Agage1 83 #1 Posted June 4, 2012 I just started a restoration of my 310-8. I've got the motor pulled it's k241s. I'm going to take to a machine shop soon to get it cleaned up. I was wondering if anyone has any tips for boosting the performance on these. I' d like to make fun to ride around with and maybe turn some heads but I'd still need it to some of the chores around the property. Share this post Link to post Share on other sites
Rooster 191 #2 Posted June 4, 2012 Almost any flathead engine can be "boosted" a bit without hurting its reliability or ease of use. It all depends on how much you want to do to it. You can make some minor internal modifications that are simple to do with simple tools. One such mod is to channel the top of the block, here is a simple example I made... This "cut-out" allows much more flow. Flathead engines suffer from a lack of flow. "Un-shrouding" the valves helps, sorry I do not have an example of that. Smoothing and minor reshaping of the intake port and valve helps. Do not get radical with anything, as over porting an engine can hurt its performance. If your willing to "compromise" the stock external look there are some gains to be made there as well. Most Kohlers need an Air filter upgrade, the stockers are restrictive. As well, the wheel horse "pipe" exhaust systems are a joke when it comes to performance! There are some minor cam mods you can make, however any time you modify the cam it will run differently, so I usually don't suggest those for "using" tractors unless I do the cam myself, lol, You want to add lift and a TAD bit of duration..but very little as adding duration will hurt your IDLE quickly!! 1 Share this post Link to post Share on other sites
specialwheelhorse 174 #3 Posted June 4, 2012 Believe me Rooster has it right on the money. You can polish intake and exhaust ports without changing there shape to much also polish piston top and valves till you can see yourself in them. And once again Roosters right on about the pipe exhaust junk. If you have to redirect your exhaust do it with smooooth internal tubing and only with looong gentle sweeps. Makes me Ill to see 90 degree pipe fittings on an exhaust system. Those that do can just flush about 5 to 10 percent of there power down the crapper. Just a nickels worth for now, we might as well do away with penny's JIM In Texas 1 Share this post Link to post Share on other sites
tunahead72 2,400 #4 Posted June 4, 2012 Is there any chance your block has "K301" stamped into the side near the PTO shaft? Share this post Link to post Share on other sites
Agage1 83 #5 Posted June 4, 2012 yes it is stamped k 301. is a valve job worth the money while its at the machine shop, and you dont think switching to a hot cam is worth it? and ive also been thinking about an eclectric fuel pump. will one of those micro pumps at the auto parts store work and if so would i have to upgrade the electrical system Share this post Link to post Share on other sites
tunahead72 2,400 #6 Posted June 4, 2012 I'm not an expert on these engines by any means, you're in much better hands with Rooster and specialwheelhorse, and a whole lot of other guys who know much more than I do. BUT, as I understand it, there was a period in Kohler history when the factory ran out of K241 blocks, and instead used K301 blocks to create the 10 HP engines they needed at the time. If I remember correctly, there's room in these blocks to bore them out in both directions to create a true 12 HP engine (and more if you go a little oversize). I don't know what other modifications would have to be made, but I know it's been discussed here in the past, I'll try to find a link for you. Share this post Link to post Share on other sites
Rooster 191 #7 Posted June 4, 2012 yes it is stamped k 301. Then it can be built to a 12hp ( I always forget about that!) is a valve job worth the money while its at the machine shop, Always!!!!! I would not put an engine back together without a good valve job! and you don't think switching to a hot cam is worth it? Not if you still want to do any "work" with the tractor! What kind of "chores" do you use it for? and ive also been thinking about an eclectric fuel pump. will one of those micro pumps at the auto parts store work and if so would i have to upgrade the electrical system I'll let someone else talk about the electrical system upgrades, but you really don't need a pump unless you really get radical. And even then I prefer a pulse pump, they are safer! Share this post Link to post Share on other sites
Rooster 191 #8 Posted June 4, 2012 you're in much better hands with Rooster..... Lol..Im not real knowledgeable on the Kohlers as I Am the Briggs...but I can make any flat head a little bit stronger. There are ALOT of guys here with better knowledge than me on building the kohlers specifically. Every engine has it's quirks! Share this post Link to post Share on other sites
tunahead72 2,400 #9 Posted June 5, 2012 Here's a link to some more information on the K241 blocks stamped with "K301", there's a link in there to more detailed information you might find useful: Share this post Link to post Share on other sites
Agage1 83 #10 Posted June 5, 2012 hey guys thanks for all the help. i just joined red square a few days ago and have already learned more on here than the past 3 weeks ive been tinkering with the thing. and sorry i just realized i'm in the wrong forum, thought i posted int he engine forum. i'm somewhat new on computers too. Share this post Link to post Share on other sites
can whlvr 993 #11 Posted June 5, 2012 what the others have told you is great advice,you can gat a better haed also,i recommend you go to brian millers pulling site and do alot of reading,he explains many things you can do and also sells parts and you can send him stuff,look in the links area and you will find it Share this post Link to post Share on other sites
