Tag: RPM rods

RPM connecting rod analysis – part 2

by on Nov.28, 2012, under Mods, Parts

It’s been almost 1 year since I received my RPM rods. When I received them I wrote about their appearance out of the box.

This post is a bit of a follow up. So far I am happy with them, especially for the price. However, I have only 2 miles on my motor so I can’t comment yet on longevity.

Shortly after I received the rods I went to a friend’s machine shop to end balance the rods. I had been under the assumption that the reason these rods were so inexpensive was because they would require final machining and balancing. As it turned out all rods were already within 1g of one another and required no machining.

One thing you will want to check is wrist pin bushing clearance. Mine were all fine except 1, which was a bit tighter. I ran it because it didn’t seem overly tight and I was told that it felt normal and the bushing would break in. We’ll see how it goes. If you assemble them and they are too tight then you can have a machine shop open them up.

As I mentioned in my previous post, the RPM rods come with ARP bolts & assembly lube. I want to point out that the torque instructions that RPM includes for the rod bolts is incorrect! They incorrectly list the bolts as 3/8″ when they are in fact 5/16″. The proper torque, according to ARP, should be 32 ft/lbs and not the 50 ft/lbs listed by RPM.

I believe these same H-Beam style connecting rods are being sold by several other vendors. One includes Nick Audilee @ ProjectB5. The pictures he has show on his website are identical packaging & wrapping. He prices his at $650.

Leave a Comment : more...

RPM connecting rod analysis

by on Feb.02, 2012, under Mods, Parts

I have discussed off-brand connecting rods with several people in the B5 S4 community and many believe all H-beam rods come from the same Chinese source that supplies IE, VAST, Rosten and a few other companies. I found one source, Racing Parts Maximum (RPM), that sells these rods for $390 shipped with ARP 2000 bolts. I ordered them last week and yesterday they arrived from California.

A visual inspection shows these rods are very similar, if not the same. We will see how they work out in the engine. If they fail, oh well.

The rods came with a calibration sheet from RPM that included crankshaft and pin end weights. I will be rebalancing them myself to verify.

The RPM rods also come with ARP 2000 bolts. These bolts cost $140 if sourced independently so it is a big savings to have them included. There has been some speculation on the forums that these bolts were Chinese fakes but they have ARP markings and appear to be quality. A rep from ARP confirmed they were authentic.

I weighed two of the rods (without bolts). They were 522 grams and 523 grams.

This post has some comparison rod weights:

  • Stock 2.7T rod/no rod bolt: 529 grams
  • Pauter standard 2.7L rod/no rod bolts: 530 grams
  • VAST standard 2.7L H-beam rods/no rod bolts: 515 grams
  • VAST custom 3.0L stroker H-beam rod/no rod bolts: 479 grams
  • Rosten Connection Rods/no rod bolt: 542 grams
  • IE Connection Rods/no rod bolt: 555 grams

So far, so good. I’ll post more info after they’re balanced and installed.

Leave a Comment :, more...

Looking for something?

Use the form below to search the site:

Still not finding what you're looking for? Send me a message on AIM!