Pistons

[Stoegs]

By using WD flat top pistons in a D17 what will be the compression ratio be? Will there be any complications.
Thanks Bill

 

[Nordic]

Hi Bill, someone might come along that knows the ratio, however, if you have the engine apart as well as a flat top piston and I assume the head is also flat, you can probably take all the measurements and do the calculation manually. It would be kind of fun to do.

 

[Stoegs]

Hi Bill, someone might come along that knows the ratio, however, if you have the engine apart as well as a flat top piston and I assume the head is also flat, you can probably take all the measurements and do the calculation manually. It would be kind of fun to do.

Nothing apart yet, just making a game plan.

 

[4wdtom]

By using WD flat top pistons in a D17 what will be the compression ratio be? Will there be any complications.
Thanks Bill

Flat top WD pistons are for the 4" stroke WD engine. When they added 1/2" stroke for the 45 and D 17 and went to power crater piston tops the piston pin location was changed to compensate so the compression wouldn't be way too much. The piston comes up 1/4" higher in the 45 and D 17 engine, I don't know how much that would raise the compression but it would be a lot I think.

 

[Stoegs]

Flat top WD pistons are for the 4" stroke WD engine. When they added 1/2" stroke for the 45 and D 17 and went to power crater piston tops the piston pin location was changed to compensate so the compression wouldn't be way too much. The piston comes up 1/4" higher in the 45 and D 17 engine, I don't know how much that would raise the compression but it would be a lot I think.

Thanks

 

[VicS]

Its not to much. But need to use premium gas at least.

 

[Tramway Guy]

There were several different pistons used in the WD. One used for distillate with around 4.5 compression might be OK in the WD-45 and give compression near normal.

 

[4wdtom]

There were several different pistons used in the WD. One used for distillate with around 4.5 compression might be OK in the WD-45 and give compression near normal.

Good point, but why not use the power crater pistons it should have? 45s have plenty of power stock and part of the reason for this is the design of the piston top which creates turbulence for better combustion.