On 10/31/2004 I did big-end journal sizes of one rod, to get some practice in on using my caliper (analog, thimble-type). I concluded that it was 2.244, which is about 4 thou above high-limit for a std rod.
On 7/3/2005 I measured by weight the rods and the new JE pistons I got. The rods have numbers on the outside of their caps (so you don't mix/match them--why two of mine have the same number(!!) is beyond me.
| 700 | -479g |
| 742 | -480.5g |
| 204 | -481g |
| 204 | -480.5g |
Because there are two 204s, but their weights are different, I'm referring to one as "204(h)" (for "heavy"). It is a pig, well, really, the 700 is 1.5g too light and shouldn't be in this set, but what are you going to do?
The pistons are a little close than the rods, only 0.5g off, rather than a full gram (unacceptable).
| Piston | pis. +ring | wristpin | ||||||||||||||
| 1 | 410.5 | 95 | ||||||||||||||
| 2 | 410.5 | 95 | ||||||||||||||
| 3 | 410.5 | 95 | ||||||||||||||
| 4 | 411.0 | 95 |
I have to do some dressing to get this gang of parts within spec. If I start by matching the 411.0 piston with the #700 rod, I can reduce that big diff between the 204(h) and the light 700 rod. I was hoping I would only have to dress two rods, to be a 1/2 gram out on the high on each throw. But the rods were two grams different high to low, and the 0.5g of the pistons doesn't cover that gap. If I took the heavy #204(h) rod down to 480.0, that would bring its total to 890.5 and within a 1/2 g of the two "middles. But that leaves the "low" pair still a gram out. Does that 1.0g put too much whip on the crank? Which journal should the low pair of rod #700 go on if there is a difference?
| Mix and match table | |||
| Rod No. | Rod wght | Cyl. Wght. | Total |
| 204(h) | 481.0 | 410.5 | 891.5 |
| 742 | 480.5 | 410.5 | 891.0 |
| 204 | 480.5 | 410.5 | 891.0 |
| 700 | 479.0 | 411.0 | 890.0 |
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