Quick one about engine oil for 440

[Goblinking]

Whats everyone's opinion on engine oil for a healthy,built 440,with a solid roller roller cam?I need to change the oil and don't have a clue what is best for the old beast.
It has around 80 psi at idle,but i've read that is not Necessarily a good thing.

[Pete]

As you have a roller cam you can run pretty much any good quality oil and you will not need to run any ZDDP additives.

80psi sounds high, assuming the engine is fully run in.
More importantly, what is the oil pressure at high revs?

Too much pressure can put a high load and stress on the Oil pump drive shaft and they have been known to fail at higher rpm.

[Goblinking]

Sorry Pete,i made a mistake in the first post.It has a solid flat tappet cam,roller rockers

[Blue]

10/30 Lucas hot rod oil for me, has enough zinc in it for flat tappet cams. If you really have 80 psi at idle you need to sort that out before you burst the oil filter. 20 psi at hot idle is enough and 10 psi per thousand RPM after that. Milodon make an adjustable pressure regulator for big block oil pumps so you can dial in the pressure you need.

[Goblinking]

well Blue,that's quite concerning.It will blow the oil filter apart!
I read somewhere about changing a spring in the oil pump or cutting a few coils off it?

[SJH]

Have you checked the oil pressure reading with another guage/sender to make sure this is not the problem ?

[Blue]

well Blue,that's quite concerning.It will blow the oil filter apart!
I read somewhere about changing a spring in the oil pump or cutting a few coils off it?

I've blown a filter apart with over 100psi when the engine was cold. I usually cut 2 coils off the stock spring to get the pressure down to sensible levels, it's easy with the external pump on a big block, not so much fun on a small block...

[Goblinking]

Well i've bought Valvoline vr1 racing 20w-50,hopefully i'll change the oil tomorrow,see if it makes any difference with the oil pressure.

[Goblinking]

New filter and oil and the pressure is down to 70 psi hot,goes to 80 when revved up.That 20w-50 is thick stuff though.

[Dave999]

it is

and the pressure rises as the filter gets clogged, to a point, then the filter just bypasses the filtering element, and loads of gunk goes through the bearings

if the motor was built for race use it would have clearnces on the mains built in, which would be at the "nearly too much end" of the clearnce tollerance stated in the manual i'd expect 2.5 thou for a 2.5 inch journal

if the motor was built as per manual then they may be much tighter

for exmaple mine is built with 1.5 thou clearance on the mains
1) oil pump is rubbish even when new
2) the spec in the book clearance for the main beraings as 0.0005 to 0.0015 inches half a thou to 1 and half for my 2.5 inch main jorunals (7 of them)

the rule of thumb for a race motor would be 1 thou per inch of journal, you will see this quoted a lot

i.e 0.0025 clerance which according to the factory manaul for my motor is completely unnaceptible,
causing low oil presure at the big ends and lifters.
i had problems with a regrind "its gonna be given some beans init" .... 2.5 thou no no no no no, read this thats why its printed out for you... said me

the other thing that has an impact is the clerance at the sides of the bearing. if the crank is standard and not reground the journals have a small radius cut at each side, this controles oil escape from the bearing and provides some In-built weakness (not desirable in a race motor) to the crank. if a crank snaps it doesn't snap in the middle of a journal..... it snaps at the side so this under cut radius is sometimes not done

if the crank is reground and these areas where not replicated then the width of the bearing has much more impact
if the crank was aftermarket and didn't have these areas for added strength... the same applies
i.e some time checking clerances at the sides of the bearings is supposed to be done, and the fix is usually to take a smidge off the side of the bearing (obviosuly not the thrust beraing) but the rest to get that clerance in spec as well.

if yours has been built to factory spec low end of tollerances and has a reground or aftermarket crank, with bearings a smidge wider than desirable hence with minimal side clearance at the mains and the big ends, it might explain your really quite high oil pressure.

you might need to coinsider a lighter oil 10w30 etc it will still be a fine motor, do not worry, you just don't need the thick green gloop some of us run.

dave

[Goblinking]

Hello Dave,the engine was built by a neighbour of big daddy don garlits,who actually helped him with the build,so it makes about 550hp,everythings forged etc and it only has about 400 miles on it.I finally got to drive it up to temp the other day and it drops to 40 psi when hot,then when you give it the gas it goes back up to 80 ish psi.
I'm fighting the urge to put the engine in my challenger,i've never had a big block before and its grown on me straight away.

[Dave999]

Ahhhhhhhhhhh i think you will be alright

do you still have a rleationship with these two chaps? it might be worth asking what they would put in.....


Dave

[Goblinking]

Sadly i don't know either of them,the bloke i bought the truck from,bought it from him,and has owned it and showed it at events for the last 10 years,and he has had it down the strip a few times,but he emailed last night to finally reply to my question of what oil it had in it and would you believe it,it was valvoline vr1 20w-50.

[Dave999]

ahahaha and back to where we are.... Nice.