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All other non-specific model Farmall / IH / CASE tractors. (Catch-All)

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Dome or Flat head pistons

Tue Oct 13, 2009 12:09 pm

I am getting ready to finish the M Project. However I am not sure which pistons to get.
It is a distillate but am not intending on burning K1. it has a 45 head on it and seems to have the proper clearances for domes.
What are the advantage/disadvantage . of either/ or.
I need to help deciding today.
Phil

Re: Dome or Flat head pistons

Tue Oct 13, 2009 12:44 pm

The dome pistons result in higher compression, thus giving more horsepower, and were original equipment on tractors with the "X1" serial number suffix, which designates "high compression, gasoline". If you will be "working" the M, go with the step head pistons. If it will be mostly a parade and show tractor, the choice of pistons really doesn't make any difference, although the lower compression, flat top pistons MIGHT result in easier starting, especially if the battery is a little weak.

Re: Dome or Flat head pistons

Tue Oct 13, 2009 4:33 pm

The whole idea of distilate was more power cheaper. That said do what you want.

Re: Dome or Flat head pistons

Tue Oct 13, 2009 8:34 pm

beaconlight wrote:The whole idea of distilate was more power cheaper. That said do what you want.
I know the idea was cheaper, and at the time that was definitely true by a large factor, but old timers I talked to that ran them said they could not tell any increase in power.

Re: Dome or Flat head pistons

Wed Oct 14, 2009 8:01 am

Distillate fuel was several cents cheaper than gasoline. That is why it was the main fuel of choice, but it did NOT yield more power, which is why IH offered the optional high compression, gasoline only version, which DID produce slightly more power.

Re: Dome or Flat head pistons

Wed Oct 14, 2009 8:13 am

I ordered the dome style They were 60 bucks cheaper than the flat head as a whole. with the thought tat i am not running k1 I figured it would not make much difference, should I run a higher octane or would reg unleaded be OK
Thanks for the input.
Phil

Re: Dome or Flat head pistons

Wed Oct 14, 2009 6:55 pm

The compression still won't be THAT high. Regular gas will be fine.

Re: Dome or Flat head pistons

Thu Oct 15, 2009 9:51 am

Yes, regular unleaded will be just fine. E-10 is what I use in all my tractors.
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