New to me Barracuda with Mopar Crate 390hp low oil pressure

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If you add a bigger alternator make sure the wiring is upgraded to handle it. You can't put 160 amps through the factory bulkhead and amp meter. The factory wire on my dart is only 10 gauge.
 
Hot idle oil pressure of 20-25 is where mine runs on a mech gauge before and after a rebuild.
 
Im not using a filter adaptor. Later on I want to do an oil filter relocation.

It had a short Fram filter in the stock location. I used a short Purolator premium filter.
Never did care for Fram, pretty scary I you cut one apart.
Puralator work well.
 
Mechanical gauge installed. 65 degrees outside. Startup idle 65psi. After two cycles of the electric fan kicking in and off the hot idle psi was about 18-20. In gear with lower idle around 860rpm (guessing) The psi was 16-17psi.

1- proves the electric oil psi gauge didn’t like the low volt issue.
2- still kinda of low according to many comments on a warm engine idle that should be a low mile engine. The prior owner said he changed to bigger cam, roller rockers, and had head work done on the crate 360/390hp.

I checked the oil filter temp surface with laser temp gun. It was 205.

Should I bother with a cylinder leak down test? Cold cranking psi was good.
 
Mechanical gauge installed. 65 degrees outside. Startup idle 65psi. After two cycles of the electric fan kicking in and off the hot idle psi was about 18-20. In gear with lower idle around 860rpm (guessing) The psi was 16-17psi.

1- proves the electric oil psi gauge didn’t like the low volt issue.
2- still kinda of low according to many comments on a warm engine idle that should be a low mile engine. The prior owner said he changed to bigger cam, roller rockers, and had head work done on the crate 360/390hp.

I checked the oil filter temp surface with laser temp gun. It was 205.

Should I bother with a cylinder leak down test? Cold cranking psi was good.
I understand your concerns.
In reality all the hot oil pressure your engine needs to survive is 10 psi per 1000 rpm.
My guess would be that the rollers are consuming some of the low rpm volume which may be knocking down your hot idle pressure
 
I understand your concerns.
In reality all the hot oil pressure your engine needs to survive is 10 psi per 1000 rpm.
My guess would be that the rollers are consuming some of the low rpm volume which may be knocking down your hot idle pressure

That makes sense. Comparing the roller rockers and roller cam to modern engines; those guys often report 10-15psi at hot idle.

Prior owner spent money on parts; so I don’t doubt he got the best or largest flowing pushrods, rockers arms. Just worried me about proper installation Of those parts.

I don’t know if he did the engine work or not. Lack of kickdown cable. Using standard amp alternator on a fuel injection, electric fan and car speaker amp. Blue rtv to seal up pcv, breather grommet, and valve cover plug grommet. Looks like someone even hand cut a small gasket for the oil pressure sending unit and then smeared blue rtv on it.
 
That makes sense. Comparing the roller rockers and roller cam to modern engines; those guys often report 10-15psi at hot idle.

Prior owner spent money on parts; so I don’t doubt he got the best or largest flowing pushrods, rockers arms. Just worried me about proper installation Of those parts.

I don’t know if he did the engine work or not. Lack of kickdown cable. Using standard amp alternator on a fuel injection, electric fan and car speaker amp. Blue rtv to seal up pcv, breather grommet, and valve cover plug grommet. Looks like someone even hand cut a small gasket for the oil pressure sending unit and then smeared blue rtv on it.
All of that sounds like a back yard mechanic.
You got 2 choices
You can fix what you got, the way you like it.
Or you can sell it and build one they way you like it
 
All of that sounds like a back yard mechanic.
You got 2 choices
You can fix what you got, the way you like it.
Or you can sell it and build one they way you like it

Doing both. Fixing what needs fixed to enjoy the car and if I get offered a good price I will sell it. This is my first Barracuda, I actually wanted a Dart. The wife liked the Barracuda looks better and now so do I. I really think I want a manual transmission.

The 10 year discontinued Mopar fuel injection kit is a headache. Idle air control valve isn't a mopar part. After much research, it is a Holley thottle body which uses a holley IAC valve or a GM LS1 IAC. To further mix it up; the IAC parameter in the ECM need to be reset which I think happens once the ECM reads 40mph (thats what GM computers do. But the hodgepodge Cable to 90 degree adaptor into the electric conversion that also has an adaptor for the speed signal for ECM... Something in that system isn't working. IAC never adjust to learn idle position. So it is most likely staying part open even at cruise speed, which complicates tuning.

My local "custom" shop said it would just be best to remove the outdate system and go with Holley Sniper. Which I agree.
 
My local "custom" shop said it would just be best to remove the outdate system and go with Holley Sniper. Which I agree.

I only have one experience with the new Sniper.
I think it’s a great system for a hot street car.
 
Doing both. Fixing what needs fixed to enjoy the car and if I get offered a good price I will sell it. This is my first Barracuda, I actually wanted a Dart. The wife liked the Barracuda looks better and now so do I. I really think I want a manual transmission.

The 10 year discontinued Mopar fuel injection kit is a headache. Idle air control valve isn't a mopar part. After much research, it is a Holley thottle body which uses a holley IAC valve or a GM LS1 IAC. To further mix it up; the IAC parameter in the ECM need to be reset which I think happens once the ECM reads 40mph (thats what GM computers do. But the hodgepodge Cable to 90 degree adaptor into the electric conversion that also has an adaptor for the speed signal for ECM... Something in that system isn't working. IAC never adjust to learn idle position. So it is most likely staying part open even at cruise speed, which complicates tuning.

My local "custom" shop said it would just be best to remove the outdate system and go with Holley Sniper. Which I agree.
I get first dibb's on the car.
If you are going to flip the car put a carb on it and be done.
Pic's would be nice
 
No factory service manual that I know of gives an idle spec for oil pressure. It's usually 2000 RPM. What is the oil pressure at 2K?
 
My guess would be that the rollers are consuming some of the low rpm volume which may be knocking down your hot idle pressure
Just saw this. I am doubtful. There are several restrictions in the system before you ever get to the rockers that control the flow, and these restrictions do not change with the rocker type. Now, if grooved cam bearings were used, then that changes the oil flow game up at the rocker area.
 
Just saw this. I am doubtful. There are several restrictions in the system before you ever get to the rockers that control the flow, and these restrictions do not change with the rocker type. Now, if grooved cam bearings were used, then that changes the oil flow game up at the rocker area.
I should have said - roller lifters - I agree roller rockers would make no difference.
 
Just saw this. I am doubtful. There are several restrictions in the system before you ever get to the rockers that control the flow, and these restrictions do not change with the rocker type. Now, if grooved cam bearings were used, then that changes the oil flow game up at the rocker area.

I dont agree , roller rockers w/ needle bearings aren`t going to have/give as good of pressure as arms w/ bushings.
 
The 360 crate 390hp came with Hydraulic Roller Camshaft - 288°/292° duration, 0.501"/0.513" lift. Prior owner said he had a larger cam put in. He mentioned .520 lift but wasn't able to tell me what brand or model. He built the engine about 10 years ago, before the car was even ready. I assume he stayed with roller cam.

I checked clearance on rocker to valve stem on passenger side. I could not get a .002 feeler gauge to slide in on any of the valves. I didn't rotate to find TDC. I just wanted a quick check. So that would be hydraulic lifters, I assume. Several pushrods felt like zero lash as I could spin them.

It does have adjustable Harland Sharp roller rockers. Unknown if he used 1.6 or 1.7 ratio. My gut guess is he thought bigger was better and used 1.7 ratio.

She sounds like a big cam. Wife and I love the sound.

The only cam I found with .520 lift is Crane 708511. Which isn't a big cam and doesn't match my idle vacuum reading.
Advertised Duration:276 int./282 exh. 0.520"/0.531" Valve Lift.
 
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Harland Sharp has this note on the LA V8
Special Notes:
* Needle bearing allow for more oil flow to the rockers.
* Oil restrictors may be necessary to maintain oil pressure.

They don't have any notes like this for the Magnum rockers.
 
I dont agree , roller rockers w/ needle bearings aren`t going to have/give as good of pressure as arms w/ bushings.
I have run roller rockers with needles (PRW) and with straight bushings (Hughes) on the same engine and had the same identical oil pressures.... 20psi hot idle and 72 psi hot running pressure. And the needle bearing rockers had an extra oil hole. To see what will happen, you need to examine the whole rocker oiling system with the restrictions that are there already, and also look at how tightly the needle cages are to the shafts and how that limits leakage out of the needle bearings.
 
Harland Sharp mentions that their needle bargains allow for more oil flow to the rockers. More flow = less pressure.
 
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