I have a seriously modded C5 (427, forged internals, F1C Procharger, etc.) that I just had updated with Trick Flow heads and a more aggressive tune. The new shop strongly advised that I ditch the synthetic oil and go back to the dino stuff because more aggressive cam profiles don't like the synthetic. What say you?

 

Something like that may have applied back in the days, is he a old school eng.builder?

I would stick with the synthetic with the correct weight that compliments your bearing clearances.

 

I am not fool enough to correct a pro garage, I couldn't go that far away from a stock engine without a detailed engine use and care guide in one hand , every time time I twisted the ignition key.with the other.

but

At my skill level, I would look for a second or third opinion before making such a somewhat radical and unquestionably serious lubrication decision. I would certainly call the mobil 1 advice line, it's free, or reach out to another favored brand for advice, or any knowledgeable professionals you can find in the lubrication field. Maybe a few other builders or an advice line from a cam company, anything is better than rolling into a wallet risky situation without a clear understanding of your decision.

I would think any Dino oil additive packages needed to run your cam could also be found in a syn oil, if I take a logical guess . I learned a lot about additive packages over at "bob is the oil guy", they have tables of brands and different additive packages in the various products., somewhere there among the discussion groups.

Even surgical doctors get hung up on what has always worked well in the past, and why change away from something has put food on the table for twenty years, so they don't risk failure and skip updating to the latest best practice.

I am not knocking your guy, I just don't understand his reasons. ( I just threw that last unnecessary comment because this is the internet, and some are always looking for foxholes and flame throwers)

I see front line race cars that run fine on syn oil all the time , and jet engine lubrication Is only possible with synthetic oil . Consider that pro top fuel drag cars stress pistons into the plastic stage, right before solid metal breaks, with every pass, on syn oil. I just don't understand the dyne oil advice, Today, syn oil is used for break in oil, which , as you know, was the last required need it had in the piston world , before advances in machining gave syn that role also.

Years ago I watched /John Force (Big deal pro drag racer) show tear down parts on TV, that looked brand new, saying the car hadn't had any oil failures since they switched to syn oil, oiling system failures, yes, but no lubrication failures like they used to get.

if he was pitching for his Castroil sponsors, he probably would have mentioned them by name, he is not a subtle guy in TV presentations. Anyway, it convinced me, my next new Ford Explorer got syn oil, I kept it for maybe ten years, and the oil consumption was unchanged from new during that time.

If one really wants to split hairs, one can go further, into the cooling capacity of synthetic oil , but because your engine is so far from stock cooling needs, this consideration might not even apply. It is not obscure knowledge, but is seldom a consideration brought forward in LS1 discussions.

In designing the LS1, one reason that syn oil is required, is that every design of the block had too many flash points, the normal hot sports where coolant instantly vaporizes as it passes.

They couldn't get the even temperatures needed on dyne oil. I suppose syn oil has better heat transfer , because the reading said synthetic oil was the answer. in a stock LS1, you know what the design projections were , 200, 000 miles. And in testing , they satisfied those design goals, needed because failing smog tests on a massive level is not cheap.

Your car is so far from stock, I am sure the cooling system is a match. I just figured every little scrap of information might help, if your decision gets difficult.

I usually only offer advice on real basic stuff, , like rubber side down, keep the shiny side up.

 

Dang it man, you beat my effort towards advice in two sentences,

I guess I should have limited my advice to keep the shiny side up.

 

One other thing to consider, when discussing the effect of heat on motor oils, is that the current Corvettes are "bottom feeders", meaning that while they do have fans in their cooling systems, the cars don't draw a lot of air unless they're in motion. I see to recall that was a factor in specifying syn oil for the Corvettes, as they, by nature, run hotter.

 

The new shop has no clue. Your engine has roller lifters which do not need "Dino" oil. There is a lot of information about this on line, a typical example from Mobil 1:

https://mobiloil.com/en/article/car-...nventional-oil

 

Is your procharger F1 self contained or fed oil from the oil pan? If it's fed from the oil plan, you DEFINITELY want to run synthetic. The procharger head units require synthetic lubrication.

 

Getting my car back from a race shop with 20 yrs experience after they went in and stopped all my oil leaks on my 03 Coupe Stock. This was on the bottom of the invoice as to his view on high performance engines.
I had bought my own oil > 10w30 high mileage Mobil one and a Mobil one filter which they used after all was back together.

Due to current oil regulations Ragin racin suggest the use of

Valvoline VR1 10W30 synthetic oil to handle the extra load and

friction of installed high performance parts

 

You need synthetic.

Your car runs at a higher operating temperature by design, and depending on the tune could run even hotter at points within the trim scale. A 'dino' oil is going to break down much quicker since it cannot handle the higher operating temperatures that synthetic can, which will cause everything from faster internal wear to you possibly even seeing coolant loss when it vaporizes.

Something you will indeed want to ascertain however is what weight oil you need to run. Depending on the build it could call for a specific weight oil. Considering your builder is giving you fairly poor advice on not running synthetic I don't know if they would be the ones I would question about oil weight. Problem though is that there the ones that would know the tolerances. Unless you received a copy of the blueprint when the engine was put together with lists of clearances it'd be a shot in the dark going to someone else.

 

Yea, go back to 1930's oil......thats a REAL GOOD IDEA.!!...