Anything but Stock (NASCAR)

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MolaKule

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I am summarizing an article I saw in TLT magazine by Dr. Ed Becker regarding NASCAR.

Engines are 358 cu. in. and cost between $45,000 and $80,000.

Engine displacement, combustion chamber shape, and valve train arrangement have to adhered to by NASCAR rules.

Some parts, such as cylinder blocks and heads, have to be purchased from approved suppliers.

Since the racing oil is only used for one race and doesn't require a long life, it need not contain components used in a daily-driver oil. The Oil used has to have an anti-friction component and large amounts AW chemistry such as ZDDP or organic AW components. Low and stable viscosity must allow minimal shear losses but high enough to maintain hydrodynamic films. No dispersant or detergent is used. Each racing team purchases it's own specially blended oil and each formula is top secret.

Originally Posted By: Dr. Ed Becker
Creative tribology is used for surface treatments. The piston assembly has no less than five surface coatings and is machined to exceptionally high tolerances to precisely fit the bore.

The piston pin has a Diamond Like Coating (DLC) applied. The piston bore has an electrolysis nickel coating for compatibility with the DLC treatment. The piston skirts have a molybdenum sulfide coating. The top ring has a titanium nitride coating to reduce friction and wear, and the top ring groove has a plasma-sprayed aluminum oxide coating to prevent top ring pound-out.


Remember, all of the above surfaces are coated with solid metallic or DLC coatings and not part of the oil additive package.

As for reliability, the engine only has to last long enough to finish the race.
 
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I wonder what the HTHSV they target when formulating these oils.

Very interesting that there is no detergent or dispersant, I would have thought they contained some.
 
If a specially selected ester is used in the oil mix, there is no need for conventional dispersant/detergent chemistry.
 
What is interesting about the 358ci engines, are ones out in the open require the valvesprings to be replaces every 3,000 miles or so if you do not limit the RPM under 7k. They will rev over 10K fairly easy without failure, especially the fuel injected ones.

Generally the engines are leased, you are not allowed to purchase them for the most part. RoushYates is very protective over the FR9. You can buy the block and heads from Summit, but they are only sold as-cast. Hendrick, Childress, Triad, and TRD do leases also. Some teams have been allowed to purchase plate engines, usually the backmarkers and from what I remember it was one of the Chevy suppliers that allowed it. There was one team, PPR, the team that Josh Wise drove for that ran the DogeCoin scheme were Ford bodies at all tracks except the plate ones. They were able to buy some Chevy plate engines so they ran the Chevy SS body on plate tracks.

The newer engines are externally very similar in appearance. I have pics of them all and I bet with the valve covers off I would have a hard time telling the difference between a FR9 and a R07.

I don't understand why people think a NASCAR should be a factory stock car. They haven't been since the permier touring series was known as NASCAR Strictly Stock. To quote a movie, "There is nothing stock about a stock car."
 
Maybe that's similar to some of the redline race oils. Think they are ester. I guess longivity isnt the issue as long as it does what it needs to.
 
Originally Posted By: HerrStig
What oil goes into dragster engines?


Back in the days when Kenny Bernstein was racing the Budweiser King Top Fuel car, they were forced to shut down the engine in the staging lanes because of zero oil pressure. It turns out whoever was responsible for putting in the oil after the between round rebuild, forgot to do so. They were interviewing Kenny, who was very P.O.'ed at the time. And sitting on a table right behind him, were several jugs of Lucas S.A.E. 50W Racing Oil. He pointed to it and mentioned that was why they had no oil pressure.
 
In 1990 i was on a top fuel team.We were testing in Bakersfield cal.That was the year Kenny was switching to top fuel.His team and our team were the only ones testing.I witnessed one of his crew memebers filling up Quaker State (EMPTY) qrt bottles with Kendall 70 wt. I asked if QS was ok with that? His response was they didnt care as long as people saw Quaker State on the side of the car and them using Quaker State oil bottles while pouring oil into the car...
 
Originally Posted By: HerrStig
What oil goes into dragster engines?


If you're referring to T/F, currently many (but not all) teams use Redline 70 wt nitro race oil.
 
For the local alchy-fueled oval track racers (carbeurated engines) they use my 20W50 Blend.
 
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Current Cup engines are designed to the limit of the rules.
NASCAR specifies iron blocks, maximum bore spacing of 4.5", maximum bore of 4.185", max compression rato of 12:1, and probably some other things around cam bearing diameter.
The entry of Toyota into Cup prompted NASCAR to set limits, or they would have been able to design a doomsday weapon since they had no 'stock' pushrod V8. I have read that the Toyota was very close to the Dodge in design.
GM's latest engine was introduced in 2007, and it uses Compacted Graphite Iron (CGI) for the block, which allows a very thinwall block that is still very strong. Grainger & Worrall in England casts the block and brags that none have ever failed in competition. GM keeps lobbying NASCAR to allow them to introduce a new design, but since they are still competitive, NASCAR won't allow it. (Given the dominance of Joe Gibbs' Toyotas this year, I think they should reconsider.)
NASCAR allowed the introduction of roller lifters into Cup last year, and instituted a rev limit that brought peak engine speeds down from ~9700 to ~8700 rpm, and a loss of about 100 HP. Nobody seems to mind very much, though.
 
bdcardinal,

About those valve springs. Does running the engine at high rpms harm the spring? Like, say, it becomes spongy like and old strut and is slower to close and will float.


Does that describe what you were talking about when you said they werent good past 3000 miles if ran over 7000rpm?
 
Ya a guy I knew had one and said it was in a manual from RCR/ECR. He tried to push it and it quickly felt like it lost power. Also turning down the RPMs meant a rebuild could be pushed out.

The previous engines that were based on the Gen 1 SBC and Windsor motors could probably last longer without all the exotic parts.
 
Originally Posted By: mjoekingz28
bdcardinal,

About those valve springs. Does running the engine at high rpms harm the spring? Like, say, it becomes spongy like and old strut and is slower to close and will float.


Does that describe what you were talking about when you said they werent good past 3000 miles if ran over 7000rpm?


Exactly, if the spring isn't strong enough. It will float, and the valve won't open and close all the way. Loss of power occurs and the engine will sound funny. But in reality it probably easier on the valve itself, unless the piston contacts the valve. Springs that are stiff to prevent valve float at high rpm are hard on valve stems because of the hard slamming of the valve head against the valve seat. If you don't have a strong enough valve, the head becomes detached from the valve stem and you have a big mess in your cylinder.
 
Originally Posted By: Srt20
Originally Posted By: mjoekingz28
bdcardinal,

About those valve springs. Does running the engine at high rpms harm the spring? Like, say, it becomes spongy like and old strut and is slower to close and will float.


Does that describe what you were talking about when you said they werent good past 3000 miles if ran over 7000rpm?


Exactly, if the spring isn't strong enough. It will float, and the valve won't open and close all the way. Loss of power occurs and the engine will sound funny. But in reality it probably easier on the valve itself, unless the piston contacts the valve. Springs that are stiff to prevent valve float at high rpm are hard on valve stems because of the hard slamming of the valve head against the valve seat. If you don't have a strong enough valve, the head becomes detached from the valve stem and you have a big mess in your cylinder.







Great!
 
Originally Posted By: mjoekingz28
bdcardinal,

About those valve springs. Does running the engine at high rpms harm the spring? Like, say, it becomes spongy like and old strut and is slower to close and will float.


Does that describe what you were talking about when you said they werent good past 3000 miles if ran over 7000rpm?


What's happening at high engine speeds is the springs get hot. Yes, there are oil spray bars to cool the springs, but the springs still get hot and fatigue. The springs do funny things. Go look at Spintron videos on Youtube.

If the spring isn't strong enough for the valve train to follow the cam profile the valve will slam into the seat in an uncontrolled manner. Weak/ineffective springs are more of a problem at high speeds than ones which are strong and performing well.
 
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