I have a 00 em1 what has a d-series engine in it. YES, its an em1 and YES I know it is supposed to have a b16 in it and NO I didn't get ripped off and didn't pay to much for it, blah blah.

Anyway, it had a 1998 hx 5-speed cluster in it (that was the donor car after it was stolen - never turned into insurance so title is clean) and I found an original si gauge cluster for it. Everything was working fine on the old one and when I installed the new si cluster, the tach readings are way different. The si cluster idles about 200 rpm higher, but gets progressively worse as it climbs in rpms compared to the old cluster. With the old cluster, I would cruise about 30 mph in 4th gear at about 1900 rpms and the new si cluster has the rpms at about 2500. Anybody got a idea of WTF is going on?

 

i had a dx and put in a si cluster and it works perfectly fine.

 

Well, this one is not working.

 

OEM tachs are known to be inaccurate especially from one OEM tach to another. Your cluster is working fine. If you are worried about the actual RPMs, get a RevSpeed or VAFC meter if you don't want a large aftermarket tach.