Boost Gauge

goober4321 · Post by **goober4321** » 17 Jul 2008, 18:28

I want to add in an aftermarket boost gauge. Can someone give me a step by step as to what line I can use. It is a 97 850T.

Post by **MadeInJapan** » 17 Jul 2008, 19:13

Most boost gauges come with the "line." If you have one already and don't know where to attach it, it is very simple...any open nipple at the vacuum tree (located under the throttle cable cover) will work. There should be a couple...just take the stopper cap off and connect the line to it. If this didn't answer your question, then please post back.

goober4321 · Post by **goober4321** » 17 Jul 2008, 20:20

But using the tree does this make the boost gauge accurate?

Post by **MadeInJapan** » 17 Jul 2008, 20:54

Yes....most accurate.

goober4321 · Post by **goober4321** » 18 Jul 2008, 06:02

OK thanks alot

Nick'sTurbowagon · Post by **Nick'sTurbowagon** » 18 Jul 2008, 09:30

I added a Autometer sports comp boost/vac gauge to my 1996 850 turbowagon.

Did not have to go into the engine compartment as there is already a boost gauge line coming from the engine compartment to the OEM dash gauge.

Take off the lower dash cover located under the driver's side steering wheel, You should be able to spot the nylon line going up to the OEM gauge, Use the "T" supplied with the new gauge. I mounted the new gauge in an A pillar pod.

You will also need to tap in the new gauge electric connections at the lighting switch.

There good instructions at Volvo Speed

Post by **MadeInJapan** » 18 Jul 2008, 22:18

Ah...forgot that unlike the S70, 850's have a boost gauge line running into the instrument panel. By all means use what's there...a lot less hassle.

Post by **matthew1** » 19 Jul 2008, 12:43

Just thinking "out loud" here...

One could calibrate the 850 gauge after (temporarily) installing an aftermarket gauge, by cross-referencing readings between the two. Adding markings to the in-dash gauge would be tricky. I'd probably find a graphic artist in town to take the instrument cluster to after you've determined where boost readings should go.

Overall, this would be a fun but very involved project. For the 850 nut. I bet somebody out there has done it.

Good thread.

Post by **MadeInJapan** » 19 Jul 2008, 13:48

Matthew- good idea but one size doesn't fit all on this. I've heard of some of those needles that go all the way to the right where they can go no further...on a chipped or modded car this is even more so. Each individual would have to do this to their own car and it would only be beneficial on those that don't top out on their gauge.

goober4321 · Post by **goober4321** » 20 Jul 2008, 07:51

I was thinking along those lines as well. If I ever get the PCM upgrade I would not be able to totally get accurate boost reading from the factory gauge if I were to put reference marks on it. Although it is a good idea just not appropriate in all circumstances. Can anyone guide me in the right direction though on tuning through your laptop (hopefully free).