Cast Iron Pistons

[diesel9475]

I am trying to locate a set of Cast Iron Pistons for My 1937 John Deere A. I need to bore the block out due to some pitting and normal wear. I use the tractor for pulling now and stroking it. I want to keep cast pistons in it for the low end lugging power. Does Anybody know if i can locate cast iron pistons that are larger the just .045 over. Does anybody know of a manufacturer that makes them .125 over. All I am finding is aluminum.

 

[Anonymous-0]

why do you think cast iron pistons will help the lug of the tractor? When a john deere A is running at 1000 rpm the pistons come to a complete stop 2000 times a minute and then rverse direction. A heavier piston will only consume power as power is needed to resume movement of piston.Paul

 

[Drew]

Cast iron pistons will not help lugging power! You need aluminum pistons.

 

[Mike N Mo]

I don't think you'll find any cast iron pistons larger than .045" over. I agree with Skip (post below) that a heavier piston will NOT help on power. If I read your post correctly, you're stroking the crank??? If so, you want a shorter piston than a stock one anyway, assuming you're stroking it enough to make it worthwhile (9"+). My $0.02 worth. Mike

 

[diesel9475]

When I pulled against guys with stroked cranks and aluminum pistons my tractor with late model crank and cast pistons my tractor had more lugging power when loaded then the tractors with aluminum pistons. Im not into the highly modified pulling.. I do transfer and stone boat pulls. But my tractor with cast pistons when on a load can lug way down and keep pulling when the tractors with aluminum pistons cant.

 

[toot]

something must have not been completely set up right or tuned.. my alum piston tractors are much more perkier and stronger on the track than my slug iron piston tractors, plus the aluminum has higher compression to offer. You said you are stroking it, I know no one that has cast pistons with strokers. Stoking gives you the low end lugging power, not piston material.

 

[wilamayb]

Heavier rotating mass is a parasitic loss not a gain in any form.

Why would you not want high compression aluminum pistions? They are lighter, make more power, and are easier to obtain.

 

[LarrySTN]

If cast iron pistons made more power, that would mean they have better thermal dynamics therefore more effiecent, if more effiecent then all engine manufactureres today would be using cast iron pistons to help them meet federal fuel economy standard. They use ALUMINUM pistons, they are much lighter and therefore much less parasitic power loss. If your tractor had more lugging power, it was NOT due to cast iron pistons.

 

[Anonymous-0]

some people you just can't help!!!!! but skip and the rest of them are absolutely correct!!!!

 

[buickanddeere]

Same tractor on the dyno with the exception of cast then rebuilt with aluminum pistons.
There will be zero difference in power except maybe a tiny wee bit more with the aluminum pistons. Due to less reciprocating part friction.

The school system needs to be examined. There are people graduating yet they don't understand basic physics.

 

[Mike M]

Well I guess I'm about the only one that agrees with you.
I can tell the differance in a late model A with cast iron pistons verses a similar compression aluminum ones. Alum revs up quicker and also dies off quicker.

And what ever happened to the theroy of motion that objects in motion say in motion and a heavier object stays in motion longer as it will take longer to slow it down.

Now if you are running all-fuel pistons and want to tractor pull higher compression gas pistons will boost your HP which can only help.

 

[mike321]

I put aluminum pistons in my 60 and gained 5 hp

 

[jd b puller]

diesel, listen to the folks on here. (Except for the ones that think thier heavy flywheel helps in transfer pulling). Lighter pistons are good. Heavy pistons are bad.

This notion of wanting "lugging" seems weird too. As an example...

I have fairly large aluminum pistons, a decent stroke, and 11:1 compression. Everyone asks me if it lugs well with all that compression.

Honestly, I don't know, I've never lugged it. I generally pull in 4th and 5th gear up to 4500# class and don't generally drop more than a few hundred RPM's. Lugging means you're on you're last leg.

If we could take your tractor and mark where it starts "lugging" and where it stops (dies), then jump in our time machine and rebuild the motor to have double or triple the HP you have now, you wouldn't lug it at all. Make sense?

 

[diesel9475]

Well I guess I started a really interesting topic. But from all my expirences when I pulled against an aluminum piston tractor I had alot more torque then them. But thank you every one for your input. And some auto manufactures are going back cast iron pistons. Thanks everyone for their input.

 

[wilamayb]

No doubt the aluminum pistons didnt hurt HP but the real difference came in that most if not all new aluminum pistons are MW style which means they are higher compression than factory gas pistons.

Also did you install new valves? Mill the head and block? These changes will also make minute differences.

 

[wilamayb]

All I can say is to put it on a dyno. You'll find it's only in your head. Torque is a function of HP. If torque really is increasing with cast iron pistons so will HP. It aint gonna happen.

 

[gtx1967jewison]

yep. heres your answer. the piston starts & stops TWO times every crankshaft revolution. would you guess its easier/less wasted power to start/stop a heavy object or a light object? do heavy cars accelerate & stop easier than lighter ones? I really am just speechless that this is even a debate. put it on a dyno & SEE the hp loss with the heavy slugs. the lighter they are the more power is left over to turn the wheels. duh.

 

[jd b puller]

have seen some diesels going back to cast iron. Not because they want to, but because they have to run them so danged hot to try to meet emissions.

 

[Drew]

At the Performance Racing Industry show last December, the Mahle/Clevite booth had a steel diesel piston on display. I would have to say it was about the oddest looking piston I have ever seen. The reason they gave for using steel as the material was in a HPCR engine the fuel comes out of the injector at such a high pressure that it was erroding the edge of the bowl away at the top of an aluminum piston. They cut/left material out everywhere they could to reduce weight.

 

[mike321]

It had 41 hp before I tore it apart. No they are not m&w pistons. I did redo the head.

 

[wilamayb]

Notice my post calls them "MW style" which is exactly what you got. Unless you got them from a special source the MW style is the norm for replacement.

If you had put the old pistons up beside the new you would have seen a difference.

 

[Handsome Jim]

1-800

 

[Handsome Jim]

1-800

 

[Handsome Jim]

1-800

 

[buickanddeere]

(quoted from post at 19:47:16 02/11/10) yep. heres your answer. the piston starts & stops TWO times every crankshaft revolution. would you guess its easier/less wasted power to start/stop a heavy object or a light object? do heavy cars accelerate & stop easier than lighter ones? I really am just speechless that this is even a debate. put it on a dyno & SEE the hp loss with the heavy slugs. the lighter they are the more power is left over to turn the wheels. duh.

The pistons are not decelerating against a friction brake. The energy from the decelerating piston nearing the end of it's stroke.Is used to accelerate another piston starting it's stroke.