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I just got a free 1970 olympique with a 399 with 818 miles. The sled came with the owners manule, acutally in pretty good shape, so I flipped through a little bit. I found that the 399 in the olympique was rated 24 HP. Then I saw the T'NT was rated for 30 HP with a 399 of the same bore and stroke as the olympique. The only difference I found in the manule was the compression, the oly 8.75:1 and T'NT 10:1. I found online the carbs were different too. My question is how, if possible, can i rebuild my olympique motor to the T'NT spec 30 hp? I figured on a set of pistons and a new carb, and I'll probly just use a mikuni instead of trying to hunt down a tilloson. Anyone see any problems with this? Will the timing have to be changed to acomedate the new pistons?

*i plan on installing a complete gasket kit as well as the new pistons and carb on my install.

thanks alot
 

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I am Spartacus
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You should be able to do it by just installing the domed pistons and the carb. You wouldn't have to change the timing, because it'll still be sparking at the same time, but with more compression. You'd have to see if it knocks when you run it.
 

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why change anything, you never know the difference, it was all in the carbing and exhaust.
 
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