70 LT1 FT Camshaft Options

G72Zed

Veteran Member
Sep 8, 2015
3,750
Canada

Nice chart, just goes to show you how actual oil temps play a major part in viscosity choice, street machines - muscle cars and hot rods do not have, or fail to incorporate and oil temp gauge in many cases.

Most every race car I work on these days do not even have a tach, just gear it to hit the chip when you need to. But they all have a Water and oil temps gauges, along with oil and water pressure gauges, and that's it, nothing else needed.



Looks like 10w-30 is about right. Not sure what effect, if any, the lifter holes make. Probably none.
Thanks, Mark, for the chart. Good stuff.

My old notes stated only 2-5 psi drop max with the SFT centered EDM's, the offset EDM's a little more, and I've used .012 to .021 sized holes as well.

Many get their shorts in a bunch for nothing on a "low" oil pressure needle, and in the case of SFT with EDM's, the climb is worth the view without question.
 

COPO

Veteran Member
Lifetime Gold Member
Sep 15, 1999
21,610
Ontario, Canada
What’s the oil temp for a 350 high performance engine when 5w30, 10w30, 10w40, 15w40 and 20w50 are used?
 

G72Zed

Veteran Member
Sep 8, 2015
3,750
Canada
What’s the oil temp for a 350 high performance engine when 5w30, 10w30, 10w40, 15w40 and 20w50 are used?

That would depend on a lot of things I guess, like outside/underhood temp. conditions, water temps, timing, load and the engines oil capacity, and if an oil cooler is in place. And mostly how it's being run and loaded with RPM's and duration.

For me, I've used 10w30 to 20w50, easy street/highway hot summer driving, 150-160 oil temps, trails the water temp by 10-20*,

3 autocross runs back to back, 180-200

1/2 hour runs on the open road course in 90* heat, 260-285*
 
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clm69z28

Veteran Member
Oct 29, 2011
385
encinitas ca
Mark, thanks so much for the chart. I've never seen such a detailed chart for oil recommendations; helps shed some light on a misunderstood subject. I'm embarrassed to say I don't know my engine's oil temp range, I was more focused on an oil pressure gauge than the idiot light.

Since I'm in Cali, the chart suggests going up to the next viscosity level for the Methanol/E85 gas we have here. So, that would suggest going to 10w-40 or 15w50. Any thoughts on that recommendation? And the chart didn't have a break in oil section; any thoughts on what oil to use for the break in procedure? Thanks to all in advance for the good information.
 

G72Zed

Veteran Member
Sep 8, 2015
3,750
Canada
It was mentioned early on in this thread that the Driven BR30 is a great break in oil, I used this oil many times.

If your carb/fuel system is, or will be in fact tuned & setup for the E85 or lower E50-65, I would recommend the 10-40, if over the 230* oil temps, try the 15-50.

But, if your are setup and going to use E85, perhaps there was no need to lower your original CR in the first place, maybe I'm mixed up on this, if so, just ignore most of my post here.
 

clm69z28

Veteran Member
Oct 29, 2011
385
encinitas ca
Sorry G72Zed, I was mistaken in the ethanol spec; Cali has an up to 10% ethanol blend, not E85. I guess this is why I shouldn't post anything past 6:00 pm when my brain has stopped working. So, I'll go with the 10w-30. As to the break in oil, do you use it strictly for the initial break in period, then drain and replace with the 10w-30?
 

G72Zed

Veteran Member
Sep 8, 2015
3,750
Canada
LOL, no need to say sorry clm69z28, I use 94 octane pump fuel that contains 9% Ethanol as well up here, just make sure your jetting is correct, 1-2 size larger jets usually get's you there vs pure gasoline if it was jetted correctly in the first place.


As to the break in oil, do you use it strictly for the initial break in period, then drain and replace with the 10w-30?

No, I use it for the cam/ring pack break in, then change filter only and top off with the BR30 for the rest of the day's dyno session, and leave it in for 200-400 miles and go with the VR1 10/30 or the Driven 10/30 or 10/40 afterwards, no need for any additives.

More details are in post #63 to #67.
 




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