Camaro XV

[Stielow]

Originally Posted by mikels

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

Yes the Mule made more dyno power. I did drive it at Thunderhill at 8 psi boost and it ran great until the oil temperature was too high. We never ran it at full boost on track. Even with very well sized turbos the turbo lag and power boost is harder to drive off the corners than the 427 SC engines. I think the installed power of Mayhem is on pair with where the Mule is on pump fuel. But, the 427 SC LS engines that Dave has tuned have great driveablty. They are like big electric DC motor. Demand torque and get torque. The engine calibration is dead on, no holes or sags. The Mule had an old FAST EFI system on it off memory and had a good cal but not a refined as the LS stuff.

I love the big inch blown LS9 based engine. I finally have great street drivabilty that makes stupid power. Both Red Devil and Mayhem’s engine idle below 800 rpm and have OEM drivability. I also love the fact I can beat them hard on the track with no issues if you can keep them cool and fed with fuel.
Mayhem makes more power more efficiently than Red Devil due to better management of air through the engine. We made more power with less boost. By working the blower less hard it makes less heat and takes less power to turn. We are now running it at a more efficient point on the compressor map. Huh… Engineering…

Mark

[clill]

Yes I'll sell anything including the Mule. You will even get cases of Stielow books. I'll even make him autograph them . The Mule was built with 8 stack Kinsler injection but was supposed to be a twin turbo while mark still owned it. The problem was the Turbo engine builder was so slow Mark ended up selling me the car before he got the engine. When he finally got the engine it went in Malitude. Then under Jody's ownership Malitude got a better twin turbo engine. The Mule still has the Kinsler intake on it under all that hand fabbed aluminum.

[Stielow]

Originally Posted by clill

Yes I'll sell anything including the Mule. You will even get cases of Stielow books. I'll even make him autograph them . The Mule was built with 8 stack Kinsler injection but was supposed to be a twin turbo while mark still owned it. The problem was the Turbo engine builder was so slow Mark ended up selling me the car before he got the engine. When he finally got the engine it went in Malitude. Then under Jody's ownership Malitude got a better twin turbo engine. The Mule still has the Kinsler intake on it under all that hand fabbed aluminum.

The Mule runs like a freight train also. If I took what I have learned over the last 5 - 7 years and tuned on the Mule it would be faster yet. Still a great iconic car. At the time I did the Mule I did not size the oil cooler big enough.

Mark

[GregWeld]

What a great discussion!


Let's face it -- it's just hard to beat great engineering!

[camcojb]

Originally Posted by Stielow

The Mule runs like a freight train also. If I took what I have learned over the last 5 - 7 years and tuned on the Mule it would be faster yet. Still a great iconic car. At the time I did the Mule I did not size the oil cooler big enough.



Mark

[Stielow]

Originally Posted by camcojb

That's Jody in a the passenger seat....

Fun day beating on Charley's junk.

Mark

[Steve68]

Mark,

whats the difference in oil cooler sizes between the Mule and Mayhem vs XV, is it a difference in line size or cooler size, thanks

[Stielow]

Originally Posted by Steve68

Mark,

whats the difference in oil cooler sizes between the Mule and Mayhem vs XV, is it a difference in line size or cooler size, thanks

The Mule had a oil to water oil cooler built into the end tank of a Griffin rad. It held the oil temp down to under 250F for 3-5 laps. The turbos drive a lot of heat into the oil. One issue I have found is some of the older gauges don’t read high enough for synthetic oils. Redline has told me there engine oils are good to 325F. The Mule gauge pegged at 250F so we were shutting off early. Jackass has a relatively stock LS9 in it and it has no cooling issues on track with its Ron Davis rad with an oil to water oil cooler built into it. Red Devil runs a stock LS9 oil to water oil cooler mounted to the side of the engine. Once we had that car fully tuned up it would over temp the oil and the water in 5 laps on a 90 degree day. On Mayhem I upped the rad and moved the trans and diff coolers to the back of the car. In a 5 lap session the water temp was great and the oil temp is getting marginal. That oil cooler is built into the rad as a oil to water cooler.

On Camaro XV we upper the rad size even more with a custom core from Dewitt. I met with C&R rad at SEMA and they steered me to a larger 13 plate oil to water oil cooler that should keep my oil temp good. I have opened up the front of the car with the new Anvil front clip. I’m using my vented hood again to help move air through the rad. Dewitt is also making me a one off intercooler heat exchanger that will nest into the cooling stack to maximize core face and air flow. On Red Devil, Mayhem and Camaro XV I’ve ran a very large powerful cooling fan. It is a 20 inch dia Caddy SRX Turbo fan what pulls 850W. I like oil to water coolers because it heat the oil then cools the oil. It also makes a very clean installation. Dewitt is finishing the cooling stack next week and I hope to have some photos to post.

On a side note the LS9 based engines have oil squirters that shoot oil on the bottom of the piston to cool the pistons. Thomson modifies the LS7 block to add the piston squirters. He did a lot of testing to sort out the size and the location of these squirters. This does drive oil temp. Also as the power goes up so do the heat rejection requirements.

On your question on oil line sizes. I’ve been running -10 AN for cooling lines. I have run 12 AN but the 10 AN seems fine. I don’t have the sizes of all of the different coolers, sometimes it is hard to get the heat rejection rates or to know what you need without just testing it.

Hope that helps

Mark

[Gandalf]

Hey Mark, et all; thanks for the awesome detailed info on topics that inevitably come up for many of us both during and after an initial build. It's great to have good, experienced, first-hand, engineering-driven info like this. I really hope you have time to capture some of this for your next book :-)

G.

[ironworks]

It is amazing how much more complicated this get with every extra horsepower. All the heat you have to deal with is amazing.

When I helped out on a Turbo drag car that was running high 6 second passes. We would put 40 lbs of ice in an aluminum 20 gallon fuel cell and water to air intercooler and in one 1/4 mile pass you would have luke warm bath water. 4 10lbs bags of ice in a quarter mile.

That just goes to show how much work building a big Hp road race car is and why most big race teams don't run huge power.

Thanks for the insight Mark, I feel like I can go home for the day after I learned something.