ArdWrknTrk Posted September 9 Share Posted September 9 190° is the thermostat temperature, it better be getting a lot cooler than that if it's going to have any ∆ to carry away heat as it goes past the cylinders to the back of the block and then forward through the heads to the thermostat (and bypass) before entering the radiator. Cooler is not better when the viscosity needs to be constant. The forward pump needs to make constant pressure, the torque converter wants a constant viscosity so the truck beheaves the same at all times, the passages/bands/clutches are engineered to be a certain operating temperature. We had the Ford power train engineer who designed the E4OD (and whose father developed the C4&6) back at FTE. I believe his name is Mark Kovalosky??? Cool dude and very engaged when questions came up. 👍 This is not dissimilar to Ford tuning carburetors for 105°F. Cooler air can make more power, but you can't keep the environment at 20° all the time, so you shoot for something reasonable, use the CWM to draw warm air off the exhaust manifold or cool air through the radiator support and call that the baseline. Sure, you may have days above 105, but unless you live in Death Valley those are outliers. The same with component clearances. Cam & crank bearings, rod journals and piston clearances are all cold measurements that should end up optimal at operating temperature. That aluminum piston is going to expand a whole lot more than the cast iron bore it runs in.... 💡 Link to comment Share on other sites More sharing options...
Gary Lewis Posted September 9 Share Posted September 9 This is not dissimilar to Ford tuning carburetors for 105°F. Cooler air can make more power, but you can't keep the environment at 20° all the time, so you shoot for something reasonable, use the CWM to draw warm air off the exhaust manifold or cool air through the radiator support and call that the baseline. Sure, you may have days above 105, but unless you live in Death Valley those are outliers. The same with component clearances. Cam & crank bearings, rod journals and piston clearances are all cold measurements that should end up optimal at operating temperature. That aluminum piston is going to expand a whole lot more than the cast iron bore it runs in.... 💡 You beat me to it, Jim. The tranny is much like the carb - tuned to a temp. Any temp variation above or below changes things. So you put the aux cooler ahead of the radiator, which operates at a relatively constant temp, and that means the tranny sees a relatively constant temp. Link to comment Share on other sites More sharing options...
viven44 Posted September 9 Author Share Posted September 9 You beat me to it, Jim. The tranny is much like the carb - tuned to a temp. Any temp variation above or below changes things. So you put the aux cooler ahead of the radiator, which operates at a relatively constant temp, and that means the tranny sees a relatively constant temp. All this makes sense... but I followed what was done from factory (BB 2WD, parts truck). The line from the Aux cooler runs to the transmission return (rear port on C6 -- assumed to be return). Front port of the C6 (Closer to the torque converter) runs to the radiator. Link to comment Share on other sites More sharing options...
85lebaront2 Posted September 9 Share Posted September 9 All this makes sense... but I followed what was done from factory (BB 2WD, parts truck). The line from the Aux cooler runs to the transmission return (rear port on C6 -- assumed to be return). Front port of the C6 (Closer to the torque converter) runs to the radiator. You are correct, the return is directed to internal lubrication on a C6 (and most other automatics). Link to comment Share on other sites More sharing options...
viven44 Posted September 10 Author Share Posted September 10 You are correct, the return is directed to internal lubrication on a C6 (and most other automatics). Thanks Bill for the confirmation... About the long distance trip on Friday.. the day is going to be hot. Mid-90s. Too hot perhaps to be driving BB 2WD.. About the transmission, the moment the 1st gear went away is when I gunned it at the stop light trying to race this VW GTI I don't know if I caused the governor to get stuck doing that ??? As long as I drive it carefully I have no doubts the Bronco would do just fine.... . Also, the 3.5 gearing on Bronco vs 3.0 gearing on BB 2WD makes a big difference on highway cruising ease. About 2200-2300 rpm is where I like to be on the highway. On Bronco thats roughly 60mph, on BB 2WD, thats close to 70 mph.. Plus I'll be honest, the bullnose trucks just drive better than the dentside... hands down.. Air conditioning vs highway cruising ease... hmm... I've been debating. Link to comment Share on other sites More sharing options...
85lebaront2 Posted September 10 Share Posted September 10 Thanks Bill for the confirmation... About the long distance trip on Friday.. the day is going to be hot. Mid-90s. Too hot perhaps to be driving BB 2WD.. About the transmission, the moment the 1st gear went away is when I gunned it at the stop light trying to race this VW GTI I don't know if I caused the governor to get stuck doing that ??? As long as I drive it carefully I have no doubts the Bronco would do just fine.... . Also, the 3.5 gearing on Bronco vs 3.0 gearing on BB 2WD makes a big difference on highway cruising ease. About 2200-2300 rpm is where I like to be on the highway. On Bronco thats roughly 60mph, on BB 2WD, thats close to 70 mph.. Plus I'll be honest, the bullnose trucks just drive better than the dentside... hands down.. Air conditioning vs highway cruising ease... hmm... I've been debating. Now you know why I went MAF/SEFI on Darth and am using an E4OD. 60 mph is right around 1600 rpm, used to be 2200 with the C6. Even with the low compression due to carbureted short block and early EFI heads, he still got 12.5 mpg on a mostly 70 mph run from the Eastern Shore to Falling Waters West Virginia. Darth weighs 6400 lbs empty, add 225 lbs for me and starting with 38 gals of regular gas so add 235.6 lbs so figure 6861 rounded to the nearest lb and I am turning 6 tires (or tyres if you prefer the British spelling). Link to comment Share on other sites More sharing options...
viven44 Posted September 10 Author Share Posted September 10 Now you know why I went MAF/SEFI on Darth and am using an E4OD. 60 mph is right around 1600 rpm, used to be 2200 with the C6. Even with the low compression due to carbureted short block and early EFI heads, he still got 12.5 mpg on a mostly 70 mph run from the Eastern Shore to Falling Waters West Virginia. Darth weighs 6400 lbs empty, add 225 lbs for me and starting with 38 gals of regular gas so add 235.6 lbs so figure 6861 rounded to the nearest lb and I am turning 6 tires (or tyres if you prefer the British spelling). That sounds about right Bill.. The Bronco weights about 5600 lbs with me in it and full tank of gas. The other day on my ~200 mile trip I averaged 9.5mpg, doing ~60-65 the entire time. I have always wondered what the relationship between MPG and MPH is at cruising speeds. Clearly the RPM is higher for a higher speed, but you are also traveling further .... but I'm sure that tails off above a certain RPM (due to?)... I'm sure there is an optimal speed for every vehicle where it is most efficient. I don't know if there is an easy way to determine that.... Link to comment Share on other sites More sharing options...
Gary Lewis Posted September 10 Share Posted September 10 That sounds about right Bill.. The Bronco weights about 5600 lbs with me in it and full tank of gas. The other day on my ~200 mile trip I averaged 9.5mpg, doing ~60-65 the entire time. I have always wondered what the relationship between MPG and MPH is at cruising speeds. Clearly the RPM is higher for a higher speed, but you are also traveling further .... but I'm sure that tails off above a certain RPM (due to?)... I'm sure there is an optimal speed for every vehicle where it is most efficient. I don't know if there is an easy way to determine that.... Wind resistance goes up with the square of the speed. And while Ford says they spent a lot of time in the wind tunnel for these trucks they must not have used what they learned on them. The recessed headlights, grille, etc are worse than a barn door. 9.5 MPG isn’t bad but it isn’t good either. The C6 is a big part of the poor economy. As Jim says, it is one of the world’s best at turning energy into heat. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted September 10 Share Posted September 10 That sounds about right Bill.. The Bronco weights about 5600 lbs with me in it and full tank of gas. The other day on my ~200 mile trip I averaged 9.5mpg, doing ~60-65 the entire time. I have always wondered what the relationship between MPG and MPH is at cruising speeds. Clearly the RPM is higher for a higher speed, but you are also traveling further .... but I'm sure that tails off above a certain RPM (due to?)... I'm sure there is an optimal speed for every vehicle where it is most efficient. I don't know if there is an easy way to determine that.... You're driving up to Skiatook on Friday? How far is it? Link to comment Share on other sites More sharing options...
viven44 Posted September 10 Author Share Posted September 10 You're driving up to Skiatook on Friday? How far is it? It is about 270 miles... Link to comment Share on other sites More sharing options...
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