S rods on A crank

[Vegard]

I've just had an A crank reground to fit S-rods. However, as we all know, S rods are too wide to fit the bearing journal.

I've measured that I need to remove approx 0.35mm from each side.

The question is: Should I remove the same amount from each side??

[eightport]

Yes, cut the same amount from both sides.You should try to keep the offset the same.

[littler]

keep the crank strong and make the rods light

[Vegard]

I calculated that I needed to remove 0.40mm from each side. Now done. Let's see if it fits the crank now

I know some engine builders in the UK uses LOTS of sideways thrust clearance on rods. Is there a clearance one should aim for?

[Vegard]

After removing the said amount, it was time to try the entire thing in the block. The pistons popped out 2,25mm. It was obvious that the block had been skimmed, so OK I though.
After measuring the rods I've found that I've just modified a set of 970 rods to fit a 1293 A crank.

Bollox!

I guess I have to fit these in a long stroke engine to get a better stroke/rod ratio.

Do you guys know if MED for instance widen the journals or narrow the rods in their long stroke engines?

Oh BTW. Those of you who think that 1071 and 970 rods are from the same forging with a differently drilled small end, you're wrong. The 970 rod is definitely from a "longer" forging.

[sandman]

Veggy;

"Everyone" knows that 1071 and 1275 share the same rods - unlike the 970, that uses longer rods...


(Sry - just could'nt resist adding some salt

[Vegard]

Ed you misunderstood. Some say that the 970 and 1071 are from the same forging, only drilled differently. This is surely not true.

[guru_1071]

whats that saying verg?

'measure twice, cut once......

[Vegard]

I never even knew I had a set of 970 rods. I think someone on Ebay has fooled me

[guru_1071]

I never even knew I had a set of 970 rods. I think someone on Ebay has fooled me

they are more likley long stroke 1275 rods.........

[Minimania]

Your opinions are welcome;

http://www.minimania.com/web/DisplayID/ ... ticleV.cfm

[Vegard]

Your opinions are welcome;

http://www.minimania.com/web/DisplayID/ ... ticleV.cfm

Long rods are god on an Asmathic engine, no doubt, so get us some longer rods and shorter pistons

Mmmmmmmmmmmmmm http://www.7ent.com/detail.cfm?pageid=2964

[Vegard]

It's not like I had few to choose from....

All S rods:


Three sets of modified A ones in addition waiting for balancing.



For those of you who have tried balancing rods, knows that it's one of the most shitty jobs ever... Luckily I didn't have so many to do...

[Vegard]

Damn Rich, you're disappointing me. How could you not be commenting on my rod?