DunnoWhoThisIs

iTrader: (9)

After installing heads, lifters, pushrods, and a cam my oil pressure really has went to ****.. on first start up its fine, acts normal, idles around 60psi, then for a while driving it it stays normal idles at about 40psi then while driving goes up to around 60psi, the more i keep driving it the lower the psi goes, i was running 5w30 mobil 1 sythetic and it would go all the way down to 20psi idling, then around 40psi driving, now i have 10w30 Castrol Syntec in it and it stays at 40psi unless i get on it hard and it goes up to about 50psi or so.. whats the deal here? any ideas?? someone told me that a guy around here had a ls1 and after a cam install it ate a cam bearing and oil pressure did something like it.. i hope thats not what is going on.. any ideas are appreciated!!!

KingSumthn

iTrader: (4)

i had a similar problem after my first cam install. idled around 20 and driving was 40 at most. i just left it like that for about a year and a half until i did my next cam swap. i changed out my oil pump to a ported ls6 from texas speed and ever since my oil pressure has been amazing. i guess my stock ls1 pump was just getting old and worn out and couldnt handle the bigger cam.

tylerdj

iTrader: (31)

Did you change the oil pump when you did the cam swap? Have you noticed any oil leaks anywhere on the motor?

Oso Vega

iTrader: (4)

Did you forget to put the o-ring on the oil pump when/if you changed it?

Bill Bowling

iTrader: (6)

If he forgot the o-ring his pressure would be very low or nothing.

Bill

purdueranger

iTrader: (11)

OP, when oil gets hot it thins out and you will see an oil pressure loss. Going from 5-30 M1 to 10-30 Catrol is really going from 5-20 to 10-30. You are actually running a thicker oil now.

cold start ups you will always have the 40-60psi at idle and then when it warms up 20 at idle to 40 psi while cruising is fine.


rule of thumb I have always hear is you need 5psi of oil pressure for every 1000rpms your engine is running.

purdueranger

iTrader: (11)

most likely the guy knicked a cam bearing and lost oil pressure. if that is the case then you should always see a low oil pressure from the get go. same thing goes for a spun bearing.


one test you could do is run the engine for a little bit and then take off the valve covers to see if you have oil in the overhead and if you do then your engine is getting the needed oil pressure to lubricate the pushrods, rockers, and springs.

excessive crankcase pressure will also prevent oil from draining back down into the pan which would cause an oil pressure drop. (doubt this is going on, see it more often in diesel applications)

DunnoWhoThisIs

iTrader: (9)

awesome info guys.. that really helps me out alot.. i was getting real worried about bearings there for a little bit.. it is a 99 and ive heard problems out of the 99 oil pumps in these things.. guess ill have to go to a ls6 ported and while im at it get a timing chain.. it is the factory pump for who asked if i changed it.. i didnt.. i didnt even touch the pump while doing the install.. thanks much guys!!!!

white99

iTrader: (13)

I went with a Melling oil pump. They're great pumps for these motors and much better than the LS6 ported. Others will tell you the same

blkbird

iTrader: (28)

I have the same issues but now even after i swapped out with a melling high pressure pump i still get about 12-20psi at idle and about 50ish at WOT with a hot engine. Just gonna run it till it breaks. Good excuse for a possible 402.....

white99

iTrader: (13)

blkbird, the melling pump comes with two springs depending on the model. The red spring is for lower pressure and the blue is for higher pressure. Some models only came with one. Mine has two

blkbird

iTrader: (28)

I just got the m295 with the one spring. Its supposed to be higher pressure and not volume. Didnt open it up to see what color the spring was. doh!!

DunnoWhoThisIs

iTrader: (9)

well hopfully its a oil pump and not a bearing somewhere.. i would really like to put that money towards something else if you know what i mean.. i really need to get me a rearend and suspension that will handle the mods i have.. the oil pressure really started going down about a month after all the installs... but it stays constant.. dunno what the deal is really.. thanks for the inputs!! keep em coming!!