Max Safe RPM on a Stock Motor?

[bordin34]

I am wondering what the maximum safe rpm would be for a nearly stock 400. I am pretty sure the rotating assembly, heads, and valve springs are totally stock. I am asking this because I have my rev limiter set at 5500, about 70mph in 1st gear, and occasionally hit it because the motor is still making decent power up there. I have heard that 5000 is about the max for the stock oiling system. Can anybody help me out?

[Rayzor]

My opinion is 5500 is pushing the issue for the stock rod bolts and the valve springs. while it still may be pulling some up that high you may be faster to shift sooner like around 4800  so your next gear will hit the begining of your torque curve.

[flyinlow]

Safe RPM?  500 under where it went boom   

Depends on alot of things;  Miles, maintenance since new, are all 8 firing equally well ,was it built on a Monday?
,
Original Redlines where around 5500 rpm. Conservative, to get the car thru warrenty. I worked a Plymouth dealership for a couple years in the 70's . Never saw a 400/440 blow the bottom end out. The few  problems that happened where caused by the valvetrain breaking at high rpms then wiping out the pistons.

Long term I would think that everytime you go over 5000 rpm you are shortening the engine life some. However,I have taken 100,000 + mile 440's up to 5500 rpm lots of times. No broken rods screwed to my garage wall.   

[bordin34]

Well I go to 5000rpm at least two or three times everytime I drive it. Maybe I will lower the limiter to 5000 to keep it safer.

[Cooter]

My brother always told me to wind it till the crank turns backwards or the pistons swap holes and bang second....

[Musicman]

You can only do so much with stock springs and hyd lifters... better safe than sorry.... It isn't doing all that much at 5000 anyway if it's stock.

[x340kid]

 :fireangry:hi new here my understanding is this  hold her til she blows then holdher a little longer ..JUST IN CASE!!!

[mauve66]

stock hydraulic lifters will probably start to float around 5500 anyway