Has anyone on here had a CAT rod or crank break?

[WELTERRACER]

Curious if anyone on here has had any bad luck with a FORGED CAT rod! or Crank!

[yody]

I know this is from the other thread, but it also isn't necessarily a "break? it can be faulty machine work, like the rod ends out of round, or the crank takes huge amount of mallory to balance, or break. Not a lot of guys on this site build their motors their selfs, you might try team chevelle@ chevelles.com I have seen numerous posts there but a search didn't dig up anything for some reason. Also make sure people don't get it mixed up with "Scat"

[yody]

also check nastyz28.com there are a few posts about cat there

[graycamaro]

Are you thinking of useing them for your 700+ hp engine because I wouldn't. We have tryed them in some Modified stock car engines in the past with failure in nearly every case. FYI a modified engine puts out in the neighborhood of 650+ hp NA so for a 700hp supercharged car I would not even consider it.

My boss considers Callies to be the best crank in his oppinion but we use Eagle and Scat as well.

Hope this info will help you in your decision James

[WELTERRACER]

Are you thinking of useing them for your 700+ hp engine because I wouldn't. We have tryed them in some Modified stock car engines in the past with failure in nearly every case. FYI a modified engine puts out in the neighborhood of 650+ hp NA so for a 700hp supercharged car I would not even consider it.

My boss considers Callies to be the best crank in his oppinion but we use Eagle and Scat as well.

Hope this info will help you in your decision James

Did you actually used CAT rods or are you talking SCAT rods..

RPMs are the biggest killer of rods... What RPMS where you running in your modified stock car? (stock cars use alot higher sustained rpms than a street car with ocational drag racing)

[graycamaro]

Actually I was speaking of cat cranks being the failure point in these engines. The number 1 reason for rods to fail as for as spin a bearing is probably do to the fact many engine builder think if the rod is new that must mean it is on size. At the machine shop where I work we comonly have to recondition brand new rods to make them in perfectly in spec. When a customer asks us how much rpm they can turn safely we tell them as much as they want because generally they will run out of their powerband before they will damage the engine.

Stock cars generally turn 7500-8500 with a few guys turning them harder. Depends on the drivers likes, the chasis, and the track.

A guy recently brought in a new 302 Dart block and Cat crank among other parts for us to do some machine work and despite what my boss has told him about our experience with Cat cranks he is still going to use it. The engine is going to be blown and stroked so we will see how it holds up.

How much is the Cat crank and how much is a comparable crank from callies, Eagle, Scat , or Lunatti? Remember the old adadge you get what you pay for!

James

[WELTERRACER]

i paid $360 for the crank and $250 for the rods (H beam).. they are both forged 4340 steel! a similar eagle crank would cost $900 and eagle rods would cost $500

Actually the crank im using isnt CAT is a made by MADDOGRACING(im not sure if it makes it better or not) The crank is supposidly good for applications over 1000 HP and the rods are good for applications over 700hp

My blown engine will not see higher than 7000rpms for short drag stip burts!

[yody]

you can keep telling yourself whatever you want and using !!!! after everytime you mention that your rods are forged steel, but that doesnt' mean anything. And do you really think some place on ebay called "maddogracing" makes cranks?? Just think about it for a minute. YOu are not guaranteed a failure but for a 7000rpm motor with wha 12-15 ilbs of boost at 700hp you are asking for it!! I know what boat you are in right now, you know you shouldn't use those components but at the time you were cheap and ignorant and now you are trying to convice yourself htat it will be allright. Just forget about using those components, and get yourself a scat steel crank/rods. Just resell the stuff on ebay, if you take a small loss, who cares. It will be worth the piece of mind.

[Blown353]

I wish you luck. Have them thoroughly checked out, especially the rods. Don't be surprised if the rods have all sorts of issues on the big end.

If there's anything I've learned over the years after replacing broken parts, it's this: If you buy cheap, you buy twice.

If you keep an eye out, you can often get sweet deals on lightly used high end stuff. I would take used higher end stuff over similarly priced new "cheaper" product lines any day of the week.

Troy

[blown69nova]

I have a buddy who is making 900+ rwtq and hp with a stock Chrysler forged crank and stock block with twin turbos. He has been using this combo for years and has made more than 50, 9sec passes and not one failure! The moral-precision machining, maticulous assembly and careful, methodical tuning! Good luck.

[yody]

yeah, a stock forged crank is way more dependable than some chinese forged stuff, at least scat and eagle stuff is checked and measured in the U.S.
I have heard that eagle has good rods and that their cranks suck
scat has good rods and their cranks sometimes suck but are more likely to be good than eagles

[WELTERRACER]

o.k. Im glad you know it all yody! Like i said before im having the parts checked at the machine shop and soo far soo good!

[yody]

o.k. Im glad you know it all yody! Like i said before im having the parts checked at the machine shop and soo far soo good!

hey, thanks! me too! Well maybe you will prove us wrong or just have a lucky experience. who knows.

[graycamaro]

Yody thanks I wanted to put it that way but I was being nice, It seems like everytime I make a recomendation or suggestion or post my experiences someone always chimes in saying Im wrong thanks for backing me up on this one.

Believe me when I say it is not a matter of who checks out the parts or machines them if you have a crappy part it is a crappy part. You cant make a Cadillac out of a Pinto no matter how good you are. there is a reason those parts are so cheap. Also are you having the assembly ballanced because usually with these cranks it will take alot of work to get it ballanced right or even close to right.

I would take yody's advice and resell the stuff you got and buy new or have fun trying to prove everybody else wrong.
James

[WELTERRACER]

Im a risk taker and i would love to prove everyone wrong.... If she blows up i will be the first to admit the parts were junk... But hey anything has to be stronger than the CAST rods and CAST crank i was using before that DIDNT blow up..

Had i ran the race fuel i was told to use or retarded the timing or ran an intercooler or added the thicker head gaskets i probobly wouldnt have blown up my motor in the first place... BUt im sometimes lazy or looking for a reason to rebuild my worn motor... Pretty much everything on my car has come from either the internet or was purchased thew ebay!

[yody]

I just don't think you understand what we are talking about here, it doesnt' necessarily mean what it is made out of, but how it is made, you could make a crank out of titanium, but if it isn't made to spec and have very high machining tolerances, it will be a piece of crap. Hey you might be fine with the stuff, good luck. Be sure to post up when it does blow though

[SatisTraction]

i know your feelings are hurt but they are telling you the truth. in the end you could have built a much better and longer lasting engine for about $800 more. once it blows you have to start over and you have wasted all that $$$ on scap metal. a crank driver blower (if that is what you are using) is WAY harder on the snout of a crank then any other combination. Go to any performance site with lots of blown cars (www.corral.net) and look at all the pics of cars with broke crank snouts.

[SatisTraction]

repost

[SatisTraction]

repost

[SatisTraction]

how did that happen?

[Ralph LoGrasso]

You may have hit post reply a few times?

[68protouring454]

theres a reason summitt racing carried there stuff for about 2 weeks before they junked it, toom any issues with machining and breakage, take pics when it blows up

[wendell]

I'd run cast GM internals before no name forged seconds that ended up on Ebay. Thats just me. Atleast the GM stuff has design, mettalurgy and QC behind it.

[SatisTraction]

test

[WELTERRACER]

Im surprised Frank from prodigy hasnt chimed in on this thread as i seen on his website that they used CAT rocker arms on JAGARANGS 69 FIREBIRD which is supposed to make upwords of 1000HP with race gas..

I talked to a friend of mine who works at Car Quest who told me that CAT is actually made by SCAT(the company had split) and both scat and cat come from a offshore country! But most people consider SCAT parts as high quality!

Only time will tell.. YOu guys will just have to wait!

[WELTERRACER]

Here is some testimonials from people who have used CAT products..

http://www.catpep.com/about%20us/CATtestimonials.htm

[yody]

Well I feel bad for Jagarang considering the CAT rocker arms are supposed to be one of their worst products. Also I don't think reading testimonials from the manufactures site is going to be very one sided. good luck again, your going to need it!

[Jagarang]

Ouch..didn't know that. I guess we'll find out. They were recommended buy Jim Butler personaly. I trust Jim Butler and Jim Butler Performance and hope it turns out favorably.

[SatisTraction]

at that HP i would only have a set of shaft mounted jesel rockers anything else is a time bomb

[WELTERRACER]

at that HP i would only have a set of shaft mounted jesel rockers anything else is a time bomb


As long as you use screw in studs with roller rockers and stud girldles (like i do) he wont have a problem...

One thing almost every guy i have ever know overlooks is that they think that the amount of HP you make is what breaks parts, but in reallity its the RPM at which you make the HP that breaks parts...

With a procharger you dont need to spin a motor 10,000 rpms to make 700hp.... My motor redlines at 7,000 and i could actually use a smaller cam and only spin it 6000 and still make 7-800hp as long as you add more boost and octain!

People dont think that companys like Lunati and Dart dont have parts fail... BECAUSE THEY DO>.....

A friend of mine told me a funny story last night...... He said... I know a guy(whos name i wont mention) who bought a Dart block, Dart crank, Dart rods etc etc..($12,000 in just the short block) for his pro stock car and then goes out to Thiesens and uses the cheapest oil and oil filter for it, because Thiesens will donate it as a sponsorship! LOL and then he wonders why his engine blows up.... :)

[SatisTraction]

i know why it blows up, because he is using cheap ass parts like someone else in this thread.

[WELTERRACER]

Dart parts are cheap???

[ProdigyCustoms]

OK, we are not going to make 1000 HP with Kevin's car. At anything more then 700 HP it will most likely blow the lifter valley out before the rockers break. The lifter valley is our self imposed limiting factor to keep us from getting crazy.

Jim Butler did swear by the rockers, although I am the first to admit I am not Cats biggest fan. However, breaking a crank is slightly different then breaking a rocker. Seeing as I am not a Pontiac expert, and seeing as Jim Butler is, I thought it best to shut up and let him make the decisions, and keep my personal prejudices to myself.

For the record, my basic operating theory is to spend fair money for good lower end components (guts) because when they go they pretty much destroy anything in site. I have bought budget cranks in the past, only to have to turn them and have them nitrated, which ended up making them cost what a good one would have cost.

With that said, A guy that worked with me has a street race car with a similar engine to mine, 400 SBC, bought a set of Cat 5140 I beams. Put them in out of the box, turns the snot out of it on 450 HP spray, and has not hurt it yet! but then again I hear constant horror stories of other just driving down the road and snap! So, it is probably a craps shot at best.

I wish you luck with it Brian, I respect the fact you are on a budget. I guess if it lets go it wasn't like you had a mountain of money in a high dollar block.

[WELTERRACER]

OK, we are not going to make 1000 HP with Kevin's car. At anything more then 700 HP it will most likely blow the lifter valley out before the rockers break. The lifter valley is our self imposed limiting factor to keep us from getting crazy.

Jim Butler did swear by the rockers, although I am the first to admit I am not Cats biggest fan. However, breaking a crank is slightly different then breaking a rocker. Seeing as I am not a Pontiac expert, and seeing as Jim Butler is, I thought it best to shut up and let him make the decisions, and keep my personal prejudices to myself.

For the record, my basic operating theory is to spend fair money for good lower end components (guts) because when they go they pretty much destroy anything in site. I have bought budget cranks in the past, only to have to turn them and have them nitrated, which ended up making them cost what a good one would have cost.

With that said, A guy that worked with me has a street race car with a similar engine to mine, 400 SBC, bought a set of Cat 5140 I beams. Put them in out of the box, turns the snot out of it on 450 HP spray, and has not hurt it yet! but then again I hear constant horror stories of other just driving down the road and snap! So, it is probably a craps shot at best.

I wish you luck with it Brian, I respect the fact you are on a budget. I guess if it lets go it wasn't like you had a mountain of money in a high dollar block.


Thats exactly right..... I dont have a moutain of money to spend and i wont have a ton of money in the engine either..... and if it holds up i will have hell of a great engine!

THere might be alot of guys on this site with 6 figure incomes or more that might be able to afford $1000 crankshafts and $800 rods and $800 pistons but im trying to do it on a very very small budget and quickly i might add, as i actually like to drive my car.. If i had to build my car according the the guide lines of every person on this website i would easily have $20,000 in my motor! But to be honest there is also alot of guys on here making big power ,without any problems, with stock and or cast parts!

You have to respect me for being willing to try something out of the norm verses spending rediculos amounts of money to do the same job!

[yody]

sorry I am only 25 years old and am unemployed. beat that for a budget!! Well you might get lucky. Make sure to have your machinst triple check everything on the crank and rods, hopefully he is a decent machinist. Also are you having the the motor balanced? You will find out real quick if it is a crappy crank when you get it balanced.

[SatisTraction]

sorry I am only 25 years old and am unemployed. beat that for a budget!! Well you might get lucky. Make sure to have your machinst triple check everything on the crank and rods, hopefully he is a decent machinist. Also are you having the the motor balanced? You will find out real quick if it is a crappy crank when you get it balanced.

yep mallory is expensive

[WELTERRACER]

sorry I am only 25 years old and am unemployed. beat that for a budget!! Well you might get lucky. Make sure to have your machinst triple check everything on the crank and rods, hopefully he is a decent machinist. Also are you having the the motor balanced? You will find out real quick if it is a crappy crank when you get it balanced.


Yes the complete engine is being balanced from the SFI balancer all the way to the aluminum fidenza flywheel!

Its amazing how an unemployed guy can afford $3500 wheels LOL... Im sure you werent unemployed to recently... My girlfriend only makes $7 an hour and i am left to pay for the WHOLE house payment and expenses..

[SatisTraction]

BTW, I would not go with a billet crank but i would do with a forged eagle or scat crank. I know a good scat dealer that could hook you up with some nice prices.

[WELTERRACER]

BTW, I would not go with a billet crank but i would do with a forged eagle or scat crank. I know a good scat dealer that could hook you up with some nice prices.


Thanks for the offer... but, like i said before im willing to take the chance on the parts i have already purchased... the machine shop talked to me today and the motor should be done in the next few days..

Just call me Welterracer the guinee pig... LOL :spank2:

[yody]

Well i worked at home depot as a peon for 2 years if that counts. Also my wheels didn't cost $3500 not even with tires :)

[EFI69Cam]

Scat is the word scientists use for crap. Like "this Lion scat has fur in it"

[derekf]

I think this thread has pretty much run its course.