After reading Hot Rod's article on buying the correct pistons, rods and cranks i am a little gun shy now to use the new Scat 4130 connecting rods that i purchased. The article states that 4130 material is only good in thin sheets and tubing and is not suitable for forged or machined pieces. Will somebody get this straight for me. Bill Mitchell has been using 4130 cranks in all his crate engines for quite sometime and they seem to hold up fine. The engine that i am building is a hp street engine that will never see 7000 rpm but according to the article i would have been better off to rebuild the stock rods which are made of better steel.

Take what you read in magazines with a grain of salt. As many here will agree they don't always tell the whole truth. They are easliy swayed by $$$ of the advertisers and manufactures. While I do not have specific data on 4130. I would seriously doubt any of the big engine builders or manufactures would use it if it weren't any good. They have to warranty the stuff. I haven't heard of any failures due to a crank or rod being made out of 4130. I didn't read the article yet but, are you sure they aren't talking about chromoly?

Royce

I also read that article and liked it. I didn't read too much into exactly what type of steel my parts were made of, but I looked at the charts at the end of the article that laid out in general what "level" of quality matched what type of intended use. I thought it was fairly helpful.

I think your Scat rods, according to the charts, are good for street/strip action just like you plan.

Don't forget different manufacturers sometimes have their own variants of different alloys for different applications --- I seriously doubt that your OEM rods are actually made of better steel than your Scat rods.

[This message has been edited by Eric68 (edited 01-17-2003).]

This is what i have always understood Eric but if you read the section that rates the steel alloy Hot Rod is stating that 4130, one of the best known of the chrome-moly steels will not heat treat properly to be used in a forging or machined piece. Also if you notice the chart for rod selection 4130 is completely over looked as being a suitable rod or crank material. I just got off the phone with Scat and they are at a loss as to what Hot Rod is trying to say. I am sure that i am not the only one to read the article that has either purchased or is using a set of 4130 rods or crank. I don't know about you guys but it would really **** me off to know that i just plunked down over 200 bucks for a set of rods and then paid for the balancing and put an engine together with a defective product as Hot Rod has stated. Scary!

SCAT is one of those $$$ advertisers, so you can expect that Hot Rod will clear the air up some how in the near future.

Heck, GM used cast-iron rods in a lot of lo-rpm big time. hi-po engines in the past!!

Check out Pontiac's...

Arma-steel rods were cast as well... Cad's???

Oh, the dollar can slant most anything!!! pdq67

Most connecting rod problems can be traced to low quality rod bolts. ALWAYS step up and get good quality (ARP or similar) rod bolts.

Does Scat actually make a 4130 rod? Their web page states 4340 for both their I and H beams??? Most good aftermarket rods seem to be made of 4340??? I'm I missing something here - did Scat just come out with a rod made of 4130? Here is a link to HotRod on rod selection - Not the same as the fore mentioned one but still no mention of 4130.
http://www.hotrod.com/techarticles/82378/
Just trying to get a clear understanding of this post.
Later,
Tski

Yes, Scat makes a 4130 forged I-beam rod with ARP waveloc bolts or you can them with a 7/16 capscrew, they also make cranks out of the same material. I have been using their 4130 I-beam rods for quite sometime so no, they are not new. The capscrew version is new. Go to their website and click on the 4340 rods and the others are listed there. I also noticed that they completely ignored 4130 in their rod selection chart, but why would they, they have stated that it would not be wise to use this material in connecting rods or anything else other than thin sheets or tubing. According to Scat 4130 has a much higher tensile strength than stock rod material. We will see what Hod Rod has to say about it's statement, stay tuned.

[This message has been edited by mwcox (edited 01-19-2003).]