounting bolts were loose by at least 1 turn. I backed them out one at a time, cleaned them with the wire wheel and slathered them with Locktite before screwing them back in.
The idler arm mount was an easy one too. The up and down slop exists due to the sleeve in the idler being about 1/8" shorter than the mounts in the K member. I added a washer in there to fill the gap and bolted it back up.
A test drive showed it to be all better.....response was as sharp as it should be.
For several years, I was considering a Borgeson steering chuck to replace this one. I thought of putting this Firm Feel Stage 3 unit in Jigsaw but the steering box in that car feels great and doesn't leak. I'm not in the habit of spending money needlessly....
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KD have you tried different tires to reduce "road" noise?

Ah, the dreaded road noise!
I just got back from a trip that encompassed almost 900 miles. I live East of Sacramento and drove to Southern CA and back, mostly freeway driving. I think that I have determined that the majority of the noise is the rain gutters and ill fitting vent window weatherstripping.
The 69 Charger 500, Daytona and Plymouth Superbird models all had deflectors on the outer sections of the A pillars. This most certainly smoothed out the airflow in this area. FBBO member CoronetDarter agreed that the wind noise comes from the same place in his 68 Dart. These cars have fairly upright windshields compared to newer cars and the stainless steel trim acts as a net for the wind. I may look into making or modifying something to cover this area for road trips of this distance.
This transmission though....
What a huge difference it makes. The FUN factor jumped several points for me. I had two passengers most of the trip and my goal was to make take-offs and shifts smooth enough to avoid sore necks. I'm getting better at that.
I've found that most drivers that line up behind me at stop lights don't even consider the possibility that this car might have a manual transmission and IF I'm on a hill, I might roll back a bit on take-off.
Cruising along at 70 or more is as easy as it is with a newer car.
On the way to Van Nuys, I knocked down a 13.2 mpg number driving through some hard rain. On the way back, I scored a 15.1 in clear weather driving 70 + mph, give or take. This is a 493 cubed, 850 4 barrel VS Demon carb, MP 528 solid cammed, A/C on, dinosaur tech engine with a 3.55 gear and a 28" tire in a 4000 lb car plus me, the wife and luggage. I could probably get close to 17 driving alone at 65 on flat ground.
Having the ability to drive fast on the freeway and keep up with everyone while seeing the tach under 2300 rpms is fantastic.
Ah, the dreaded road noise!...
That's why they invented loud mufflers and stereos! :lol:

I've found that most drivers that line up behind me at stop lights don't even consider the possibility that this car might have a manual transmission and IF I'm on a hill, I might roll back a bit on take-off.
This is an irritation I have as well. In reality, the car rolls back almost nothing, but it is still annoying to have someone very close to your back bumper. Now, when I come to a stop on a hill and someone else is right behind me, I let my car roll backwards just a little bit as the other driver is stopping. I have found it keeps them further away most of the time...
Thanks for the kind words. No car is perfect and this one isn’t either. I am finally able to relax and enjoy it since it has some road wear and scuffs.
After long trips, I ponder about what improvements I can make to make it even better. The sound deadener mats helped. I’ve never had a problem with heat coming through the firewall or floor but the noise was reduced by the “Fat Mat” squares.
I’ll start another thread elsewhere about noise and vibrations in these cars.

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I just spent a good part of my morning reading this whole thread and it is great!!! Very informative and was fun watching your trials and tribulations!
You went after each obstacle with determination and always found a solution. Hope it's still a ton of fun for you!!
I put a TKO 600 into my 70 Charger and removed the 727 about 18 months ago and I'm VERY happy. I highly recommend the pistol grip shifter. With some home fabrication to mount the shifter boot I was able to keep my center console. I have a lot of hot tips if you want to contact me. Like DON'T skip the step of checking the run out from crankshaft to bell housing centering hole. Silver sport is great. Instructions won't tell you this but they send 3 quarts of ATF and 3 qts syncromesh fluid. Run the atf for a few hundred miles to break it in then swap it with the syncromesh fluid. Good luck and enjoy.
The clutch master cylinder is a Wilwood unit with an adapter to fit the Mopar floor.
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It would be great to just place it against the firewall and drill. This not possible with the engine in place and those two right side holes are right up against the wheelwell anyway.
Oh, the lower left bolt?

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Trapped under the body of the master cylinder. You can't just set it against the firewall. You have to remove the adapter and separate the two, then get the bolt out.

I attached the clutch pushrod....

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I think it would had been easier to have the adapter threaded, and the bolts going from inside the car into the engine compartment.