Hey guys lookin for some imput, I know i can get a stock length 5.565 rod from eagle in a 4340 h beam, my motor already has a 10.25>1 Forged pistion in it with stock rods and crank. everyone says go 5.7 or 6.0 rod, but what if i bought the 5.565 rods and better crank, and used my good forged pistons i have. this is for a street car thats gonna see nitrous, so im iguring the thicker piston for the 5.565 rod is gonna be stronger for the n20 anyhway so it should be a win win, stronger + cost me less money as i dont have to by a set of pistons. Im put please 🙂
short rod 406 imput
- Thread starter junkygbody
- Start date
- Status
the problem with shorter rods is that they angle more at mid-stroke. this pushes the piston sideways into the wall.
if you already have pistons, then you're kinda stuck with the stock rods. if there is an inherent problem with breaking rods on the 400, get good ones. otherwise 5140 forged rods are cheap and very strong.
if you already have pistons, then you're kinda stuck with the stock rods. if there is an inherent problem with breaking rods on the 400, get good ones. otherwise 5140 forged rods are cheap and very strong.
Just build for low end torque, not high RPM HP and you should be fine. I have never had a short rod 400, so I do not speak from experience, but Megalodon 6 is right with regards to theory.
what do you guys think i could rev that type of motor to, im going to 6K on the stock rods with arp bolts in them right now and havnt had any problems
to take any SBC over 6k takes money, plain and simple. good rods. crank, pistons, springs etc. i don't know how much of a problem piston rock would be at high RPM's though. but unless you're gonna be doing hard core racing, you don't really need to go over 6k
The conventional wisdom on a short rod 400 is that you can run 5500rpm. Given that, you need to figure out how to maximize your torque band and gear the car to run in that range. A 3.08 or 3.23 gear would be the max you would need. Expect to minimally make 450-500 ft/lbs and 350-400 hp. A cam with a wide LSA, high flow dual plane and heads that run optimally at mid range RPM's will make it a fun car that will be reliable as well. I think engines like that are more fun to drive than something like an S2000 or RX-7 that makes no torque and revs to 10,000 rpm.
well i spin the car to 6k w no problems with stock rods and crank with arp rod bolts. Im thinking around 7,000 with and eagle crank and eagle 5.565 rods should live just fine.
I spin mine to 6000(limiter set at 6400). The crank, rods, and pistons are stock. The only issues I have is with breaking pistons. That might have something to do with boost on stock cast pistons though. 
:lol:
:lol:- Status
Similar threads
