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Cub 128 "Precision Guesswork" build HELP!!!


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#1 venisonslayer128 OFFLINE  

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Posted August 12, 2011 - 10:14 PM

for starters i'm 19, been pulling antiques since I was 9.. Pulled a Prostock for 2 years until the sled operator started putting the brakes on at 150 feet to keep us from winning again... i do everything pull related not machine related so here we go..

Cub Cadet 128 Kohler K301 the only stock class rule is 3800 RPM.. so I need valves valve springs, piston, rod, cam, crank machined, block machined and head machined. suggestions? Midwest supercub has 101 pistons and rods and thats just pistons and rods!!

#2 NUTNDUN OFFLINE  

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Posted August 12, 2011 - 11:33 PM

Midwest, Vogel and Brian Miller are the main ones I can think of to get stuff from for the engine. That is a pretty open rule for stock class with the rpm limit being the only thing. You will have a good bit of money tied in to the engine. You might be able to have the crank offset ground for a little stroke. The rod would need machined also. I think I would go for the new piston/rod and valve/valve springs and have the block decked to raise compression a little and be done at that. Unless the motor needs punched out anyway to clean up the bore.

#3 venisonslayer128 OFFLINE  

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Posted August 20, 2011 - 08:20 PM

do you have any suggestions on which cam to use or how much to mill the head and deck the block?

#4 Rick Brumback OFFLINE  

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Posted August 21, 2011 - 09:54 AM

Okay,when the head is shaved all you are doing is having a raised lip removed,be sure the hhead has been polished and is smooth when its done.you can also have the cooling fins on the flywheel shaved to lighten it some.Decking,is something I havent had done so I really cant help you with that,sorry.In my 12 hp kohler I run a 18 hp cam,my motor has a .30 over bore with a hi dome piston.

OK, after some reading,all decking a motor does is increase the distaNCE the piston comes up,you may increase hp 1 to 1.5 hp.

Edited by Rick Brumback, August 21, 2011 - 05:10 PM.


#5 venisonslayer128 OFFLINE  

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Posted December 03, 2011 - 08:24 AM

I watched the club I want to join and really theres nothing too rediculas pulling in the stock class even with the rules as loose as they are.. a lot of hodge podge slapped together hunks of iron.. As I have fallen in love with the Red Power... er Yellow and White power and began collecting them id never let half that stuff leave my shop nevermind pull with it.. on that note back to pulling.. i have found boat loads of information but everyones ideas seem to be different with the big pro stocks it was simple, lower compression giant turbo giant injectors giant manifolds.. suck air in blow it out.. I looked on websites and all kinds of stuff through the states and everyone wants titanium this and billet that.. why do gas engines have to be so complex!! i have heard of using an 18hp cam so i will use one for sure Do you use siffer valve springs or anything else? ive also heard of piston pop where you machine the head and jam a big rod in and have the piston pop out of the cylinder big stroke more torque right?

#6 junkman1946 OFFLINE  

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Posted December 03, 2011 - 09:13 PM

I must have missed this thread back in August. You said your limited to 3800 r.p.m.? If that is correct thats only 200 r.p.m. over factory governed speed.
All that machine work,special valve springs,etc. is going to do only one thing for you.
EMPTY YOUR WALLET !!
Take your 301 Kohler, clean it up inside, put in a set of Chevy Points, copper head gasket, maybe rework the carb a bit, and go Pullin. Your biggest advantage in the Stock Classes is Ground Speed and Traction.
I've got a window full of trophys for A-Stock with a 1250 C.C. with 23-1050- 12 tires , 23-24 gears,and a 13 tooth drive gear.

#7 venisonslayer128 OFFLINE  

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Posted December 05, 2011 - 04:25 PM

yeah I guess i was just flooded with information at the start of this build.. i mean theres so many products and not a lot of information i just want a reliable strong engine so I can focus on setup. I watched a 128 in 1,100 stock and i noticed from expeirence stock first gear looks too slow while stock 2nd gear is too fast is there a 1 1/2 gear i can put inplace of 1st?

#8 skyrydr2 ONLINE  

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Posted December 10, 2011 - 08:15 AM

I must have missed this thread back in August. You said your limited to 3800 r.p.m.? If that is correct thats only 200 r.p.m. over factory governed speed.
All that machine work,special valve springs,etc. is going to do only one thing for you.
EMPTY YOUR WALLET !!
Take your 301 Kohler, clean it up inside, put in a set of Chevy Points, copper head gasket, maybe rework the carb a bit, and go Pullin. Your biggest advantage in the Stock Classes is Ground Speed and Traction.
I've got a window full of trophys for A-Stock with a 1250 C.C. with 23-1050- 12 tires , 23-24 gears,and a 13 tooth drive gear.

What about the clutch ? did you do anything else ?

Edited by skyrydr2, December 11, 2011 - 01:49 PM.


#9 venisonslayer128 OFFLINE  

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Posted December 13, 2011 - 11:21 AM

I am using a Midwest complete clutch setup building my own front axle to give it rake fabricating a steel grille and nose instead of cast and obviously stripping it of impliment attachments i'm buying a new set of firestone ag tires and cutting them to my own liking.

balance is everything when it comes to pulling so it'll be a lot of test and tune my first year with these. things like tire pressure and gear selection make a big difference as well if you had the CC in 3rd it won't do anything. if the CC is a hydrostatic dont bother.

there were two 128's in the stock class and they placed in the top 10 out of 30 on a sandy track so i am confident it'll pull

#10 Rick Brumback OFFLINE  

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Posted December 15, 2011 - 11:23 AM

On the front end,i went with fiberglass from midwest and alum hood from midwest.4 puck midwest clutch, my motor has a 30 over bore,pop up piston,decked,portrd polished balanced.head shaved,dart carrier and ring gear,fine spline rear end by the way.flywheel fins shaved,had to install a high speed fan for cooling after that.pitbull 26x12x12 rears on douglas wheels.adjustable hitch,weightbar on the front slides and is adjustable.midwest wheelie bars,lakota exaust pipe,gm points,bosch blue coil e3 plug and a radiator overflow tank for fuel,small electric fuel pump.battery is under the seat.This is allowed to pull 12 hp STOCK class according to NQS RULES which my club uses.

#11 skyrydr2 ONLINE  

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Posted December 15, 2011 - 12:17 PM

On the front end,i went with fiberglass from midwest and alum hood from midwest.4 puck midwest clutch, my motor has a 30 over bore,pop up piston,decked,portrd polished balanced.head shaved,dart carrier and ring gear,fine spline rear end by the way.flywheel fins shaved,had to install a high speed fan for cooling after that.pitbull 26x12x12 rears on douglas wheels.adjustable hitch,weightbar on the front slides and is adjustable.midwest wheelie bars,lakota exaust pipe,gm points,bosch blue coil e3 plug and a radiator overflow tank for fuel,small electric fuel pump.battery is under the seat.This is allowed to pull 12 hp STOCK class according to NQS RULES which my club uses.

Holy smokes! So it just looks stock LOL!
Dang, that's a lot to get and do just for stock! Isn't NQS, National Quarter Scale ?

#12 Rick Brumback OFFLINE  

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Posted December 15, 2011 - 01:42 PM

yes it is national quarter scale.My tractor isnt an alky motor,yet.NQS rules reauire all nqs series tractors to be on alky,not gas.52 inch wheelbase,tractor weight in at 750 pounds without me.The engine mods are legal for stock class in my club,different cluns,rules tend to change a lot.Check with your local club,or the club you plan to pull with and get their rules concerning engine mods ect.

#13 Randy Littrell OFFLINE  

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Posted December 16, 2011 - 07:21 AM

When pulling in stock class with 3800 rpm limit, the important things are tune, compression, weight, and tire presure. No need to spend money on parts that only help at high rpm.

Use a head with the plug over the valve instead of the middle and have it milled .040. That one thing will make a big difference. If you have the rod inserted for a bearing you could pop it up .010 as well.

23" tall tires work well with stock 19 tooth second gear and 26" tires work well with a 16 tooth second from a original or early 70/100. If you can afford to do a 2-3 gear swap you can get a 19-20,, 20-21, you get the picture. With a 2-3 gear swap you will be able to change with track conditions.

You need the ability to put weight out front, underneath right in of the rear tires, under you seat, and even right behind you. It will take you a whole season of more to really figure out your tractor.

You want enough weight out front so that you have to lean way back early in the pull, and when the sled starts pulling you down that weight out front will keep you from over rotating too early.

Don't forget to HAVE FUN!!!!!!!!!!!!1111






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#14 venisonslayer128 OFFLINE  

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Posted December 17, 2011 - 03:36 PM

im running 26 12 12 cut ag tires and 6's up front with an axle im in the process of building.. can anyone give me an idea of what a cub 128 would weigh? obviously i want to make the #800 stock class but i have no idea what it weighs at the moment
thanks for everyones advice. as i said I have 10 years of serious set up and running expeirence in antiques and pro stock pulling.. with 3 straight club championships but I have zero with Kohlers or cubs in general. its new ground for me..i'm really enjoying the build so far as it really starts taking shape piece by piece. its much more wallet friendly than a $20 000 prostock for sure!

#15 Rick Brumback OFFLINE  

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Posted December 17, 2011 - 06:20 PM

as a guess i would say around 600,650 pounds,in that area.just a guess is all. you do know,that 800 pound class includes You as well as the tractor.




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