Will it live?
Thread Starter
Racer
Joined: Aug 2002
Posts: 402
Likes: 0
From: Central IL
Will it live?
I'm building a budget motor for my '55 Chev. to just play around with. I'm going to put an LS1 in it when I re-do it in a couple years, but for now I'm just going to build something cheap so I can drive it. I grenaded the 406 that was in it a while back :rolleyes:
I have some heads, intake, etc. lying around and I may just build a cheap shortblock. I am thinking about doing another 6" rod 406 with a Scat cast crank and Eagle I-beam rods (the cheap ones). The heads I'm going to use are Dart 220's, the cam is fairly aggresive roller, somewhere around 250@.050 and .620 lift. It will be naturally aspirated.
My question is, will the short block live with a two-bolt block, cast crank, and cheap rods? Should I just spend the money on a good forged rotaing assembly? I don't any experience with the Scat cranks or Eagle rods.
I have some heads, intake, etc. lying around and I may just build a cheap shortblock. I am thinking about doing another 6" rod 406 with a Scat cast crank and Eagle I-beam rods (the cheap ones). The heads I'm going to use are Dart 220's, the cam is fairly aggresive roller, somewhere around 250@.050 and .620 lift. It will be naturally aspirated.
My question is, will the short block live with a two-bolt block, cast crank, and cheap rods? Should I just spend the money on a good forged rotaing assembly? I don't any experience with the Scat cranks or Eagle rods.
Burning Brakes
Joined: Dec 1999
Posts: 924
Likes: 1
From: Houston Texas
Re: Will it live? (belair55)
Uuuuuuhhhhhhh.....no!
A lot depends on what RPM you plan on turning in this engine. If you are just wanting to use existing parts no matter what, and you can keep it below 5500 RPM you might be OK, but with that big cam and heads your going to be leaving a lot of HP on the table running it below 5500 RPM. If this is the situation you might consider at least upgrading to some good ARP rod bolts.
If you plan on running the engine RPM to the cam and heads potential, then the 2-bolt block would be OK if it's properly machined, has good wall thickness, and uses ARP bolts for the caps. A 9000 series Scat crank is a good cast crank and some have reported using it in 500+HP applications, but it's not going to be as strong as a forged unit. The cheap rods will most likely fail at some point far south of the RPM's that your cam will need to run at for serious HP output. Rods and rod bolts are the weak link in most high RPM applications. I would spend more on the rods and get good ARP rod bolts for them. I would also run a forged piston too.
There's my .02 cents.
Mark
[Modified by 81vette, 11:05 AM 9/13/2003]
A lot depends on what RPM you plan on turning in this engine. If you are just wanting to use existing parts no matter what, and you can keep it below 5500 RPM you might be OK, but with that big cam and heads your going to be leaving a lot of HP on the table running it below 5500 RPM. If this is the situation you might consider at least upgrading to some good ARP rod bolts.
If you plan on running the engine RPM to the cam and heads potential, then the 2-bolt block would be OK if it's properly machined, has good wall thickness, and uses ARP bolts for the caps. A 9000 series Scat crank is a good cast crank and some have reported using it in 500+HP applications, but it's not going to be as strong as a forged unit. The cheap rods will most likely fail at some point far south of the RPM's that your cam will need to run at for serious HP output. Rods and rod bolts are the weak link in most high RPM applications. I would spend more on the rods and get good ARP rod bolts for them. I would also run a forged piston too.
There's my .02 cents.
Mark
[Modified by 81vette, 11:05 AM 9/13/2003]
Instructor
Joined: Sep 2001
Posts: 209
Likes: 0
From: Seattle WA
Re: Will it live? (81vette)
This question comes up rather often and more info can probably be found by searching. I have been running a sbc 400 for 2 years with stock rods/crank 2 bolt main with standard main bolts. I rev to 6000 when racing and it has not failed (in that way at least). Of course I usually put around at under 2500 rpms in normal conditions. Just make sure its well machined, balanced and assembled. :cheers:
Race Director
Joined: Oct 2000
Posts: 14,994
Likes: 79
From: central FL, near the beach.
Re: Will it live? (belair55)
since it is just to play around with for a couple of years,
YES
it sure should last.
if the parts are good, assembled right, and used with a rev-limiter :cool:
YES
it sure should last.
if the parts are good, assembled right, and used with a rev-limiter :cool:
