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Old 01-01-2013, 12:54 PM
DanielC DanielC is offline
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After glancing at this thread off, and on, and the p*$$*ng match going on, I have a slightly different idea.

Ignore peak horsepower. You want torque.
Peak horsepower is fine, if building a NASCAR engine, they spend time at peak RPM, where peak horsepower is important. Even a quarter mile car, used exclusively for drag racing has to pull through the RPM band, and does not spend that much time at peak RPM.

This is a dually truck for towing a two car trailer, from what I read in the first post of the thread. Reality is the engine will rarely hit 4,000 RPM. Most of the time it will be below 3,000 RPM.

Stroking it is good, it adds torque down low, it makes the engine less sensitive to radical camshafts.

There is a lot of talk about high dollar high flow heads. Why? How difficult is is to fill a cylinder on an engine running 2500 to 4000 RPM?

So, what experience do I have with towing, and big block engines? Not much really, unless you consider that for many years, I showed horses, and used a 1966 Ford F-250 to pull a four horse steel trailer, and a camper to horse shows, all over the Pacific Northwest.
I took the 352 that came in the truck, put a 428 crankshaft in it, making a 410, and with a four speed truck transmission, and a 4.10 rear axle ratio. Sometimes I would tow with the camper, sometimes without. Without the camper, and four horses, maintaining 60 up a 6% grade, in top gear was no problem. And here is the bonus. driven carefully on the freeway, below 60, the truck would get about 14 MPG.
The engine has a more or less stock 600 CFM carb on it. A mild RV cam, Stock exhaust manifolds, dual exhaust, but no "X" pipe. About the only high performance mod done to the engine was a single plane Edelbrock torquer 390 intake manifold, because the original manifold was only a two barrel manifold.

Now, if you really do want to race, that is another thing. But if it is really a heavy duty tow vehicle, build for torque. Do not worry about horsepower, you will hardly ever get to that RPM anyway.
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