Kicked a rods again

Not silly if you don't know !!,there is a v and m series bearing that are basically a different hardness between the 2 bearings,as I understand it (but I may be wrong and please any1 feel free to correct me ) the m series is a harder compound bearing than the v series,I think the v series is the more favoured bearing when you start really leaning on the motors !!!

 

MGP Rods, (just bought a set)require straight 50 wt., They were very specific about that.

 

Clevite bearings are available in "M" series (soft) or "V" Series (hard)....most teams use the M bearings to measure the squish and then switch to the V bearings when their tune up is close....cylinders are balanced and the plugs & bearings look good and match...

We used the M bearings on the rods only....I'm not sure if the mains are available in M & V but I would not use M bearing on the mains....no reason the smash them trying to get the tune up correct...

 

We record 10 seconds of data and there is no drop off in oil pressure and we always have a few quarts of oil left in the oil tank when we get back to the pits, I might set the logger to record a bit longer in future at the moment we only have 10 sec pre and post launch.

 

On rod bolts - I don't think you are in need of any super duper bolts - arp is a good bolt - the 2000 is fine - they make a custom age 625 and they are nice but pricey - of course if you want to run 11,200 rpm shift points then thats a different story. On bearings the V is the softer bearing and will squish if you lean on it over the edge - and it still lives and keeps on going. The M bearing is a hard unforgiving piece of junk and yep they make them in mains to - look at the pn if it ends with "M" toss it in the trash - if it says "micro" on it thats an M bearing and trash it. The V stands for Vandervel - a old time bearing mfgr from the olden days - their old formula is used in every single 10,000 hp top fuel motor today. They sure as heck don't use an M bearing!
If the rod mfgr says 50 wt - thats what i'd use - never run a MGP but thats a billet rod and ought to be good.

 

Michael makes one of the best rods out there, don't freak out when you see the torque specs, as he uses, i believe the best rod bolts going.

 

Hindsight we kicked a rod out once because we had a clutch imbalance and didn't know it, maybe you do too?

-warped flywheel?
-floater tabs wore too much?
-stands wore too much?

Also, make sure the floaters are on the stands like they are supposed to be and not off in rotation.

 

Ok we have pulled the engine apart and had a few people who know more than I do look at it and we found that the rod was cracked through the bolt hole on one side the hole had been pounded out not stripped so we came to the conclusion that the rod cracked first causing the bolt to loose tension and rattle around in the hole until it fell out which led to the cap peeling off. After talking to a few people we have heard that leaving rod bolts torqued up for a long period of time can cause this problem, this is a big possibility as this engine was someone elses spare and had been sitting in there trailer for a while. Has anyone else come across this problem?

 

After talking to a few people we have heard that leaving rod bolts torqued up for a long period of time can cause this problem, this is a big possibility as this engine was someone elses spare and had been sitting in there trailer for a while. Has anyone else come across this problem?

|About 2004 I purchased a new set of C & A rods from them. I stored them in the box until about 2012 and decided to sell as I was never going to use them. When I took them to Robert Reehl he looked at them and at all 16 bolts the rods had cracked 1.5 inches up the rod. They were junk !!