What would you do?
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Joined: Jun 2018
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What would you do?
My ‘68 442 came with a TH400 and 3.23s. Rear tires are 275/50/15s. Rebuilt 455 running E85 going in this spring which is expected to Dyno a little over 500 hp, which converts to about 350 hp here at elevation. Hoping for a tire roaster but plan on hitting some car shows up to 2 hours away as well. I do have a freshly rebuilt 4.10 posi axle as well. Willing to use the 3.23s or 4.10s and change tire and transmission. Would love to hear thoughts on how to proceed. I know the built 2004r and 700r4s don’t live forever behind the 455 torque but perhaps my hp loss at elevation make that more feasible. I’m familiar with gear vendor units but in a perfect world I would keep it more original. I know everything is a trade off so I want to err on side of tire roaster.
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From: Phoenix, AZ
The internet says those tires are 25.8" tall, which is about the same height as the 245-60-14s that I had on my car for over 20 years. I traveled to a lot of distant (2+ hour) car shows and did a lot of road trips with no issues other than running a bit warm on the highway at 70 MPH (3200 RPM), during the 110+ summer, with the AC on. If I dropped the RPM to about 2800 the temps would come back down and I could cruise forever.
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Joined: Jun 2018
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Right now the standard BF Goodrich tires. Fronts are the same, just not as wide. I just talked to the guy who rebuilt my 4.10s and he said it’s an easy decision - put on the 4.10s with a gear vendor and keep the TH400. I’m definitely leaning that way as the 3.23s seem a tad tall to expect good performance. He has a used Gear vendor with low miles ready to bolt on for $1800. I definitely keep hearing the TH400 is the way to go for the 455 torque.
W30
Joined: Feb 2016
Posts: 529
From: Cape Cod Ma
Right now the standard BF Goodrich tires. Fronts are the same, just not as wide. I just talked to the guy who rebuilt my 4.10s and he said it’s an easy decision - put on the 4.10s with a gear vendor and keep the TH400. I’m definitely leaning that way as the 3.23s seem a tad tall to expect good performance. He has a used Gear vendor with low miles ready to bolt on for $1800. I definitely keep hearing the TH400 is the way to go for the 455 torque.
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