[NBF823]

I got a new set of rods(4); 770, 824, 820, and 828 in grams. Is this a problem? What's going on here? The sheet inside says 387 for all big end weights, and two at what looks like 173 and two at 175. Is this a problem?

I haven't weighed them myself yet, but I think this is what they weigh according to the sheet in the box. What should I do? These piglets came from the other side of the globe, and shipping wasn't cheap.

Is my machinist going to have a hissy? - I'm just about to have one.

[leeseracing]

I'm not an expert but here are the rod weights of the Eagle rods I recently put in my 455 build: http://www.leeseracing.com/wp/2011/10/rod-weights/ Seems like the numbers you are seeing vary substantially more than the ones I used. I paired heavy rods with lighter pistons and tried to put matching weights across from each other (on the same crank journal) - perhaps that same strategy could work with your set, depending on how much your pistons vary, I guess

[NBF823]

Well, if what I read in the box, one of these rods weighs less - in the middle. This is a 4-cyl. I'll try to check tomorrow, but I don't have a fixture.

I can check the overall very accurately, but I really don't like this. This turd is to go to 8500 rpm and one is 50gm lighter. Where the heck is the 50 GM on the others? That's like a 9th of a lb isn't it?

The 173/175 is the little end.

[racegto65]

28 grams in an ounce and 16 ounces in a pound. Now consider that at 8500 and you can see the out of balance will be a problem. Since most inline 4 cylinders have 2 throws "up" and "2" throws down they will counter balance each other during one cycle assuming they are somewhat close in weight. Ideally the rod small ends will all be the same,the big ends will all be the same and the piston assemblys(piston,rings,and bearing) will all be the same.
I would deffinatly have them rebalanced!

[NBF823]

I'll get to check tomorrow at work with a good Ohaus. I'm starting to think someone botched the weight stamping on this one rod. If not, I gotta em closer than that, pretty much with a new one i think. I just can't see where that much weight is absent in the rod, nor where It could be removed in the others. They're h beams, much like eagles - there's no weight balance pad, and even if there were; all the documents sort of point to the beam section of the rod.

50 grams is a major defect - I've never heard of anyone sending out a set like that before. I paid around $100 just to have them shipped to the us.

[rexs73gto]

Personnaly I would send them back & make them pay for the shipping both way to get you a set that is closer in total weight. With that much wieght off difference probley wouldn't be bad for an engine that your just driveing at normal speeds but you would still have to match weight all the componantes to get the total weight close. But for me I wouldn't take the chance of useing thoise rods. When I got my new rods for my 455 they were all with in 3 10th's of each other & I still had them sonic balanced to get them closer. When I got down with the piston/rod assy's they were all excatly the same at 510 grams total. If your going to build it take the time to build it right.

[NBF823]

I jumped the gun - they were all 625g via Ohaus..

I apologize - lack of sleep and a stressful schedule, combined with multiple markings on the pieces as well as the weigh sheet, as well as this build being a battle allowed plenty of opportunity for poor performance on my part. There is nothing wrong on the manufacturers part.

But there's no excuse - I need a gram scale in my house.

Thanks for your time, again I apologize.

[Rob B]

Glad everything checked out ok for ya!

[Cammer-6]

I bought one of those digital postal scales that goes to 1000 grams(2.2 Lb)
for weighing my pad stamping ink. I think it was less than $50.
buy a standard to check it too.