turbrorx7

Recently installed the Dewitts radiator with drivers side EOC, 7psi bypass hardlines, and dual SPALs and I'm seeing a 10psi drop across all RPMs. Before the install I was getting 40psi at idle and 65psi at sustained WOT. Now I'm seeing 30psi at idle and a max of 55psi at sustained WOT. I installed the 7psi modified C6 hardline kit for this reason, but somewhat annoyed/concerned. I expected a loss concidering the size of the engine oil cooler, but I was thinking maybe 5psi would be the number. Thoughts?

BTW, can't complain at all about temps with this setup.

aaronc7

Stock oil pump?

blkbrd69

I noted a 5 psi pressure rise when I replaced the stock C6Z hard lines with larger oil lines, also a 7 psi rise when running just the bypass instead of the C6Z bypass setup.

My data on my lines showed they were quite restrictive.

aaronc7

I added the same radiator/EOC setup as the OP and I honestly didn't notice much of a pressure drop at all. Definitely not at idle, I'd expect some at WOT/high rpm, but no more than 10psi. I am running a Melling "standard volume, high pressure" oil pump. I got the high pressure spring model as I figured it would help offset the pressure loss associated with running an oil cooler.

turbrorx7

Running stock pump, no other engine mods. Still, I'm surprised, I have the Dewitts/LPE 10an line kit sitting in my garage and chose not to go with that setup because of the integrated EOC pressure drop and now I'm questioning the move

I had healthy oil press before so I don't see as that the issue. Just looking to hear the experience of others.

blkbrd69

https://www.corvetteforum.com/forums...iscussion.html

turbrorx7

Not sure if this is regarding the 10an lines? The line flow rate isnt the issue, the restriction is said to be a result of the size of the EOC and its maximum flow rate, so using either the hardlines or 10an lines would cause a pressure drop. With the hardlines however, the EOC is bypassed with anything more than a 7psi drop. Maybe the bypass mechanism isn't working?

Soloontario

Never had 40 PSI at idle before or after adding the oil cooler. Using 5W-30 oil. Didn't notice any drop in pressure after the addition of the cooler (Dewitt's in the rad tank kind)

turbrorx7

What kind of plumbing are you using for the oil cooler?

Soloontario

Sorry, I don't know, it came with the DeWitt's rad kit.

Looks pretty substantial.

ZedO6

The DeWitt's supplied hard lines are a GM part from the C6 and due to the bypass in that part, you should not see a significant drop in oil pressure. CHANGING THIS to a non bypass setup like the LPE into the DeWitts EOC is absolutely going to show a pressure drop and a bad idea. You need to use the bypass line which at most should drop the OP 6 PSI. This is going from notes I got from DeWitts.

turbrorx7

Which is why I installed the GM modified hardlines, yet I'm still seeing a 10psi drop.

turbrorx7

Is are they hardlines (like AC lines) or soft/flexible stainless steel lines?

Soloontario

Flex lines

Joshboody

I have stand alone with 10an (no bypass), stock ls1 and didn't notice a drop. Could be one but definitely not 10psi. My cooler is little larger than LPE one.

fatbillybob

I'm more concerned with low startup oil pressure. When my car has sit for weeks I get low oil pressure warning upon startup. How do you solve that? Starting car and immediate shut off a couple times seems to get the pressure up. But it seems to me that at idle you are at 1000rpm and if you use the 10psi per 1000 rpm then you are probably ok on startup. The oil pressure sensor triggers around 20psi right?

ZedO6

Carl I have the same issue with my C5Z and DRM oil cooler. Just pull the fuel pump fuse and crank the engine 15 seconds on, wait 15 seconds, repeat until you get oil pressure. Ideally you put in a fuel pump switch but I never got around to it.

turbrorx7

The issue comes from the small size of the internal oil coolers on the radiator, they don't flow at a high rate. You shouldn't have the pressure drop problem on standalone coolers.

Dan H.

What is LPE?

ZedO6

Lingenfelter Performance Engineering