Piston oil squirters in NASCAR engines

General engine tech -- Drag Racing to Circle Track

Moderator: Team

User avatar
ptuomov
Guru
Guru
Posts: 3587
Joined: Fri Aug 07, 2009 3:52 am
Location:

Piston oil squirters in NASCAR engines

Post by ptuomov »

Anyone had a look inside a newish NASCAR engine? I hear they have four or five piston oil cooling jets per cylinder. Which spots in the piston underside do all those four or five jets spray?
Paradigms often shift without the clutch -- https://www.youtube.com/watch?v=cxn-LxwsrnU
https://www.instagram.com/ptuomov/
Put Search Keywords Here
Fusion Works
Member
Member
Posts: 177
Joined: Tue Jun 09, 2015 10:24 am
Location: Huntsville, AL
Contact:

Re: Piston oil squirters in NASCAR engines

Post by Fusion Works »

I also wonder how this contradicts with the oil control on the cylinder walls, pushing that much oil up onto the piston?
User avatar
4sfed
Pro
Pro
Posts: 338
Joined: Sun Mar 13, 2011 11:32 pm
Location:

Re: Piston oil squirters in NASCAR engines

Post by 4sfed »

In general, the purpose of an oil squirter is to cool the piston. They are designed to direct a stream, not a spray, at the bottom of the piston crown, not the cylinder walls.

I have no idea if NASCAR teams use them.
PSA
Member
Member
Posts: 69
Joined: Thu Jul 16, 2015 12:57 am
Location:

Re: Piston oil squirters in NASCAR engines

Post by PSA »

It seems like a lot of jets for one cylinder, even the high stressed big bore diesels I've worked on only had one, but it shot the oil through a channel in the piston crown.
The pistons seized in under 20 seconds without them, so they do work.
Calypso
Pro
Pro
Posts: 458
Joined: Mon Oct 17, 2005 1:38 pm
Location:

Re: Piston oil squirters in NASCAR engines

Post by Calypso »

Not really a direct answer as it is Honda F1, but should be relevant:

http://www.f1-forecast.com/pdf/F1-Files ... P2_08e.pdf
hoffman900
HotPass
HotPass
Posts: 3445
Joined: Sat Feb 23, 2013 5:42 pm
Location:

Re: Piston oil squirters in NASCAR engines

Post by hoffman900 »

NASCAR absolutely uses them and I think all engines should use them.

If you scroll to Page 30/108, you can see how Roush-Yates laid out the piston oil squirter oritentation on the RY45 engine (wide bore block that uses the NASCAR FR9 head castings, for Super Outlaws and other applications):
https://www.enginebuildermag.com/2019/0 ... el-engine/

I am not sure if these are single jet stream or not. My guess, is they are multiple streams.

Here is how Honda developed their piston oil squirters in their V8 F1 engine (circa ten years ago):

Development of Reciprocating Parts and Crankshaft in Honda's Third Formula One Era
http://www.f1-forecast.com/pdf/F1-Files ... P2_08e.pdf

Honda's answer to piston cracking, and making the engines last to two race weekends was to go from a 6 hole, to 12, to finally a 24 hole squirter, but settling on a 19 hole unit in race application (with the same volume of oil as the 6 hole).

This set up allow them to reduce piston temperatures by 77*F and to run more ignition advance (allowing them to make more power, and do so reliably.

Furthermore, with the high crankcase vacuums these engines run, in in NASCAR's case, 28inHg, they need them, in conjunction with DLC coated wrist pins, to prevent wrist pin galling.

So they perform two steps:

1) They oil the wrist pin in high vacuum crankcase applications. This allows the designers to run higher vacuum which allows even lower tension rings to seal. The ring to bore interface is the source for the most amount of friction in an engine and increases with rpm. Decreasing this has big implications on power gain
2) They cool the piston considerably. This prevents piston cracking. Furthermore, as outlined in Honda's paper in the ring development section, the oil squirters were so effective, that they did most of the work in removing heat from the piston, thus allowing the rings to be even thinner / smaller for reduced friction and ring flutter (allowing an increase in rpms). Lastly, you can run at a higher state of tune due to their effectiveness in cooling (ie: more ignition advance, etc.).
-Bob
hoffman900
HotPass
HotPass
Posts: 3445
Joined: Sat Feb 23, 2013 5:42 pm
Location:

Re: Piston oil squirters in NASCAR engines

Post by hoffman900 »

Here is a Mike Laws post from 2006:
Mike Laws wrote: Thu Aug 03, 2006 9:33 am
Stevespeed wrote:Mike Laws makes piston oiler kits. Used to be at BLP but I believe he has his own gig going right now. Might try him for info.
Hello Stevespeed:

I'm still here at BLP - Dad (Bo) keeps trying to run me off - but I'm like an old dog and keep finding my way back home! :D

Here is the quick version of our piston squirter story: We designed (and received a patent on) the method of drilling through the main journal bulkhead, into the base of each cylinder in order to send a stream of oil to the bottom of each piston. This was back in 1993/94 when I was approached by a Ford NASCAR Team to help with wrist-pin seizure/failure. (This is when the teams were first getting creative in utilizing crankcase vacuum to reduce oil wrap-up. "Vacuuming" the crankcase is/was definitely beneficial for HP - however it also removed the "oil-fog" that was keeping the wrist pins lubricated.) So we machined a block for the squirters and the problem was immediately solved. Another beneficial byproduct of oiling the underside of the piston dome is that heat is flowed out of the piston (dome). A portion of the intake charge in all IC engines is used to cool the piston - therefore when we cooled the pistons from underneath, we could then reduce the amount of fuel to the combustion chamber. This resulted in increased fuel mileage and also allowed for a more aggressive tune-up; so it was one of those rare "win-win" modifications.

For several years; NASCAR would not allow a separate oil squirter system (plate between the block/oil pan, squirters installed in the pan, etc.) - however they have since rescinded that rule. As another person stated, utilizing the squirters with external plumbing has the advantage of utilizing "cooled" oil to spray onto the pistons.

The piston-squirter kits remain a popular item for us, particularly with supercharged/turbocharged engines and those utilizing crankcase vacuum.

Thanks.

ML
Obviously, nothing as high tech as what Honda was doing in F1 in 2006-2008, and no doubt NASCAR builders have moved onto something a little more advanced.
-Bob
hoffman900
HotPass
HotPass
Posts: 3445
Joined: Sat Feb 23, 2013 5:42 pm
Location:

Re: Piston oil squirters in NASCAR engines

Post by hoffman900 »

Had the wrong link for the Ford RY45. Use this link:
http://www.engineprofessional.com/EPQ1- ... 8f93e3.pdf
Page 30.
-Bob
Krooser
Guru
Guru
Posts: 1857
Joined: Wed Jul 31, 2013 10:14 pm
Location: Tropical Wisconsin

Re: Piston oil squirters in NASCAR engines

Post by Krooser »

Paging WarpSpeed....
Honored to be a member of the Luxemburg Speedway Hall of Fame Class of 2019
Protech Racing
Member
Member
Posts: 81
Joined: Tue Nov 28, 2017 2:51 pm
Location:

Re: Piston oil squirters in NASCAR engines

Post by Protech Racing »

http://www.pagparts.com/images/18T_Piston_Rod.jpg
Does anyone still drill the small end for pointing a little oil at the piston?
Is it a waste of time?
User avatar
Mummert
Expert
Expert
Posts: 692
Joined: Mon Aug 06, 2007 4:24 am
Location: El Cajon CA

Re: Piston oil squirters in NASCAR engines

Post by Mummert »

Wrist pin oil 100% mandatory, especially with smaller diameters and high vacuum.
Mummert Machine and Development 4 stroke hp
Mummert Y-blocks
BILL-C
Expert
Expert
Posts: 746
Joined: Thu Feb 07, 2008 9:57 pm
Location: Oakville, CT
Contact:

Re: Piston oil squirters in NASCAR engines

Post by BILL-C »

I have the BLP kits for SB Ford, SB Chevy , and BBChevy. We install the squirters on all almost all dry sump builds. All of the NASCAR Cup, Craftsman truck, and ARCA engines we have rebuilt in the last 15 years have had at least one (usually 2) piston oiler jets aimed at each piston. Some jets were built into oil pan, and some built into block.
Carlquist Competition Engines
hoffman900
HotPass
HotPass
Posts: 3445
Joined: Sat Feb 23, 2013 5:42 pm
Location:

Re: Piston oil squirters in NASCAR engines

Post by hoffman900 »

BILL-C wrote: Tue May 05, 2020 8:24 pm I have the BLP kits for SB Ford, SB Chevy , and BBChevy. We install the squirters on all almost all dry sump builds. All of the NASCAR Cup, Craftsman truck, and ARCA engines we have rebuilt in the last 15 years have had at least one (usually 2) piston oiler jets aimed at each piston. Some jets were built into oil pan, and some built into block.
Bill,

Are they both on the exhaust side?

Some of the production Sportbikes are using 6 jets (well, 6 orfices, one jet), but they also have a lot shorter strokes, so they don't as high to shoot,
-Bob
User avatar
4sfed
Pro
Pro
Posts: 338
Joined: Sun Mar 13, 2011 11:32 pm
Location:

Re: Piston oil squirters in NASCAR engines

Post by 4sfed »

From this paper ...
http://www.f1-forecast.com/pdf/F1-Files ... P2_08e.pdf

"the flow rate oil injected was slightly higher than 10 l/mim"

That's a lot of oil.
stealth
Guru
Guru
Posts: 1391
Joined: Fri Jun 30, 2006 9:37 am
Location:

Re: Piston oil squirters in NASCAR engines

Post by stealth »

Nascar Squirters listed on eBay.
You do not have the required permissions to view the files attached to this post.
Post Reply