Which Exhaust is Best for Low-End Torque?

1973x75 said:

What’s a BOT?

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Like a ROBOT, but only 7oz.

Triton Thrasher said:

E3275 is the Thunderbird ramp cam.

E3325 is the T110 cam.

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E3325 is the ramp cam which was used in the 1958 Thunderbird, which had the wheel stamped on the crankcases.. In a pre-unit Bonneville, there was an E3134 race cam in the inlet and a T11O cam on the exhaust. Unit construction Bonnevilles were similar, except for the Thruxton. We actually imported the E3134 cam with the points extension - it had a different number. It improved performance a lot. In those days getting race cams was not easy. A Commando cam has similar timings to an E3134. If you need more docile- a milder cam on the exhaust will do it.
If an Atlas is not sportier than a Commando, why was the Commando created ? It was the era of Duffle coats and desert boots , Mods and Rockers - the market had changed. People were buying Vespa and Lambretta motor scooters and bubble cars. The 1950s were totally different. I like Commandos, but I would never rubber-mount the motor of a motorcycle. It was done to some two-stroke race bikes in Australia in the 1970s, because the frames were cracking.

I had a 1958 Thunderbird which had E3325 cams, and the wheel stamped on the cases. It was quicker than it should have been, so you might be correct. I bought it from a cop - somebody had been killed on it. It had been ridden into a brick fence.

acotrel said:

E3325 is the ramp cam which was used in the 1958 Thunderbird, which had the wheel stamped on the crankcases.

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That’s not true.

1973x75 said:

What’s a BOT?

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Ai or is it AL?, something like that. Ignore option works a treat though.

concours said:

Pretty sure this is a BOT post selling exhaust parts. Click on the hyperlink.

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thanks