tcu

[blazedealh91]

if i stuck a tcu frome a prelude on my stock f22 tranny will it work ??
i have a p15 out of a 96 prelude

[Racer_XXX]

It should work. My sister's boyfriend used one in his with no problems.

[blazedealh91]

It should work. My sister's boyfriend used one in his with no problems.

lol i have the tranny that goes with it but dont have the time to swap it out right now do u know about how long it would take to swap out the tranny

[Racer_XXX]

I'd dedicate a Saturday afternoon to it. Me and my buddy pulled mine out over a couple days, just working on it when we both had some free time

[deevergote]

I thought OBD2 cars had the TCU integrated into the ECU...


Anyway, if the transmission fits in your car, the TCU will work. However, if you're putting this on a relatively stock F22A, you're going to be revving out of your powerband... you won't gaining anything but additional wear and tear on your old motor.


As for how long it takes... that depends on you. Read a manual, and figure out how comfortable you are with the process. If you estimate 6 hours, expect to spend 12. Be sure to prepare yourself with the proper fluids, and get ready to replace any parts that you damage (ball joints... if you rip a boot, replace the joint. Axles... if you separate a joint, replace the axle.)

[blazedealh91]

I thought OBD2 cars had the TCU integrated into the ECU...


Anyway, if the transmission fits in your car, the TCU will work. However, if you're putting this on a relatively stock F22A, you're going to be revving out of your powerband... you won't gaining anything but additional wear and tear on your old motor.


As for how long it takes... that depends on you. Read a manual, and figure out how comfortable you are with the process. If you estimate 6 hours, expect to spend 12. Be sure to prepare yourself with the proper fluids, and get ready to replace any parts that you damage (ball joints... if you rip a boot, replace the joint. Axles... if you separate a joint, replace the axle.)

idk the tranny came out of a 96 prelude auto (mp1a) the dude gave me a tcu

[deevergote]

96 was a weird year... the last year of the 4th gen Prelude, but the first year of OBD2. I can't find anything conclusive, so I suppose all we can do is assume that it is indeed a 96. Not that it really matters.

[Rome702]

if i stuck a tcu frome a prelude on my stock f22 tranny will it work ??
i have a p15 out of a 96 prelude

The obd2 ecu has the tcu built in, but the p15 is off the prelude s which is an f22 motor. you wont have any problems installing the tcu and it will work just fine. the only way you would be over revving your power pand is if you used a tcu from a vtec prelude. If it comes from the prelude s (P15) or prelude si (P14), you will be fine.

[blazedealh91]

The obd2 ecu has the tcu built in, but the p15 is off the prelude s which is an f22 motor. you wont have any problems installing the tcu and it will work just fine. the only way you would be over revving your power pand is if you used a tcu from a vtec prelude. If it comes from the prelude s (P15) or prelude si (P14), you will be fine.

it came out of a si non vtec

[deevergote]

The Prelude S with the F22 came with a P12 ECU.

The Prelude Si with the H23 came with the P14 ECU.




HOWEVER, this thread is asking about the P15 TCU. The transmission computer, not the engine computer. That is the P15 in the Prelude Si.

I still can't find anything suggesting that it'd be from an OBD2 Prelude... regardless, it IS a TCU from a Prelude Si, so that's all that matters. It will raise your shift points, regardless of your transmission. That isn't necessarily a good thing, but yes, it will work.

[blazedealh91]

The Prelude S with the F22 came with a P12 ECU.

The Prelude Si with the H23 came with the P14 ECU.




HOWEVER, this thread is asking about the P15 TCU. The transmission computer, not the engine computer. That is the P15 in the Prelude Si.

I still can't find anything suggesting that it'd be from an OBD2 Prelude... regardless, it IS a TCU from a Prelude Si, so that's all that matters. It will raise your shift points, regardless of your transmission. That isn't necessarily a good thing, but yes, it will work.

i thought the h series had shorter gears wouldnt that mean shifts at lower rpms

[deevergote]

The TCU has no idea what transmission you have. It only cares about shift points. The H series has a higher redline, and a higher powerband... so it revs higher.

[Rome702]

The TCU has no idea what transmission you have. It only cares about shift points. The H series has a higher redline, and a higher powerband... so it revs higher.

The h22 has a higher redline not the h23. plus the tcu works in collaberation with the ecu, so it wont shift unless the ecu says the rpms are high enough. The h22 has a really short gearing ratio, while the h23 has a longer gearing ratio... leaving the f22 tranny to sit in the middle. You should not have any type of change using the prelude tcu. I did it before i did my 5speed conversion and didnt notice any difference in the shift. Now i have a bunch of cb7 tcu's but not sure how i ended up with them all.

BTW... that tcu is from the prelude s which came with the f22. If you look at his picture of the tcu it says us lot number p12

The powerband has to do with the tranny not the tcu and the redline has to do with the ecu/tcu combination.

[deevergote]

The H23 transmission's gearing is between that of the H22 and F22. It is shorter than the F22's gearing.

The H23 revs higher than the F22, but only by 200 rpm.

The powerband has nothing to do with the transmission. It is where in the RPM range that the engine makes power. The transmission (and the electronics that dictate when it shifts) only determines how high the engine will rev before shifting, and how low the RPM will be in the next gear. The ECU doesn't tell the TCU to shift, nor does it interpret the RPM... RPM is physical, not something interpreted by a computer. It is a constant.

If your gearing isn't suited to your engine's powerband, and your TCU is telling the transmission to shift too early or too late, you're going to be driving in a dead zone. In order to be effective performance-wise, they need to be properly matched.

As I said, it won't hurt anything, but it may not do anything but change the way things feel when driving your car. And with the H23 TCU, probably not a whole lot.

[deevergote]

If you look at his picture of the tcu it says us lot number p12

Yeah, and the F22A6 head is stamped PT3. Your point?