355 low oil pressure at idle?

[ericmeier]

I just got a 355 going since doing a cam swap. It has good oil pressure when its cold at idle but when its warmed up it drops to almost nothing.at highway speed its fine. It has conventional 10 30 and a gram filter didn't know if I change to something different if that would help. Its I'm my 72 kingswood wagon

 

[lilbowtie]

Try an AC those frams are restrictive.

 

[Doober]

Fram = blech... their internal construction isn't worth it for a performance engine. All I use now is Wix, though Purolator is boasting metal internals for their filters in their new ads too.

 

[ericmeier]

I thought that's what I would hear I will change it and go from their. Thanks

 

[Doober]

Even if it's a little low I wouldn't worry too much, just a little more bearing clearance probably. My 383 with a brand new crank, bearings, etc. idles about 10-15psi hot at around 600-750rpm. By 1200rpm it's up to about 35-40psi. I measured bearing clearance at .002"-.0025" across all the mains, I think the rods were around .0015".

 

[81rustabu]

x2 on changing the fram to a good wix filter. Fram are the worst filter out there.

 

[Ed Cannon]

sbc can idle at low oil pressure, as long as the pressure goes up with rpm your ok.

 

[DOUG213XRJ]

I also had a SBC with low oil pressure at idle when warm, I also changed from Fram to NAPA gold oil filter It didnt help. I did a engine swap and that same motor had great oil pressure, Mine turned out to be the oil pressure gauge. So I would try a different oil pressure gauge. Ill stay with the NAPA gold oil filter though.



Doug

 

[Doober]

One of my best friends had an '85 K10 longbed... nice truck after he restored it... had a 355 he & his dad built when we were in high school, don't know cam, heads, etc. but he always babied it. Even after the rebuild it didn't show more than 10psi at 600-700 but was fine above that.