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TR4/4A Performance cam

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Too bad SBC parts don't fit on a our engines, we would have all kinds of cool bits.
 
So if I was just itching to spend money and I want a street car not a race car the big bore 89mm kit would be a better investment? Or would the benefit from that only come from doing other things as well. Another words if choosing between a street cam and a big bore kit which would yield the best result?
 
First of all I have no idea of the cost differential between the two alternatives. However the benefits weigh heavily toward the big bore side. Better performance across the board (slightly more hp and torque everywhere). Down side, may need a better grade of fuel and/or slightly poorer mileage. Nevertheless, don't expect miracles from what amounts to a few more cubic inches. Unlikely even a seat of the pants increase in performance will be felt/measureable.
 
Absolutely the big bore kit. Increasing CI helps torque, power and drivability. Once again...a cam just decides where in the rpm band you want that torque to “come in”. Cam is a compromise while CI improve everything.
 
According to my calculations going from 86mm bore to 89 mm bore gives a 7% increase in displacement (pi R squared and all that) plus factor in a compression increase, you may be getting 10% or so increase in HP and torque. If you are replacing the Pistons and liners anyway it is pretty much a no brainer to me.
 
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