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Author Topic:   How long will this survive?
posted January 22, 2004 05:23 PM
thats pretty much what we run but with a 350 and my buddy has had up to 35 nites on it before a refresh myself i run 20 but as long as you don't rev the heck out of it and keep up maintence and don't let it get hot she should last for ever

posted January 22, 2004 07:02 PM
i had a similar motor go 45 nights before i sold it...shoulda never let it go!!


posted January 22, 2004 08:47 PM

posted January 23, 2004 07:12 AM
A 377 with performance bearings and ARP bolts should live a long happy life under 6500. 2 seasons wouldn't surprise me before any noticable wear on the bearings or cylinders started. Much over 6500 and stock crank & rods get marginal in a hurry.

The lighter the piston, the longer the rods and rod bearings will live. You are having it balanced right?

posted January 23, 2004 11:49 AM
we ran our stock rod,crank 350 for 40+ nites turning 7200-7500 rpm.It had arp rod bolts,x rods,heith black hyperteck pistons.

to give ya more of an idea,we ran 462 double hump,2.02 valves,cam wise we running around a .570 lift cam.Most guys run from a .530-.570. Most all of us are turning this type of motor 7000-8000.
We have to keep stock type of intake,but can run any carb exept a preditor,and no alky.
we all run 750 double pumpers.

I think it would last,good balance is the key.

posted January 26, 2004 07:41 AM
You should be fine up to about 7-7200 for 30-35 nights of half-mile racing. I get excellent life out of my 350 crank motors like that. I have more trouble breaking the pistons than any other problem. I pull them out of my 383's at 10 nights and toss them and I found out this year that at about 35 nights, I should do the same with my 350's.


posted January 26, 2004 02:43 PM
10 nights and throw pistons away??

Those must be some pretty cheap pistons or you're really wringing the thing's neck. I'd go broke throwing pistons away 3-4 times a year!!

I have a set of KB231 (5.7" rod 350 LW) pistons that have been in 3 different blocks. They've been overheated, detonated (bad gas burnt 1 piston in the 1st motor) and run in the 6000-6500 range the whole time. I plan on putting them in another block (the 1 this year developed pin holes in #8) for a backup motor.

posted January 26, 2004 10:43 PM
if your turning a stock rodded motor 8000! your tach is reading for a 6cyl. move the button one spot right to 8cyl.

posted January 27, 2004 04:27 PM
It will last as long as the weakest part of the engine doesn't break. This is true with every motor. Should last all season, but.............

posted January 27, 2004 06:19 PM
Eric,here in OKC,the 3 or 4 tracks that carry same rules say we most run stock rods,cranks.I turn mine 7,500,got 40+ nites on it.Iv hot laped a buddies car and turned 8,000 with it,asked him and he has been twisting that all year.Iv lost 3 motors in 5 years on runnin,2 broken pistons,and had a rod bolt brake,after that motor(1st motor we lost) we started having new rod bolts put in and reconditioned and never had a big problem.

Most everybody is having the cranks knife-edged and getting them as light as possible.
7,000 isnt that big of a deal i dont think,just make sure its assambled right,and good machine work.

Wind Walker
posted January 30, 2004 07:22 PM
The most important thing with that set-up (like any set-up), is proper assembly. In other words, do it right the first time!

Other than a part failure, it should do well. Someone posted above about running "X" amount of races without ever changing the oil......$25 worth of service every other week, is a lot cheaper than $2500.00 later down the road!

Have a great day,

Wind Walker

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