Author Topic: Are All Opposed Twin Blocks The Same?  (Read 593 times)

0 Members and 1 Guest are viewing this topic.

Offline laurw1

  • Newbie
  • *
  • Posts: 3
  • Karma: 0
    • View Profile
Are All Opposed Twin Blocks The Same?
« on: May 15, 2018, 08:17:17 AM »
Hey so I was wondering if say the blocks for the 40, 42, and 46CI blocks are all the same. I am asking because I have a 42CI 18HP opposed twin with a wrecked block, and a 40CI 16HP opposed twin thats all good, so I was wondering if I could swap the crank and rods from the 18HP and put them into the 16HP without having to mill the pistons?



Offline PJG56

  • Turf Warrior
  • **
  • Posts: 536
  • Karma: 4
  • Gender: Male
    • View Profile
Re: Are All Opposed Twin Blocks The Same?
« Reply #1 on: May 15, 2018, 09:44:36 AM »
40ci & 42ci blocks are basically the same so you can swap crank and rods,with no issues
Paul Guptill  (oppy) #238modX
2012 slmra mowstock champion(builder/owner)

2013 slmra mowdified champion(builder/owner)
2013 ARMA national champion Mod-X(builder/owner)
2014 ARMA national champion Mod-X(builder/owner)
2014 All American Champion Mod-X/CP(builder/owner)
2014All American Champion FXT (engine builder)
2014 All American 2nd place SP(builder/owner)
2015 All American 2nd place BP (builder/owner)
2016 OutlawTriple Crown FXT Champion (engine builder)

Offline laurw1

  • Newbie
  • *
  • Posts: 3
  • Karma: 0
    • View Profile
Re: Are All Opposed Twin Blocks The Same?
« Reply #2 on: May 15, 2018, 10:53:50 AM »
Thank you, do you know the differences the 46CI block has? I'm curious now


Offline PJG56

  • Turf Warrior
  • **
  • Posts: 536
  • Karma: 4
  • Gender: Male
    • View Profile
Re: Are All Opposed Twin Blocks The Same?
« Reply #3 on: May 15, 2018, 02:18:27 PM »
On the long stroke 46 there are cutouts in the block for the rods to clear,thats the only difference.
on the short stroke 46 the block is the same as the 42 and uses its crank,but has a 3.5625 bore instead of the standard bore of the 40,42& 46 of 3.4375

the 40ci has 2.19 stroke,42 has 2.28 stroke and long stroke 46 has 2.46 stroke
big bore short stroke is 2.28 same as 42ci
Paul Guptill  (oppy) #238modX
2012 slmra mowstock champion(builder/owner)

2013 slmra mowdified champion(builder/owner)
2013 ARMA national champion Mod-X(builder/owner)
2014 ARMA national champion Mod-X(builder/owner)
2014 All American Champion Mod-X/CP(builder/owner)
2014All American Champion FXT (engine builder)
2014 All American 2nd place SP(builder/owner)
2015 All American 2nd place BP (builder/owner)
2016 OutlawTriple Crown FXT Champion (engine builder)

Offline BIG AL 202

  • Highly Mowtivated
  • ****
  • Posts: 3223
  • Karma: 8
  • Gender: Male
  • LET'S GO FIND A NEW PLACE TO RACE MOWERS!
    • View Profile
Re: Are All Opposed Twin Blocks The Same?
« Reply #4 on: May 16, 2018, 11:33:14 AM »
They also had pressure lube blocks and they did make a big bore block. The big bore block used a 42ci crank to keep it 46ci. The horizontal and vertical blocks are different but alot of the internals interchange. I have heard of big and small valve blocks but have not seen any.
ALWAYS VOTE FOR ED!   FONGS BROTHER FROM ANOTHER MOTHER!

Offline rotten ron

  • Turf Warrior
  • **
  • Posts: 610
  • Karma: 10
  • Gender: Male
    • View Profile
Re: Are All Opposed Twin Blocks The Same?
« Reply #5 on: May 16, 2018, 09:38:00 PM »
Where is Rooster? He knows all about these blocks

Offline cycloneracer

  • Easy Parcheesy!!!!!!!
  • Global Moderator
  • Highly Mowtivated
  • *****
  • Posts: 4116
  • Karma: 37
  • Gender: Male
  • Easy Parcheesy!!!!!!!
    • View Profile
Re: Are All Opposed Twin Blocks The Same?
« Reply #6 on: May 17, 2018, 11:13:43 AM »
Rooster hasnít been here since 2014........
Paul Krueger

****2017 USLMRA FXT points Champion****

#150 Worlds First "sidewinder" FX (now dismantled)

#150 FXT  Sponsored by Zach Kerber Machine. http://zkbrmachine.com/

Easy Parcheesy Racing


 

anything