Oil pressure

[corporatewhites]

Can anybody advise me on oil pressure at tickover for the 5.7 chevy American speed engine (400 bhp). After owning the car for 2 months with the carb badly set (kept stalling so adjusted the tickover) had the factory set everything up and now running great. My only concern is that I was out yesterday on a 40 mile run and got stuck in traffic temperature was 90c and pressure was 1/2 Bar at tickover but once pulled away was between 3 and 4 bar. When started this morning was 5 bar when cold and seems OK. The car is standared factory spec and has covered 2000 miles since build (2002).

[martinlaw]

Hi,

My Sport when warm has around 40psi at idle and increases to 65psi at about 4000rpm.

Sorry guage does not display bar readings.

Hope this helps.

[steve_d]

.5 bar = 7.25PSI
40PSI = 2.76bar
65PSI = 4.48bar

Steve

[corporatewhites]

Thanks for the info guys,I think it best to talk to the factory as it would appear to be low at tickover. I will let you know what they say.

[scuff]

I'm Guessing that you may have already checked your oil level, but also check that the dip stick is sealing and seated properly. Easy to see, depending where your dip stick is. I had some splashes of oil on the exhaust header as a result of the dipstick not being put back correctly. Additionally the oil was just below the lower limit. When topped up and the dip stick put back the oil pressure came up to just over 2 bar on tick over

Edited by scuff on Thursday 3rd August 12:23

[corporatewhites]

Checked oil level and dipstick and all OK. Thought I would go out for a run this evening to see if it would be the same. The first hour never went below 1.5 Bar at tickover then 5 minutes from home pulled up to a junction oil light flicked on for a split second and the reading was 0.5 Bar. I think I am going to call the factory before any real damage is done.

[davrianman]

Had a very similar problem on both my Cerbera and my race Davrian. It was a broken spring on the oil pressure relief valve. If you can access it (I'm not sure of the location on a SBC) then you can tell by pressing on the piston and seeing if you have any spring resistance.

Just a thought if you haven't checked it yet,

Cheers!

[gtr-gaz]

I had a similar problem with mine last year. Engine builder could not find a lot wrong with it, he thought it must have been the pressure relief valve.

Just a thought, but the dipsticks supplied by AS do not always correspond to the correct oil level! I was told by AS to put 7 qts (US) in the engine and mark the dipstick to suit. An oil change should need 8 qts with filter, but does not include accusump. It might be worth just draining the oil out to see how much you have in there.

[Builder]

I have a vehicle with an SBC. It's not an A/S engine. In PSI:

Cold -
40 idle
60 driving

Hot -
20 idle
45 driving

I don't think it's too uncommon to see slightly lower numbers, in some applications. Anything under 10 PSI at tick-over would be a concern. However, it would be best to get a direct comparison to an A/S setup.

Is it possible that the sender or instrument is defective?

[yiihaa]

Do you know what oil it has in? AS told me to use quite a thick oil, 20W50 and specifically said not to use a synthetic oil. If someone has used Mobil 1 0W30, that would explain the low hot pressure.

I use this:
Valvoline oil

[corporatewhites]

Yes the car has Valvoline oil,my only thought was the oil has not needed any top up in 1000 miles since purchased. I'm sure I have seen in earlier topics that the AS engine does use a bit of oil but not this one,is this possible ?
Decided to stick a pint of oil in (shows just over full on dipstick) and now sits at 1 Bar so a little better. Going to the Factory open day so maybe one of you guys could take a look and discuss with the factory.

Hope to see you in the morning.
Steve

[corporatewhites]

After speaking with Richard today at the factory open day he suspects the oil sender has some crud blocking it as the engine runs perfectly Ok with no funny noises.
He came straight to me when I arrived this morning (factory open day) and suggested I pop the car in next week just to check over whilst I wait,how about that for service.