The 97 CV "Tank of Justice III" (TOJ3)

[gadget73]

Is there a way to hack the stock gauge to work properly, or do you just mean its a dummy gauge because its got no numbers? I know they were making oil pressure gauges that were basically an idiot light for a while. It was exactly mid-scale at all times unless you had no oil pressure. F that.

[Giraffe]

I came across this a few years back with the intention of doing this on my 1995 Cobra. haven't got around to it, but it's something I would still like to look into. I never have cared for pillar gauge pods. This focuses on Mustang clusters, but may be applicable to a panther within the same model years.

https://accutach.com/

https://websites.godaddy.com/blob/19...9.pdf?c6f09509

[SVT98t]

Well, made it to Indiana, 506 miles on one tank, so far. I'm gonna run it empty to see how far I can go.
The low fuel light came on at 485.3 miles, lol. I estimate it running out at 533 miles.
This thing needs 2.73s, and lower grill block and chin spoiler and will be ready for 600 miles/ 30mpg.


-ryan s.

Sent from my SM-J727P using Tapatalk

[Tiggie]

I came across this a few years back with the intention of doing this on my 1995 Cobra. haven't got around to it, but it's something I would still like to look into. I never have cared for pillar gauge pods. This focuses on Mustang clusters, but may be applicable to a panther within the same model years.

https://accutach.com/

https://websites.godaddy.com/blob/19...9.pdf?c6f09509

Interesting stuff.
I have seen people just swap the sensor to a sender, and short the resistor where applicable. I wasn’t impressed with the results as the oil pressure gauge was a bit jumpy and did not inspire confidence. Will look into this option.

[SVT98t]

Still going at 541 miles...


-ryan s.

Sent from my SM-J727P using Tapatalk

[sly]

I have 2.73 gears in box, ready to ship if you don't already have them. Though you can probably get them for less locally than just the shipping cost from me.

[DerekTheGreat]

541+ miles on a single tank is incredible. I think you should keep the ratio you've got. I've heard taller rear gears kill city MPG and 2.73's might not make it much happier on the freeway.

[SVT98t]

I already have a set from TOJ2. Thanks though.

Derek, he's where I can prove why the change to 2.73s would be better.
I noted on the drive here, that at 60mph, I was rolling about 1950 rpm. Not too bad. The 2.73s I had in TOJ2, I was rolling at maybe 1500 rpm. Let's call it a 400 rpm difference between the 3.27s, and the 2.73s. So that's 400 more ignition cycles, which in turn means the injectors are fired 400 more times a minute. Just extended that to an hour, and the engine would have fired and additional 24,000 times. That's some hefty fuel savings if you ask me. I still want to get an exact number on fuel dispensed per rotation, so I can get an actual number for amount of fuel saved over a minute, and an hour, just to start.
I live in the country, the speed limit on my road is 55mph, and I live in the middle of a 4 mile straightaway. I rarely do city driving, plus I am building this car and an efficiency project. I have a 16 mile commute to work. There's 3 traffic lights and 5 stop signs. 2.73s will work fine.

I'd say my next goal now is to hit 600 miles on a tank, which doesn't seem as difficult as I previously thought. The difficult part isn't "pulling 29 mpg on my 200 mile road trip" like most people seem to do. The difficult part is averaging 29 mpg over the entire tank of gasoline. Which I'm at between 27.5-28.5mpg currently.


-ryan s.

[jaywish]

Fuel dispensed is a variable amount. IIRC it is expressed as a percent. So at a given demand, as computed by the tables in the main computer, it will remain open for say 10% or 20% of the time. At 100% is how the maximum flow rate is calculated, say a 14lb or 19lb injector. It will not be a straight correlation with RPM. The idea generally being to use the minimum amount necessary to cruise at a given speed while not producing too lean of a condition.

So a lower Engine RPM at a given constant speed will generally reduce the fuel requirement by the power needed to spin the motor, accessories, transmission components and driveshaft for the number of RPM saved. So for a rough illustration, if you were 300RPM lower then how much fuel would it take to spin everything with no load at 300 RPM? The drag of the vehicle, and the fuel required for that, will remain constant. There of course are other variables with a camshaft controlling the valve lift and duration as optimization compromises must be made.

[kishy]

I have one of those HFT "Nitrous" tachs in my 91 in a pillar pod. After a couple years the needle developed a tendency to stick at 0 and require a gentle whack against the pillar pod to unstick. Something to watch out for, and may not affect them all equally.

The same has happened to the actual speedometer in that car, and the mechanical temperature gauge in my Town Car, so I'm assuming there's a spot that needs lubrication in them to fix it.

[DerekTheGreat]

In theory it sounds right that you should save fuel buuut my limited mathematics and physics skills taught me that gear ratios also multiply power and that you want to keep the engine near where it's making peak torque or an acceptable amount. So, 3.27 to 2.73 means a ~17% reduction in available torque at a given RPM, which of course was already cut by whatever your OD ratio is.. Imagine a bicycle, just because your legs are moving slower doesn't mean you're burning less calories/exerting less effort, right? Same thing with a car, so while your RPM will be lower, and the ignition & injector cycles less its like Jay said, those injectors will be open longer and squirting more fuel in to compensate for the load. I like to look at manifold vacuum to determine how good my fuel economy is for a given condition, especially with my manual trans stuff, helps me select the ideal gear instead of which one my head thinks is best. Also, on that note: My first stickshift vehicle was a '94 Ranger, and I had the mindset that lower RPM at any speed = more MPG. So I'd throw that thing in OD at 35 or even 40 mph. It has 3.73's and an M5ODR1.. My first two tanks were TERRIBLE, like 15 mpg. I began the practice of leaving it in 4th unless I was going 45 or higher and mpg's shot right up in the 20's despite it revving around 2k or whatever the hell the thing said. If I got my mathematicals wrong, please someone straighten out my ignorance, I don't mean to go spewing misinformation everywhere.

[sly]

Well... my 93 used to get 26-28 mpg on trips (flat land mind you) loaded with the 2.73 gears and can't best 21mpg any more with the 3.55 gears and PI swap. Speeds are generally the same too... around 70mph. Now, this is true for aeros like mine and Ryan's. Boxes are a very different beast due to the rolling brick aerodynamics. At 55-60mph, it's not so bad, but up at 70+, it really starts to drop.

[SVT98t]

Fuel dispensed is a variable amount. IIRC it is expressed as a percent. So at a given demand, as computed by the tables in the main computer, it will remain open for say 10% or 20% of the time. At 100% is how the maximum flow rate is calculated, say a 14lb or 19lb injector. It will not be a straight correlation with RPM. The idea generally being to use the minimum amount necessary to cruise at a given speed while not producing too lean of a condition.

This is where the vacuum gauge comes in.
It's been an amazing asset to hypermiling. I'm trying my hardest to keep as much vacuum as possible, since my fuel pressure regulator is vacuum driven (ie my right foot).
Typically, I try to stay around 60-65 mph. If i'm loafing along, I'm generally in the range of 16-20 inches of mercury. At idle, in park, it's close to 25. Moderate throttle yields around 10 or less inches. That's where you loooooooose fuel economy.
I'm in Indiana for the week. I don't have to work this weekend, and I don't start class until Monday (Online). I'll be researching the crap out of this stuff even more this weekend.

As compared to Sly's Vic, I also have a PI swapped car, but it has the aluminum block, and no tune. And with respect to TOJ2, TOJ3 is 200 lbs lighter. So there's even more weight-savings there.

I want to keep this conversation going. It's very interesting and I like getting input from everyone. Thanks mangs.


-ryan s.

[sly]

Front/rear skid plates would also help as it would add some aero as well.

[sxcpotatoes]

I've seen hypermilers put rope caulk around their headlight housings to fill in gaps to reduce that much more drag. What about a semi truck/trailer style wind-actuated tail flaps to increase aero?