Interesting HU Install and Findings (RFX8240 in Trans Am)

10+ year member

Not Quite a Noob
This has easily been the most complicated head unit install I've ever tackled, just because it was hard to make it look like I wanted it to look. Very rewarding now that its done though. Pics to come tomorrow, too late to get pics, wont show up so well in the dark. Onto the whole ordeal...

I decided to run the RFX8240 in the Trans Am over the Clarion DXZ835MP, and it presented some problems to say the least. The 8240 is an ISO mount unit and GM dashes are DIN mount, so I had to get a little creative. I started out with a Metra flush mount kit for my car and I scavenged the DIN mounting cage off of the Clarion 835MP. Mounted the cage to the mounting kit then bored out some extra holes to run screws through and into the sides of the 8240. Iso mounting allowed me to drop the 8240 back into my dash a bit further than it would normally go, so that added some to the looks department. It barely fit because of rearward clearance but I got it in there. Onto problem numero dos...

The 8240 doesn't have a removeable faceplate, and I'm paranoid about theft even with tinted windows and an alarm, so I had to come up with something. I spent all day yesterday dismantling my old stock tape player and epoxying the buttons back onto the face to act as a dummy panel that looked like my stock tape player. Mission accomplished. Where I failed was the rotary volume knob on the 8240 sticks out too far and all my work was for naught. The back of the dummy faceplate wouldn't clear the volume knob, and there was no way it would ever work. Fast forward to today after a trip to WalMart's craft department. Got some black felt and a wooden dowel. Cut up some thick cardboard and wrapped it in black duct tape to add to the sturdiness of it, then I attached a dowel frame to the back of that via thumb tacks. Then I was stuck. I didnt have any Super 77 here, didnt want to go buy any, and couldnt figure out what to do. My great g/f mentioned that I had a hot glue gun in my toolbox that she saw a few days back looking for a screwdriver, so we grab it up and she goes to work on hot gluing the felt to the cardboard/dowel plate. Does a great job on it and we throw on a little tab to make the friction fitted cover plate easier to take off. Out to the car to test fit shows that I didn't trim out enough cardboard for the 8240's volume knob. That **** volume knob has been the angst of my existance for the past two days. So I do a little reworking on the cardboard from the backside and it fits right in. Now when you look at it with the cover plate on you just see my HVAC controls, the little snap on GM trim ring that trims it all off, and a flat panel all the way across. When the hideaway panel is removed the silver faced 8240 looks so clean in the dash and sets off my silver faced gauges perfectly. Much thanks to my g/f for helping me out on the crafty part of the install. Guess it pays to have a g/f handy with the hot glue gun around at times.

Interesting things to note:

Clarion 835MP has 4V preamp outputs and max volume of 33, and to get decent output with my gain settings I hit around 26. I thought the Rockford unit had 5V preamps, but thats the 8250s only, 8240s got 2V preamps. Funny thing though, max volume is close to Clarion at 32, but without adjusting the gains at all, 20 on the RFX equals roughly the same output as the Clarion does. Maybe they scale their volume tables differently, but it would seem that the Rockford unit's 2V preamps pack a bit more punch than the Clarion's 4V preamps do. Just something I found interesting //

thanks about posting that info on the volume level on the clarions, i was considering getting one but now i think i will stick with alpine now that i have sold my pioneer. i was considering doing the same thing with my pioneer in my intrepid, but the faceplate was removable. btw //


Intersting..... congrats on getting it to work

Sounds like a fair amount of work ... but well worth it, in my opinion.

If I'm ever in that position, I might have to try and do the same //

- Steve

No one is currently typing a reply...
Old Thread: Please note, there have been no replies in this thread for over 3 years!
Content in this thread may no longer be relevant.
Perhaps it would be better to start a new thread instead.

About this thread


10+ year member
Not Quite a Noob
Thread starter
Nashville, TN
Start date
Who Replied
Last reply date
Last reply from


    Jul 19, 2024
  • 0
  • 0


    Jul 19, 2024
  • 0
  • 0

New threads