So this isn't as fun to answer as when someone asks where to shift for power. But I was wondering what people usually purr at and what kinda mileage they get, with the 5.0L. Not sure there can be much difference between the EFI and Carb. but like to hear from both sides. I know my car is not running perfect yet... But i get horrible mileage. I've got a T5 with 2.79 gears... hi i know.. but I would think the higher gears would help with the mileage... I've tried sticking around 1,500 and tried stickin around 2,000 which seems really high to me specially with a V8.
2K is nothing for a V-8. If you are carbed and useing the OD below 1900 to 2100 rpm. You are running on the idle circuit of the carb. This means running rich and lousey mileage. If you stay out of the OD...Your mileage may improve. If its injected...You need to get it running/working properly (same if its carbed) You may have to get the pcm programmed to give you proper fuel trim with the 2.79s' at lower rpm. Shifting for mileage means upshifting without revving the engine to the top of the gear (winds out) but not shifting so low down in the rpm that the engine lugs in the next gear. Each car is different, you will have to feel it out to find the balance between when to shift vs speed at time of shift vs rpm...Good luck!!!
so you've noticed that 2 is best? I guess I'm over thining. That's what my four cyclinder peicer was when i was cruising... so it made sense i was using twice the gas with an 8... anyway. I'll give her a go. And trust me. reprogram is right after the MAF conversion. Then let it chill for a bit before really going to town...
My mavs average 20 to 23 mpg at 2400 rpm. With current gear ratios/tire sizes this workes out to 66 to 70 mph, one is a 3spd stick with 3.23:1 the other is an aod with 3.80:1...Both cars carbed. Whats best will be where the engine is doing the least amount of work to maintain a certain speed/rpm. This brings cam specs/ cyl head efficiency/ ignition timeing and the like into the equation. When working properly, in stock trim your injected 302 should pull down between 15 and 18 mpg with a cruise mileage of somewhere between 19 to 22 mpg.Good luck!!!
Yeah... Normally there's a nice period of time when you get a car, when you stick out the bad mileage(can afford it) to find the sweet spot... I can't afford 8 mile driver to find the sweet spot, was looking for some direction. So thanks! I thought right on top of torque curve was best... which i thought was right at 1,500 so maybe i'm wrong in one or both counts....
First, I think the 2:79 gears are part of your problem. Those gears would be find for setting land speed records at Bonneville, but for every day driving............unless you get on a freeway right from your house and cruise at a constant speed until you get to work. By lugging a motor around it is not very efficent.................and although I don't know what your motor is, stock/mod'd.............driving it with those gears and the 5spd it will be pretty tough to get any kind of good mileage.....IMHO I would think that 3:50's or 3:73's would be a much better choice and allow the motor to operate within the power/torque curves rather than below them. What we did back in the "shade tree" days was to hook up a vacuum gauge and drive with the gauge in the green all the time, this meantit was kind of like putting an egg between your foot and the gas pedal...........but it did not mean lugging the motor around everywhere you went, because if you do.........and drive with the vacuum gauge...it will not stay in the green.............try this, it does work. Just my 3 cents worth.
Thats not neccisarily the case, it all depends on the gears he has in his T5. If he has a standard late 80's early 90's World class T5 then he will have the 3.35:1 first gear ratio, the transmissions were designed to run with 3.07:1 gears. In truth it is the equivalent of an AOD running 3.50 gears if both transmissions pushed 26" tires T5 transmission _________AOD transmission Tire diameter (in.): 26" RPM: 2000 1st Gear Ratio: 3.35 _____1st Gear Ratio: 2.40 2nd Gear Ratio: 1.99 _____2nd Gear Ratio: 1.47 3rd Gear Ratio: 1.32 ______3rd Gear Ratio: 1.0 4th Gear Ratio: 1.00 ______4th Gear Ratio: .667 5th Gear Ratio: .68 Final Drive Ratio: 2.73 _____Final Drive Ratio: 3.5 1st Gear (mph): 17 _______1st Gear (mph): 18 2nd Gear (mph): 28 _______2nd Gear (mph): 30 3rd Gear (mph): 43 _______3rd Gear (mph): 44 4th Gear (mph): 57 _______4th Gear (mph): 66 5th Gear (mph): 83 http://www.apexgarage.com/tech/gear_ratios.shtml And we all know the AOD has similar gears to the C4 with an added overdrive, so he should be getting the performance of a C4 with 3.50 gears So yeah I think his gear ratios should be just fine with that transmission..
I'm certainly not trying to start any disagreements here, just expressing my own personal opinion. The only thing I have to go by is my 97 Mustang Cobra............not quite the same but a fuel injected car with 5spd. It came stock with 3:23's and I got 17/18mpg around town and maybe 23 or so at highway speeds. So I changed to 3:73's and my around town mileage jumped to 18/20 as long as I stayed off the gas............but the highway jumped to 25+ at the same speeds as before.......although the rpm was a little higher. The car had around 288hp to the rear wheels with only adders being headers and Bassani exhaust............along with some external mod's. Formulas and numbers are a great starting place, and sometimes come close to what is actually achieved in the real world............kind of like making 750hp on a dyno and then going out on the strip to find you can only do 9.8's in the quarter when the formula's say you should be in the 9.4's, and yes, I know there are other factors at play here as to why you may or maynot be able to achieve the 9.4, but I am talking in general terms. Theory and reality are/can be two different things.
So what you are saying is you are basing all of the horsepower and fuel economy of this car to your 97 mustang? In other words your comparing a sohc 2 valve multiport fuel injected 4.6L that tend to have no low end torqe but love rpms(this is why ford went with lower gears from the factory) to an old pushrod V8 and expecting the exact same result across the board? Heck there are even differences from how a 5.0HO runs to how a 302 runs. Just look at the horsepower and fuel economy differences between the 1972 302 I took out and the 89 5.0HO I put back in my car and they are based on the same technology. So my question is are we comparing apples to oranges or oranges to kumquats because those motors run completely different and maintain a completely different powerband.:confused: And not just the rear gears make land speed records at bonneville you gotta have high gears in your transmission too
Yes, and no. I have had my share of 289's and 302's, and even had a 1986 Mercury Capri with 5.0l/5spd (came with 2:73's which I promptly changed out for 3:27's then to 3:73's), first year of the injected V8 in Mustang or Capri, but mostly 4spds and automatics in early Mustangs. So maybe I was being to general here, let's take a look at the HP/TQ figures from both an injected 302 and injected 281 motor.............yes there certainly are fundimental differences in both motors and although I am doing most of this from memory I can probably find the information to qualify it as fact. 1986 to ?? injected 302.....200hp/270ft.lb....hp at 3700rpm and torque @3000rpm 1991 injected 302...........200hp/275ft.lb....hp at 4000rpm and torque @3000rpm 1996 injected 281 SOHC....210hp/290ft.lb....hp at 4250rpm and torque at 3000rpm Although my Cobra makes a little more HP and slightly more torque I was just putting kind of an Apples and Oranges comparison out there. Another thing is that the 4.6l SOHC and DOHC love RPM's after you do a little work to them, but stock just disconnecting the revlimiter doesn't do anything for HP or TQ even if you fatten up the injectors just a tad. Had more than a few hours of dyno time on the "Ole Girl", and did 142mph + in 4th gear at the Silver States Classic some years ago with no internal mod's to the motor and my trusty 3:73's and Tremec 5spd. Oh, as for Bonneville...........the gears in the tranmission are dependant on HP/TQ of the motor as most people run quick change rearends. The gears in the transmission can be high or low..............it depends on the motor and rearend. A friend just did 156mph in a 37 Chevy with close ratio 4 spd and 300hp 327................rear end gears were 2.50's. So, all I was trying to do was just throw out some of 40+ years of doing things on paper, then the dyno, both engine and chassis, and real world rubber on the street stuff..................every car is different and every motor is different. I appreciate your comments/thoughts and hope you do mine also........................kind of like the 12 Step Program for AA, if you listen to what they have to say you can use something you heard and if not you can leave it all on the table and walk away.........been there and done that.
Wow sounds like you have been out to the salt flats allot, I have personally only been out to the races 9 or 10 times out there. Did you guys get to check out the barstool races? They only hit 55 or 60mph but on a bar stool thats screaming fast. Is your buddy coming up to run his car at speed week? That starts on monday... Have a buddy who part time does machine work at collins motorsports in vegas, (his brother runs the shop there) but he is heading down for speed week, last year we were down there and they did ok Of course gotta watch out for the carbs, the ones tuned at sea leavel always end up burn the eyes rich up in this altitude, gotta be careful it will get you every time. But for me I was hoping to get out there and hit the 130 mph club this year(its the fastest class I can run without a roll cage) but I cant afford the rims and tires to do it after spending all my money on my transmission so next year I will be out on the salt
Yes, Bonneville is a lot fun, but a lot of work also. My friend's car just did a shake-down without the race motor for SpeedWeek, and the motor is still not ready for next week or El Mirage in October..............most likely next year. The motor is a very radical "flathead Cadillac" with 671 and mechanical fuel injection which should put out about twice what the Chevy did. Here is a picture. I wasn't there for the shake-down but will be next year. You should take the car out for the 130mph club, although I don't know what kind of wheels and tires you currently have, but you just need an H rated tire..........of course you need steel wheels with steel valve stems, because you can't use rubber..................Go for it!
I've had about the same experience, my car is carbed 5.0, when I ran a 5sp I got my best mileage with the motor turning 2300-2400, 25mpg, but I also tinker allot with my proform 650 dp, a buddy gave me one of those cheap air/fuel 02 meters and I kept tuning it till it ran on the edge of lean, my 5sp had the .68 od, 4.11 gears, and the car runs 12.0s on tires.
Nah you dont need steel wheels you car run aluminum. My problem is I just have all season street tires, nothing special, thats only thing stopping me... try finding a set of H rated tires to fit 14" rims without having to special order them by monday
