HS40 high performance parts?
- Thread starter hotrodbutcher
- Start date
Kinda feel like I'm wasting time with some of the posts I do. As previously posted,
Dyno 245 cam for the OHH engines.
ARC 6282 Billet Rod for the 5.5 OHH engines.
Dyno AN-001 18 LB valve springs for the Briggs Animal.
Briggs DCSH103 valve keepers for the Flathead.
Briggs DCSH102 lower valve spring retainers for the Flathead.
@delray did one as well, and if he sees this can link his video or amplifying information.
Dyno 245 cam for the OHH engines.
ARC 6282 Billet Rod for the 5.5 OHH engines.
Dyno AN-001 18 LB valve springs for the Briggs Animal.
Briggs DCSH103 valve keepers for the Flathead.
Briggs DCSH102 lower valve spring retainers for the Flathead.
@delray did one as well, and if he sees this can link his video or amplifying information.
ok hotrodbutcher, for making it just bit quicker and higher rev's. I would look into purchasing a newer cam out of a 5hp flathead or a ohh block. they will come with a compression relief steel cam. some also use the plastic cams. stay away from them. steel cams you will be able to run a better valve spring that can handle the higher rev's and not chewy up the plastic cam. with the compression relief you be able to advance the timing little and not worry about any hard kick back when pulling the engine over. also can purchase a better retainer/keepers that will give you a positive lock(automotive style). little porting in the bowl's and good adjustable idle/main jet carb for a hs-40 or 50 will work or better a 19+mm carb. good header too. stock factory rupp header will work or Robertson torque tubes. this will pull good up to 4500+ rpm's. if you want to go little more crazy and spend more money …etc.. and turn more rpm's. then the 245 will put you in that ball park. only problem with building a higher reving motor there is a ton more mods that need to be done.
use dave's part numbers above,but if you go with the stock newer compression relief cam. you will want the animal #16 pound springs part number 26826 from dyno-cams. if you do need to rebore the block oversize? then I too would recommend going with the newer hs-40 piston and rings(thinner style rings).
use dave's part numbers above,but if you go with the stock newer compression relief cam. you will want the animal #16 pound springs part number 26826 from dyno-cams. if you do need to rebore the block oversize? then I too would recommend going with the newer hs-40 piston and rings(thinner style rings).
Thanks Delray. I'm a mechanic by trade and I know most of the "tricks", I'm just not familiar with where to find the parts for these motors. I've got clone 212s that I can go across town to GoPowerSports and get parts for, but nothing local for my old HS40. Eventually it will be a flat track racer here in TX at the T.O.M.B. races that are everywhere.
Just watching the video makes me not want to install them there parts....
Dyno 245 cam for the OHH engines.
ARC 6282 Billet Rod for the 5.5 OHH engines.
Dyno AN-001 18 LB valve springs for the Briggs Animal.
Briggs DCSH103 valve keepers for the Flathead.
Briggs DCSH102 lower valve spring retainers for the Flathead.
Seriously if you want a quick HP gain without a lot of money or energy (and hard to find parts or hard to pull start), i suggest a slide carb. I use 16mm slide carbs, and with a new air filter, it's $20. It really gives a nice low and high end boast. Looks cool too. And if for some reason you don't like it, it's easily reversible. cfh
Dyno 245 cam for the OHH engines.
ARC 6282 Billet Rod for the 5.5 OHH engines.
Dyno AN-001 18 LB valve springs for the Briggs Animal.
Briggs DCSH103 valve keepers for the Flathead.
Briggs DCSH102 lower valve spring retainers for the Flathead.
Seriously if you want a quick HP gain without a lot of money or energy (and hard to find parts or hard to pull start), i suggest a slide carb. I use 16mm slide carbs, and with a new air filter, it's $20. It really gives a nice low and high end boast. Looks cool too. And if for some reason you don't like it, it's easily reversible. cfh
You "definitely" got what you paid for. LMAO!
@hotrodbutcher something I may need to explain in that video, that was the first start after the rebuild. It was a points engine, so required me to time it, unlike the newer engines which use a solid state mag set at TDC.
Also, the Dyno 245 cam does not come with a compression release, so the engine has to be pulled past the compression stroke, just like any other small gas engine equipped with a cam that isn't using any CR. Not for the weak of wrist.
@hotrodbutcher something I may need to explain in that video, that was the first start after the rebuild. It was a points engine, so required me to time it, unlike the newer engines which use a solid state mag set at TDC.
Also, the Dyno 245 cam does not come with a compression release, so the engine has to be pulled past the compression stroke, just like any other small gas engine equipped with a cam that isn't using any CR. Not for the weak of wrist.
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More info on Tecumseh slide carbs for HS40 and HS50 motors can be found at
https://www.oldminibikes.com/forum/index.php?threads/new-tecumseh-hs40-carb-s.155806/page-3
Again i highly suggest trying this slide carb modification before you split the case and spend $100-$200 for a new cam and connecting rod. It's worth trying it, given the price and ease of the modification. Also the engine won't require you to start working out with weights to start it... cfh
https://www.oldminibikes.com/forum/index.php?threads/new-tecumseh-hs40-carb-s.155806/page-3
Again i highly suggest trying this slide carb modification before you split the case and spend $100-$200 for a new cam and connecting rod. It's worth trying it, given the price and ease of the modification. Also the engine won't require you to start working out with weights to start it... cfh
I don't think your going to be passing any 212's with a stock cam in a hs-40 engine. even with all the mod's done to it. you might be able to keep up with a hs-50 bored out to it's max and a 255 dyno cam in it and make it run on alky and if you get that far with a motor? then you need to have the right bike and drive train and the most important thing. A real good rider. lot of times it's not all about the motor making you go fast. from what videos I have seen on T.O.M.B racing you would really need a bad ass correct built big block H motor to keep up with the clones and pass them too.
the best that I can gauge my hs-40 build https://www.oldminibikes.com/forum/index.php?threads/hs-40-build.161335/ against a 212 with just a jet kit and header, at 125 ft I could beat them on clay track. I had a chance to run up against some on a Friday night grudge racing. now if they had a full built 212 that would be a different story.
by the way what are the rules for racing at your tracks in texas. do you have classes for just flatheads or do you have to run against the clones?
the best that I can gauge my hs-40 build https://www.oldminibikes.com/forum/index.php?threads/hs-40-build.161335/ against a 212 with just a jet kit and header, at 125 ft I could beat them on clay track. I had a chance to run up against some on a Friday night grudge racing. now if they had a full built 212 that would be a different story.
by the way what are the rules for racing at your tracks in texas. do you have classes for just flatheads or do you have to run against the clones?
delray, we do have classes...two actually. Stock which means predator 212 with jet, air cleaner, and pipe mods, no internal mods and governor must be intact and functioning. Second class is Outlaw which is "anything goes" with regards to the motor. All classes are limited to 10 inch or smaller wheels. I think there is talk of some other classes that will give the flatty guys some play, but for now, this is how it stands.
This is what i'm working with for my flat tracker. '71 Rupp hustler with a couple of swingarms so I can do an extended one like I saw on one of the builds here. (need to hear more about that metallic swingarm bushing) Right now stripped down for de-greasing, metal repair on the seat pan, blasting and powdercoating
