# RB20 swap, RPM/tach problems



## TerenceN425 (Jan 1, 2007)

I just recently dropped an rb20det into my 91' 240sx se about 1 1/2 months ago, the swap was done by me and three friends, clean, no cheap/short cuts. Everything runs smoothly. BUT...my stock cluster, the RPM's read in correctly. it reads almost 2/3 off the acutal RPM. I havent had anytime to work my car since the swap, but now that schools about to start I can get back into my shop class and fix the RPM problem.

If the stock tach is the problem, as in not reading the rpms correctly, what kind of tach will I need? I need an dash tach that will replace the my current stock RPM's. Anybody know a place that seels JDM rb tachs or is ebay the only way to go?


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## TerenceN425 (Jan 1, 2007)

do I have to find a jdm rb tach and replace my stock tach?


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## Dustin (Dec 14, 2003)

i haven't heard of this, but i'd assume it's got something to do with where you're getting your tach signal from. i'd personally run it off of the ECU, but i'm not sure which wire it is or anything, you'd be better of searching for the answer, because i'm sure there's something to help you.


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## 180SX-X (Sep 21, 2003)

is your wiring right? well..the signal might be different, not sure..i say get a HUD, go all out
!!no, im kidding..an rb tach wont fit in your car..cant you just buy a new tach, like from auto meter, and put it on the steering colum in front of the old one? it doesnt have to be a big 3-5" tach, they sell 2" tachs as well..


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