CAT products. Have you used them?

[alb84]

There are several CAT products available for use on our engines. I am wondering if your experience with them was acceptable or not. The crank shaft, girdle, and rods to be more specific. Did the crank fit into the block correctly? Was the girdle flat or warped? I am being told there are hundreds in use without these kinds of problems. Please speak up if you have used them. Thanks
Danny

 

[NC87GN]

I am currentyl running a CAT 4340 forged crank. It was not a drop in. I had to to machine the back of the crank where the 'lip seal' on the crank rides, in order to fit into the rear cap. Other than that crank run-out, end play, bearing clearances were pretty good. For the money and strength I am not complaining.. HTH

Mike Banas

 

[alb84]

So did you cut the lip off, or modify the cap? When you say bearing clearances were pretty good does that mean they were all within a tenth or so, or did you have to size the rod and main caps to each journal to get them all the same? Did you talk to your parts supplier about the lip being in the wrong place? Any body else had this problem, or others with the crank or girdle? Thanks for the reply.
Danny

 

[NC87GN]

Hey Dan,
I turned the 'lip' on the crank where the interference was between the rear cap. Had a close friend who is a toolmaker do this for me. Not as bad as you think and I believe any credible machine shop can do this for less than 50 bucks. The rod and crank journals were all within 3-4 tenths. I did buy 2 sets of main bearings though to get the close clearances I was after. Not the cranks fault but there were variations in bearing thickness when I bought Calico coated bearings.. Clearances turned out to be .0016-.0021 after all was said and done..

FWIW, I compared an eagle crank and a CAT crank, on the bench, and saw very little difference in regards to workmanship. I would use a CAT crank anyday if it helped me save some cash over an Eagle.. HTH

Mike Banas

 

[alb84]

Anyone else have experience with CAT products? I am useing the crank, and the girdle. The main journals were the inconsistent ones on mine. The block was align honed and decked. Then the machinest did some hone adjustments to get them all within 2 tenths. The rods were idividually honed to acheive no more than 1 tenth variation. The rear of the block and cap were machined to accept the incorrect placement of the oil slinger to assure proper oil control at the rear main seal. The Girdle you would expect to have some clearancing to make it fit, but I have a whole story coming on that. I am not trying to degrade CAT products, or vendors who sell them. I am just trying to get the extra work involved with using them documented so people know what to expect before they start the project. There has to be more people out there with experiences to relate. Later
Danny

 

[Rodney87GN]

My motor is at Weber racing being built and I'm also using a Cat crank. I'll let you know more details about bearing clearances, etc when I get it back soon. But Bryan talked to me about the rear cap/seal issue. They also machine the crank flange where the flexplate bolts up so it will sit flat and true to the crank.

 

[imjoesnuffy]

I am happy with the CAT girdle:smile:

 

[alb84]

I am useing the CAT SFI flex plate. It doesn't fit on the CAT crank or the stock crank. The hole is too small. So you say the mateing surface on the crank where it meets the flex plate is not flat? Looks like I'll be taking it back out and sending it back to the machine shop again. You see, this is stuff we need to know beforehand. Thanks alot for the info.
Danny

 

[Grumpy]

I am useing the CAT SFI flex plate. It doesn't fit on the CAT crank or the stock crank. The hole is too small. So you say the mateing surface on the crank where it meets the flex plate is not flat? Looks like I'll be taking it back out and sending it back to the machine shop again. You see, this is stuff we need to know beforehand. Thanks alot for the info.
Danny

hmmm.. I have 2 engines with CAT flex plates on with no problems .. crank and rods take a little work BUT thats why ya have a good shop do the work

 

[noahzark]

i used a cat crank in my build ...the price was right...although def. not a drop in by any means...the flex plate did not sit flush on the crank and i had to radius the flexplate slightly...i also had to have a woodriff key fabricated by the machine shop for one to fit in it...i used k1 rods as well and they had some small side clearance issues ...which i hand sanded down the sides a bit in order to get the right clearance...ill have to say this is all pretty much the norm when you start buying aftermarket parts from 15 different companies...its kind of like a bad jigsaw puzzles you have to force everything to fit properly...these cars remind me of custom harleys...lots of headaches but all worth it in the end...noah.

 

[alb84]

I had no problem with side clearance on the K1 rods. I haven't had a chance to throw a dial indicator on the mateing surface of the crank to see if it is flat yet. I thought I would be dropping it back into the car this week end. I got stuck baby sitting the grand kids instead. Anyone else have anything to add?

 

[ijames]

Does anyone sell woodruff keys for the cat crank or does everyone individually need to go get a machine shop to modify one for them?

 

[Turboholic87]

I ended up having to do a lot of work on the CAT girdle. It was warped .010" corner to corner so I had to have a machine shop blanchard grind it -$75. The bolt holes on driver side pan rail were off .050" and I machined these to fit at home on my vertical mill for no cost. Even purchasing new ARP hardware I was below the cost of the RJC unit but in retro spect with the time I spent I would have been better off with the RJC plate.

With the CAT crank I had to wallow out the bolt holes on the flexplate and chamfer the center hole. Reading this post I'm a little worried what else I'll have to do once the block comes back from the machine shop.

I think it's a shame that these parts are so poorly made. All it takes is a quick quality check to make sure the parts are within spec before they leave the factory. Are they just in such a hurry to get them out the door and make a buck that they don't care if they fit??

 

[cruzn57]

no complaints, but............

I'm very picky ....
and had to cut crank 10under, as wasn.t as round as I wanted,
rods had to be clearanced, (side clearance was off)
girdle wasn't as flat as I liked,
flywheel is fine,
all in all, I'd buy cat products again, there ok and price is great.
strength??? we'll find soon enough!

 

[Rodney87GN]

Weber Racing has the correct woodruff keys for the Cat cranks.

 

[Rodney87GN]

I am useing the CAT SFI flex plate. It doesn't fit on the CAT crank or the stock crank. The hole is too small. So you say the mateing surface on the crank where it meets the flex plate is not flat? Looks like I'll be taking it back out and sending it back to the machine shop again. You see, this is stuff we need to know beforehand. Thanks alot for the info.
Danny

I should've clarified that Weber machines the flexplate register on the center of the crank so the flexplate will sit flat, although they do check the crank flange for trueness anyway.

I wouldn't take out the crank yet. You should be able to check it on the block with a dial indicator. You might be okay, just double check. I'd hate to see you pull out the crank if you don't need to.

Also I'm using the stock flexplate that's been neutral balanced so I don't have any experience using the Cat one.

 

[corymc]

I ended up having to do a lot of work on the CAT girdle. It was warped .010" corner to corner so I had to have a machine shop blanchard grind it -$75. The bolt holes on driver side pan rail were off .050" and I machined these to fit at home on my vertical mill for no cost. Even purchasing new ARP hardware I was below the cost of the RJC unit but in retro spect with the time I spent I would have been better off with the RJC plate.

With the CAT crank I had to wallow out the bolt holes on the flexplate and chamfer the center hole. Reading this post I'm a little worried what else I'll have to do once the block comes back from the machine shop.

I think it's a shame that these parts are so poorly made. All it takes is a quick quality check to make sure the parts are within spec before they leave the factory. Are they just in such a hurry to get them out the door and make a buck that they don't care if they fit??

i also had to get work done with the cat girdle would have been better off buying a RJC. I have heard it before but i didnt like the cat girdle and neither did my machine shop and thats my opinion. Im glad i spent extra money on eagle crank and rods becuase they fit no mods.

 

[gnxtc2]

From the previous postings, most had to do some type of work to the CAT products. Although the CAT is cheap at first but......in the end you wind up paying the same if you bought the American product.

CAT=China=no pride/no quality control

Billy T.
gnxtc2@aol.com

 

[Race Jace]

just a little info that will help you in your decision making. no fluff or BS.

cat

 

[S2V6RACER]

I friend of mine just had a 109 block done using a CAT girdle from Full Throttle and they had no issues with fitment what so ever. He upgraded his studs to ARP and still had way less than the RJC girdle.

I wouldn't hesitate going with the CAT girdle.