300 and 240 Rod length?
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300 and 240 Rod length?
How long are the 300 Rods? How long are the '65-'67 240 rods?
I am trying to calculate the numbers in changing over to a 300 crank and the early 240 rods in an effort to determine the rod/stroke ratio. Stroke is: 300, 3.98" and 240, 3.18" -- of course, I just need the exact measurements of the rods. Somebody got a motor book?
Specifically what I am planning:
Brush the P.D. on the 24 rods from .912" to .9272"
Use 1.160" Ford 302 pistons designed for 400 rods (KB333)
I am trying to calculate the numbers in changing over to a 300 crank and the early 240 rods in an effort to determine the rod/stroke ratio. Stroke is: 300, 3.98" and 240, 3.18" -- of course, I just need the exact measurements of the rods. Somebody got a motor book?
Specifically what I am planning:
Brush the P.D. on the 24 rods from .912" to .9272"
Use 1.160" Ford 302 pistons designed for 400 rods (KB333)
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300 and 240 Rod length?
That's correct - I am sure the 240 rods are .400" longer. But I need the exact dimensions of the rods to be sure that I will be able to obtain the correct compression height (1.160") from aftermarket or custom pistons. Also I want the measurements of the 300 rods in order to compute the relative rod/stroke ratios.
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300 and 240 Rod length?
rtbstrd,
I finally found a copy of the old 'Dave Williams Rod Ratio List'.
It used to be at 'http://members.xoom.com/ronin42/index.htm'. Anybody know where it resides now? Here's a 240-300 clip from it:
For some reason I get asked about rod ratios a lot. Must be all those stroker motors I build. [grin] Anyway, I made up a small chart so you could see how common OEM engines and common stroker combinations stack up to each other. Note some very common engines regarded as long lived or high RPM turn out to have relatively poor rod ratios, while some of the better ratio engines have reps as low RPM, low performance luggers. Which mainly shows rod ratio isn't everything, so don't get your knickers all in a twist about it.
source: dave.williams@chaos.lrk.ar.us
engine-------stroke---rod-----ratio---note
Ford 240 Six 3.18 6.79 2.13
Ford 300 Six 4 6.21 1.55
Hope this helps,
Brett
I finally found a copy of the old 'Dave Williams Rod Ratio List'.
It used to be at 'http://members.xoom.com/ronin42/index.htm'. Anybody know where it resides now? Here's a 240-300 clip from it:
For some reason I get asked about rod ratios a lot. Must be all those stroker motors I build. [grin] Anyway, I made up a small chart so you could see how common OEM engines and common stroker combinations stack up to each other. Note some very common engines regarded as long lived or high RPM turn out to have relatively poor rod ratios, while some of the better ratio engines have reps as low RPM, low performance luggers. Which mainly shows rod ratio isn't everything, so don't get your knickers all in a twist about it.
source: dave.williams@chaos.lrk.ar.us
engine-------stroke---rod-----ratio---note
Ford 240 Six 3.18 6.79 2.13
Ford 300 Six 4 6.21 1.55
Hope this helps,
Brett
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300 and 240 Rod length?
Brett, THANKS! Been looking for this info for a long time. And surveying opinions about rod/stroke ratios. Pretty widely debated... The general consensus, as you stated, seems to be that as long as you are changing a tenth here and a tenth there in the middle of, say 1.5 - 2, the rod ratio doesn't really make a material difference in a street motor.
I will be using '66 240 rods with a 300 crank, so my r/s ratio will come to 1.71. Very acceptable.
Now all I have to do is find the right compression height piston. Hopefully off the shelf. KB makes a 383 Che*y stroker piston with a CH of 1.130" and a 351W stroker piston at 1.160" - I think either of these will work, but I need to remeasure and recalculate. Thanks again for the info!
I will be using '66 240 rods with a 300 crank, so my r/s ratio will come to 1.71. Very acceptable.
Now all I have to do is find the right compression height piston. Hopefully off the shelf. KB makes a 383 Che*y stroker piston with a CH of 1.130" and a 351W stroker piston at 1.160" - I think either of these will work, but I need to remeasure and recalculate. Thanks again for the info!
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