wheelhorsepuller 1 #1 Posted November 20, 2006 Since I had to replace the blown engine in my '73.. I thought I'd clean up inside the engine before I put it in the tractor.. I stared by porting the intake and exhaust ports... I mainly cleaned up the casting marks, removed all the ridges, and gave it a bit of a polish... I then rounded the lip in the head where the mixture slopes down to meet the piston... I also polished around the valves in the head and tried to unshroud the valves to help flow.. The deck surface got polished like a mirror to help to keep the carbon from building up again.. The valves got a thorough cleaning and since I now had extra valves to use from the blown engine.. I used the one with the least amount of wear on the valve stem.. I lapped the valves and put her back together.... Share this post Link to post Share on other sites
Sparky-(Admin) 21,352 #2 Posted November 21, 2006 Are you running stock size drive pulleys? I have a C-105 that I transplanted a 12hp Kohler Magnum into. This will be my pulling tractor if I get it all done by this spring. Anyway, I cant decide if I need to increase my ground speed for the pulling tracks or not. I have a stock 4" pulley on the motor but have a 5" that I could put in its place to pick up some ground speed. The stock pulleys get ya up to about 6MPH. Dont know what it would be if I swapped the pulley to a 5". Any thoughts? Mike Share this post Link to post Share on other sites
wheelhorsepuller 1 #3 Posted November 21, 2006 SInce you have more power I would think it might help... But I would be more tempted to put a bigger pulley on the tranny first... That's what the guys that flat track race lawnmowers do... and they go almost 50mph It takes more power to turn the bigger pulley on the engine.. Share this post Link to post Share on other sites
whchris 5 #4 Posted November 21, 2006 to increase speed on a tractor you would increase the engine pulley and decrease the transaxle pulley thus resulting in high speed with low torque. for pulling i would think that a slower ground speed with increased torque would be your best bet since its distance of the pull not the time of the pull that counts. try pulling things around like your pickup (with someone in it) or a sled change pulleys see what works best for you. tire pressure is a big thing too. try this site for engine mods, http://members.aol.com/pullingtractor/engine.htm Share this post Link to post Share on other sites
wheelhorsepuller 1 #5 Posted November 22, 2006 I got it backwards... oops... I meant to say smaller on the tranny to speed up the tractor..... thanks for pointing it out... I'm thinking of doing just what you said to help learn how the tractor will behave.... I've been to that site.. great info.. Share this post Link to post Share on other sites
wheelhorsepuller 1 #6 Posted November 16, 2007 Well the engine went to the machine shop.. I had the tab on the governor break so I took the whole engine apart for a rebuild. I had it overbored .010 for a new piston, went with .010 under size new rod, 3 angle valve job, milled the deck for zero deck height, milled the head, and reground the crank The wingnut who did the last rebuild milled the deck on an angle. luckily it took only .005 to make it flat.. it just gives me zero deck height which is great for a little more power.. I'll post pics of it when it comes back next week. Share this post Link to post Share on other sites
nylyon-(Admin) 7,294 #7 Posted November 16, 2007 Is this the same engine you had Supercharged? Share this post Link to post Share on other sites
wheelhorsepuller 1 #8 Posted November 16, 2007 Ya.. I pulled that off.. I couldn't flow enough air through the engine.... I would actually stall out the pump and make the belt squeal. I would need a smaller pump that flowed less air. It made so much pressure it ballooned the hat over the carb .. Share this post Link to post Share on other sites
Rollerman 290 #9 Posted November 16, 2007 Please post some pics of your blower setup so we could see it in more detail! What did you use for an air pump? Stephen in northern IN Share this post Link to post Share on other sites
wheelhorsepuller 1 #10 Posted November 16, 2007 The smog pump is from a 1991 Dodge pickup with a 318. The only thing I didn't like was that it draws air from behind the fins. The GM one have an air intake pipe that you can put a filter on so that you don't need a air filter at the carb. This shows how I mounted the smog pump. The pulley is from a K181 from the 60's that used a generator/starter The bar on the top is attached to two long bolts to the bottom of the engine. This keeps the head and cylinder from separating from the block with high boost. Share this post Link to post Share on other sites
nylyon-(Admin) 7,294 #11 Posted November 16, 2007 It looks like you are overdriving the pump making it push too much air. Maybe you could add a pulley to the flywheel to underdrive it. Share this post Link to post Share on other sites
Rollerman 290 #12 Posted November 16, 2007 Thanks for posting the picks in better detail "puller". I have heard of this setup before, but never seen in the flesh & not with a Carter N carb. I beleive a Keihn or Mikuni was used on the setup I was told about. Do you think this setup would create enough pressure to blow the cylinder head off? Or you could do this...... I seen it this summer at my locat garden tractor show but don't remember watching it run. Stephen in northern IN....bad ideas in my head now :D Share this post Link to post Share on other sites
