1969 Pontiac

[69P]

Hey guys,

I want to start by asking suggestions on what oil might be best for my car. I have a 1969 Pontiac LeMans. The car has a Pontiac 350 with large valve 400 heads and and aftermarket cam. The motor that it has was rebuilt by my father about 12-15 years ago, and has no more than 9000 miles on it. The heads have been freshly redone, so they need to be broke in. The guy that put the 8000 ish miles on the motor probably used the cheapest oil he could get and might have changed the oil once or twice...

I currently use Castrol GTX convention 10W-40, about to switch to 10W-30 for the winter. I also use a quart of Lucas oil stabilizer each oil change as I find that this has smoothed up my motors in the past. My main area of concern is that these motors were made with the oils in the day that has high levels of ZDDP. I am concerned that I need to add more ZDDP to allow my engine to lubricate properly and wear correctly. Being an engineer I also wonder about how the new Boron compounds compare to the ZDDP that it has replaced.

Any input would be highly appreciated!

 

[CharBaby]

WELCOME!

You will find here that, this site isn't crazy about Lucas Products particularly the Oil Stabilizer.

And most will suggest a 5W40 or 10w30 diesel motor oils, I believe.

 

[OVERKILL]

What are the spec's on the cam? Ultimately that's going to determine whether you need additional ZDDP or not. For reference, we broke-in and ran for a number of years a Lunatti voodoo in my buddy's dad's SBC, which is about the wildest series of readily available flat tappet camshafts on nothing more than Esso (Mobil) 15w-40. We had no wear issues with the camshaft or anything else in that motor.

 

[CATERHAM]

Hey welcome to BITOG!

First forget the Lucas Oil thickener.
I'd suggest Quaker State Defy 5W-30 for year round use.
I don't know if your engine actually needs higher AW additive levels like ZDDP but Defy has it.

Do you have an oil pressure gauge?

 

[StringerOne]

I would suggest a high quality HEAVY DUTY engine oil with API service CJ-4/SN in 10W-30, 15W-40 or or synthetic 5W-40. Brands vary, but try MOBIL DELVAC, SHELL ROTELLA or SUPERTECH (Warren). All these CJ-4/SN HEAVY DUTY engine oils help the Big Rigs go a million miles or more. I'm not an engineer or scientist; the wear quality is good for these oils because of the longevity of the engines. Using a quality oil filter would be beneficial, also. Good luck.

 

[69P]

The cam shaft is a little more noticeable than the factory 2 barrel 350 cam, since thats what it had in there to begin with. Id say somewhere in the realm of 268/268 duration and probably no more than 0.450 lift and thats probably an overestimate at that. Still a mild cam for a Pontiac.
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.
Can anyone explain the reason to turn away from the lucas oil stabilizer? IT really seems to coat the moving parts well and help with dry starts from what I noticed.

Thanks for the welcome and the eagerness to help!

 

[nwjones18]

I think I'd be using DEFY 10w-30 myself. But I'm sure that or any of the suffested HDEO will serve you well.

 

[abycat]

for sure skip the Lucas. I'd run a good quality syn like pp. In a 5w30.

 

[OVERKILL]

Originally Posted By: 69P
The cam shaft is a little more noticeable than the factory 2 barrel 350 cam, since thats what it had in there to begin with. Id say somewhere in the realm of 268/268 duration and probably no more than 0.450 lift and thats probably an overestimate at that. Still a mild cam for a Pontiac.
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.
Can anyone explain the reason to turn away from the lucas oil stabilizer? IT really seems to coat the moving parts well and help with dry starts from what I noticed.

Thanks for the welcome and the eagerness to help!


With that kind of oil pressure hot at idle I'd step it up to a 15w-40 or 5w-40. That's too low for my comfort level, but I really don't know what is "normal" for this engine. An SBF and any of the SBC's I've been involved in have always had at least double that at idle; north of 30psi.

 

[JHZR2]

A 10w-30 HDEO should be ideal. Amsoil hot rod oil if youre so inclined will work too.

Depending upon cam/spring pressure, you may need to boost ZDDP. Redline makes a break-in additive, there are some zddp equivalent adds that can be used too...

 

[Merkava_4]

Originally Posted By: 69P
My main area of concern is that these motors were made with the oils in the day that has high levels of ZDDP.


That's exactly why I'd run 10W-40 or 15W-40 year round with a bottle of Justice Brothers ZDDP.

 

[morepwr]

Welcome to the site! I use 10W-30 Rotella "diesel" oil in my older cars with flat tappet cams and have had zero problems. I have also ran Valvoline VR1 with no problem but it can be harder to find and more $$ so I went to the Rotella because it is very inexpensive. You do not need to add the Lucas to these oils and can use that money toward a quality oil filter.

 

[CATERHAM]

Originally Posted By: 69P
The cam shaft is a little more noticeable than the factory 2 barrel 350 cam, since thats what it had in there to begin with. Id say somewhere in the realm of 268/268 duration and probably no more than 0.450 lift and thats probably an overestimate at that. Still a mild cam for a Pontiac.
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.
Can anyone explain the reason to turn away from the lucas oil stabilizer? IT really seems to coat the moving parts well and help with dry starts from what I noticed.

Thanks for the welcome and the eagerness to help!
Originally Posted By: 69P
The cam shaft is a little more noticeable than the factory 2 barrel 350 cam, since thats what it had in there to begin with. Id say somewhere in the realm of 268/268 duration and probably no more than 0.450 lift and thats probably an overestimate at that. Still a mild cam for a Pontiac.
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.
Can anyone explain the reason to turn away from the lucas oil stabilizer? IT really seems to coat the moving parts well and help with dry starts from what I noticed.

Your OP at high rev's is a more reliable measure.
50 psi fully hot is as good target and with a fresh engine you should be able to maintain that on the the QS Defy 5W-30 which is heavier than some 10W-30s.

The Lucas oil Stabilizer is just a polymer thickener. It's a very much old school way to thicken what used to be very shear prone oils in service. I keep a bottle of a similar product in my tool box when I go to the track. It's a quick and easy way of boosting OP in a rush when the sump is already full. I usually wind up giving it away to a fellow racer who has a OP problem of one sort or another. But it's better to use a proper fully formulated oil to achieve your desired OP.

 

[69P]

I mean my oil pressure is in the forties cruising down the highway in the 55mph range. That seems acceptable to me since its around 2200rpm, and I think I have a 60 psi oil pump.

Does that seem logical to anyone else?

If I had an oil galley plug missing, would that account for the low idle oil pressure, but acceptable cruising pressure?

 

[CATERHAM]

In the 40s at 2,200 rpm sounds okay but next time you take it for a spin check you hot OP at 4,000-5,000 rpm. That when you want to see 50 psi.

 

[CATERHAM]

To add to that, you want 50 psi at high rev's but something less than 60 which is from the sound of things your by-pass setting.
That's the window you want your oil viscosity choice to fall within.

 

[ThirdeYe]

I'd use Rotella T6 Synthetic 5W-40, personally. Nice car! Can we see some pics?

 

[Red91]

+1 on Defy 5W-30.

 

[Greasymechtech]

I'd recommend any euro or diesel 0w40 or 5w40 oil. Either have plenty of additives and won't need supplements.

 

[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?