AOD Question

Topic: AOD Question (Read 5832 times) previous topic - next topic

AOD Question

October 31, 2012, 01:27:29 AM

So I've been talking to BJL about my engine/tranny/rear swap
(93 SC 3.8/AOD/Mk VII 8.8 Posi)
and i have been told that the AOD can seem sluggish compared to the drivetrain w/ a 5spd. Any modifications i can have made to my spare AOD trans that would get some Get-up-and-go down to the road?

What about rear gears?
I have yet to receive my rear but once i do i will know the ratio

AOD Question

Reply #1 – October 31, 2012, 10:38:32 AM

Wide ratio mod. Gets that first ratio up to 2.84:1 second to 1.55. You'll lose .03:1 in the overdrive, but you shouldn't notice. I did mine by transplanting the entire stack from a 4R70W, but not any of the hydraulics, as they are 100% incompatible. Ideally, you want a 4R70W from a 5.4L equipped truck or van, they have more clutches in the forward clutch and the intermediate clutch. You'll need a sharp eye, though, because a lot of the 5.4 stuff runs a 4R100, which is nothing like the 4R70W. All 4R70W's will give you lighter, stronger shells and more clutches in the direct clutch, as well as a 2 inch OD band and drum. It was, I shiznit you not, a direct swap to pull the 4R70W stack and assemble it in my AOD (to which I now refer to as an AODW). I run a 3.73 with mine, I like it, but if I had it to do again, I'd do a 3.55 because of how much time I spend on the freeway. This will relieve the tendency of the AOD to WOT upshift at under 5000 RPM.

AOD Question

Reply #2 – October 31, 2012, 04:56:03 PM

Ok cool so what if i get upgrade parts from:http://www.broaderperformance.com/34-ford-aod
Are there any other upgrade transmission parts i might want to invest in while building?

Thanks for the info

AOD Question

Reply #3 – October 31, 2012, 06:48:09 PM

None that I can think of. Best bet is to get a used 4R70W, gut it, and replace all the clutches and steels. Make sure to use the 4R70W type, as they have grooves in the clutches that allow fluid to escape from in between quickly, this will help make sure you have good positive shifts, and will help reduce slipping during engagement. What you give up in surface area, you'll gain in holding capacity. And above all else, be sure to set the Throttle valve precisely, or you'll burn the thing up in 50 miles or less.

I didn't ask, but what is the power level you're dealing with? I see that we're talking about a 3.8, but I know a performance aftermarket is starting to rise up for these, so I thought I'd ask.

AOD Question

Reply #4 – October 31, 2012, 08:37:04 PM

Quote from: TheFoeYouKnow;401689

...This will relieve the tendency of the AOD to WOT upshift at under 5000 RPM.

That's not a "tendency", the AOD in the fox t-bird/cougar and mustangs came with a 4700rpm governor, it's designed to shift there....combine the wide ratio swap with a Silverfox valvebody and you have a serious transmission on the cheap with the ability to adjust WOT shift rpm within a given window.

Good luck,
Don

AOD Question

Reply #5 – October 31, 2012, 09:00:37 PM

I've heard other guys talk about a 4700 rpm governor, too, but I didn't mess with my governor or my valve body, and after wide-ratio and 3.73, I can wot upshift at 6200. In fact, the original Ford Racing wide ratio Kit instructions warn of this, because some guys installed aftermarket governors and the combo of that plus the kit would cause the trans to either slip on upshifts or not upshift at all.

AOD Question

Reply #6 – November 01, 2012, 02:00:23 AM

Currently the only mods my engine has is a chipped ECM and a 10% pulley on the SC but that is what i was told, i haven't started seeing what else is there. Supposedly the output is 220hp and 310tq so im guessing around there for now.

AOD Question

Reply #7 – November 01, 2012, 07:11:15 AM

You shouldn't need to go crazy then. A good AODW build with V8 parts like I described should be much more than adequate. Mine, according to my research, should be good for 450 HP if I add a performance valvebody. I haven't yet because I'm only in the 265-275 range currently.

AOD Question

Reply #8 – November 01, 2012, 07:28:30 PM

The real question is WHICH aod do you have...if it's a supercoupe aod, you already have a pretty tough trans that's already packed with "V8" parts and really may just need a looser convertor...those SC 3.8's make most of their torque down low and early and a stock AOD 1st gear is fine...you really won't gain much in that combo with the 4R70W guts, but you will gain a little more durability, as those we're still stronger than AOD's....you certainly don't want to spin that 3.8 to 6200rpm either...at that point, you'd just be making noise....

If you have the stock 3.8 AOD, baby it until you can afford something better....what would really be helpful is if you put some sticky tires on it and went to Atco to make some runs so we can see what it's doing.

Good luck,
Don

AOD Question

Reply #9 – November 01, 2012, 09:11:53 PM

Thanks for the question,

I have both, My drivetrain i bought has a rebuilt 93 SC AOD (out in my garage) but my bird has its stock 3.8 AOD in it now

AOD Question

Reply #10 – November 01, 2012, 11:42:50 PM

Quote from: TheFoeYouKnow;401689

Wide ratio mod. Gets that first ratio up to 2.84:1 second to 1.55. You'll lose .03:1 in the overdrive, but you shouldn't notice. I did mine by transplanting the entire stack from a 4R70W, but not any of the hydraulics, as they are 100% incompatible. Ideally, you want a 4R70W from a 5.4L equipped truck or van, they have more clutches in the forward clutch and the intermediate clutch. You'll need a sharp eye, though, because a lot of the 5.4 stuff runs a 4R100, which is nothing like the 4R70W. All 4R70W's will give you lighter, stronger shells and more clutches in the direct clutch, as well as a 2 inch OD band and drum. It was, I shiznit you not, a direct swap to pull the 4R70W stack and assemble it in my AOD (to which I now refer to as an AODW). I run a 3.73 with mine, I like it, but if I had it to do again, I'd do a 3.55 because of how much time I spend on the freeway. This will relieve the tendency of the AOD to WOT upshift at under 5000 RPM.

Do you have traction issues with the wide ratio upgrade? My trans guy said if I had gone with the wide ratio upgrade I would have traction issues and not see much if any of an improvement in ET. I do have a 2800 non lock up converter, and traction issues. I would say that if he's building the trans a good, higher stall torque converter is a worthwhile upgrade.

AOD Question

Reply #11 – November 02, 2012, 08:10:14 PM

Definitely install the SC transmission...I think you'll blow those skinny tires off no matter what first gear ratio you have...lol.

AOD Question

Reply #12 – November 02, 2012, 08:14:23 PM

I don't have traction problems, except the open diff I still have out back.

AOD Question

Reply #13 – November 02, 2012, 08:56:27 PM

Some may consider that to be a major traction problem...lol....my CV was almost undrivable when I first got it with the 3.08 open rear and 215/70R14's...a T-Lok and some 3.73's coupled with the 235/55R17's solved those problems...until I put in the 351/T5...lol. It's all relative...the way I see it...if you can't launch it like you're angry because you might spin...you have traction problems...lol.

-Don

AOD Question

Reply #14 – November 02, 2012, 11:29:10 PM

Yeah the rear tire will be gone, getting rear 15" steelies and i will throw on 255/70R15 wide whitewalls in the rear as long as they fit in my wheel wells