The Stovebolt Site Forums The Shop Area The Electrical Bay Gauge question

I would like to install a Ls 6.0l in my 53 3100. The question I have is what is the oil pressure range on a Ls? I love the look of the old gauges but don want to peg it out and damage the gauge. Thanks Jay

Way too high for a Chevy gauge, almost too much for the GMC 60 PSI gauge. With a little creative tinkering you could fabricate a bypass setup where the gauge only gets partial pressure, essentially turning the gauge into a glorified idiot light.
Jerry

What is the minimum acceptable oil pressure for an LS?
I don't believe that you will damage the original gauge with excess oil pressure.
You could use the original oil gauge as an idiot light. If it isn't pegged, you have an oil pressure problem.
Carl

I had the same problem when I put the V8 in my 37. A gent over in Greeville S.C. does rebuild on gauges. He recalibrated my gauge so that 15 is 30 or 30 is 60...essentially fixing it so that the actual pressure is double the reading....but it still pegs the 60lb and has for 15 years and still no gauge problems so don't worry about it being pegged!

I had the same issue in my 49 Suburban when I put a 350 in it. It pegged when cold until it warmed up and was pegged a lot of the time even when warmed up. 15 years and I never had a problem. I had also installed an aftermarket gauge so I could watch the actual pressure.

I think Jerry may be on the right path toward a solution. All pressure sensors are not created equal just like gas tank senders. They do operate the same way by varying the resistance across them to change the amount of current going through the gauge. Well, the one addressed here.
If one were to change sensors to one having a lower change in resistance per pound of pressure then you could use your old gauge without it pegging. Of course the number on the gauge face would no longer be correct. Do remember that these senders don't have good resistance to pressure curves. The engineers design the sender/gauge to operate in the most linear portion of the curve. That means if you operate outside the linear portion, all bets are off.

There is no resistance involved in an oil pressure activated oil gauge.

Just buy a repop 0-60 psi GMC gauge and don't worry about it.

Jay,

Before I restored my '36 Chevy PU in the 1970s I ran it for 5 years and about 50K miles as a daily driven sbc powered "rat rod". The original oil gauge was always pegged by the sbc. Now 40+ years after being restored back to original, including the 207 engine, that old oil gauge is still doing just fine.

Everybody that is using a mixed and matched gauge/sender that says everything is fine just means their motor never blew up. They don't know what oil pressure they have. "pegged" is not a number. Use a LS 6.0 compatible sender (electric) and gauge. Reface gauge for "orig look" or stick it under dash. I don't know if your oil pressure goes thru a computer or not. If you want a tubing style (mechanical), I'm sure you can adapt for that style gauge.
I searched O'Reilly's under 2006 2500 6.0 and they show Electrical and Mechanical gauges but only electrical sender/switch ?????? All are 0-100

Thanks to all. I hate to run a electric but since my 49 is going to be original the 53 is going to be more of a sport truck I might as well run some Dakota gauges. Since it's going to be bagged I want accurate info.

Just to make sure my career in instrumentation and process control had not totally left me, I checked. Perhaps some of us should do the same. Just Google 'electric oil pressure sender operation'.
I have also never seen an unaltered LS motor with a Bourdon tube oil sender but tomorrow may prove me wrong.

I was referring to creating a calibrated bleed upstream of the Bourdon tube original gauge to return a portion of the oil to the crankcase- - - -maybe with a needle valve adjustment to allow almost- - - -but not quite full-scale deflection of the gauge with the engine cold. A very small calibrated leak back to the crankcase would not affect oil flow to the bearings adversely, particularly if a 1/8" OD tube was used to supply the gauge and plumb the bypass.

An idiot light would be just as useful, so using the OEM 30 PSI gauge with a calibrated leak would serve the same purpose- - - -"Yes, you've got some oil pressure- - - -who cares how much it really is?". Now, would someone please explain WHY oil pressure builds up in the first place- - - - -for the self-appointed "experts" who think a specific amount of pressure is necessary?
Jerry

What is the subject here boys? This person can use an electric or mechanical gauge in the same hole in the block. These would have a high number gauge, like 100. Either way will give the oil pressure of the motor if that is what you want.

Jerry has a suggestion to allow a stock gauge to be used by shunting the pressure. As far as how much and who cares, you just need to know and see it climb and fall. You can use a cardboard face on your gauge that has Mickey Mouse on it but you need some sort of calibration reading or scale of any kind. But some folks want to know the actual pressure. Pegging is not Kosher in my book. It will not detect a problem. If it does not detect a high pressure problem, you don't need a gauge. What do some of us "need to check"? Please advise.
A mechanical oil pressure gauge does not know what motor or vehicle it is in. It just tells pressure. You can use one if you don't want to rely on electric. An "electric" one is actually electro-mechanical.

A bearing that is receiving one drop of oil from the lubricating system for every drop that leaks away will be properly lubricated- - - - -at ZERO oil pressure. The fact that pressure rises at all indicates the bearing(s) are getting more oil than is needed. As long as every place in the engine that needs it gets an appropriate amount of oil, it really doesn't matter if there's 5 pounds of oil pressure or 50. The only real hazard is a situation where some bearings near the end of the oil circuit might be starved for lubrication due to excessive clearance and leakage past the bearings while ones nearer the oil pump get lubed. Having just a few pounds of pressure, measured near the end of the lube circuit, is plenty. Most idiot light turn on at or near 7 PSI.

One danger is developing enough oil pressure to damage the pump drive components, such as twisting the tang off the end of the distributor shaft. I've seen that happen when a pump relief valve gets jammed in the closed position. I've also seen an engine with so much oil pressure that the engine wouldn't idle- - - -stalled by the load of driving the oil pump.
Jerry