Author Topic: Re-use rods  (Read 11906 times)

0 Members and 1 Guest are viewing this topic.

Offline more4les

  • Mow-Forum Junkie
  • ***
  • Posts: 1212
  • Karma: 15
  • Gender: Male
  • FatBoyZ Racing - Mowin' Down the Competition!
    • View Profile
    • Northern  NY Lawn Mower Racing
Re: Re-use rods
« Reply #30 on: November 30, 2012, 04:42:51 PM »
Sorry, mill the piston. I don't have any pictures though. Don't modify the head unless you need to clearance the valves (big cam).

Lester
2012 & 2014 Sportsman Champion (Builder/Owner), 2013 2nd.
2011 - 2014 Pro-Mod Champion, 2011, 2014 2nd Builder/Owner
2008-2013 Pro-Stock Champion (2009-13 Builder/Owner)
2007 Pro-Mod Champion
Founder of NNYLMR
http://sports.groups.yahoo.com/group/NNYLMR/
Front Yard Chassis
Impact Racing Engines
http://www.facebook.com/groups/NNYLMR/
SKYPE ME: more4les

Offline BIG AL 202

  • Highly Mowtivated
  • ****
  • Posts: 3219
  • Karma: 8
  • Gender: Male
  • LET'S GO FIND A NEW PLACE TO RACE MOWERS!
    • View Profile
Re: Re-use rods
« Reply #31 on: November 30, 2012, 05:03:59 PM »
You put the piston on the rod then, with no rings, put it in the cylinder. Bolt it to the crank and roll it over, then check how far it sticks out of the cylinder. Mill off that much, you have to check both and mark them for their respective cylinder.
ALWAYS VOTE FOR ED!   FONGS BROTHER FROM ANOTHER MOTHER!

Offline NH Mowster

  • Turf Warrior
  • **
  • Posts: 214
  • Karma: 0
  • Gender: Male
  • Wabash Valley Mower Racers
    • View Profile
Re: Re-use rods
« Reply #32 on: November 30, 2012, 05:30:06 PM »
Oh OK I get it. That's what I thought you meant just wanted to make sure. Do I use the 40 cam or the 42 cam?
Holland S8 Oppy powered ModX
FXT


Offline BIG AL 202

  • Highly Mowtivated
  • ****
  • Posts: 3219
  • Karma: 8
  • Gender: Male
  • LET'S GO FIND A NEW PLACE TO RACE MOWERS!
    • View Profile
Re: Re-use rods
« Reply #33 on: December 01, 2012, 07:02:56 AM »
They should be the same but measure the lift and use the one with the most.
ALWAYS VOTE FOR ED!   FONGS BROTHER FROM ANOTHER MOTHER!

Offline NH Mowster

  • Turf Warrior
  • **
  • Posts: 214
  • Karma: 0
  • Gender: Male
  • Wabash Valley Mower Racers
    • View Profile
Re: Re-use rods
« Reply #34 on: December 01, 2012, 03:44:17 PM »
I got the 40 cid engine tore apart and got the 42 crank placed in with the 40 rods. It looks like I will have to take about .065-.070 off the top of the pistons. Of course I'm not going to do it till I get the rods resized and get a little further into the build. I posted a picture and hopefully it will post. I'm waiting for Don's video to come in the mail before I do anything else. The 42 cid cam is the same size as the 40 cid cam so I'm going to run the 42 cam.
Holland S8 Oppy powered ModX
FXT

Offline NH Mowster

  • Turf Warrior
  • **
  • Posts: 214
  • Karma: 0
  • Gender: Male
  • Wabash Valley Mower Racers
    • View Profile
Re: Re-use rods
« Reply #35 on: December 04, 2012, 05:51:23 AM »
I have 2 different types of 42 heads.one has a .020 ledge where the head gasket sits and the other one is completely flat. When I mill the piston I'm thinking of putting it on the lathe and making it a slight dome and use the thicker ledge head. I checked and from the deck to the spot right above the piston is about .050 distance and its only .030 with the completely flat head. Does anybody think that having say .020-.030 dome improve anything besides compression?
Holland S8 Oppy powered ModX
FXT

Offline birdman_express

  • I'm not fast...but man I can eat! INTEKS RULE THE PITS!!
  • Global Moderator
  • Highly Mowtivated
  • *****
  • Posts: 3963
  • Karma: 31
  • Gender: Male
    • View Profile
Re: Re-use rods
« Reply #36 on: December 04, 2012, 09:22:37 AM »
I have 2 different types of 42 heads.one has a .020 ledge where the head gasket sits and the other one is completely flat. When I mill the piston I'm thinking of putting it on the lathe and making it a slight dome and use the thicker ledge head. I checked and from the deck to the spot right above the piston is about .050 distance and its only .030 with the completely flat head. Does anybody think that having say .020-.030 dome improve anything besides compression?

I am not the flathead guy, but ALL I do hear from the ones who are purveyors of the Flatness, say flow..... Flow.....

FLOW!!!!!
Marc Baker

ARC Dealer

Marc from ARC.... "Billet Billet"

Powered by a Full Bug E.C. 20HP Vanguard!!!!


Offline Jim Knutson

  • Mow-Forum Junkie
  • ***
  • Posts: 1340
  • Karma: 11
  • Gender: Male
  • i didnt break it......i modified it!
    • View Profile
Re: Re-use rods
« Reply #37 on: December 04, 2012, 09:29:00 AM »
use the heads with the ledge....but if you cam it, check for valve clearance in the pocket area. :woo:
If you quit when you're behind, you will never win.

Offline NH Mowster

  • Turf Warrior
  • **
  • Posts: 214
  • Karma: 0
  • Gender: Male
  • Wabash Valley Mower Racers
    • View Profile
Re: Re-use rods
« Reply #38 on: December 04, 2012, 10:35:58 AM »
I understand about flow and that's why I asked if anybody has tried to dome the piston. Would that help or hurt flow?
Holland S8 Oppy powered ModX
FXT

Offline The Tank

  • Highly Mowtivated
  • ****
  • Posts: 3542
  • Karma: 10
  • Gender: Male
  • #44 Tank Racing!!!
    • View Profile
Re: Re-use rods
« Reply #39 on: December 04, 2012, 10:50:19 AM »
I understand about flow and that's why I asked if anybody has tried to dome the piston. Would that help or hurt flow?
A dome piston is used to raise the compression. I'm no fathead guy either but I think the dome piston would hurt the flow.
Frank "The Tank" Woods

AKA "The Intek Outlaw"

Offline Jim Knutson

  • Mow-Forum Junkie
  • ***
  • Posts: 1340
  • Karma: 11
  • Gender: Male
  • i didnt break it......i modified it!
    • View Profile
Re: Re-use rods
« Reply #40 on: December 04, 2012, 11:01:24 AM »
i ran .020 pop-out with a flat piston, and the taller head. besides making it harder to start, it returned negligible returns. i dont think running a dome, or pop-out is worth the time, or money in machine work.
If you quit when you're behind, you will never win.

Offline NH Mowster

  • Turf Warrior
  • **
  • Posts: 214
  • Karma: 0
  • Gender: Male
  • Wabash Valley Mower Racers
    • View Profile
Re: Re-use rods
« Reply #41 on: December 04, 2012, 11:16:33 AM »
i ran .020 pop-out with a flat piston, and the taller head. besides making it harder to start, it returned negligible returns. i dont think running a dome, or pop-out is worth the time, or money in machine work.
OK that's jim. I didn't think it would help to much but I figured I would ask. I've been wrong before :doh:  Dons video should come in the mail today and I've got the crank polished. Going to recon the rods this weekend and start ordering some parts. Thanks everybody for your inputs, its greatly appreciated  :twothumbsup: if anybody thinks of anything that I may miss please post it.
Holland S8 Oppy powered ModX
FXT

Offline FlatheadPuller

  • Turf Warrior
  • **
  • Posts: 973
  • Karma: 12
  • Gender: Male
    • View Profile
Re: Re-use rods
« Reply #42 on: December 04, 2012, 02:14:05 PM »
In order to run pop out and have it be of a help you have to run big valves and big ports. Also the cylinder head must be machined to accept it. The port and seat area are not large enough in an oppy unless there has been some welding done do this. When the engine is all done pull the heads off and check the burn pattern. It will tell you alot. It will tell you if the engine is efficent or not. 2/3rds the piston should be black with carbon. Should be a half circle over the piston in carbon or staining. If it is not your combustion chamber is to tight and all that compression is killing it. Machine the piston flat with zero deck and run a 42 or 46 head. It will run good. If you want it to turn hard keep adding duration on the camshaft. They will clear .340-.360 lift with out machine work and still have the needed clearance around and over top the valve. Keep .100 clearance around and over top the valve when open. If you dont have it machine it untill you do. It will run. If the ead was thick enough yes you could run a stock piston and pop it out. leave it flat. Machine the head to accept it with .075-.100 clearance between the head and piston. Chamfer the leading edge of teh piston and rock and roll. But I wouldnt do this in a splasher luber system. The idea is to make it live and that requires removing rotating wieght from the rods. Thus longer rods and shorter lighter pistons.
The popout helps flow when utilized. The transfer area between the valves and the bore is bigger when poping the piston out. This helps flow but it must be done correctly.
Dennis Bazzett
Grandville Michigan

Offline NH Mowster

  • Turf Warrior
  • **
  • Posts: 214
  • Karma: 0
  • Gender: Male
  • Wabash Valley Mower Racers
    • View Profile
Re: Re-use rods
« Reply #43 on: December 04, 2012, 02:20:30 PM »
Thanks Flathead Puller.
Holland S8 Oppy powered ModX
FXT

Offline FlatheadPuller

  • Turf Warrior
  • **
  • Posts: 973
  • Karma: 12
  • Gender: Male
    • View Profile
Re: Re-use rods
« Reply #44 on: December 04, 2012, 02:23:14 PM »

Gienger cam and custom crank





Stock rods with bearing inserts in them. The bearings are for a 1.0 automotive engine. Resized to fit the bearing. Crank journal resized to fit the bearing. These were built before ARC had rods.
Dennis Bazzett
Grandville Michigan

 

anything