Heymow.com

Mower Building / Setup Help => Drag Mowers => Topic started by: motleyfreak101 on June 01, 2009, 08:01:01 PM

Title: Drag tranny?
Post by: motleyfreak101 on June 01, 2009, 08:01:01 PM
First off, sorry for my ignorance to this, i am very new as to the trans and setpully set ups.  :confused: all i know is that i want to run a "?live axle set up?"  :confused: (if that right). i know what to do with the axle and sproket sizes, BUT, i have no clue what i should run for a tranny. what would be the most recomended transmission to put in my mower.

ANY advice would be greatly appreciated.
Thank you
Dereck

P.S. I am not running under any certain rules or regulations.
Title: Re: Drag tranny?
Post by: Kaptain Krunch on June 01, 2009, 08:02:10 PM
If your running a live axle, a peerless 700 series is the way to go.
Title: Re: Drag tranny?
Post by: motleyfreak101 on June 01, 2009, 08:08:06 PM
ok thank you.
A couple more questions. i have a 14 horse briggs opposed twin. bone stock just no govoner. what should i run for pully sizes. and i was looking at the 700 series and what is the differences between all of the different series? such as 700-012 or 700-023
Title: Re: Drag tranny?
Post by: Kaptain Krunch on June 01, 2009, 08:11:50 PM
Main difference would be # of gears/gear ratios. I'm not sure for the pulley sizes, depends on the ratio of tranny, ratio of chain and sprockets, and max ratio your class can run. Make sure you make a pretty beefy scatter shield for that flywheel.
Title: Re: Drag tranny?
Post by: motleyfreak101 on June 01, 2009, 08:26:35 PM
ya... ive been worried bout that fly wheel  :worried:.
But there really isnt a class requirement.
So say i run a 700-023 trans.
right now im runnin 6 1/2'' on engine i think like 5 1/2'' on rear.
this week im putting 9'' on engine, 4'' on rear.

and just out of curiousity what are the chances of the fly wheel blowing up on me
Title: Re: Drag tranny?
Post by: Kaptain Krunch on June 01, 2009, 08:35:33 PM
It really depends on what the ratio of the 700 your getting is, the one i got is 6:1 in 5th, but for drag you probably want to use 3rd gear, so i have no idea, you'll just have to wait and see.

As for the flywheel exploding, assuming you haven't modified it at all then chances are probably slim, but why risk it? If i were running ungoverned i'd go with atleast a 1/2 thick scatter shield, not sure where but somewhere around here there was a thread about a modded flywheel exploding, the scatter shield did nothing and it went right into the guys leg.
Title: Re: Drag tranny?
Post by: motleyfreak101 on June 01, 2009, 08:46:02 PM
once again thank you very much and i just have one more (stupid) question. with theese trannys do u need to shift through each gear. like a car for example?
 
Also where is the best place to buy these?

and also i dont know if it helps you at all but i am running the 1/8 mile strip.
Title: Re: Drag tranny?
Post by: Kaptain Krunch on June 01, 2009, 08:50:10 PM
Well i know most racers dont shift, and just leave it in one gear (most likely 3 or 4th depending on tranny). These use shift keys, and shifting while moving puts extra stress on everything. To get one i'd go to a junkyard, probably get your best deal there, just look for a rear engine rider like a small toro, or JD, my rear engine JD's and my rear engine toro use 700's.
Title: Re: Drag tranny?
Post by: motleyfreak101 on June 01, 2009, 09:12:46 PM
ok thank you so much.
you have been a great help.

but LOL i do have one more question.

the old rear engine mowers, to those run axles with the sprocket hub that i would be able to use?.
Title: Re: Drag tranny?
Post by: stubbysteve on June 02, 2009, 07:27:09 AM
hey not to butt in here but just to let you know, the drag racers around here have broke every 700 they have used cause the input housing of the tranny cant take all the beating that shifting gears puts on it. The best thing that is holding up at the moment is a peerless 5 sp tranny. But the most desirable is a centrifigal clutch with a right angled gear box to a live axel......less stress.
Title: Re: Drag tranny?
Post by: Wheelhorseracer on June 02, 2009, 09:19:03 AM
I agree.. the peerless 90 box I have seems to have nice LARGE gears.. The keep it from breaking off the ears (since i did that once) I would completely box in the 90 box since you will be leaving from a standing start with grip. The 90 box I have is from a Massey Ferguson mower deck.. look it up on ebay under mower parts and accessories.

You will need to gear it to jump out of the hole and rpm it out the back.. so for 150 foot I would be putting in a 8.50 or 9.00 gear with a 16 inch tire... you will need to leave hard like a Stock Eliminator Drag Car..

But for that I would say run a billet flywheel because of the revs you will make.

Title: Re: Drag tranny?
Post by: stubbysteve on June 02, 2009, 09:35:35 AM
ya here the engine has to of lawn mower origin but the rest of the drive chain is open. There is a guy here using a 350 yamaha warrior lower unit as a tranny and has been clocked at over 90 mph. The 160 ft straights they are doing in under 4.5 seconds.
Title: Re: Drag tranny?
Post by: Wheelhorseracer on June 02, 2009, 09:37:23 AM
WOW!!!!!!
Title: Re: Drag tranny?
Post by: stubbysteve on June 02, 2009, 09:52:55 AM
ya using a 20 hp honda ohv....stock..... seriously though they do.
here is that mower on this side.

http://www4.webng.com/MWDTA/PhotosL/OutL2.jpg
here you can see all the old photos here..........

http://www4.webng.com/MWDTA/photos.htm

you can go down in each catagory and see other pics,.....
Title: Re: Drag tranny?
Post by: motleyfreak101 on June 02, 2009, 01:05:14 PM
never had luck with ohv engines. always valve train went bad  :mad:
I would completely box in the 90 box since you will be leaving from a standing start with grip.
Sorry but what exactly do u mean by boxing it in?  :confused:
Title: Re: Drag tranny?
Post by: Wheelhorseracer on June 02, 2009, 01:59:44 PM
This is how I boxed in my 90 box to keep it from moving.. before this when the centrifugal clutch would engage it would shake the 90 box.. so i did this to keep it from braking off the ears..

(http://img.photobucket.com/albums/v302/GoldsackFamily/2008WOORacing/th_DSCF0054-1.jpg) (http://smg.photobucket.com/albums/v302/GoldsackFamily/2008WOORacing/?action=view&current=DSCF0054-1.jpg)
Title: Re: Drag tranny?
Post by: motleyfreak101 on June 02, 2009, 04:58:16 PM
o ok thank you i will keep that in mind.

sorry guys. i have a really dumb question... is a 40:1 ratio good or bad?  :confused: sorry i have no clue bout theese things
Title: Re: Drag tranny?
Post by: Kaptain Krunch on June 02, 2009, 05:24:28 PM
Bad, that means your engine has to spin 40 times for you tires to turn 1 time.
Title: Re: Drag tranny?
Post by: motleyfreak101 on June 02, 2009, 05:56:24 PM
oo ok i get the ratios now! thanks  :woo: