ZF 8-speed swaps. Next big thing?

Not exactly the only thing changed.... Clogged injectors and a sloppy rear end later..

Zip ties for the flex lines...

Nice that they have the electronics working on the box.

Now we just have to stop all the chev ppl taking all the dodge boxes.... They are in bmws too ffs

Sure they are in BMW's, ZF8 first use was in a bmw 7 series. ZF and BMW are both German. Trans doesn't even need to take a boat ride to end up in their cars

they are in several vehicles but the bell housing is different. There is a post here somewhere where a guy made one to go on a 440(lot of machine work). Hopefully somebody will come up with a adapter/s to go on MOPAR ENGINE (other than a hellcat).

They should bolt right up to a small block, it would need some kind of flex plate adapter but the small block shares the same bellhousing pattern as the G3 hemi does. There might be issues with the starter mounting though I don't know.

Pretty sure the ZF90 (hellcat) version was first designed to be used on those twin turbo V12 6500lb Rolls Royces and Bentleys. If those weren't on the shelf the hellcat probably wouldn't have been able to happen

Are those tranny suppose to be good for some drag and heavy street with 700+ HP motors?

link

Lots of supercharged 800-1000+ HP Hemis running FAST in heavy late model Dodge muscle cars and Jeep SRT 4WDs at 4500lbs.

Usually,past 800 WHP in heavy cars the trans needs a few mods, lots of 8 spd specialists around building them. They still use the OEM style torque management between shifts. I imagine this could be achieved with a programmable timing control unit to pull timing between shifts.

The software/electronics for the swap now exists and are sorted; adapters are available to allow it to bolt up to a BBM. If you have a modded trans tunnel and eliminated the torsion bars with a coil overs as I have the swap is way easier, but many are'nt willing to do that to their rides so that is the deal killer.

I've seen converters to 4500 rpm stall but if required, I have'nt seen anything with more stall available as yet.

I'm looking into possibly going down this path in the future. Changing out the gears in the Dana in my car to 3.23s with a 30" tire would be work and it'll be closer to a Hellcat's 3.07 rear gear option with the tire OD. With a 4.71 first gear you'll be ripping through the gears like a Hellcat hence the low number final drive ratio with a double OD in 7th and 8th to boot.

Info from the Hellcat forum:

1st -- 4.714
2nd -- 3.143
3rd -- 2.106
4th -- 1.667
5th -- 1.285
6th -- 1.000
7th -- 0.839
8th -- 0.667

Hellcat 2.62 final drive
( 1st x Final drive )
4.714 x 2.62 = 12.35068 SLR

(2nd gear x Final Drive )
3.143 x 2.62 = 8.23466


Old NAG1
( 1st x Final )
3.588 x 3.06 = 10.97928


727/904 with various gear ratios

( 1st x final drive )
2.45 x 4.10 = 10.045
2.45 x 4.56 = 11.172 ( Close to NAG1 )
2.45 x 4.88 = 11.956

4.88s and still not there yet SLR wise.

2.45 x 5.13 final drive = 12.5685


Hellcat vs Old School
To compare a 1st gear start - Your final drive ratio would be around 5.04 with a 28" tire
To compare a 2nd gear start - Your final drive ratio would be around 3.36 with a 28" tire


To complete the swap, you'd have to use an OEM style Hellcat shifter, aftermarket shifter handles are available to make it look like an aftermarket 3 spd shifter.

I think it would be awesome if I could get the appropriate converter sorted out.

Lots to consider, it ain't a straightforward swap but it can be done.

Thats pretty cool for sure. Problem is too many will believe their car would be that much faster by simply swapping in an 8 speed. Some combos will benefit , and some wont make much a difference at all. To many variables. I know of a guy who swapped out a 46re to an 8 speed and gained a little over a.15 in the 1/4 in his hemi powered Dakota. Its an awesome trans though for sure.

Over the NAG1 it was said the biggest gains were from 2nd to 5th with the ZF, and thats over a 5-speed. Could be pretty big over 3 spd, or a glide.

The advertising that the 8 speed is 98% efficient in every gear is amazing to me, especially the high ratio 1st and 2nd gears

That does sound outrageous but if you have ever driven a vehicle with these trans they work soooo well. We have had a Durango R/T and a Grand Cherokee with the 8 speed. I like to leave the little indicator on the dash that shows you what gear it is in, its interesting the choices it makes. When in "sport mode" they shift firm and quick, in regular mode you seldom even notice. FWIW my wife's Grand Cherokee picks up a tenth in sport mode lol.

JVX transmissions has the adapter ready for the SB and BB Sound German Automotive has the controller

how much tunnel work is required for this swap where a 727 lives now ?

Show me where it says anything about the ZF8.
link

Call John Vinson @JVX 901-274-7248 he just starting making these they are not listed on his site. John is semi retired and while he and I were talking about a 727 he was building for me. I asked about doing a 8HP70 adapter he said if there was interest he could do it. So I put the word out and he got enough interest and he's doing them now. He has BB and SB kit. Russell Drake at Sound German Automotive can help with the controller. I have my adapter kit but not ready to start the conversion yet. There are some SB LA conversions done I have heard. Go on facebook page LA-B/RB Engines to 8hp70-90-NAG1. There is more info there.

What is the first and second gear ratios in theat transmission? I remember reading that the 8 speed in my 2014 truck had lower first and second gears ratios than the first gear in the previously used 6 speed. It would be pretty cool to go from a 4.10 to a 3.55 and keep the SLR in the same range, then have the OD to boot.

1st is 4.71.

See LAD 524's post above for the rest.

Kevin

There is quite a bit to this conversion. Adapter kit TCM and Harness and HP tuner and s TPS if you running carburetor. Has for HP/TQ there are 900-1000 HP cars using HP70. More HP than that probably better to do the HP90. My deal is a 512 with 640HP/670TQ so I'm good. Russell Drake at Sound German Automotive can help with everything you need to do this. He's got stock shifters paddle shifters TCM harness and remote tuning ability. Also on my deal I gonna have to send my HP70 TCM in to Russell to program the trans itself. I'm gonna do mine with a 1320 calibration. So I will have 3 modes the Track mode=Trans Brake Sport= Manual shift and Street mode= Full auto. So I'm gonna need the paddle shifter plus a stock shifter and mode selector. I will confirm all this with Russell and make sure I'm telling this right. I will let you guys know

UPDATE Talked with Russell. Everything above is doable. But he said I could hold off on the TB. I can always upgrade to the TB feature later. He says TB works well but didn't know if it wouldn't be just as good without for what I'm doing. So I'm leaning now more to just to all time Track mode without the TB.

What ZF8 is the kit based off of since there are so many different ones(bell housings)?

The strategy on the newer transmissions is to dump timing for fraction of second between shifts to help the transmission live at high power levels, so are they offering timing control with the swap modules?
It'd be nice if someone would start making adapter packages for 4wd applications that would allow it to be bolted up to an np 205 transfer case. The 205 is the probably the toughest transfer case but doesn't
have a deep reduction like the 208-271 range. Having deep first gears of the newer trans would make for good crawl ratio's with a 205. Need a dedicated big block bell as well. I was looking at an 8hp swap for
my rotary car, but it looks like a sequential manual still outperforms the newer autos on a road course, probably because of the faster and full power shifting.

That's done primarily for shift feel. The newer transmissions have so much rotational inertia in them, if you don't manage torque during shifts it feels very odd- you get pushes through the driveline that are unnerving, it feels like extra acceleration through the gear, which also can upset the car. Pulling timing settles it out.

well i guess that answers that question............

Your answer is in this thread, "It was close to the tunnel"

thanks for that link.
answered a lot of my questions.

In the tuning discussions on the Euro pages, I was reading the opposite, they are lightweight internally which adds to their efficiency. They use torque management on the upshift to manage slip in between shifts, and they need throttle blip on the downshifts to save the clutches. Apparently the HTG GPU can do just about all that's needed to run that transmission.

It's a tradeoff of how quickly you can apply the clutches vs. shift feel. You can get it to live without the torque management but it won't feel good at all.

Car 8HP70 driver side starter. I like the 2018 and up HPs

JVX adapter and 2015 RAM 8HP70 behind a 1971 413-1 "industrial"/RV engine.
Trans re-flash still needed to match the EcoDeisel power curve, which is almost identical.
Challenger shifter with fabbed adapter plate for the RV dash.

Is that spray foam everywhere underneath?

Ya, 4" or so. I added foil over the trans in case of high heat.
First owners bought it in CO and lived in MT

I'd love to have an 8 speed in my '65 Coronet but at this point in time I'm not going to go thru the work to make it happen. Way too many things to change, custom build, design, fabricate, etc.

Tunnel mod was done to allow for this when I built my car back in 2014.






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If the AUD was'nt so crap against the greenback I'd already have done the swap

So the built 727 will have to do.....