Is my gearing messed up? (1JZ W58 Low Speeds, High RPMS! - 5speed SC owners plz come)
#31
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^^ This. I didn't realize you had a 1JZ swap or I misread. You do need to modify the tach signal either with that MSD box or by modifying the gauge on the back of the cluster. Personally, I'd use the MSD *if* it does the same thing.
Here's a guess: the tach must have worked semi-accurately with the auto transmission (you swapped in the R154 yourself, right?) but something changed or was removed on the electronic side once the automatic was removed, perhaps because of an electrical signal the ECU needs from the automatic transmission or a factory difference in how Toyota engineered the automatic and manual 1JZ tachs to get their correct signal pulses. Are you using a 1JZ automatic ECU that came with your swapped car or did you switch to a 1JZ manual ECU?
Regardless, try the MSD. If that solves your issue then you're golden.
Here's a guess: the tach must have worked semi-accurately with the auto transmission (you swapped in the R154 yourself, right?) but something changed or was removed on the electronic side once the automatic was removed, perhaps because of an electrical signal the ECU needs from the automatic transmission or a factory difference in how Toyota engineered the automatic and manual 1JZ tachs to get their correct signal pulses. Are you using a 1JZ automatic ECU that came with your swapped car or did you switch to a 1JZ manual ECU?
Regardless, try the MSD. If that solves your issue then you're golden.
When my car is off, first of all. The tach RPMs are sitting at 400-500 when the car is off. So already I assume someone *****ed with my tach before I bought the car.
I am using a 1JZ automatic ECU
Using a W58 transmission.
Blk&blu explained to me that my tach is reading wrong, and I honestly agree with him. As far as updates, I haven't been able to really get dirty and work on tearing apart the dashboard or considering opening up the new MSD tach adapter. I'll chime in whenever I get results.
#32
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Roger knows his stuff on here. He is like EF Hutton, when he speaks, people listen, like the old commercial used to say. I agree with him also, since you now noticed your tach is sitting in that range while off.
#34
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I was hoping that some of the older guys would remember that old stupid commercial. Yes Roger I am knocking on 40. Man it flies by.
Your welcome on the props. You have always went above and beyond the call of duty when I call and ask some questions. It doesn't go unnoticed.
Your welcome on the props. You have always went above and beyond the call of duty when I call and ask some questions. It doesn't go unnoticed.
#35
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I just looked up the commercials you both mentioned. I love that stuff. Classic cheesy 70's "word of mouth" adverts. I wouldn't be surprised if the same agency did the "time to make the donuts" campaign ![Wink](https://www.clublexus.com/forums/images/smilies/wink.gif)
Anyway, OP, You don't need to tear apart the entire dash. There are two videos that talk about replacing your water temp or fuel gauge but they can be used to approximate getting to your speedo or tach as well (below).
You may have to replace or have the tach repaired, otherwise for a 1JZ swap regardless of the ECU type you have to use the MSD box or the 1JZ tach mod listed in a DIY on the forums. The last one involves soldering.
![Wink](https://www.clublexus.com/forums/images/smilies/wink.gif)
Anyway, OP, You don't need to tear apart the entire dash. There are two videos that talk about replacing your water temp or fuel gauge but they can be used to approximate getting to your speedo or tach as well (below).
You may have to replace or have the tach repaired, otherwise for a 1JZ swap regardless of the ECU type you have to use the MSD box or the 1JZ tach mod listed in a DIY on the forums. The last one involves soldering.
#36
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hmm 500 rpm's off may have been good to mention earlier =)
as long as the dial still sweeps smoothly you may be able to recalibrate it.
if it hangs up or catches in places, you probably need a new tacho board, both the speedo board and tach board are detachable from the main cluster, I have broken one before myself, just make sure to get one from an sc3.
as long as the dial still sweeps smoothly you may be able to recalibrate it.
if it hangs up or catches in places, you probably need a new tacho board, both the speedo board and tach board are detachable from the main cluster, I have broken one before myself, just make sure to get one from an sc3.
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