Head's spinning from what oil for 1970 chevy LT-1

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I have a new 1970 Chevy LT-1 solid lifter 350 that I've had since 1989. Currently has 200 miles on it. Ran Northland Superline 7 15w-40 diesel oil so far. Decided after reading endless posts here and on the C3 Corvette forum, that I need to change soon. So many opinions, it is so hard to make a choice. After reading the Mobil 1 info, that recommended 15w-50 for this engine with a SN rating and proper zinc levels. I decided that is heavier that I would like, so I am leaning toward their 0w-40 Euro spec oil that is SN rated with zinc. Good choice for a very rare low mi. engine? Also has to be a "over the counter oil" that I can get anywhere.
 
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Originally Posted By: eljefino
How built is this? Eg what are the valve spring pressures like?

All stock, engine Chevy sold as a crate engine in the mid 70's. 11 to 1 forged, steel crank, turbo angle plug heads. Awesome engine, runs perfect. Would eventually like to go to a hydraulic roller cam, and E85 fuel, but it runs so good now, I hate to mess with it. It still had assembly lube on the valve train when I bought it for $1000.
 
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An API SN 10W-40 can have higher zinc levels than the same API spec would allow in a 5W-30.
QS Defy 10W-40 might be a good choice.
 
Joe Mondello, a well respected man in pushrod circles recommended a product called "Cam Shield." You can add it to whatever modern oil you choose in order to pump up the ZDDP to levels that your LT-1 was intended to run on. Mondello said he was having issues with flat tappet cams in the new engines he was building that STOPPED when he began using Cam Shield. And he didn't sell Cam Shield and apparently didn't receive anything from this small company for the recommendation. I have a bottle in the garage. I've used it in a few things but can't really give a meaningful critique. Search for Mondello and Cam Shield and I'm sure you'll find an article where he recommends it. Joe Mondello was one of the great American hot rod engine masters. A master of engines like your LT-1.
 
My old man had one of those LT-1 crate engines. He put it in a '68 Camaro with a close ratio 4-speed and 4.10 12 bolt. That was 1977. I was a kid of 5 or 6. That car took my breath away. I refused to ride in it with him.
 
20W50?!?!? That's asinine. All you're going to do is waste power. It's time to drop the old school thinking with today's lubricants.


The 350 in my drag car is based off of your same engine. I have run every oil under the sun in mine (solid lifter, shifting at 6000-6500 RPM), I settled on Mobil 1 5W30 years ago. The last time I changed camshafts for a new profile, the old cam had NO MEASURABLE wear. Break it in correctly with a QUALITY camshaft and you'll be fine.

The M1 5W30 worked great for years, but if I were to change my oil in my Malibu right now, I would use the best oil (IMO) in the XOM lineup, which is 0W40.
 
10W-30 Brad penn, VR1 or amsoil Z Rod. Absolutely no need for 20W-50 at all and with the correct oil no need for any additives either. Heck if you wanted cheaper oil Rotella T6 or standard rotella 15W-40 would work good also with no additives needed. 20W-50 does nothing but add drag to the rotating assembly. I have seen it cause an engine to sheer off a standard non hardened oil pump to distributor shaft.
 
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Valvoline VR1 10W30 is readily available and cost effective. I would try that and see how the engine likes it.

vv20510w30vriracing.jpg
 
Nix on the 20w50. I doubt that GM specified anything thicker than 30 for that engine when it was new.
Valvoline VR1 10w30 conventional.
Or buy a bottle of ZDDPlus and use it to supplement any good SN 5w30 synthetic.
 
You can't go wrong with the M1 15W-50 unless you're trying to start it in zero degree weather all the time. I don't think that old LT1 cam was so radical that 0W-40 or even 5W-30 wouldn't work in the M1 flavor. Defy is also a good choice.
 
Like above 10w30 vr1 is all you will need. One of our old 360s was tore down at close to 15k miles and 400 1/4 passes running at .612 lift and 408lb/inch Springs on solid lifters. Cam went right back in and all we did was rering.

A proper break in for the cam is more beneficial than anything. 20w50 isn't needed, not even in our 1600hp Hemi.
 
Some Joe Gibbs and Amsoil oils have an extra additive to prevent rust when the engine sits for a long period of time. They also have extra ZDDP as well.

It is what I plan to use when I eventually get and RV
 
Originally Posted By: artificialist
Some Joe Gibbs and Amsoil oils have an extra additive to prevent rust when the engine sits for a long period of time. They also have extra ZDDP as well.

It is what I plan to use when I eventually get and RV


Again unneeded for 99% of engines. 5w30 SN is enough for flat tappets and extended sitting.

The 360 I mentioned ran 13.2 compression,.612 lift cam on solid lifters and a 150 shot of nitrous. When tore down (100% vr1) everything was perfect.

I would throw pyb, quad, or any other SN 5w30 in any of our cars besides the Hemi. Zddp is fine in modern oils.
 
Originally Posted By: bubbatime
Valvoline VR1 10W30 is readily available and cost effective. I would try that and see how the engine likes it.

vv20510w30vriracing.jpg



Don't they also make this (one viscosity, 10W-30 ONLY) in a synthetic version as well??
 
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