confused about 7 bolt rod swap

[1fast97gsx]

When I bought my eagle rods they were originally 1g rods. The shop I bought them from had them machined for a 7 bolt for some reason ( no clue why they didn't just stock 7 bolt rods ) but they told me I can run them fine and just to run 1g standard sized rod bearings. I did this and everything was great .... does this mean I can just swap the rods into a 6 bolt block still as well since 1g rod bearings are still working with these rods? Seems like it should swap right in ... but then I always hear 7 bolt and 6 bolt internals are not interchangeable without machining?

 

[half-cocked]

To make 6 bolt rods work in a 7 bolt you have to narrow the big end. This would give you too much play in the rods in a 6 bolt.

 

[sweet97]

This sounds like a brain teaser, a play on words. If a 6 bolt rod needs a smaller big end to work on a 7-bolt how would it be loose on a 6-bolt crank which is what it sounds like? The rod supplier knew their stuff, I might ask them. Mark

 

[Cesar]

7 bolt rods are slimmer than 6 bolt rods on the big end. Meaning you would have too much play when checking the thrust.

 

[sweet97]

Thanks for that info. I was thinking big end diameter only. Mark

 

[1fast97gsx]

well with the machining done to the rod I was told to use 1g rod bearings with them in a 2G BLOCK .... that's what confuses me. If 1g rod bearings work on the big end of the rod then why wouldn't they work with a 1g crank/ block since that's what the bearings were made for anyways???

 

[Cesar]

Listen,

The big end for both rods are the same diameter. the only factor which will effect the bearing size is whether or not the crank was ground/cut. Since the rods were machined to work on a 7 bolt they can no longer be used on a 6 bolt. Unless you don't care about how your motor is put together.

well with the machining done to the rod I was told to use 1g rod bearings with them in a 2G BLOCK .... that's what confuses me. If 1g rod bearings work on the big end of the rod then why wouldn't they work with a 1g crank/ block since that's what the bearings were made for anyways???

I'm sorry, that's a little confusing.

 

[1fast97gsx]

ok I see now.