129 MAX Speed
 

Tomorrow is the annual neighborhood tractor race [all stock - I think] and was curious if there is anything easy that could be done to eek a little more speed out of the old 129. Granted the max speed of the tractor is controlled by the hydrostatic trans and maybe this is more so psychological, but was looking for any edge I could find. [the one neighbor has a big ol' JD] I've seen posts to remove the sponge around the air cleaner and have since put some additional air in the tires and removed the deck, hanger and wheel weights. Was considering buying higher octane gas but thought I would throw it out to the experts here. Any suggestions, ideas, ro comments would be greatly appreciated.

thanks in advance
Rob

The tallest tires you have will increase speed.

have fun :beer2:

Speed up the engine to 3800RPM

I had 26x12x12 ag tires on my 147 for a tractor pull and they made it a little faster then the stock 23x10.50x12.

Better Gas (Higher Octane Rating)
 

should make a worthwhile improvement in the way the motor runs (Higher Octane = better combustion ). You can usually buy Av gas (Aviation Fuel ) at the airport or Racing gas from a station that carries the premium stuff. Google is your friend. Good Luck.

You can basically run any grade gas you want it's not gonna change engine RPM's . Gov is set at 3600 RPM's and that's all there is. You can change Gov settings but I wouldn't go more than 2 or 3 hundred RPM. :bigthink:

Sorry, but I have to disagree with this. Higher Octane in a low compression engine like you have in a Cub will actually give you less power. High Octane is used to control detonation in high compression engines.

As far as engine mods like air cleaner, gasoline, timing, etc., short of adjusting the governor, that is the bottom line.

Bigger rear tires (gearing) would be the safest, easiest change short of adjusting the governor.

If you're running around any sharp corners, I just wonder if leaving the deck on the tractor wouldn't be a good idea to lower the CG? If you're on dirt, wouldn't skinny front tires dig in a little better in the turns vs using wide ribbed tires?

Just guessing here. I never raced a lawnmower.

LOL, you should have looked into this like two weeks ago, not at 9pm the night before needed.
Just get on it and stay low.

:biggrin2:

Not really better combustion in this application. Avg gas is 100-110 low lead which is most common by far. Its not really better at combustion or has more energy content one vs the other, it depends on the use IE what motor it is burned in that's the difference.. Gas burns either way. The lead has a higher octane rating which is more resistance to detonation on high compression or boosted engines of which aircraft have. This higher CR or boost give more performance no really the gas persay.

The by product of the lead is it created a layer of lead on the valve seats to cushion the valves and it retains its octane for years IE it doesn't go bad. I have left avg as in a motor unstarted for 2 years and it started right up.

The bad is avg gas is expensive now $5-7 a gal normally some times cheaper. Oh and lead will kill you well over time.


EDIT: Any one ever put some spray or a small turbo on one of these motors? I guess it wouldn't matter on a hydrostat as it only spins x speed to get X pressure?

Beside bigging up the rears, more pressure in front tires if handling is not factor. Reason...less roll resistance.

The purpose of lead wasn't to cushion the valves..... it was to lubricate them.

When you say "spray" I assume you mean nitrous? No.... it would blow it apart. A turbo? No, it would blow it apart... motor is not meant for boost unless you beef it up.

I'm not sure you understand the principals of the hydro trans. It would matter, as in X speed. Pressure is regulated, so it won't change with speed. Run the hydro faster, the output will be faster, just like any other trans. Pressure doesn't really affect speed. It's just a hydraulic pump driving a hydraulic motor.... faster input = more flow. More flow= more speed.

Exactly the lead formed a barrier that protected the valve seat. But lube or cushion same thing with the aspect of valve seat protection and what I was specifically talking about. It forms a protective layer to protect the head valve seat area or it would recede (or whatever your specific term you want to post for it lol) into the head over time casing several issue. Hence the use of hardened valve seats on all non-leaded cars in later years because they lacked the lead in gas. And the seat area





Well duh yes beef it up or else it wouldn't be worth the effort to run a few psi or small shot of N2O and not gain noticeable power.

Quick google search brings up some performance parts and even billet head and decent looking bottom end parts for K motors.

And surprisingly a blow err supercharged K motor. :biggrin2:

http://www.ihcubcadet.com/forum/messages/106/13924.jpg


Oh and If money is an issue then neither of the power adders is recommend. lol






Correct haven't ever messed with one. Hence the question mark at the end of the sentence. How else to learn then as to ask questions and research. Point was if motor makes more HP can the Hydro trans actually put that to the ground in the form of speed given the topic at hand.

As stated numerous times here, several different ways, the governed engine speed is the determining factor in how fast that tractor will run under NO LOAD.

If you're running a steep hill, pulling a load or otherwise can't bump the governor, twice the horsepower will not make you run any faster.

Whatever you say. It's not worth a debate.


There are a few people who have done some "different" mods. But it isn't worth it or the pullers would all be doing it. For the most part, no. It won't handle it. I'm aware of all the performance parts available.


A hydro is about 80% efficient. So.... yeah, if you increase power it will increase power out. But only at the rate in which the hydro is efficient. No, if your next question is can you make them more efficient. That's just how it is. Oh sure, you might be able to increase it a couple percentage points, but not anything like the switch to a gear drive which is about 97% efficient.

I'm a little late getting here and this would be difficult to do with the fender pan on your 129...

I saw some pictures one time several years ago of a fellow at a similar race who put the big diamond tread wheels and tires from a lo boy on an Original to increase his ground speed.

It looked kinda dangerous to me.

Bingo!:NailHead: It amazes me how many misunderstand this. The partially burnt fuel stays behind as carbon build up, thus increasing compression, making it ping when don't use high octane.

It costs more, it must be better.:biggrin2:

Edit: I didn't see the second page. Need more :coffee:

The way they used to explain it to us was:
Low octane fuel burns fast in the combustion chamber and it is possible to have 2 flame fronts in the combustion chamber due to heat/compression, and when they meet/collide during compression, it produces knock and piston destruction
( BTDT)
Higher octane burns slower allowing for more controlled burn with no knock or engine damage.
Tetraethyl lead increased octane and lubricated the valves/seats for longer life.
@ least that is what they taught us back in the day.

-------But lead caused Cancer in the state of Mexifornia so it was a removed:biggrin2:

I agree 100% with this statement, I learnt it well in my intro to internal combustion engines class while I got a degree I don't use... In modern cars, higher octane could actually lessen performance because the computers will adjust things improve emissions.

HOWEVER

Why does the owners manual say to use 89 Octane or above? Was much lower octane available back in the ole days that someone may have used TOO low octane?

I'm not arguing against the uselessness of higher octane in a low combustion engine, just curious why IH would say to use 89 Octane?

High octane won't lessen performance you just waste money in a engine that is setup to run on 87. Most manufactures have mult timing tables built in the tune. So if the motor is spec'ed to run on 87 and you run 93 then your just wasting money as it will run the same. No some oil companies do have additives they add to the premium that does work to clean the valves and such. But actually its a waste of money too as most newer cars and trucks are direct injection now, so the intake valve never sees fuel anyway so the additives can't clean it.

If the motor is spec'ed to run on 92+ then it most likely a high compression engine 10:1 or better. If you run 87 in it, then when it "pings/knocks/detonates" (that should cover everyone's terms here if not google it lol). Then computer pulls timing and it defaults to the low oct timing table for a set time or till it notices higher octane and you have less power because it has less timing, that's it in short vs typing specifics out for the people that love arguing here. :rolleyes:

Gasoline direct injection is brand new to the market in the standard US cars. Gm just began using it in thevery last few years.

All the info some of you guys are talking about is related to computer controlled emission engines, which has nothing to do with the question at hand.... an old Kohler motor.

I think this thread is pretty much dead anyway as the OP got some "info" and "race day" has came and went....

Incorrect. DI has been 10+ years in the market for GM and isn't brand new. GM has had DI since 2007. DI has been in Pontiac, Saturn, and Cadillac etc for almost 10 years. Chevrolet began in 2010, so I guess that is a standard car.

So its more than a few years.


I just answered to correct some miss information a member posted to maybe help inform him, seems its ok for others to correct people with there knowledge in various threads. Whats wrong with that?

And actually the member had asked a question related to the topic at hand in his post. So not sure why its "dead"? If the members question is relative to the topic and may very well help another member out if someone is trying to do the same thing.

I suggest you look at a Kohler service or operator manual. Both say use clean fresh unleaded fuel that has octane of 87 or higher.

I was taught that the lead additive was use as a cushion/valve lubricated the valves/seats for longer life.

It is not used as a octane boster.

You are not the only one.

Interesting......Most of the fuel companies in my area have additives to clean valves and injectors in 87 octane. I see the same additive promotion on the pumps when I'm on the road.

I didn't look specifically at the kohler manual, but did look through the QL Owners manual here, pg 9

http://www.onlycubcadets.net/forum/s...ead.php?t=4670

My mistake, it doesn't say 89, it says 91 or higher for unleaded.

Again, I'm not arguing that it's needed, just curious why IH would suggest it. It only stuck out because I know it's not really needed. Since this thread veered towards octane debates, I thought I'd ask.

Next I'm going to get opinions on hydraulic fluid :ThumbsUp:

Yeah depends on the company. But interesting enough all base gas comes from same distribution point and they add the additives for each station when they fill the truck tanks. Had a buddy that worked at a yard for number or years. He also said that one of the stations did have there own tanks just for their own gas out of their refinery, I think it was Shell. But its been a long time ago.

Interesting read:
http://www.todayifoundout.com/index....d-to-gasoline/

Lead added to gasoline was initially for it's anti-knock (detonation) qualities.

Nothing to do with valve/seat lubrication at first offering.

Reference:

http://www.petroleumhistory.org/OilH...ges/knock.html

Shell, BP and Marathon are 3 big companies that come to mind.

You are correct about first offering.

The companies that built/design engines found out that they could use a cheaper material in the exhaust valve and seat when using lead. Cheaper material means more profit/lower cost of a product.

Getting back to making the 129 go faster........just wondering if the tractor race is a drag, circle or road course? There's much to be said about how you drive the tractor.

Thanks you al for the great ideas albeit well above and beyond what was possible [at least for me that is].

Just to close the loop and as a quick update, the race was all road, for the most part straight, but with a somewhat significant hill. Just to sway the weight odds somewhat more so in my favor, I let my 89lb daughter drive [who BTW actually got into it and even broke out my old bike helmet after she stuck on the number 11]. Anyway, what I'm calling her blocking strategy [others might call just bad driving] paid off and she rolled across the line in second place. If the race was all stock, she probably would have come in first. She now wears her paper Burger King Crown proudly. Thanks again for all great ideas and we'll need to start to prep earlier for next years! bigthink:

Congrats! And at least it was fun!

Well now for next year, if it is on the same course, you might want to go with not so tall and more smooth tread tires.
Take advantage of that "significant hill" and if there are a lot of turns, even better.
Does not sound like a course where "top end" is the favored goal.