AOD opinions

[mean78]

i have a 88 gt that i got for cheap and i am planning a build around 400hp, its a budget build and im just wanting to do what i can with the stock transmission

its got 140k miles, and i was wondering what i can do to it, i have been told to just do a manual valve body then like a 2700 stall converter.

then i have also heard about drilling the valve body to get rid of the overdrive shuffle.

also what can this thing hold before i need to worry about breakin anything internally? what about the forward drum?

what do you guys recommend for a street car? i still want it to have street manners.

 

[mean78]

wow......

this site is a huge help

 

[795.0pacecar]

When no one knows, would you rather have bad advice, or no advice?


If you are going to do anything performance wise to either the engine or trans, first and foremost you need to rebuild it. I would get a manual reverse valve body and I would base the stall on the engine combo. I'm not sure how much an internally stock aod can handle.

 

[squeak93]

Ok. I have a 351 with an aod behind it. Let me try to help to save u some frustration. It took us 5 trys to get it right, but now that it is, its great.

I have an aod with a 4r70 gear set in it. Aode bands (second gear for sure, not sure what else as I forgot exactly what my transbuilder put in now) But it has good clutches, a superior shift improver, and a basic stock valve body. I have to 1 d 1 shuffle but its not that big of a deal. I run my rpms to 6800 and it holds just fine...... So take it to a reputable pro who has done the mods u want before. I run a 3500 non lock up stall. I can tell u I like the rpm but wish I had gotten a lock up soley for mpg purposes.

 

[88lxmuscle]

I run an AOD i got a stage 2 shift kit and hold high revs, pretty nice for a auto.

 

[Foxbox]

Mines always managed to hold up. Still though, you always get those looks like
"THATS an AUTO?? UGH"

 

[RYC CUKR]

There are several weak points to the AOD.

1. The stock OD servo, a B servo, is to small. Upgrade it to an A+ or A++ OD servo. WOT in OD with the stock servo can quickly to a 3 speed AOD. I know from experience. This can be done with the trans in the car.

2. The stock inner input shaft, the direct drive one, is weak and can break when the car shifts into D while under HEAVY throttle. A non lock up style converter will help soften the blow to the shaft by allowing some slippage in D instead of the direct drive. If you want to run a stock style converter, with a higher stall of course, get the hardened input shaft.

3. The 88 does not have the best lube circuits especially in the tailshaft bushing. I believe that 89s and up have a better lube circuit for the tailshaft bushing. There is a mod that can be done to improve the lube circuit and the write up is over at www.clickclickracing.com. This is more important in cars with lower gear ratios i.e. 4.10s and such.

4. The valve body was changed between 88 and 89 and the accumulator set was improved. The 89 valve body is a bolt in swap. My 93 has an 88 AOD and I swapped the VB off the busted 93 AOD onto the 88 and it works just fine.

5. On the VB you should install the Sonnax valve fix. Pretty easy to do.

The cliclickracing website has lots of AOD tech info and a couple of really great sticky threads of important mods for the AOD. In fact here is a link to the mod thread started by Silverfox http://www.clickclickracing.com/forums/showthread.php?t=2444

Good info in there.

 

[mean78]

ok so i have definatley heard about the input shaft being very week.

and i have heard about the epoxy mod, is this worth it? what exactly would i gain?

also cross drilling the VB? what would i gain form this?

basically i want to get what i can out of this without having to go and change out bands and anything else major, then build one on the side

 

[mean78]

There are several weak points to the AOD.

1. The stock OD servo, a B servo, is to small. Upgrade it to an A+ or A++ OD servo. WOT in OD with the stock servo can quickly to a 3 speed AOD. I know from experience. This can be done with the trans in the car.

2. The stock inner input shaft, the direct drive one, is weak and can break when the car shifts into D while under HEAVY throttle. A non lock up style converter will help soften the blow to the shaft by allowing some slippage in D instead of the direct drive. If you want to run a stock style converter, with a higher stall of course, get the hardened input shaft.

3. The 88 does not have the best lube circuits especially in the tailshaft bushing. I believe that 89s and up have a better lube circuit for the tailshaft bushing. There is a mod that can be done to improve the lube circuit and the write up is over at www.clickclickracing.com. This is more important in cars with lower gear ratios i.e. 4.10s and such.

4. The valve body was changed between 88 and 89 and the accumulator set was improved. The 89 valve body is a bolt in swap. My 93 has an 88 AOD and I swapped the VB off the busted 93 AOD onto the 88 and it works just fine.

5. On the VB you should install the Sonnax valve fix. Pretty easy to do.

The cliclickracing website has lots of AOD tech info and a couple of really great sticky threads of important mods for the AOD. In fact here is a link to the mod thread started by Silverfox http://www.clickclickracing.com/forums/showthread.php?t=2444

Good info in there.

so if i went and found a 89 VB (given you said they were better because they improved the acumulator) what would you recommend doing to it to get it to performe a little better? but still have good street manners?

and also what is involved in upgrading the input shaft?

sorry a little new to autos

 

[SVT32VDOHC]

By the time you get all those parts purchased and installed, it might be cheaper to just buy a completed rebuilt and beefed up AOD from a supplier. There are plenty in the mags that advertise. Some of their builds have a warranty....it just depends on which one you get and how much power you put behind it. Even if you get 30 days....that's fine, because you can get plenty of passes in 30 days.

 

[RYC CUKR]

As far as the VB goes, I would put a shift kit in, Baumann makes a nice one that goes for around $60. And while your at it I would upgrade to the Sonnax boost valve. The line pressure will come up quicker and will result in less slipping of the clutches during shifts. They go for $40.

With the input shaft that is something that will need the trans to be pulled in order to swap. Once the trans is out and the converter removed the input shaft swap is really simple. Just slide the old one out and slide the new on it. Easy. This is something that I would do when the converter is swapped. Pulling the AOD twice is not a lot of fun. The hardened input shaft usually runs about $170.

When swapping the VB I would do the overdrive servo at the same time. Might as well do it while pan is off and stuff. The A+ OD servo is about $130-140 depending on where you get it. It isn't a hard job. Basically you use an old coat hanger to hold the lip of the OD band in place while you remove the old servo. The old servo comes out by removing an inner snap ring and it pulls out. Put the new servo in. You might have to do a little filing on the servo tip to get the proper tolerance, I did, but its no big deal. Once the new servo is in you can remove the coat hanger wire and you have just swapped the OD servo on and AOD.

I have no personal experience with the epoxy mod so you should check with the guys over at clickclickracing and see how they like it. From my reading it takes the crappy stock shift set up of 1,2/D, OD to 1,2,D/OD. So on the shifter the D position becomes 2nd and the OD position becomes D/OD. You can hold second gear unlike the stock set up but D/OD occupy the same position on the shifter. I have read that it will not shift into OD under WOT. But I would talk to guys with experience with it to get the straight skinny.

 

[mean78]

As far as the VB goes, I would put a shift kit in, Baumann makes a nice one that goes for around $60. And while your at it I would upgrade to the Sonnax boost valve. The line pressure will come up quicker and will result in less slipping of the clutches during shifts. They go for $40.

With the input shaft that is something that will need the trans to be pulled in order to swap. Once the trans is out and the converter removed the input shaft swap is really simple. Just slide the old one out and slide the new on it. Easy. This is something that I would do when the converter is swapped. Pulling the AOD twice is not a lot of fun. The hardened input shaft usually runs about $170.

When swapping the VB I would do the overdrive servo at the same time. Might as well do it while pan is off and stuff. The A+ OD servo is about $130-140 depending on where you get it. It isn't a hard job. Basically you use an old coat hanger to hold the lip of the OD band in place while you remove the old servo. The old servo comes out by removing an inner snap ring and it pulls out. Put the new servo in. You might have to do a little filing on the servo tip to get the proper tolerance, I did, but its no big deal. Once the new servo is in you can remove the coat hanger wire and you have just swapped the OD servo on and AOD.

I have no personal experience with the epoxy mod so you should check with the guys over at clickclickracing and see how they like it. From my reading it takes the crappy stock shift set up of 1,2/D, OD to 1,2,D/OD. So on the shifter the D position becomes 2nd and the OD position becomes D/OD. You can hold second gear unlike the stock set up but D/OD occupy the same position on the shifter. I have read that it will not shift into OD under WOT. But I would talk to guys with experience with it to get the straight skinny.

thanks you guys have been big help, im really timid on autos, the only auto i have ever build was a th350, we put in a transgo kit with a hardend shaft. and that trans is still holding up to some mean launches

ill look into finding a hardend input shaft and then lok for a 89 VB that i can work on (sonnex, cross drill, and maybe the epoxy mod if i learn enough about it)

if i had a e303 cam and gt-40y heads and a stock bottom end, what would you guys recommend on converters?

 

[ill advised]

Good info, RYC CUKR. Thanks.

As an aside: mean78, if you're going to run n/a with the e-cam you'll want to have a pretty steep gear.

 

[RYC CUKR]

Personally I would run a TFS stage 1 cam. That is just my preference. Lots of things play into converter selection other than just the cam. Gear ratio, weight, intended use of the car. I would figure out what gear you to run, get the car weighed and call up one of the converter companies, lots of guys are pretty pleased with the Edge converters, and let them make some recommendations They have a lot more experience with selecting converters than I do.

I just swapped a 3000 rpm non lockup into my 93 vert. Haven't been to the track with it yet so I don't have any times but it feels strong. If you are going to drive the car a lot or rely on it for transportation I would not go with a non lock up since it will hurt you milage due the slip built into the converter.

Also get a big stacked play trans cooler. This is a must. The AOD does not like heat.

 

[squeak93]

10 MPG HERE BABY....3500 NON LOCK UP!!