I have a 1986 Iroc with an 85Mph speedo. I know that there are 145mph speedo's for a couple hundred $$$ for sale; BUT, is it possible that a 120 mph speedo would work? If so, what year would fit my car. Maybe a 120 would be cheaper? I've heard of complete clusters with bad tach,,,easy fix... I hate this 85 mph cluster, the needle always bounces,,i hate that. Come-on,,,an 85 mph speedo for an IROC?? WTF... What were they thinkin..

I bet if you are patient and keep an eye on the board, craigslist, etc, you will find one for a decent price. Thirdgen ranch has one for $125 right now I think.

Yep, we've got one for $125. Here's a link if you're interested.

http://thirdgenranch.com/-strse-668/...MPH/Detail.bok

Otherwise, you can use a 120 MPH cluster as well.

Any mechanical speedo head (120 or 140) will swap in--and I'd swap only the speedo head to avoid possible electrical gremlins. If the needle is bouncing, the problem could lie elsewhere. Check the following link for more info:

http://www.thirdgen.org/techboard/in...eedo-woes.html (Reasons for Mechanical Speedo Woes)

JamesC

Thank you gentlemen
Really good responses.

The 115 speedos can always be found cheaper,..... even the V6's 'base' Speedo cluster was the 115 after the mid 80's so there are a lot more 115's out for sale there than 145's !

Like James said; If your not having any trouble with any of your current guages or other cluster functions than your best bet is to swap just the speedometer head !

About the only cool thing about the pre-86 speedometerss is that I can claim that I have my Speedo needle "burried" every day of the week !