Looking for a set of 6" small block rods.

Both Scat & Lunati have several to choose from. Looks like the Scat rods are advertised as being stronger.

I haven't looked at Eagle rods very much.

Anybody familiar with all 3 & have a preference?

I'm collecting parts for a #509 400. I have a Scat cast steel, 6" rod, internal balance crank. I also have a factory 400 crank that needs to be turned 20/20.

One of the local machinist told me he prefers to use the factory crank over the Scat cast steel crank. I was thinking the new crank would have to be an upgrade over the factory crank?

Wanting to build a quick pump gas street car with this engine.

Thanks for any replies.
~JM~

Looking for a set of 6" small block rods.

Both Scat & Lunati have several to choose from. Looks like the Scat rods are advertised as being stronger.

I haven't looked at Eagle rods very much.

Anybody familiar with all 3 & have a preference?

I'm collecting parts for a #509 400. I have a Scat cast steel, 6" rod, internal balance crank. I also have a factory 400 crank that needs to be turned 20/20.

One of the local machinist told me he prefers to use the factory crank over the Scat cast steel crank. I was thinking the new crank would have to be an upgrade over the factory crank?

Wanting to build a quick pump gas street car with this engine.

Thanks for any replies.
~JM~

Hi JM, toss the G.M shaft as far as you can and don't look back. Both the "Eagle" and "Scat" rods are off-shore pieces and will serve you well, but really shouldn't be compared to the "Lunati's", which would be the best pieces of the three you mentioned. The "internal-balance" is the ONLY way to go. It'll give you more options with respect to the balancer AND flywheel. And you don't "eat" up HP trying to spin-up "dependent" dampers and flywheels. Thanks, Gary in N.Y.

P.S. In your particular unit here I would recommend NOT using the "Lunati's" only due to the cost factor AND you'll be using a "cast" shaft. The rods would be "over-kill", but as I stated above they are by far the better of the three! Take the money saved on either "Eagle" or "Scat" and put it elsewhere, unless of course you can get the "Lunati's" for a better price.

You might want to consider Crower Stroker Sportsman rods. On par with the Lunati units, made in USA not Communist China like the Scat, Eagle, and other "cheap" rods.

I've got the Crower units in my engine, but in a 5.7" length.

http://www.crower.com/misc/m_cat.shtml

Im not trying to sell parts in the forum on purpose but I have a new Lunati 5.7 racer series crank if you want to go that route. I will sell it at a price that is comparable to the china stuff . PM Me if you are interested I don't want to turn this thread into a sales ad.Thanks

Thanks for the replies.

I'm looking at these rods.
http://www.holley.com/LHD1.asp

I see that they are rated at 550hp. I also see that the Scat rods are rated to 600hp. & above.

Even the Scat rods that have the same size rod bolt is rated higher than the Lunati.

Are the Scat rods ratings inflated?

How much should I be willing to spend on a unused set of the Lunatis in a best offer situation?

~JM~

Thanks for the replies.

I'm looking at these rods.
http://www.holley.com/LHD1.asp

I see that they are rated at 550hp. I also see that the Scat rods are rated to 600hp. & above.

Even the Scat rods that have the same size rod bolt is rated higher than the Lunati.

Are the Scat rods ratings inflated?

How much should I be willing to spend on a unused set of the Lunatis in a best offer situation?

~JM~

JM,

What is the intended HP, RPM, and usage of the engine?

On a 500-600 HP SBC, I would use rods in this order:

1.) http://www.holley.com/LAD1.asp or Crower Stroker Sportsman w/ capscrew

2.) Eagle or Scat H-beam with ARP bolts

3.) Scat 4340 I-beam with 7/16" ARP cap screws and profiled beams.

If you are going to be at the track every weekend I would go with the Lunati Pro Mod or Crower Stroker Sportsman.

If you are shooting for the 450-500 HP range and are planning mostly street duty with an occasional trip to the track, save your money and run the Scat I-beam.

I see that they are rated at 550hp. I also see that the Scat rods are rated to 600hp. & above.

Ratings mean almost NOTHING unless they tell you what RPM, stroke length, and piston/pin weight is. Since they don't give you that info, the spec is meaningess.

Oh, yeah. I said in my earlier post that the Crower rods were on par with the Lunatis. I thought you were looking at the more expensive Lunatis. The Crower Stroker Sportsman are nicely upmarket from the Lunati "Street Race" line.

JM,

What is the intended HP, RPM, and usage of the engine?

On a 500-600 HP SBC, I would use rods in this order:

1.) http://www.holley.com/LAD1.asp or Crower Stroker Sportsman w/ capscrew

2.) Eagle or Scat H-beam with ARP bolts

3.) Scat 4340 I-beam with 7/16" ARP cap screws and profiled beams.

If you are going to be at the track every weekend I would go with the Lunati Pro Mod or Crower Stroker Sportsman.

If you are shooting for the 450-500 HP range and are planning mostly street duty with an occasional trip to the track, save your money and run the Scat I-beam. From what i hear "I" beam rods are stronger by design than "H" beams. I put Olivers in my 540 when it was built and they have been good so far.

Look at the ratings for similarly priced H and I beams, you will see H-beams are usually stronger. This goes out the window when you start talking about billet stuff. In the lower priced stuff the H-beams are usually stronger.

Isn't an H-Beam much heavier than a comparable I-Beam?

I also read somewhere that the capscrew I-Beam rods have more clearance when building a 6" rod sbc 400/406.

~JM~

Typically an I beam is lighter on the piston end of the rod, and this is what you want. Less reciprocating weight.
As far as strength goes, on a 450-500 HP motor "I" would use a Scat I beam capscrew rod.

Yes, typically an I beam is lighter. It all depends on what you're doing and your budget. If you have $800 for your rod budget then by all means buy billet I beams. The engine in question is going to hace a cast steel crank, so no need to get to crazy with the rods. Either I or H-beam will do the job, buy the one you can get the best deal on.

Isn't an H-Beam much heavier than a comparable I-Beam?

I also read somewhere that the capscrew I-Beam rods have more clearance when building a 6" rod sbc 400/406.

~JM~
=
Yes the Scat 7/16" I beam capscrew has more clearance in a stroker, it has more clearance at the cam than a stock 400 rod.
This would be my rod of choice for you.
They are excellent rods for the money & very strong.
And all finish machine work on them is done in house by Scat in LA.
For less than $300 this is a nice piece.

As was posted above, anyone who rates a rod in HP with no regard to reciprocating weight & RPM is in the politest of terms,,,, full of crap.
HP does not break rods, RPM & weight do.
Almost all rod or bolt failures are in tension, not compression.

Rod weight 101 :D
First,, rod weights tend to vary & you cannot say one design is heavy & the other is light.
It depends,,,,

I balanced three sets of Scat 7/16" 6" I beam capscrew rods yesterday & the weights were 590, 612 & 608
The pin ends were 159, 169 & 161

In the past few months here are a few more measured weights.
A set of 5.7" H beams were 613gms
6" H beams were 627gms
Pin ends 179 & 186

Two sets of Oliver I beam Billet 6.200" rods were 646 & 648gms
These were 2" crank end.
Pin end 185 & 187
A set of Oliver forged 6" were 677gms
Pin end 188
Manley Sportsmaster 6" I beams were 561gms
Pin end 155

...The engine in question is going to have a cast steel crank....

That is correct. Although lately I've been second guessing myself about not buying a forged crank.

I'm trying to build a reliable, well mannered, pump gas engine with 450 to 500hp.

I've also been thinking about N2O lately. I'm concerned about a cast steel crank & cylinder wall thickness though. N2O may not be wise for a 2 bolt main 400 block.

Anybody want to take a shot at suggesting some forged pistons & rings?:D

Thank you everyone
~JM~

I purchased the Pro Tru forged pistons made by Wiseco. For my 383 6" rod motor. very nice piece and light. My machine shop buddy has used them with good results. I bought them of ebay for $460 rings included. I was going to go with hyperutecic, but after ready many posts on here about how many were failing, I spent the extra $$$$$

We ( sons and I) have used everthing available thru the years, currently running 355" SB, 383" SB, 434" SB, 580" Dart BB and 635" Big Chief. Info above great. The China stuff is a big step forward thru the last 5 years, my opinion is its better than the high dollar stuff of 5+ years ago. Would question using any motor builder preffering a stock 400 cast crank for any thing, and really doubt any old stock 400 shaft would pass magnaflux with out stress cracks. The cost of magnaflux, grinding and polishing, chamfering plus having to deal with worn seal surfaces makes a stock shaft worth only scrap. Find a new motor builder that is up with the times.

Bob Hauk

The rod manufactures wouldn't give a HP rating on rods if it was their call. People ask all the time "how much HP is a rod good for", so they are sort of forced into it.

You also have to take into account fatigue life. An oval track application is much more harsh than a drag application typically.

If you gave all the equations and variables to most people, the manufactures would have to put up with a lot of issues.

Every part has a fatigue life, higher quality buys more time. Once you've narrowed it down to a few rods that will handle loads at your desired rpm, your goal should be to pick the one that will give you the most cycles. Oliver is generally at the top of most engine builder's lists. Near the top you generally find Lunati and Crower as well. Manley makes some very good sportsman rods, too. IMHO, Scat has the best bang for the buck with their Pro Series 7/16 capscrew rod for smallblocks. It doesn't make much sense to me to use a cast steel crank with Oliver rods, I agree with the above recommendations for the Scats. Good luck!

Looks like I bought some rods.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=160004286521

How'd I do on the price?

Thanks
~JM~

Looks like I bought some rods.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=160004286521

How'd I do on the price?

Thanks
~JM~
=
Fair,
That is the same rod the Scat & Eagle sell & is the lower priced 3/8" capscrew one.
It is an ok rod but I quit using them about 4 years ago in favor of the 7/16" capscrew ones that are much better with more clearance
That is about what that rod sells for from Scat.
=
This is my rod of choice for the less expensive stuff.
As you can see it is a much nicer piece & only a few dollars more from me at least
http://wsm.ezsitedesigner.com/share/scrapbook/19/190264/Scat2.JPG

http://wsm.ezsitedesigner.com/share/scrapbook/19/190264/Scat1.JPG

Nice buzz kill.

I thought the Lunatis were made in the USA & stronger. That's what the description reads. Now you tell me I just bought inferior Chinese rods.

~JM~

EDIT: Lunati catalog claims they are forged in the USA.
http://www.holley.com/BrowseCatalogs.asp?Catalog=Lunati&Page=267

Nice buzz kill.

I thought the Lunatis were made in the USA & stronger. That's what the description reads. Now you tell me I just bought inferior Chinese rods.

~JM~

EDIT: Lunati catalog claims they are forged in the USA.
http://www.holley.com/BrowseCatalogs.asp?Catalog=Lunati&Page=267
=
They may be, I cannot disprove what they say,
All I can tell you is what I am looking at & they are identical to the cheaper rods sold by Scat & Eagle but say USA on them.
Guess I'll have to take their word for it.

Hi JM you made a good buy, don't "sweat" it! Those rods in the photo are Lunati's 4340 "Sportsman" series. You got an excellent price on them as far as I can tell. We have a few sets on the shelf and they have a slight edge
in overall "quality" to both the Eagles and Scats and probably strengthwise too. The "Lunati" forgings are "reinforced" much more in the area where the end of the bolt and threads are than the pictured ones in the earlier post. They use 185,000+ PSI cap screws and have an Ampco bushing in the pin end. It's called a "Street Race" connecting rod.

(Add) These pieces are the equivalent of the "lower level" Crower rods.

There's absolutely nothing wrong with them for your setup, they'll give you some execellent service. We've used them in many units well above 700 HP with not one issue. Thanks, Gary in N.Y.

P.S. You really can't see the photo too clearly in the "link", but on the beam it doesn't say "Made in USA", they are made here, but what it says is "Lunati USA".

http://i16.photobucket.com/albums/b28/GOSFAST/PES%20Engines/th_LunatiRods.jpg (http://i16.photobucket.com/albums/b28/GOSFAST/PES%20Engines/LunatiRods.jpg)