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Topic: Increasing efficiency, within reason? (long post) (Read 3957 times) previous topic - next topic

Re: Increasing efficiency, within reason? (long post)

Reply #45 –
get the 200 CI inline six and then when that brakes down you can test fit the super charged 300
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

Re: Increasing efficiency, within reason? (long post)

Reply #46 –
or you could find a 83-86 xr7/TC for cheap and just turn the boost down to 5 or 6 pounds
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

Re: Increasing efficiency, within reason? (long post)

Reply #47 –
Quote from: slamedcat
That equation cam from a "Mast Fittment Guide" that was at the shop I worked at. The book is put out by Michilen of North America.

Not to be pissy but try telling them their wrong.  :rolleyes:

I also understand what you are saying. But what about cyntrifical force pulling on that tire when its do 80mph. Its not going to have the same dia when its moving.


Yeah, but also keep in mind centrifugal force won't cause it to grow that much...if it were a drag slick, sure...but 6 or 8 ply tires won't grow an inch in diameter, maybe a quarter inch at the absolute most.  The equation, in theory, is good but it doesn't calculate for a loaded tire or differences in tread depth or inflation pressures.  Give me their contact info, I'll tell'em their wrong...lol.  :hick:
Project 3G: Grandpa Grocery Getter-'85 Crown Vic LTD 2-door, 351W with heavily ported/polished GT40 heads, heavily ported/polished Typhoon Power Plus upper & lower intake, Comp Cams 265DEH retarded 1*, FAST EZ-EFI, HD T5, 8.8" 3.73 trac lock with extra clutches, 3G alt. swap, '99 CVPI front brakes, '09 CVPI rear disc brakes, '00 CVPI booster&m/c + wilwood adj prop valve.

Parted & Gone-'88 T-bird Sport, 351W swap, ported GT40 heads

Re: Increasing efficiency, within reason? (long post)

Reply #48 –
the 200's only get in the 20's around town normally 18-22 mpg

Re: Increasing efficiency, within reason? (long post)

Reply #49 –
I get far better fuel mileage with 3.73s than I did with 2.73s (especially in town- probably only 1 mpg on the hwy).  The car moves like it weighs 800lbs. less and on the hwy I'm only doing 23-2400 at 70mph.  Best mod yet.  Better Acceleration and mileage. 
 :canada:

Re: Increasing efficiency, within reason? (long post)

Reply #50 –
OK, I had to resurrect this because I actually sat down and ran some numbers I've been toying with for awhile now.

One of the things I've thought about doing was tracking down a used  4R70W (wide-ratio AOD-E, more or less) in the 3.8/4.2/300/5.0/5.8/etc. bellhousing bolt pattern (I'm led to believe they exist..  and putting that in place of the LSC's AOD along with a Baumannator TCS to control it. Eh, maybe.. until I saw you guys talking about rear end gears and getting mileage improvements (city mileage, anyway) with switching to a numerically higher rear gear.

I whipped up a new piece of my infamous (to the people I regularly annoy with it, anyway) gear ratio calculator spreadsheet. Listed my current rear gear, (3.27) and the gear ratios of the 4R70W and the AOD, and it calculated out the final drive ratios for each gear in each transmission. I also did some lines below that for comparison: using the 1st, 2nd, and OD gears from the AOD along with differing rear gear ratios for comparison to the numbers the 4R70W generates.

How does this look to those of you who mess around with (or think about messing around with) alternate gearing? Unless I'm doing this all wrong, it looks like the 4R70W with my current rear gear would be roughly the equivalent (I'm approximating in this example) having an AOD with close to a 3.89 rear gear for 1st gear, close to a 3.73 rear gear for 2nd gear, my current 3.27 for 3rd, and again up to between my stock gear and a 3.55 for OD.

(and I pulled the 3.89 ratio from Summit.. they have one for sale.. didn't know that there was something between a 3.73 and a 4.10)

In addition to that, this setup would allow me to tweak all shift points, keep a second set of shift points that can be switched to, tweak line pressures and torque converter clutch settings, (not stuff I'd be ready to mess with) and other such nifty things like being able to use the cruise control buttons for manual shifting in an alternate function mode. That is, if Baumann delivers everything they say they deliver.

Yes, it would cost a pretty penny.. but again, this is an expense I would consider as spread out over the lifetime of the car.. and as I see it, it would also save me from tinkering with rear gears and shift kits and other stuff like that. The 4R70W is also supposed to have some stronger components than the AOD, like the input shaft and the OD servo.

Re: Increasing efficiency, within reason? (long post)

Reply #51 –
You're basically ' in the wind if you think playing with tranny ratios is going to give any noticable gas milage improvement. Yea you might get 2-3 TENTHS... ought to be able to recoup that in 25 years or so...

The ONLY modification that may help, is to run a milder cam that lets the engine make peak torque at a lower rpm. Then with fewer revolutions per mile, there is less internal friction. For instance there may be enough friction to rob 25 hp at 2000 rpm but only 20 hp at 1600.. That's five hp less the engine has to produce just to run, and that will save fuel. Years ago after the oil embargo and rising prices, several cam vendors offered "econmy" cams that were just mild cams that proudced good low end torque.

As I stated some posts back, the greatest improvement will be to install a vacspooge gage and drive by it. Never let the vac fall below 5-6" and you'll get a noticable improvement. The gage will likely pay for itself in 4-5 tanks.

Re: Increasing efficiency, within reason? (long post)

Reply #52 –
I have a vacuum gauge.. can't really read it while I'm driving because I can't mount it in a way that allows me to see it easily while moving.. not without mangling the dash. (at least until I figure out a more creative mounting solution)

What about an Explorer's cam?

EDIT: I still think I might do the 4R70W conversion even if it isn't much better mileage-wise, just for all the other little benefits. (the ones I see, anyway.. heh)
 

Re: Increasing efficiency, within reason? (long post)

Reply #53 –
As a side note, not addressed to anyone, I'll sort of repeat this from the other night:

Please avoid any "just get this" types of comments. This is about ideas on improving the fuel efficiency of a car I already own.. and doesn't necessarily mean a project will happen because of this thread. (although the 4R70W swap is likely at some point, efficient or not) Besides.. I confess, I started looking for 1989-90 Honda Civics/CRXes in the state, for a beater work car. Checking into a $500 CRX HF 5-speed I stumbled across. It would mean I'd have to get the '88 T-bird out of the yard to make room for it, though.