I'll second that.

You might also add improper clearances or assembly (human) errors.

 

Scat Budget 383 cubic inch Rotating Assembly
4.030" Bore SRP -5cc dish pistons, 3.75" stroke Scat cast crank, Scat forged 6.00" I-Beam Rods $1279.92

this is what im looking at


and here are some other kits that cmotorsports sells. all im looking for is something that will hold 500rwhp


Scat 383 cubic inch Rotating Assembly
4.030" Bore SRP -5cc dish pistons, 3.75" stroke Scat cast crank, Scat forged 6.00" H-Beam Rods $1498.95


Eagle 383 cubic inch Rotating Assembly
4.030" Bore SRP -5cc dish pistons, 3.75" stroke Eagle forged crank, Eagle forged 6.00" H-Beam Rods $1749.97

 

Sounds like you've either got your head chambers opened up pretty well...or are going to be running some pretty high compression?

That's the setup I have...check out www.adperformance.com or send an email to scatstroker@hotmail.com you can get it for quite a bit cheaper (Unless that cmotorsports kit comes with rings/bearings, which you didn't mention)...

 

thids is not that bad and thats all forged stuff. but it doesnt say if its one peice rear seal, or mention anyhting about lt1

Scat 4340 Forged Crankshaft

Scat 4340 5.7" H-beam rods (6" rods available!)
Probe, SRP or Ross forged pistons
Wrist pins
Spirolox
Rod Hardware

Chevy "355" 3.480 Stroke - Price: $1375.00
Chevy "383" 3.750 Stroke - Price: $1399.00
Chevy 400 4.155 bore "407" - Price: $1399.00

 

and what is spirolocks

 

They're little finger cutting pain in the *** spirals of metal that hold the piston pin in for a floating pin piston setup.

 

so how good are the scat forged rods. i havent heard much about them. and now that i think about i havent heard much about there forged cranks either.

 

Definitely!

As for bottom end, I can imagine seeing statistics on component failure of street engines in the ~1.5hp per cid range. I'd bet that less than 1% are the result of poor materials. Poor tolerancing, machining, build errors and/or oil system failures probably account for the rest.
A little vigilance goes a long way. I am amazed what people will pay for a crank, connecting rods and pistons in these types of builds.... even more amazed that many of these same people won't invest in a filter case cutter, filter magnets etc., and learn how to use them.

I've been really impressed with Scat's lightweight and billet cranks... they are nice pieces. The Scat I-beam rods are probably the best deal going. You can rebuild a set of stock rods or spend a few bucks more and buy the Scats. Polish the beams and upgrade the bolts.... it's a no brainer IMO.

-Mindgame

 

Usually human error is what causes a motor to go south.

MG better yet Scat does the polish the beams and upgrade the bolt tricks for you! For $280-$300 a set that's a steal.

As for H vs. I I have to look at price too.

Strength for cheap = Scat I beams hands down.

Lightweight and strong for a low power circle track or a moderate street motor (600hp) = Eagle Lightweight H beams

For Cheap and Strong for a Street motor = Eagle H Beams and L19's if I need them. This is usually for Blown/Turbo or N2O motors.

If I am going RPM and Cheap, then a Eagle H with standard bolts will do since $430 a set is pretty dam good.

Once I start caring about RPM and lots of power or load. Then I have to like Olivers. It's hard for me not to say they are close to the ultimate. That and Arrow is VERY impressive.

There are a lot of rods between Eagle H's w L19's and Olivers. Manley, Lunati and Howards all make rods that fit right in there and they will take some abuse.

I just have a problem with spending lots of money on expensive bottom end parts in street motors. Now if we are talking about 1000hp and Bowtie blocks, then I'm not. LT1's have the problem of having a block that is not as strong as the parts you can put in it.

Bret

 

what about the rods in this thread? overkill for the LT1 block... aluminum ceramic composite beauty and only $1600 for a set
http://bbs.hardcore50.com/vbulletin/...d.php?t=19003;

p.s. i didnt see him mention anything about CMS trying to sell him a different crank.... but you're prolly right Bret

 

[QUOTE]Originally posted by RealQuick
[B]CM told me that They wouldnt recommend a forged eagle crank or the eagle h-beam rods for 600+rwhp.

This is interesting because they told me they have LT1's making 800+ rwhp using Eagle H beams probably a year ago.

I can Tell you My Eagle 4340 Lightweight crank balanced very easy and I thought it looked good.
I also used the Eagle 4340 H beam rods with L19 bolts.

I have no experience in this but I talked with several local dirt track shops that claim the Eagle stuff will take a lot of abuse

 

Some of the high powered LT1 owners on this site has also said that the eagle stuff will handle 600+rwhp no problem. I have the upgraded bolts and I have oliver billet splayed caps. Should handle my blown 383 nicely.

 

Purchased last year a scat 9000 383, with 5.7 I-Beam rods from CM. They did not oppose using for LT1 rebuild. Used Wiesco forged pistons from Poly-Dyn ( come coated on top and sides for about same price as Summit or Jegs non coated). Did internal balance on rotating assembly. No problem. Should take 550 hp @ 6400 rpm with no problem for my application. I did not have to grind block for the additional stroke. Did remove the oil baffle plate. Suggest you look at oversized (.001) main bearings with this crank, to bring the clearance down to .0015 for good oil pressure. For the money, and under 700 hp, couldnt find a better setup. Look at the latest issues of either Hot Rodding or Hot Rod, I believe, they do a 383 buildup (about 600hp) using the Scat 9000. Will note, the machinist who did the block work, mentioned, a few times he has noticed the Eagle cranks may require more machining. That is why I went with the Scat, plus reading post here and LS1 com, and talking with people with the Scat stuff.

 

Matt LT1,

Is that where your main bearing clearance is at?
I was talking with someone on the board the other day and I mentioned the LT1 manual says clearances between .0009-.0015
and they thought that was way to tight and that they advised .002-.003 which I thought was pretty loose according to the engine class I just took & the manual. Right now my mains are all set at .0015 except for one which is at .001

Maybe Stroker Ace & mindgame will have some more good info in this??