Ok cam is broken in and i changed the oil again. this time it is a oil pressure question on my 454. i have been using castrol gtx 10w-30 for the motor. i have changed the oil right after breakin of the cam. now i have about 20 miles on it. i have noticed that when cold i have about 75 psi oil pressure and when the car is fully warmed up it idles in park just a hair under 25 on my guage but idle in gear it is close to the 0 mark. the guage reads in 25 incraments, 0-25-50-75-100. when fully warmed up the pressure increses to about 40-50 when i floor it but never really goes much above that.

I had a cam lobe go flat and i did not pull the motor. i sprayed everything with brake cleaner and put a new cam in it. money is tight and needed to at least get it running. could i be using to thin of a oil? will i see a pressure increase if i go to a 10w-40 or a 20w-50? yes i reused the oil pump. what oil thickness should i run to get the pressure up about 5-10 psi at warm idle in gear?

Man o man. When mine did that I hoped it was nothing... It ended up being EVERYTHING. My cam broke in good enouogh to even visit my track. after the first pass it started knocking so long bottom end! I hope you fare better I REALLY do but it sounds all to familiar !
Milan

What oil pump and it's part number are you running?

You really ought consider running straight 30w for a bit, and add half a bottle ( or whole)of GM EOS to each oil change for a bit. If the weather alows in Texas, I like the Pennzoil 15-40 weight oil in a multiviscosity. It's "fleet" oil and not available everywhere, but WalMart sells it in 5 gal jugs.

Once you get a bunch of miles on the motor, sure 10-30. Don't let this motor idle low for ANY length of time. Oil spinning off the crank lubes your cam.

it is a factory replacement pump. it is a old electric guage but i believe it is right. when it idles in gear and oil pressure drops i can't hear lifters or anything it is still smooth and quiet. so i was kinda hopeing that a oil weight could bring it up some.


what weight do you guys recomend?

Hi

Any quality 10/40 or 15/40 should be fine. If it’s really hot there go with a 20/50. When you’re changing the filter check your by-pass valve, the little round spring loaded disk on the filter adapter, and make sure it’s in good shape and seating properly. Also what’s your idle speed when in gear? It might be chugging the motor down too low in gear.

If everything checks out you may want and try a good old mechanical gauge.

Good Luck

Joe

idle speed is 600 in gear

Did you take the pump apart? I flattened a cam the pump was junk after but the bearings were OK due to blocked filter by-pass. I ended up going through the whole thing due o some other issues I found when I took it down.

I`ll bet the pump is gouged up pretty bad.

Jim

At this point change to the 15-40 or 20-50 oil (if it's real hot down there)with some EOS in the 1st oil change after the cam is broken in for some added protection.

I would also change the oil again at approx 200 &
then 500 miles in an attempt to flush out any more old cam material/metal/debries from the oiling system. This would be some cheap insurance and could help save you from a rbld later down the road.

I would also idle it up a little bit if possible to at least 700-750 rpm in gear to get the oil pressure up a little more too along with the thicker viscosity oil. I know you may idle on the high side in park but you need to get the idling in gear oil psi a little higher if you can.

If your car wants to run on/desile in park after you idle it up then try shutting it down in gear before going to park.

I have personally replaced worn cams in mild to fairly hot cars and the motors lasted not blowing up later on down the road.

Thats not to say the motors would not be partially damaged from the metal in the oil but if the car was not run for a long time with the bad cam,had frequent oil/filter changes,and you flushed the motor out real well with motor flush/clean oil just prior to the cam change that you could very well go a long time before you see any reprocusions from the bad cam or maybe not any all.

At this point your oil pressure is low at idle but your 45-50 psi hot at crusing speeds over an idle is not bad,all you need is approx 9-10 psi per 1k rpms turned to be fairly safe so again,idle her up a little to help out.

Just drive it and enjoy it and if it decides to act up then tear it down but if it's a driver you just wind up a little bit for fun once in a while
you couldn very well not ever run into any problem so good luck.

Also,after you get it all dialed in from the cam change let us know how she runs. Didn't you get this cam that was very mild for free from the previuos owner?

Also,very important,you can also go th the fiterMag site and buy a very strong oil fiter magnet designed for Baja desrt racing that will catch very microscoping metal debries and hold them on ths indie of the oil filter keeping them out of our oiling system. I have one and they really do the job and i would highly recommend it for your situation so check it out.

Good luck.....Scott

First verify your guage is accurate by checking it with another guage- I screwed up a guage once when too much pressure went to it. As a rule you need 10psi for every 1000rpm, so if this engine is going to turn 6000 then it better have about 60psi oil pressure at 6000. I've noticed similar but smaller drops in pressure with the last two motors built in my garage and I relate it to the relief spring losing tension. Both motors stabilized with adequate pressure and haven't lost any more pressure but it is frustrating. I did filter cuts and inspections on the first three oil changes with no major particles found. Neither engine lost a cam and both were broke in easy with perfect clearances. I would be willing to bet your oil pump gears and housing lost some life chewing up those cam pieces. If it were my engine and the oil pressure wasn't up to snuff I'd pull it and do an inspection while also replacing the oil pump. The bearings should be OK if the filter was doing it's job but take a look at them anyway just to be sure. The oil pump is definately a replace item if anything got through the pickup screen. Running thick oil just masks the problem- put enough stp oil treatment in a motor and it'll hide a rod knock for a little while. Do it right, less stress, more piece of mind. graemlins/beers.gif