Auto Trans for 351W
 

Does anyone have any experience with an automatic transmission for a 351W? I'm street only and dont want to do any type of racing. Therefore, I'm looking for something more in the cruiser style. Of course, I'd like to be quick off the light....

I currently have a truck c6 3speed that's too low for highway. First is useless, so its only used in second and third.

Would greatly appreciate inputs and names of vendors. Thanks in advance.

Kind of like making love to your wife with a condom.

Roscoe

If it wasnt for hydroplaning I probably still would.

Actually, 2nd is pretty good for take offs up to about 35 and 3rd takes me up to about 80. However at 80 I'm doing 4k rpm - kinda too high.

I just wished there was one more gear as the ratios for 2 & 3 are ok.

Yo leejleej,

Almost sounds like too much gear. What's the rear axle ratio? Changing that to a lower number might solve the 1st gear and top end problems together!

For example if you have a 4.11 you might consider jumping up to around 3.50 or even a 3.30

Tom

the rear end is from a BMW E36 with a 3.15.

I asked the vendor (Venom Perforcars) the exact spec so I can ask the BMW dealer without sounding like the total neophyte that I am. But havent gotten a response.

If I can replace the pinion gears to a 2.75 or even 2.5 , yes I agree that may do the trick and probably the cheaper way to go.

thanks,

leejleej,

What size rear tires are you running? I run 315/35/17 with a 3.50:1 gear and am not spinning that high at that speed. This past weekend I took him out for a highway joust and hit 105 mph, I think my rpm at that speed was only around 5000. I also run a C6 and use all 3 speeds and my first gear is not useless. A matter of fact, when I stomp it from a stand-still I get very little tire spin, it just goes. Of course Cobie has just shy of 25" of rubber on the ground in the rear too. I actually need more power and if he doesn't sell by Winter, he'll get it.

John

351W with an Auto
 

Hi lee,

I was running a C-4 behind my 351W with 3.50 rear gears and to do 60 I was spinning 3k on the tach. I blew either the front seal or the front pump about 2-1/2 weeks ago and it somewhat of a blessing in disguise. I had been contemplating swapping out the C-4 for an AOD and the C-4 problem was the proverbial straw that broke the camel's back.

Anyway, I'm just about done with the swap and hopefully tomorrow I'll fill it with fluid, adjust the Throttle Valve cable and get it back on the road.

Some of the other guys in here run AOD's and they all have nothing but positive things to say about them.

BTW, I got my AOD & converter from Summit. The tranny is a TCI and the verter is a B&M. Some guys are running Lentechs, but they were a little too pricey for my budget.

I'll let you know how the AOD works out for me.

Tony

If you have good mechanical aptitude, you could do the same thing I did on my brother's 85 Crown Vic I rebuilt the AOD that was in it and while I had it apart I put in some goodies from Hughes Performance. You stated you have a C6, not a problem; go to a salvage yard or other source for a usable base, no cracks parts missing or not completely melted and order a rebuild kit, most send at least a set of instructions, for the love of god read the dang instructions also don't scrimp you want to save money not cut corners, go with a premium type kit with almost everything included, Hughes has a premium race type kit for less than $500 and after you include the trans purchase price you still are running Less than $1000, about $500 cheaper than the Aftermarket rebuilts. Of course that is if you pay attention when you disassemble the trans and follow the instructions.

sounds like a great idea. Unfortunately my mechcanical aptitude starts and stops with oil changes. I will look into the Hughes and see if my friend will help me.... At this point my wife is really making me eat my words about how low-cost this would be....

I'd look ino either a built C4, or AOD. There are lots of good trans shops in NJ. Try Joey R's in East Orange.

Lentec ( a Canadian company) offers an AOD that is supposed to be good to 750+hp. I think their website is Lentec.com

AOD
 

I'VE GOT A 351W WITH A AOD IN IT. GREAT TRANNIE! NINE INCH WITH 3.5 GEARS. ABOUT 2000 RPM AT 70 MPH. SHIFT UP AND DOWN WITH NO PROBLEM. A 4 SPEED AUTO IS THE WAY TO GO IF YOU WANT AN AUTO TRANNIE IN YOUR COBRA.

leejleej

I have a Backdraft with a 351 and an AOD. I think the Venom and BDR are nearly the same. I really like the AOD, I would get a converter with a little higher stall. I purchased the AOD from a performance builder and could not be happer.

Sitting at a stop the car will break the tires loose very easy and at 100 mph in OD it is only turning about 2500 rpm - not that i have ever had the car about the legal speed limit.

I highly recommend Hughes Performance --

jim

Thanks to all for your inputs.

Hughes looked pretty good... Diffsonline.com is also an option for about $1500- not counting installation.

Boy, more fun!

A great weekend to all.

Lentech Automatics makes several great AODs. They are very well respected in the Mustang community and have really good customer service. A little pricey, but you get what you pay for.

I have their Street Terminator Plus .


Pete

I'd never been convinced about an automatic box in a performance car until I put a BMW 4.4 V8 with 5 speed tiptronic box into a Cobra.

Keep the box in normal mode and it is smooth as silk and you never feel or hear the gear changes, perfect for the horrible traffic jams we get over here.

Then put the box into sport mode, floor the throttle and its pure Kamikaze mayhem, hardly any wheelspin and the car just keeps accelerating like mad with only the rev limiter just about cutting in at changes from 2nd to third.

As yet I've only had the car to 135mph max and it was still pulling like train. As usual I chickened out and slipped the gearstick across the gate and lifted off the throttle. The gearbox, realising that more acceleration wasnt needed, slipped up a gear into 5th...........

Absolute madness but talk about fun and the grin factor..............

Cheers,

Tony

I also asked on Trannies section. But are there any quirks to the AOD 4 Speed?

thanks to all.

jong

Didn't know we had a tranny forum :o

If you go with AOD, you really ought to at least get a valve body with overdrive lockout. The shift pattern on an AOD shifter goes 1-D-OD. This means that there is no way to manually select 2nd gear.

To fix this, you can get a valve body loke the one from Lentech (Street Terminator AOD Valve Body) that has an electric overdrive lockout. These valve bodies come with a swith that you mount in the cockpit to turn overdrive on or off. With overdrive turned off the shift pattern is 1-2-D. With overdrive on the shift pattern is 1-2-OD.


Pete

Lee,
I am building a Cobra with a 351W and 4R70W trans which is essentially an electronically controlled AOD. Search on Baumann Engineering and you will find that they make an electronic control module which is similar to the tiptronic referenced below. We are hooking up 'paddle shifters' to the steering wheel to get manual shifting on an automatic. The Baumann box gives you full control of shift points by RPM range and throttle position. It is an unbelievable unit and a reasonable price. The 4R70W has lower gearing than the AOD and all the latest Ford goodies. I picked up a brand new crate tranny for $500.

AOD's
 

The only issue with Ford AOD's is that the shifting is conrolled with a throttle valve instead of with vacuum like the C-4 & C-6 trannies.

If you're running carburetion you'll have to get a throttle valve cable assembly, I used Lokar, to connect the TV linkage to the carb. Once that is done, the adjustment has to be done just right or you can burn out your clutches within a few miles.

The AOD has a TV pressure port on the passenger side and it is recommended that at idle, in neutral (not park), the pressure should be between 0 and 5 psi. Then you have to use a gauge that is a block with a slot that fits over the TV cable at the carb end. The block is between .390 & .400" and you insert it between the end of the cable and the plastic cable stop. With the tool inserted you should have apprximately 32-35 psi with no less than 30 psi.

I used a TCI Streetfighter tranny and the TCI tech walked me through the adjustment and all worked well for about a day. Then I lost reverse and then I lost all my forward gears. We are not sure what happened or caused the problem, but TCI is warranteeing the tranny. I just shipped it back to them and I should get the new one within a week or two. They said they will either repair or replace the unit. My suspicion is that they will just swap it for one off of their shelves.

Regarding the TV pressure, from what I have read, more TV pressure is better than less pressure.