D15 Puller

Does anyone have a D15 puller. I want to make a little more power with ours. Is there a cam available for the 160, how much can I mill the head for more comp. I am not going to go as far as stroking or overbore. I will do some carb mods. What gov spring and weights would be good. I am running 13.6x38 tires. I will have to run it in the 4500 class. When we stripped it down and built a light seat for it, it still weighed 3575 with my dad on it and he is 150lbs lighter than me.

One inch diameter carb venturi would help from a 175 tractor, or a larger carb altogether. You are pretty well maxxed out on a G-160 engine without tearing it down and making custom parts. Cylinder head is flat-------no compression gain without changing pistons or crank stroke or conn rod length.

   I'm just thinking out loud here, cause I've never fooled with an engine that has the combustion chamber on the piston. I wonder if a person could have the block milled and liner pockets relieved and bump up the compression ratio to produce HP ? You would then have to mill the top of pistons by same amount. Don't have any idea howmuch to take off,,,but I'm bettin, some of the pullers are already doing this,,,!!
I dis-assembled a "B" some time ago, and was pleasantly surprised at the very efficient lookin chambers in the head. The chamber design Looked like something, a good cylinder head porter could re-work and produce some good HP.