Where is everyone #5

Great minds think alike...…...evidently ours do as well!

 

Cash box on 88, 130 mi n we be home baby

 

I have unexpected news coming from the location that I woke up horizontal. But first food and coffee.

 

Stolen to be tested tomorrow

 

This. I built a hotrod dt466 for my toter truck when i began moving my machine shop. With no CDL i was limited to 26k but typically had up to 32 on there with fingers crossed. That truck would pass cars doing 70mph up hazleton or port jervis.. Until boom. Twice it blew brand new headgaskets and the radiator cap couldnt vent 3000rpms of swept volume fast enough so the aluminum fabricated degas tank id built would balloon until the seam split the weld.

Ive thrown grenades. The sound was similar and coolant would blank out the windshield each time. 35psi kept lifting the headstuds. One instance was 4 days no heat in a parking lot alone and sick on thanksgiving, and a few mile walk for coolant and oil. I keep a spare HG in it and crest those same hills at 35mph and half throttle now. Slow is faster than scattered.

The more power you want to make [by pouring fuel] the more CFM youre charger needs to provide, or EGT will make it unuseable on the long hills. You have to think of fuel as the devil and boost flow, not necessarily pressure, as the savior. Boost is sort of like air conditioning inside a cylinder. Change nothing but smaller charger CFM and your EGT will rise. If youre stacks are coaling at all beyond idle you want more conpressor CFM to cover that excess fuel.

I used a very small turbine housing and a comparably large compressor and logged boost to drive pressure all the time on huge mechanical gauges and it was 1:1. No "choking" issues, thats a wives tail. This thing always had exactly as much boost as it did drive pressure.. And sometimes up to 1 or 2psi more boost than drive. It was sized perfect. This was a 7.6L breathing thru a smallish T3 turbine with a 60ish mm compressor if i remember right.. It was a turbo i remanned off a junkyard C7 and the sizing is the opposite of internationals huge turbine tiny compressor strategy, which results in very lackluster performance.

Anyhow high egt is the enemy but boost is the cure. I know thats unconventional wisdom but you can go test it yourself.

With coolant temps, if there are no changes to power output then a hotter gauge reading probably indicates a more efficient thermal transfer of BTU's off the cast iron and into the coolant. The first row of liquid molecules touching cast iron is called boundary layer. Whether its gas molecules or liquid molecules.. So boundary layer matters in head porting or in block cooling or in oil pumping. Its all flow. Boundary layer molecules stick to the iron or aluminum with a force most call "static tension" and dont want to move. The next row of molecules has static tension to that row and so on and so forth. Pulling these molecules from each other requires breaking this static tension.. Usually called "shear." The further you get from the wall the higher the rate of molecules passing by simply because they have less tension in need of a sheering force [suction, pressure, wind, gravity, etc] to move them. The middle of a port always has the highest flow velocity. So does the middle of a river. If you get a stick and go scratch out drainage channels at a construction site youll see all these things in the mud swirls. Your laminar and turbulent flows, boundary layer friction and high flow rates away from the banks with muddy shearing streaks near the slow moving flows at the wall.

Anyhow.. That lays the groundwork for this next part. Increased cooling efficiency without changing metals is done by changing liquids. Using a liquid with less static tension allows the boundary layer to shear easier and thus flow faster, carrying away the thermal load at a faster rate. Measured at the cylinder temps will be lower, measured in the radiator, higher.. Because we are simply transfering the energy through conduits using a liquid media.. The coolant. "Water wetter" is a product sold to increase cooling capacity, and its essential soap. A drop of dawn will do the same, itll lower the static tension of the boundary layer. That is what surfectants do. "Cutting grease" is lowering the grease or fat molecules ability to bond to itself and smear around when you scrub. If your block is full of rust and sludge, thats another issue, its an insulator.

All that said, an engines heat is its power and it goes 3 places. Out the exhaust to the atmosphere, into the water jacket to be carried away by the coolant and dispersed to the atmosphere, and into the chamber space, which creates the pressure rise that drives the rod down into the crank. Heat makes torque. The less you lose to your coolant and your exhaust, the more you reserve to do meaningful work in the crankshaft. Too much and too little are both issues.

 

That's good!

 

I hope you enjoy it!