If a 30 grade gives you enough oil pressure at hot idle and hot load, then overly thick oils do nothing but increase bypass events.
1969 Pontiac
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Originally Posted By: chainblu
I think you guys are wasting your time on this one. Even though he asked for advice, he's just waiting for someone to tell him what he wants to hear.
Thats not true. I have just not heard much logic as to why choose certain oils. A few of you have been great, but I will never blindly accept a straight answer of you should use XXWXX.
I think you guys are wasting your time on this one. Even though he asked for advice, he's just waiting for someone to tell him what he wants to hear.
Thats not true. I have just not heard much logic as to why choose certain oils. A few of you have been great, but I will never blindly accept a straight answer of you should use XXWXX.
Originally Posted By: 901Memphis
If a 30 grade gives you enough oil pressure at hot idle and hot load, then overly thick oils do nothing but increase bypass events.
This is the answer.
OP needs oil temperature and oil pressure together to make a real reasoned decision.
FWIW, I used to race Pontiacs in the old daze, they are not high revvers by nature, can't imagine why they would need 40w or 50w unless you were road course tracking the vehicle...
If a 30 grade gives you enough oil pressure at hot idle and hot load, then overly thick oils do nothing but increase bypass events.
This is the answer.
OP needs oil temperature and oil pressure together to make a real reasoned decision.
FWIW, I used to race Pontiacs in the old daze, they are not high revvers by nature, can't imagine why they would need 40w or 50w unless you were road course tracking the vehicle...
Originally Posted By: SteveSRT8
Originally Posted By: 901Memphis
If a 30 grade gives you enough oil pressure at hot idle and hot load, then overly thick oils do nothing but increase bypass events.
This is the answer.
OP needs oil temperature and oil pressure together to make a real reasoned decision.
FWIW, I used to race Pontiacs in the old daze, they are not high revvers by nature, can't imagine why they would need 40w or 50w unless you were road course tracking the vehicle...
As long as bearing wear is acceptable, tune oil viscosity to obtain correct oil pressures. Would you agree with that statement? Im thinking hot idle should be around 25 psi. Although that might also knock out the 10 psi per 1000rpm rule of thumb if I have a max pump of 60 psi. If I recall correctly, the only Pontiac motors designed with the higher 80psi oil pumps were mid 70s models SD 455.
Originally Posted By: 901Memphis
If a 30 grade gives you enough oil pressure at hot idle and hot load, then overly thick oils do nothing but increase bypass events.
This is the answer.
OP needs oil temperature and oil pressure together to make a real reasoned decision.
FWIW, I used to race Pontiacs in the old daze, they are not high revvers by nature, can't imagine why they would need 40w or 50w unless you were road course tracking the vehicle...
As long as bearing wear is acceptable, tune oil viscosity to obtain correct oil pressures. Would you agree with that statement? Im thinking hot idle should be around 25 psi. Although that might also knock out the 10 psi per 1000rpm rule of thumb if I have a max pump of 60 psi. If I recall correctly, the only Pontiac motors designed with the higher 80psi oil pumps were mid 70s models SD 455.
M1 0W-40 or 15W-50 - both should boost your idle OP. And you can use both year round in KY IMO. That being said, Caterham's recommendation of Defy 5W-30 should also be fine. Those aren't big spring pressures and the 400 isn't a hi-revving motor. No additives.
25-35 psi hot idle sounds about right. I can't imagine anything needing more than that especially with all the good anti wear layers the modern oils put down.
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Originally Posted By: 69P
Originally Posted By: 901Memphis
Originally Posted By: Merkava_4
Originally Posted By: 69P
Why choose 5w over 10w ?
Also im hesitant to run Quaker State oil. Ive always heard about quaker state and a notorious grey buildup. Have you guys heard or experienced this?
If you want, I can give you the name of an automotive machinist that's been in the business for well or 20 years and he just so happens to own a '69 Pontiac Lemans. I'd take his word for gospel if it was me.
I can guarantee you he'd never recommend 5W-30 in a million years.
Old timers are the worst, especially ones who think they know best. I bet he's a 10w40 for everything guy.
That old timer would be smart to recommend a 10W40 oil for it. At least he wouldnt have recommended a 0W oil for it, that wouldnt be a good idea. I would like to hear what he has to say.
Why would a 0W-xx be a bad idea? M1 0w-40 is more than adequate for this application. However, since you likely won't be running extended drain intervals or doing extreme cold temperature starting, it would be wasted in this application. That's why I mentioned a 15w-40 or 5w-40 earlier.
Originally Posted By: 901Memphis
Originally Posted By: Merkava_4
Originally Posted By: 69P
Why choose 5w over 10w ?
Also im hesitant to run Quaker State oil. Ive always heard about quaker state and a notorious grey buildup. Have you guys heard or experienced this?
If you want, I can give you the name of an automotive machinist that's been in the business for well or 20 years and he just so happens to own a '69 Pontiac Lemans. I'd take his word for gospel if it was me.
I can guarantee you he'd never recommend 5W-30 in a million years.
Old timers are the worst, especially ones who think they know best. I bet he's a 10w40 for everything guy.
That old timer would be smart to recommend a 10W40 oil for it. At least he wouldnt have recommended a 0W oil for it, that wouldnt be a good idea. I would like to hear what he has to say.
Why would a 0W-xx be a bad idea? M1 0w-40 is more than adequate for this application. However, since you likely won't be running extended drain intervals or doing extreme cold temperature starting, it would be wasted in this application. That's why I mentioned a 15w-40 or 5w-40 earlier.
I agree. Considering how cheap M1 0W-40 is in the States it would be a better choice to a 5W-40 and much lighter than a 15W-40.
My only reservation with it would be that it's still likely heavier than necessary. I suspect the OP will be able to maintain the required minimum oil pressure at high rev's on the fairly heavy (HTHSV 3.3-3.4cP) QS Defy 5W-30.
My only reservation with it would be that it's still likely heavier than necessary. I suspect the OP will be able to maintain the required minimum oil pressure at high rev's on the fairly heavy (HTHSV 3.3-3.4cP) QS Defy 5W-30.
Ran and built lots of Pontiacs...always used 20/w50 Valvoline Dino in hot climates and 10/w30 Valvoline Dino in cold climates.
Oil pressure at idle with M54 pumps was always about 30-35psi (hot) with .0015" to .0020" bearing clearances, a little lower with the 10/w30...we also made identical HP/TQ numbers on the dyno with either viscosity at operating temps.
This 413 CID Pontiac (masquerading as a 455) made 400 HP @ 6200 rpm...
Oil pressure at idle with M54 pumps was always about 30-35psi (hot) with .0015" to .0020" bearing clearances, a little lower with the 10/w30...we also made identical HP/TQ numbers on the dyno with either viscosity at operating temps.
This 413 CID Pontiac (masquerading as a 455) made 400 HP @ 6200 rpm...
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Those pistons bring back memories! My buddy used the same family of SpeedPro's with the coated skirts in his N2O SBF build a number of years back!
Originally Posted By: 69P
I do have an oil gauge and on start up it shows 60psi and when full warmed up and ran a little it shows 10-15 psi on 600ish rpm idle. It seems low to be so freshly rebuilt, but it seems smooth so im not sure.
What are your bearing clearances??? They define idle oil pressure. Also, we ALWAYS sealed the oil pump cover with Loctite 574 Flange Sealant because we have seen BIG pressure leaks between oil pump body/cover on Pontiacs with their thin, metal covers.
The oil pump to block gasket is another potential leak source.
We saw better hot idle oil pressure when we used AC (PF-61 with headers) on Pontiacs...FWIW
I do have an oil gauge and on start up it shows 60psi and when full warmed up and ran a little it shows 10-15 psi on 600ish rpm idle. It seems low to be so freshly rebuilt, but it seems smooth so im not sure.
What are your bearing clearances??? They define idle oil pressure. Also, we ALWAYS sealed the oil pump cover with Loctite 574 Flange Sealant because we have seen BIG pressure leaks between oil pump body/cover on Pontiacs with their thin, metal covers.
The oil pump to block gasket is another potential leak source.
We saw better hot idle oil pressure when we used AC (PF-61 with headers) on Pontiacs...FWIW
P.S. Here is the grind I used in most of my Pontiacs, a custom profile developed by Tim Goolsby and I at Ultradyne...
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69P, I talked to my machinist friend today.
For your application, he recommends Joe Gibbs Hot Rod Oil 15W-50, or Shell Rotella 15W-40.
He said the Rotella barely has enough zinc in it to protect the camshaft. He said if you go with the Rotella, he recommends adding a bottle of Justice Brothers zinc additive just to be safe. If you go with the Joe Gibbs, it has the necessary zinc level in it already. So there you have it. You can take the advice of an engine builder with over 20 years experience building race engines, or you can take the other's advice and wipe your cam out. Your choice.
For your application, he recommends Joe Gibbs Hot Rod Oil 15W-50, or Shell Rotella 15W-40.
He said the Rotella barely has enough zinc in it to protect the camshaft. He said if you go with the Rotella, he recommends adding a bottle of Justice Brothers zinc additive just to be safe. If you go with the Joe Gibbs, it has the necessary zinc level in it already. So there you have it. You can take the advice of an engine builder with over 20 years experience building race engines, or you can take the other's advice and wipe your cam out. Your choice.
Originally Posted By: Merkava_4
69P,
I talked to my machinist friend today. For your application, he recommends Joe Gibbs Hot Rod Oil 15W-50 or Shell Rotella 15W-40. He said the Rotella barely has enough zinc in it to protect the camshaft. He said if you go with Rotella, he recommends adding a bottle of Justice Brothers zinc additive. If you go with the Joe Gibbs, he says it has plenty of zinc in it already. So there you have it. You can take the advice of an engine builder with over 20 years experience building race engines, or you can take the other's advice and wipe your cam out. Your choice.
I've never worried much about zinc on a street motor. We always broke cams in with Valvoline racing oil, usually a straight SAE 30, and never had any problems. Although Dad is officially retired, we still build a few for old customers and we still run Valvoline 20/w50 or 10/w30 racing oils, changed about every 3,000 miles if the vehicle is carbureted.
The biggest problem with camshaft failures is open spring pressure. You need to stay under 300 lbs open pressure on a street motor with a flat tappet camshaft. A few years back, Comp Cams increased the pressure on their #995 (IIRC) springs due to a very dynamically unstable lobe profile, which required more open pressure to control the valves. This resulted in a lot of flat camshafts.
Joe Gibbs, Brad Penn, or Valvoline Racing Formula would all give excellent service. You can probably find the VOA's here for all of them...
We know a little bit about engine building...
69P,
I talked to my machinist friend today. For your application, he recommends Joe Gibbs Hot Rod Oil 15W-50 or Shell Rotella 15W-40. He said the Rotella barely has enough zinc in it to protect the camshaft. He said if you go with Rotella, he recommends adding a bottle of Justice Brothers zinc additive. If you go with the Joe Gibbs, he says it has plenty of zinc in it already. So there you have it. You can take the advice of an engine builder with over 20 years experience building race engines, or you can take the other's advice and wipe your cam out. Your choice.
I've never worried much about zinc on a street motor. We always broke cams in with Valvoline racing oil, usually a straight SAE 30, and never had any problems. Although Dad is officially retired, we still build a few for old customers and we still run Valvoline 20/w50 or 10/w30 racing oils, changed about every 3,000 miles if the vehicle is carbureted.
The biggest problem with camshaft failures is open spring pressure. You need to stay under 300 lbs open pressure on a street motor with a flat tappet camshaft. A few years back, Comp Cams increased the pressure on their #995 (IIRC) springs due to a very dynamically unstable lobe profile, which required more open pressure to control the valves. This resulted in a lot of flat camshafts.
Joe Gibbs, Brad Penn, or Valvoline Racing Formula would all give excellent service. You can probably find the VOA's here for all of them...
We know a little bit about engine building...
Originally Posted By: Merkava_4
69P, I talked to my machinist friend today.
For your application, he recommends Joe Gibbs Hot Rod Oil 15W-50, or Shell Rotella 15W-40.
He said the Rotella barely has enough zinc in it to protect the camshaft. He said if you go with the Rotella, he recommends adding a bottle of Justice Brothers zinc additive just to be safe. If you go with the Joe Gibbs, it has the necessary zinc level in it already. So there you have it. You can take the advice of an engine builder with over 20 years experience building race engines, or you can take the other's advice and wipe your cam out. Your choice.
You can always add zinc to any grade of oil, I just don't think you need a 40 grade to maintain adequate pressure. QS defy 5w30 already has approximately 1200+ Zinc and around 1000 phosphorus.
The last Rotella 15w40 VOA I saw had 1504 ppm zinc and 1350 phosphorus. Anyone who thinks 1500 ppm zinc is "barely enough" clearly doesn't understand lubrication fully.
1500 ppm zinc is what I would call maximum needed for any flat tappet high spring pressure application. Once you get too much higher than 1500 ppm, your getting corrosive.
69P, I talked to my machinist friend today.
For your application, he recommends Joe Gibbs Hot Rod Oil 15W-50, or Shell Rotella 15W-40.
He said the Rotella barely has enough zinc in it to protect the camshaft. He said if you go with the Rotella, he recommends adding a bottle of Justice Brothers zinc additive just to be safe. If you go with the Joe Gibbs, it has the necessary zinc level in it already. So there you have it. You can take the advice of an engine builder with over 20 years experience building race engines, or you can take the other's advice and wipe your cam out. Your choice.
You can always add zinc to any grade of oil, I just don't think you need a 40 grade to maintain adequate pressure. QS defy 5w30 already has approximately 1200+ Zinc and around 1000 phosphorus.
The last Rotella 15w40 VOA I saw had 1504 ppm zinc and 1350 phosphorus. Anyone who thinks 1500 ppm zinc is "barely enough" clearly doesn't understand lubrication fully.
1500 ppm zinc is what I would call maximum needed for any flat tappet high spring pressure application. Once you get too much higher than 1500 ppm, your getting corrosive.
Originally Posted By: 901Memphis
You can always add zinc to any grade of oil, I just don't think you need a 40 grade to maintain adequate pressure. QS defy 5w30 already has approximately 1200+ Zinc and around 1000 phosphorus. The last Rotella 15w40 VOA I saw had 1504 ppm zinc and 1350 phosphorus. Anyone who thinks 1500 ppm zinc is "barely enough" clearly doesn't understand lubrication fully.
1500 ppm zinc is what I would call maximum needed for any flat tappet high spring pressure application. Once you get too much higher than 1500 ppm, your getting corrosive.
Again, Idle oil pressure is controlled by bearing clearances and connecting rod side clearances. In hot climates, run a 20/w50 and if it is cold, run a 10/w30. Joe Gibbs or Brad Penn would be fine to, as would Rotella.
Valvoline Racing Formula has 1200ppm ZDDP, FWIW.
Again, watch valve spring open pressures - that is the #1 camshaft lobe/lifter killer. Stay under 300 lbs (275 lbs is ideal) on a street motor and you won't have any problems. ZDDP will not protect you from high open valve spring presures.
You can always add zinc to any grade of oil, I just don't think you need a 40 grade to maintain adequate pressure. QS defy 5w30 already has approximately 1200+ Zinc and around 1000 phosphorus. The last Rotella 15w40 VOA I saw had 1504 ppm zinc and 1350 phosphorus. Anyone who thinks 1500 ppm zinc is "barely enough" clearly doesn't understand lubrication fully.
1500 ppm zinc is what I would call maximum needed for any flat tappet high spring pressure application. Once you get too much higher than 1500 ppm, your getting corrosive.
Again, Idle oil pressure is controlled by bearing clearances and connecting rod side clearances. In hot climates, run a 20/w50 and if it is cold, run a 10/w30. Joe Gibbs or Brad Penn would be fine to, as would Rotella.
Valvoline Racing Formula has 1200ppm ZDDP, FWIW.
Again, watch valve spring open pressures - that is the #1 camshaft lobe/lifter killer. Stay under 300 lbs (275 lbs is ideal) on a street motor and you won't have any problems. ZDDP will not protect you from high open valve spring presures.
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With flat tappet, definitely. With hydraulic and solid roller you can go much heavier.
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