Camaro XV

[kwhizz]

When you are making Stielow power.......Just think about the pressure transferred between the teeth on the pinion and the ring gear under full throttle......tremendous pressure equals Lots "O" Heat........and that go's for everything else in the system...........

Ken

[BADcarma]

I have been thinking about heat management in my project as well. I looked at the Corvette racing team's cars and observed that the rear bumper covers are vented and visible through the screen is what looks like an AC condenser and fan, the possibility that other heat exchangers are tucked in there is pretty good. I've not been under a 69 Camaro but I have seen some custom work on the lower valances on many cars. Usually it's for exhaust tips but I was thinking that maybe there is enough room to mount heat exchangers there and vent them through the valance. This will package and work well for my car but it certainly won't work for a lot of vehicles.

[Vince@Meanstreets]

Originally Posted by Track Junky

I'm running an NA 427 620/560 to the crank and my KRC aluminum PS pump has treated me well so far since 2002. My trans is spec'd for Royal Purple by the builder and I change fluids after every track day and the oil still looks good. Trans in car since 2006. No cooler for rear diff either and car is used strictly for time trials on road courses. Same Eaton carrier since 2004.
This is why I asked the question.

says the guy that "boiled" the top off of his power steering pump on a track day.

[CarlC]

Originally Posted by Vince@MSperfab

says the guy that "boiled" the top off of his power steering pump on a track day.

Been there, done that.

Mark, are you running thermostats on the drivetrain coolers (differential + transmission) combined with differential gear oil squirters?

Any concerns with EHL film thickness on the engine bearings running 1000+ piston horsepower?

[mikels]

Originally Posted by CarlC

Any concerns with EHL film thickness on the engine bearings running 1000+ piston horsepower?

First Thomson 427SC engine was built and run way back in 2008. This was for his Pontiac Solstice and utilized LSX block, LS7 heads and Harrop 2300SC. Engine made 990+ crank HP with an aggressive cam, and dropped to 850 crank HP with milder cam as installed in car. After over 100 dyno pulls and 5000+ miles installed in car, engine was disassembled and all parts blueprinted / inspected for wear. All looked great. Keep in mind this was never used for road-race or extended high duty cycle use, so powertrain cooling was never an issue.

At same time this was ongoing, Thomson was developing a twin-turbo LSX generating 2000+ HP. Original engine was 440 CID and dyno testing reveled that after few pulls, crank bearings were distressed, and had they not been coated bearings, a bearing failure would have been likely. Issue was traced to crank deflection under load, so stroke was shortened (increased overlap of throws and mains) to increase strength. Engine then completed 150 full power pulls on dyno (2058 HP average) and subsequently disassembled. All bearings looked like new.

Fast-forward to today:

Based on these and countless other engine builds, testing and further development, Thomson 427SC engines have proven themselves robust even under extreme racing type usage (Mark's cars being one of the most aggressive test beds used). We continually refine and improve package based on knowledge gained over each build and test data. This includes not only hardware selection, but assembly clearances, powertrain cooling requirements and calibration refinement.

Mark has said on many occasions that not only are the Thomson 427SC engines the most powerful he has ever utilized in his builds, they have also been the most reliable and driveable as well. And hard to dispute the results.

Not sure if this directly answers your question as we lack the technology to measure oil film thickness, but empirical data based on many, many engines supports where we are today (with headroom to grow ).

[RussMurco]

Originally Posted by mikels

First Thomson 427SC engine was built and run way back in 2008. This was for his Pontiac Solstice and utilized LSX block, LS7 heads and Harrop 2300SC. Engine made 990+ crank HP with an aggressive cam, and dropped to 850 crank HP with milder cam as installed in car. After over 100 dyno pulls and 5000+ miles installed in car, engine was disassembled and all parts blueprinted / inspected for wear. All looked great. Keep in mind this was never used for road-race or extended high duty cycle use, so powertrain cooling was never an issue.

At same time this was ongoing, Thomson was developing a twin-turbo LSX generating 2000+ HP. Original engine was 440 CID and dyno testing reveled that after few pulls, crank bearings were distressed, and had they not been coated bearings, a bearing failure would have been likely. Issue was traced to crank deflection under load, so stroke was shortened (increased overlap of throws and mains) to increase strength. Engine then completed 150 full power pulls on dyno (2058 HP average) and subsequently disassembled. All bearings looked like new.

Fast-forward to today:

Based on these and countless other engine builds, testing and further development, Thomson 427SC engines have proven themselves robust even under extreme racing type usage (Mark's cars being one of the most aggressive test beds used). We continually refine and improve package based on knowledge gained over each build and test data. This includes not only hardware selection, but assembly clearances, powertrain cooling requirements and calibration refinement.

Mark has said on many occasions that not only are the Thomson 427SC engines the most powerful he has ever utilized in his builds, they have also been the most reliable and driveable as well. And hard to dispute the results.

Not sure if this directly answers your question as we lack the technology to measure oil film thickness, but empirical data based on many, many engines supports where we are today (with headroom to grow ).

And...

Originally Posted by mikels

In this case, there is 3 sources of heat - engine, supercharger and AC. Breaking that down further, engine heat in form of coolant and oil, supercharger heat in form of air and AC in form of refrigerant.

Engine heat in coolant and oil comes from the inefficiencies of an IC engine - only about 1/3 the energy released from combustion actually makes power, another 1/3 goes into cooling system (coolant & oil) and 1/3 goes out exhaust.

Since this is a SC engine, also have to take into account mechanical energy used to drive supercharger - in Red Devil and Mayhem, this worked out to ~120-140HP. So Mayhem generating an output of 878 HP is actually generating over 1000 HP already - and that also nearly equals the amount of energy we need to release from cooling system.

Complicating this further, we have the heat from the intake air charge to reduce as well - and use air-to-water heat exchanger with a stand-alone cooling system to then convert this with a water-to-air heat exchanger in front of car. Since delta-T is critical for heat exchanger effectiveness, we package the intercooler radiator in front of the cooling stack (all the heat exchangers in front of car) to get greatest delta-T for charge air cooling. This adversely effects radiator efficiency as air temp reaching front face of it is already heated above ambient. And we have 1000+ HP worth of heat to dissipate from it.

Packaged between the CAC (charge air cooler radiator) and the coolant radiator is the AC condenser. At least Mark hasn't become too much of a wimp is his old age to want to race with AC on, so while this doesn't add heat to air flowing through, it does add pressure drop of airflow through entire cooling stack.

We also have engine oil to contend with - and can either use oil-to-air heat exchanger, or oil-to-water. If oil-to-water, this is more KW to release through radiator. If oil-to-air packaging, airflow restriction and preheated cooling air have to be considered.

All this is converted to heat transfer equations and calculated to optimize the entire cooling system of heat rejection balance.

Drag racing is easy - you can get away with a whole lot if only running in <10 second bursts of WOT. Road racing makes this much more difficult as entire system reaches equilibrium.

And haven't even talked about trans and diff oil cooling yet....

Dave

Wow... This is above and beyond the most informative, real-world experience information I have ever read on a forum of any kind. On occasion I think I have most all the knowledge I need to accomplish a goal, then I get slapped into reality with posts like these and it makes me thirsty for more information.

I am so grateful that you guys share this information with us, I learn something every day on this site. Being a "fly on the wall" has never been so interesting!

Thanks!!!

[Rybar]

Originally Posted by mikels

Mark has said on many occasions that not only are the Thomson 427SC engines the most powerful he has ever utilized in his builds, they have also been the most reliable and driveable as well. And hard to dispute the results.

Interesting. So Mayhem's motor is more powerful than the Mule's TT SBC? I always wondered what Mark's thoughts were on comparing his latest cars to the Mule. That thing was so far ahead of it's game when he built it. Love that car I hope Charley never sells it.

[GregWeld]

Charley will no doubt whip me like a small child -- but if I remember correctly -- the Mule was not a TT build when Mark did the car... it was an 8 stack injected small block... and CHARLEY converted it to the TT configuration that I think made 1041 HP....

[Rybar]

Originally Posted by GregWeld

Charley will no doubt whip me like a small child -- but if I remember correctly -- the Mule was not a TT build when Mark did the car... it was an 8 stack injected small block... and CHARLEY converted it to the TT configuration that I think made 1041 HP....

I think you are right Greg.

[mikels]

Originally Posted by Rybar

So Mayhem's motor is more powerful than the Mule's TT SBC?

While the Mule is certainly capable of making more power than Mayhem, I don't believe it has ever been run in 'track duty' at a power level higher than Mayhem due to the very thing we were talking about previously - powertrain cooling.

Dave