RPO B4U code performance dash cluster?

[crossy's son]

I want one real bad for my 1991. It has a 110 mph speedo in it with a 6000 RPM tach. Is there a place that sells them? Are they available from GM? Anyabody have one? Im positive they came in 454SS trucks. Hmm...need a wrecked 454SS . thanks. Brandon

[tommie]

I have read some stuff about these on other boards. From what I remember 88-91 have the same plug for the instrument cluster and use a DRAC inside the instrument cluster. 92-up have a different style plug for the instrument cluster and use an external drac. The only yearthat a tach dash was made that is plug and play for 88-91 was offered for 91 trucks. search on fullsize chevy . com i think that is were i found out all of this. the drac in the 88-91 cluster is "burned in" at the factory and if you swap to a different truck, with different trans, rear end gears, tire size, you have to buy a kit from gm to erase the factory burn and then use the supplied chip for your application. I have a 91' tach dash from a 1/2 ton 2wd 350/700r4 3.42 gear. I have though about putting it in my truck (90' 350/700r4 3.08 gear) I would have to buy the kit from gm to change the settings in the cluster, i think the kit is around $50-60, I just have not had the extra money to do it yet.

A lot of people change to the 92-94 tach cluster and use the 92-94 Drac and i have seen some instructions on the net about how to make this drac reprogrammable at home with the help of radio shack.

http://www.fullsizechevy.com/forums/...h+dash+swap+91

[tommie]

Also,

I do remember that some of the tach dashes had different top mph readings, search the net and you can prob find that answer to this one also..

whoo hoo!!! 400 posts!!!!