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looking for bolt on 5sp to my 1970 Hemi

WoolyPig

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So i am wanting to put a bolt on 5sp manual tranny in my superbird but Passion Performance is 10 to 12 months out to get one.

anyone have other suggestions on where to pick one up? I'd like to keep the OEM gear ratios
 
Yeah I don't think that is going to happen. The Passon 5 speed is the closest thing to a bolt in but you'll be pushing your luck with Hemi power. The next option would be a TKO based kit but I'd think one of those would be very iffy behind a Hemi. You could step up to a T56 kit but those are nowhere close to a bolt in.

I think your only option is to get in line for a Passon and then once you have it installed be gentle with it.
 
you think the OEM 4sp tranny is just a better way to go? I was going to rebuild it which would cost $2500 and thought getting a passion for $5k would be smarter.
 
A 4 speed rebuild shouldn't be more than $400 unless something is trashed.
 
it is a complete rebuild, all internals.
 
Wooly, is your trans acting up etc. I'm assuming it is an 18 spline.
 
you think the OEM 4sp tranny is just a better way to go? I was going to rebuild it which would cost $2500 and thought getting a passion for $5k would be smarter.

Just depends on a bunch of factors which you haven't told us yet. Is this a resto type car? Numbers matching? Show poodle? Daily driver? These days an original Hemi Superbird is most likely a show poodle that sits in a climate controlled garage except for a couple of times a year when it is pushed onto a trailer to go to a car show. In that case who cares what transmission is in it.

If you're actually driving a Hemi Superbird on a regular basis and you want a fifth gear for some reason then Passon is probably your only decent choice. Brewers does charge $2500 for a new Hemi four speed transmission but if you have a numbers matching box you don't want to trade your existing box in for a core. A local trans guy should be able to rebuild your box for a few hundred bucks unless it has been totally destroyed.

Most people wouldn't need a 5 speed in a Superbird since they aren't going to drive a Superbird hard enough to need another gear. If you drive yours so hard that you need more than 4 gears then you are a very odd duck. Even if you're that odd, I doubt that your odd enough to cut up an original Superbird to stick a TKO or T56 in it. Which leads me back to the Passon option.
 
Have you thought of gear vendors? Handle 2000 hp
 
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it is a restomod so no it's not numbers matching. I plan to drive it and not worry about miles. obviously i won't drive it like a daily driver but im not gonna trailer queen it.
I figured if i was going to sell the car a 5sp would be more desirable and pay for itself.
but if the passion won't hold up to a hemi, which i do plan on getting on the car hard at times, then it's probably not the way to go.
 
Are you using a Dana and what gears?
 
Passon also offers a four speed overdrive gearset
4th is .80
 
Yeah I don't think that is going to happen. The Passon 5 speed is the closest thing to a bolt in but you'll be pushing your luck with Hemi power. The next option would be a TKO based kit but I'd think one of those would be very iffy behind a Hemi. You could step up to a T56 kit but those are nowhere close to a bolt in.

I think your only option is to get in line for a Passon and then once you have it installed be gentle with it.

I just got my Passon 5 speed. It will handle 700 Foot Ponds of torque, so it should be fine behind your Hemi unless it is a total monster engine. 1-4 gears are similar ratios to the 4 speed A-833, and 5th is .70. However, don't believe the 12 month wait - I waited a lot longer than that. Production has been slow.

Hawk
 
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I don't think you would want 3.55 rear gears with a Passon 5 speed. The OD would turn the rear end into a 2.50 which is going to be too steep for most performance engines. If you have a performance cam in the Hemi then you'll be lugging the motor in 5th. You need to figure out what speed you want to cruise at in 5th gear and then figure out what the torque curve of your engine looks like and then pick a rear gear that puts you in the fat part of the torque curve. My guess is that you might want at least 4.10 rear gears with a Passon 5 speed. Maybe even a 4.30 gear. With that setup you can romp thru the first four gears like a drag car but when you shift it into 5th you'll be going down the freeway as if you had 3.0 gears.

I run 3.23 gears in the Dana 60 in my Coronet but I have a Doug Nash 5 speed in it. The Doug Nash has a steep first gear but 5th is 1:1 ratio. So you have to put a high rear gear in it rather than a low gear. The 3.23 gears are just about perfect in that car.
 
Let us know if you get a Passon in 12 months. At least call SST Silver Sport to check the details.
 
My A855 has been nothing but trouble. Pops out of 4th since day one, mile .5.
Plus, the so called shipping crate is a joke.
 
i think im just gonna rebuild the 4spd like new and throw it in. with 3.55 gears it should be right. If or once i get the passion i'll change out the gears.

isn't the OEM 4sp actually a 3sp with an OD?
 
No, in the early 70's the a-833 was converted to the OD. when the gas shortage/mileage issue came about.
 
No, in the early 70's the a-833 was converted to the OD. when the gas shortage/mileage issue came about.
So in the 70s there were two manual trannys? One a straight 4 sp and one 3sp with over drive? What’s perfered?
 
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