[Redta]

I'm curious to see what everyone thinks about Scat rods vs. Eagle rods. Lets say in a street/strip car with about 550hp. I know the Eagles seem to be the more popular choice, but not sure why.

[Danimal]

Hey Redta,

Scat has been around for years and has had what I thought were the best quality for rod and cranks, however I believe that Eagle puts out a heck of a rod too and they are now very similarly priced so I believe it is a toss up.

I went with the Eagles 6.625 H-beam in my motor (400) as that is what my machine shop used primarily--(Or Crower if yer pockets are deep enought :-)) and I have yet to even fire the engine but I do not generally beat on the engine so they should last forever.

Either way, for a pontiac a replacement forged steel rod is a smart upgrade from the factory cast rods, which are not only heavy buy not designed to run much higher than 5,500 RPM. and as an added bonus you can find replacement Eagle or Scat rods for around $400 /set which is just a bit more than prepping the old rods and replacing the rod bolts with new hardware.

Anyone else out there have any suggestions?

[BILTIT]

I run SCAT's. Dave at SDPerformance assured me they are quality pieces. They looked nice to me but i have never seen an eagle rod in person.

[71firebird400]

I think they're considered about the same. Eagle's are definetly more popular in the Pontiac world. I heard from one guy that the Scat cranks took a little more work to get balanced, but he didnt have any comments about the rods.

[Robert Williams]

I have a good friend that runs the Eagle rods in his Super Stock Firebird, he runs the 400" 6X combo in S/S. He runs this engine at 7,500 rpm's and has never had a rod break.

He has won a lot of races with this car, he does put in new rods approx every 3 years. Not bad for a stock factory crank, 2 bolt mains and stock main cap bolts. Lynn, you know who i am talking about, he could not make Indy this year, he will be at Englishtown this week end.

[smagnotti]

H beam type rods like the Eagles kick up a alot more oil windage than a I beam type rod.
I would not be all that surprised if it amounted to a 20 HP loss in a 7000 rpm motor built without a crank scraper!

[Billy177]

Scats here been fine for 25k hard miles. I got them simply because they are made in America

[RAIV55]

I've used both and strength wise I consider them the same. Scats are closer to spec and I seldom have to rework the big end. I've had two failures with the ARP 8740 bolts used the Eagles. From what i understand my experience is rather rare but now I order with the L-19 bolts since I don't want to tempt fate. Scat's going in race engines get the ARP 2000's.

It's my understanding Scats are forged in China but machined in the US.

[Mr. P-Body]

I have experience with both. Both H-beams are made from the same forgings. Yes, imported. Sorry, dude, Scats are NOT American-made...

What makes Eagle different than Scat, Elgin, C.A.T., Star-Galaxy, and all the other generic H-beams, is the "3D" feature. That is, an extra rib down the middle of the beam, creating two smaller radii instead of one large one., According to a metalurgist friend, good for about 15-20% sheer strength from a "side load". This is propietary to Eagle.

If you place both rods next to each other, the added attention in the finish quality of the Eagle is obvious. We have never had a rod failure due to the rod or the bolt, when using Eagles. We have engines well over 700 HP with them. A couple BBCs are bumping 1,000. Also, the bolt in the Eagle, though the same rating, is about .200" longer than those in the generi-rods.

There was a local builder using them a couple years ago, that went through several rod bolts breaking. It turned out, his mics were out by about .002", and his torque wrench had NEVER been calibrated. He was torquing the 8740s to over 70 lbs. That'll do it! We've also seen a few of the 2000 bolts broken in BBC engines brought here for repair (not our builds). We use a stretch guage for those.

The worst issue to date with the Scat, has been one that the little end didn't return to proper size after heating (pressed pin). The pin "walked", putting a groove in the cylinder wall. Scat insisted we were "doing it wrong". Apparently, Scat disagrees with SAE, Sunnen, GM, Ford, Dodge, etc. We're supposed to press the pin through the rod "dry", allowing the piston to be subjected to about 20 tons of pressure. WRONG!!! I hate it when a salesman tells me I don't know what I'm doing, and HE does, because he works for Scat (or whomever the guy might work for)... His biggest piece of "ammo" was "If you buy a GM crate engine, it has Scat rods in it!" I guess we're supposed to be intimidated by craters...(:- I reminded him that GM buys parts based on bid, not necessarily quality. He no longer wanted to talk to me! We're not supposed to know these things...

On that subject, while at Indy, GM had a 625 HP 572 on display. It made 595 lb. ft. of torque! I hurt their feelings when I told them about our 461s ("stock block") making that much HP AND 650 lb. ft. on the same 93 octane. The younger GM guys have no idea what our beloved Injun is capable of! I still say, the best street motor around!

To sum it up, any of the H-beams are better than any of the I-beams, possible exception, Crower Sportsman. I just received (today, Cliff) a set of the "Tomahawk" rods drop-shipped from Ace. These are the first ones I've seen, so I have no opinion as of yet. They're purdy...

As of now, we've not seen a better rod for the money, than Eagle. Since they lowered the price on the Pontiac, it means two things. First, they ARE paying attention. Second, the Pontiac market has grown to the point where they WANT to be a big player in it. Maybe, another crankshaft line is on the way! We shall see...

Jim

[Redta]

thanks for all the input. Scat rods seemed to priced right around $400-$450. The Eagles however, are all over the place. Anywhere from $429 (Butler) to almost $700. Why is that?

[Billy177]

"Complete manufacturing capability right here in the USA, with 2 state of the art American GFM crankshaft milling machines, 25 CNC machining centers, over 15 crankshaft grinders and polishers, a complete production line for rod finishing and much more."

Directly off scat's website, so at least they are machined in the USA

[Ken -Ace- Brewer]

Originally Posted by Mr. P-Body

To sum it up, any of the H-beams are better than any of the I-beams, possible exception, Crower Sportsman. I just received (today, Cliff) a set of the "Tomahawk" rods drop-shipped from Ace. These are the first ones I've seen, so I have no opinion as of yet. They're purdy...

They are a good looking piece. The tolerances will be just as purdy!!! :-) My rods are among the lightest and strongest made! Possibly the lightest Pontiac Steel rods on the market! Let us all know your findings. Everyone who has oreded them has nothing but good things to say! Even John Angeles has them in not 1 BUT 2 of his motors!! They can't be to bad!! LOL!!! Bolt torque is 60 ft lbs.

Lets see how they do in the Engine Masters Challenge! :-)

Be Cool,
Ace

[Redta]

Ace,
Can you get the tomahawk rods for press fit pins?

[Ken -Ace- Brewer]

Also Eagle and Scat are both made in China. And BOTH are machined here in the states. The Scat's are machined at Scats facility in Redondo Beach, Ca. The Eagles are machined at Atlas Machine in Harbor City. I have been on a tour of both facilities.

Hopefully that will stop the confusion of where they are machined.

Be Cool,
Ace

[Ken -Ace- Brewer]

Originally Posted by Redta

Ace,
Can you get the tomahawk rods for press fit pins?

Yes we have them now in stock! Alot of people asked for them. I got 10 sets custom made with press fit small ends! :-)

I listen to the needs of my customers!

Tomahawk Rods come in 3 versions! 5150 I-Beam, H-Beam , and Ultra-Lite I-Beams. They are available in Pontiac lenghth 6.625 and 6.7, 6.8, and 7.1! The 5140's come in a bushed version for the 6.8 length! YES! There is a budget stroker rod! :-)

The Ultra-Lites in the Engine Masters started off as press fit. I say started becuase Mr Culpepper is doin some custom stuff for his entry!

Be Cool,
Ace

[Cliff R]

"Directly off scat's website, so at least they are machined in the USA."

I'm skeptical that SCAT machines "everything" in house. Back when the "N" cast cranks were released, we obtained several of them from CAT and SCAT. I sent them to one of the best crank grinders in this area, and he gave me a full report on both of them.

Aside from them wanting mallory metal on the front counterweight where there was no place to put it, BOTH cranks from different vendors had EXACTLY the same issues:

Snout too big, stroke off .001-.003", rod journal out of round, thrust out to maximum, and EXACTLY the same "rough" finish on all the journals. So much so that the cranks "buzzed" in the balancing fixture.

If everyone is doing ALL their machining "custom" in "in house", explain to me why the cranks had the SAME problems from two different vendors, and how did they NOT figure out that the WRONG counterweights were used on the castings so they would be difficult, if not near impossible to balance?

My guess is that the source of the cranks in China forgot to sharpen his stone the day he machined those cranks? I'd imagine they just put a shipping label on the box and sent them out, as recieved from offshore.

If either of those cranks were "custom" machined in house, whoever did it had better keep their day job!.....Cliff

PS: I'm not trying to be super critical about either company, just make sure you check EVERYTHING you buy from EVERYONE.....BEFORE using it.....

[GonicGM]

Originally Posted by smagnotti

H beam type rods like the Eagles kick up a alot more oil windage than a I beam type rod.
I would not be all that surprised if it amounted to a 20 HP loss in a 7000 rpm motor built without a crank scraper!

That crossed my mind. Also, is any oil being pooled momentarily on the H-beam affecting balance?

At same weight, profile maximized for strength, how would an H beam rod be considered stronger than an I beam rod dynamically? At face value, straight tensile and compressive loads, I'd guess it's a toss up. Dynamic loading of rod changing direction near 90 degrees before and after TDC, I'd think the profile of the traditional I beam would better limit flex with the majority of the meat normal to the crank axis. Although, if a bending moment can occur to the rod because the rod isn't centered axially under the piston and/or cylinder pressure loading of piston is not centered axially, I can see the benefit of the meat where it is axially on the H Beam.

[Cliff R]

You'd really have to ask an engineer, to get an opinion on the capabilities of the different types? I've heard over the years that the "H" beams are stronger in compression. They don't have as much meat in the cross section as simliar "I" beam rods. Cut one in two with a hacksaw sometime, they are pretty thin.

"H" beams are very popular, and seem to hold up just fine, at least for the power levels we are at. I've never had any troubles with any aftermarket high performance rods, even the 5140 "I" beams.

The Tomahawk I beams were chosen for this build as we were trying to keep the weights down in the assembly, and still use a steel I beam rod. I saw some at Norwalk, so aquired a set for our new engine. We will be hanging lightweight JE pistons on them. Hoping to get it all together and in the car sometime next month, probably right after all the tracks close down around here!.....Cliff

[Ken -Ace- Brewer]

I fully agree with Cliff! Check everything before assembly. No matter what rods.

Cliff I am sure my rods will work out great for you. Our 428 rotating assembly bobweight comes in at a mere 2080 grams!! I love these rods. And I have to thank Chris the owner of Probe for hooking me up with his connecting rod and crank company. :-)

Be Cool,
Ace

[Bumper]

Too much Vendor loyalty and for me. Is this because Eagle dropped their rod prices to mach the cheaper rods ?