Hello all, So after an uneventful summer day of doing nothing, I drove to a Kawasaki dealer to look at a bike. On the way home my tranny started puking and luckily I made it home. However, I had a couple questions about the swap. Is there a length difference between C4 and AOD, meaning will I need a new driveshaft? Is there anything I need in particular to do the swap? I'm going to use the V8 that the car came with so where does that take me in terms of parts needed? It's a column shift car, and will stay that way. 4 door Maverick and it will have shorty BBK headers (due to GT40P heads)
Nick, You can use the original drive shaft. You will need a custom rear mount (cross member). You will need to use a TV cable. Might have to clearance the top of the tunnel. Not really worth doing unless you change the stock rear gears. Micah
Im looking into the swap as well. Think Im going with 3.55 gears. 71Gold? has crossmembers available for the swap.
Yes, you would get better milage but your final drive number would be so high that it would not be very driveable. 2.79 x .69 = 1.92 or 3.00 x .69 = 2.07. I'm running a 3.55 (2.44 final). I have Franks crossmember. It worked well. I had to do some massaging, so I recommend a test fit before trany install. Don't get an AOD rubber mount. You will use the C4. Lokar makes a TV cable. Micah
This is the ratio of the rear end (final drive) when you take into account any effect of the transmission. If your transmission has a top gear ratio of 1 to 1 then you multiply your rear ratio by that number, 1 x 2.79 = 2.79. If your transmission's high gear is an over drive with a ratio of 1 to .69, then you multiply your rear gear ratio by that number, .69 x 2.79 = 1.92. There is also the variable of tire size. Micah
They will be about the same until the AOD goes into OD which I believe is about 45 MPH., depending upon your final drive ratios and some internal transmission settings. If your final drive ratio is too high (1.92) you car would be a real dog in OD unless you were driving along very long straight aways with no hills. Great for mileage though. To know the exact excelleration differences, you would need to know the 1-3 gear ratios of your C4 as compared to the 1-3 of the AOD. The goal of an OD is to have a lower final drive (3.55+) for the performance in the city (1-3) but have a lower final drive (2.44) for on the highway (OD). Micah
The fuel inj cars used 2.73 and the .68 O/D but most gear I've seen factory with a carb used a 3.08... Something around 2.40-2.60 final will likely be best for cruising in O/D... That means you'd want rear gears between 3.50 & 3.80... Along with a 2400-3000 lockup stall, it will pull it's ass off in the lower gears while cruising effortlessly in 4th(O/D)...
Also...When running a carburetor with an AOD...You want your rpm at cruise speed in OD to be at least 2000 rpm...Otherwise, most carbs will still be in the idle circuit at cruise speed, this is not good for fuel mileage as the carb will be rich, supplying more fuel than you need at light load cruise speed. (Not good for much else either) Most carbs stay on the idle circuit till 1800 rpm...They start to transition to the main circuit between 18 and 1900 rpm and are on the main circuit at 2000 rpm. Tire diameter also will play a part in this so keep it in mind...The taller the tire. numerically lower the final drive ratio...Just a few things more for you to consider. Its not a huge deal breaker for most but it does make a difference when all is said and done...I have an AOD in my Sprint with 3.80s and 14 inch 235 60 14's in the rear. It turns 2400 RPM at 70 MPH...Good place to be. Also...The carb manufacturer can tell you where the carb you want to use transitions from the idle to main fuel circuits...Just gotta ask, good luck!!! Hope this helps you out.
An AOD transmission does not use a vaccum line or a kick down linkage to get throttle position input to the transmission. It uses a TV cable. It is very important to have and you can damage your transmission if you even briefly run it without one. http://www.lokar.com/downloads/pdf-instructions/ford_aod_kd_kit.pdf Micah
