SST A41 perfect fit kit

[Soy bomb]

Anyone have experience with SST's A41 perfect fit automatic  OD tranny?  I was thinking of the stage 2. I was also curios how to determine what rear gears to install in combination with this unit. What would be the advantage or disadvantage of 3:73 or 3:91 gears and overdrive ? I'm not sure how to calculate the cruising rpms in OD with these gears?

[ragtopdodge]

https://www.ringpinion.com/calculators/Calc_RPM.aspx

[jordan]

I have one.  I got it from Keisler.  That was a total pain, but once I got all my parts, I have to say that I love it.  It came set up with perfect shift points.  It is responsive and smooth.  It can be hand shifted, or just put your foot into it and it will choose the correct gear.  I have no complaints.  There is minimal body modifications to get it to fit.  You do need a laptop to get it set up, but it wasn't hard.  I think getting the TPS set up is most critical and a bit time consuming, but all in all, not very difficult.  I run a 3:23 rear with a 25" low profile tire.  2200 rpm at 65mph.  I haven't heard anything bad about SST.  They have to be infinitely better than Keisler.  The oil pan hangs low, but I have never hit anything with it.  The only drawback of this transmission is saying that you have a GM part in your Mopar. 

[Soy bomb]

Jordan, thanks for your input! Curious why are you running such high gears with the overdrive ? Seems you should still be in the mid to upper 2000's rpm wise cruising with 3:73s, no? It would give you a much better launch,... when you wanted. Did Keisler have input on that .?

[1 Wild R/T]

Thats the whole point of an overdrive... In lower gears it has enough gear to launch very well but when you get it in high gear (overdrive) it can cruise the freeway effortlessly.....

[Soy bomb]

I know. But if you have 2:76 gears or something similar, you don't need OD. A 3 speed is fine .

[brads70]

I also have the Keisler kit.Stage 3  No regrets! I also have a Strange S60 Dana with 3:54 gears and am currently changing to 4:10. I found it to almost lug at 2000 RPM hence the reason for the gear change. It also depends on the engine/tire combo....  I never needed to use a laptop to set up the A41 kit. (Simple shift controller.) I like the 3.06 first gear ratio over the 2.54 of the 518, also lighter especially spinning weight. 

[jordan]

I went with the taller gears because I have a pro touring car.  My tires are only 25" tall, not 27"-30"like old school cars. I have a car that has a 140mph top speed.  I have a car that pulls hard in the 50 to 100mph range.  I have enough power to light off my tires at will now.  I can't imagine if I was geared any tighter.  I would rather road race than drag race.  I haven't found my gears to be limiting for my usage.  The plus side is that it can cruise down the interstate at 70mph very easily. 

[moparman82]

Jordan would u mind posting a pic of ur car?  That little avatar photo is just enough to get me drooling but I'd love to see a full size pic if u have the time

[Soy bomb]

Brads70,

Can you explain more about the " lugging " at 2000 rpm ?

[Soy bomb]

jordan,

Thanks for the explanation. That's the kind of real use description I'm looking for. Appreciate it !

[brads70]

Brads70,

Can you explain more about the " lugging " at 2000 rpm ?

My engine is not in the power band at 2000 rpm. It would depend on your engine/cam/ stall speed combo but mine runs much nicer at 80-85 MPH which the police frown on so when I up the rpm with a gear change it will solve that issue.  I suspect it will also help with fuel economy around town.... as long as I stay off the pedal.

[Soy bomb]

 

[jordan]

Hey Moparman,  Here are a few photos.  Probably not that great of ones.  I was using my phone camera and it was starting to get dark.  But here are a few anyways.  Thanks for wanting a look.  I thew in one of the transmission since this is the drivetrain thread. 

[Soy bomb]

I'm typically not a resto mod type of guy,... but I'd easily admit that is one SWEET looking ride !!!!!