Fletch
Member
These are both slant heads. The first is Grubee Skyhawk and the second is an engine from Zoom (not sure the model).
I'd like to know if the zoom head is OK with those "imperfections" or if it will crack down the road?
My second question (still being a novice to engines) is which head is better designed (better performance)? IOW...which one would you rather use?
I had them side by side and I'll let the pics speak for themselves, but I will add a few things:
The markings that look like cracks in the zoom head you can't feel with the exception of the largest one, and it is very minimal (I sanded and polished).
The skyhawk head seems more pronouncedly circular shaped (both combustion area and spark plug indent), and even appears to me to be somewhat smaller in diameter?
Lastly because you cannot see this... The part that mates with the cylinder... the square "lip", is much shallower on the zoom head (about 1.25mm) when compared to the Grubee (about 2.75mm). I'm sure this allows for more compression as it is like shaving the head or using a really thin gasket. The grubee is warped though and the zoom is nice and flat.
Any opinions on which I should use or comments are greatly welcomed. I'm still learning, and I may try both heads and see which gets better performance too.
Also FWIW, the zoom head has taller cooling fins.
Thanks
I'd like to know if the zoom head is OK with those "imperfections" or if it will crack down the road?
My second question (still being a novice to engines) is which head is better designed (better performance)? IOW...which one would you rather use?
I had them side by side and I'll let the pics speak for themselves, but I will add a few things:
The markings that look like cracks in the zoom head you can't feel with the exception of the largest one, and it is very minimal (I sanded and polished).
The skyhawk head seems more pronouncedly circular shaped (both combustion area and spark plug indent), and even appears to me to be somewhat smaller in diameter?
Lastly because you cannot see this... The part that mates with the cylinder... the square "lip", is much shallower on the zoom head (about 1.25mm) when compared to the Grubee (about 2.75mm). I'm sure this allows for more compression as it is like shaving the head or using a really thin gasket. The grubee is warped though and the zoom is nice and flat.
Any opinions on which I should use or comments are greatly welcomed. I'm still learning, and I may try both heads and see which gets better performance too.
Also FWIW, the zoom head has taller cooling fins.
Thanks
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