Max Power?

[Viggen]

How much power can the ZF and LT take? Thinking about a swap but am unsure of the power levels through the stock boxes. Thanks.

 

[R_Lefebvre]

Which ZF, the 22 or 24? That's the first question. And they're usually going to be rated by torque, not horsepower.

 

[Viggen]

22 and about 300-305 tq?

 

[Lichen]

Didn't Homer Simpson once change his name to Max Power?

 

[SeaRubi]

use the zf4hp24's clutchpacks to rebuild your zf4hp22 ... that's what was recommended to me by a transmission shop. ymmv.

 

[R_Lefebvre]

Will they fit? The 24 is a little longer than the 22, presumably to fit the clutches?

 

[SeaRubi]

Will they fit? The 24 is a little longer than the 22, presumably to fit the clutches?

afaik, the rover 22/24 case is the same length. you're probably thinking of the tailshaft on bimmers or jags?

 

[R_Lefebvre]

No, the 24 is 15mm longer. Not a huge deal, but might cause the plates to not fit in the 22.

 

[SeaRubi]

No, the 24 is 15mm longer. Not a huge deal, but might cause the plates to not fit in the 22.

you can call the transmission shop i talked to and ask em, maybe? heh - :elkgrin:

 

[R_Lefebvre]

So they've done it before? I wonder why ZF bothered stretching the transmission if not needed.

 

[Yorker]

The LT-230 can take some pretty good torque, you can also upgrade or eliminate its differential to make it stronger too. The zf4hp22 on the other hand I wouldn't want to put too much more power than stock through.

 

[muskyman]

The LT-230 can take some pretty good torque, you can also upgrade or eliminate its differential to make it stronger too. The zf4hp22 on the other hand I wouldn't want to put too much more power than stock through.

really?

I was running 450 RWHP through one in my BMW 750 iL

they can be made really durable for sure, I am running the upgraded clutch packs in my 4hp22 in my disco.

 

[Yorker]

really?

I was running 450 RWHP through one in my BMW 750 iL

they can be made really durable for sure, I am running the upgraded clutch packs in my 4hp22 in my disco.

Sure they can be made stronger but in stock form they are nothing to write home about. If you are going to swap another engine in you may as well look at other trannies too imho.

 

[muskyman]

Sure they can be made stronger but in stock form they are nothing to write home about. If you are going to swap another engine in you may as well look at other trannies too imho.

I am not sure where you are getting this?

please link me to instances where people have toasted a 4hp22 from adding more power to the engine because I know of people that have bigger cams and headers and rimmer super chargers and such and have not had trans failures due to the increased power.

Auto trans fail from heat...keep them cool and they dont really fail that often. The torque convertor absorbs lots of the shock loads that would otherwise break components in a auto box. The TC takes those shock loads and slips and turns them into heat. So if you are adding more power and plan plan to use the trans hard look to increase the cooling of the unit and you then improve its ability to handle the increased power you are sending through it.

This isnt a rover thing its a car thing. ZF's are some of the best auto box's there are.

 

[rovertech]

No, the 24 is 15mm longer. Not a huge deal, but might cause the plates to not fit in the 22.

Overall length is increased not the case length. The difference is in the bell housing to accommodate a larger torque converter. The oil pump and other internals are different but case length is unchanged.