Anyone remember that old TV show "In Search Of" ?
This will be one of those longer running threads (cuz it is too cold to work on the car consistently). So it's more about picking your brains.
I took my car out twice this weekend trying to gain some insight into where the vibration may be coming from.
What we have is a 1969 corvette with a 400 SBC and a T5 transmission from an 1991 Camaro.
The nearly-new 10:1 performance SBC 400 came out of a lux-o-barge. It was mated to a TH350 and had no obvious vibration. It is externally balanced. Accordingly, the flywheel I threw on there is also externally balanced. I reused my clutch kit.
Back to my test drive.
If it makes any sense, the vibration feels like it is synchronized with the exhaust pulses. It feels like a rumble and maybe hearing the exhaust is reinforcing the feeling. It is also more noticeable on acceleration and not so much cruising at higher RPMs.
I am suspecting that this may relate to contact between the shifter base and the transmission console. I am very sure they are touching.
I also noticed that when I put my foot in it, the shift lever comes over quite a bit. I can't quantify it, but it feels like a lot; it yanks around in my hand. The motor mounts and the trans mount are new.
I am speculating that I mounted the trans too high when fabricating the removable crossmember.
I suspect that, in addition to the touching shifter base, when I accelerate, the trans itself might be coming over and touching the fiberglass transmission tunnel. I seem to recall there isn't much clearance under there.
My plan to test this theory is to replace the trans mount with a lower profile one giving me more clearance.
Here comes the weird question. I don't think lower profile trans mounts exist... can one trim one 1/2 an inch, and... would polyurethane be a better idea ? (All current mounts are rubber.)
What are your thoughts ?
D
This will be one of those longer running threads (cuz it is too cold to work on the car consistently). So it's more about picking your brains.
I took my car out twice this weekend trying to gain some insight into where the vibration may be coming from.
What we have is a 1969 corvette with a 400 SBC and a T5 transmission from an 1991 Camaro.
The nearly-new 10:1 performance SBC 400 came out of a lux-o-barge. It was mated to a TH350 and had no obvious vibration. It is externally balanced. Accordingly, the flywheel I threw on there is also externally balanced. I reused my clutch kit.
Back to my test drive.
If it makes any sense, the vibration feels like it is synchronized with the exhaust pulses. It feels like a rumble and maybe hearing the exhaust is reinforcing the feeling. It is also more noticeable on acceleration and not so much cruising at higher RPMs.
I am suspecting that this may relate to contact between the shifter base and the transmission console. I am very sure they are touching.
I also noticed that when I put my foot in it, the shift lever comes over quite a bit. I can't quantify it, but it feels like a lot; it yanks around in my hand. The motor mounts and the trans mount are new.
I am speculating that I mounted the trans too high when fabricating the removable crossmember.
I suspect that, in addition to the touching shifter base, when I accelerate, the trans itself might be coming over and touching the fiberglass transmission tunnel. I seem to recall there isn't much clearance under there.
My plan to test this theory is to replace the trans mount with a lower profile one giving me more clearance.
Here comes the weird question. I don't think lower profile trans mounts exist... can one trim one 1/2 an inch, and... would polyurethane be a better idea ? (All current mounts are rubber.)
What are your thoughts ?
D