[endneu913]

After reading a bit of what search found me, i felt it time to explain my issues and take a poll on where to go next. My pal Chris and I have been building up my 96 850 R wagon for the last several months, and finally installed a digital boost gauge about a month ago, and were kinda shocked at the low numbers. The car is pretty much at stock levels, solid 10psi range ( shift spikes are in the high 11s ) This was before and after some of my recent mods... heres my list:

96 850R wagon

IPD ecu ( should be in the high 15s psi- Proven 17psi in Chris 96 R)
3" True CAI ( cone filter sits below the battery tray )
MSD blaster ignition
IPD wires with new cap and rotors
3" Downpipe
Magnaflow Race cat ( ceramic substrate)
2.5" cat back with high flow "turbo style" muffler
TurboXs BOV

Here's what ive done:

Removed and inspected ALL charge pipes
Replaced all found vac leaks ( there were 2 minor ones) a quick starter fluid scan of the engine says no more..? )
Replaced both vac lines to the BCS
Replaced BCS with a junk yard one, then again one from our T5 wagon
Tightened up spring pressure on BOV ( it had a small amount of loose "play" under heavy throttle *not under load*
Hand felt tension on the wastegate actuator ( felt like decent spring, but perhaps need to replace? )

Next step IMO would be swapping the WA

Perhaps there are some more ideas out there?
I feel like ive read all the common low boost threads that a basic search could find, but i'm also noob-tastic.

Thanks super much!

-Grae

 

[soupandspoons]

Have you confirmed that the boost gauge is working properly? Is the "confirmed" 15-17 psi in your friends car measured with the same gauge?

 

[Johnr352]

Re: Low Boost on El R (endneu913)

Quote, originally posted by endneu913 »

Replaced all found vac leaks ( there were 2 minor ones) a quick starter fluid scan of the engine says no more..? ) -Grae

What is this process?

Quote, originally posted by endneu913 »

Next step IMO would be swapping the WA -Grae

And forgive me, what's this as well?

 

[endneu913]

Re: (soupandspoons)

Here is the boost gauge story. Installed it, realized it was a boost only gauge ( who knew they made these? lol ) ran it for a week, then sent it back for an exchange on a vac/boost guage, SO, that said, currently im basing my "low psi" opinion on the stock gauge. The stock gauge is designed to read the factory settings 9-10 psi, and this was corroborated by 2 things..

1) When I had my aftermarket gauge in there, and maxing 10lbs, the stock gauge would read at the end of the white band on the display.

2) On my buddy's wagon, ( same aftermarket gauge) when he's around 15-17psi, the stock gauge needle is sitting between the end of the white band and the temp sensor icon on the next gauge over...

That being said, my assumptions are based on the fact that my stock gauge isn't going past the end of the white band. Weak proof at best, I know, but I have to believe it for the moment.

We are both running Cyberdyne digital boost guages, they utilize the same part # sender, so I dont think im going out on a limb in saying that they are pretty much identical in sensitivity. Also, damn, his car feels fast

Also, WA : wastegate actuator... and the starter fluid test is simply, while the engine is running, spurting starter fluid around suspect vac leaks. If the car changes in idle speed then there's a vac leak nearby.

Thanks for the input guys, keep it coming!

 

[LloydDobler]

I'd say make sure your wastegate actuator is absolutely set properly. I'm not sure if the procedure is the same as it is on the newer cars, so ask your local Volvo specialist what the procedure is for your car specifically. There are many threads here about adjusting it, the procedure varies from car to car.

But I had the exact same problem and it was because my wastegate wasn't held shut and was dumping boost all the time.

 

[endneu913]

Hm, interesting, I did adjust the wastegate previously ( to get a quicker boost response) but that was in response to the lack of boost. It "feels" like its tight... but that doesn't account for much...

 

[endneu913]

Well, I popped off the DP this morning, it looks good and clean, so no issues there, it seats up well and doesn't look bend or burned up. So now for the even better new, I disconnected to vac line to the actuator and did a ginger test drive. With a small punch my tires were spitting rubber and the needle was almost to the temp gauge. Kinda scary. Drove home with no boost....

So, next step, replace the actuator itself or do a pressure test to verify its set properly?

Sounds like its not the BCS since ive swapped that multiple times.

 

[Oceans60R]

Re: (endneu913)

IIRC, each full turn of the wastegate rod was worth about 1/2lb boost.
I would start by adjusting that and see how much boost you can gain.
It may have been replaced and never set properly or just never set properly to begin with.
Adjust by shortening the wastegate rod.
I adjusted my old S70 T5 until the computer pulled fuel, then backed it off 1 full turn.

 

[endneu913]

As I tighten the wg arm, it seems to be raising the boost level. Ive been slowly tightening the arm, over the last few days... and im starting to think that it was just mal-adjusted to begin with. Im about to *educated guess* about 13lbs now.....

any thoughts?

 

[vlvman]

Re: (endneu913)

Carry on carefully. My stock R was running 10 psi 9.5 turns later it's at 15 psi. Volvo quality control sucks.

 

[endneu913]

hm, nice to know that the possibility exists. Over on VF, i got a great diagram on how to properly set it with a gauge and pump, and all the stock psi values. I could share it here if anyone had any interest.

 

[Johnr352]

Re: (endneu913)

Sure! Please share

 

[endneu913]

Re: (Johnr352)

http://img.photobucket.com/alb...M.jpg
http://img.photobucket.com/alb...M.jpg
http://img.photobucket.com/alb...M.jpg

 

[endneu913]

Well... I got a guage on there finally and i am making 15+ boost now, with the adjustments made to the WGA rod. So problem solved... perhaps?

I built a pump/gauge/ tester device, basically to pump air into the WGA, and measure how much psi at the same time. I set the WGA to "start" to open at 5psi, and it maxes out around 10 psi, which im told is the proper setting.

 

[endneu913]

Re: (endneu913)

Got my proper gauge now... Definitely hitting good boost levels, but all based on how tight my WGA rod is.... And its a bit spikey and just slightly unsteady... No major loss of boost, but it doesn't plane out and stay even, its kindy wobbly... like it hits 14, lags, shifts, hits 15, then drops back to 14... unreliably at best.

 

[soupandspoons]

Re: (endneu913)

How does that compare to your friend's car?

Is his a rock steady boost level? I'm just asking, because in your first post you mention his car hits boost of 15-17 psi and you're now indicating that you're seeing 14-15 psi.

Cheers,

J

 

[endneu913]

Re: (soupandspoons)

Well.. apples and pineapples.. Hes running a 16t turbo, im still with the 15g turbo, which im told has not so solid boost at best.....

If i toy with the WG rod and tighten it up, I will see 15+ PSI... but im waiting on my MBC to arrive to see if i can even out the issue but lengthening the rod for better all over wastegate functionality, and still maintain 15-16 psi...

It seems that im not hitting huge boost when I punch it, but more like i have to "build" up to 14-15 psi...

 

[Oceans60R]

Re: (endneu913)

Seems like you have adjusted it correctly.
I can't say exactly how much my 98 T5 used to run, probably 15-17 before fuel cutout. Once I backed it off so that there wasn't any fuel cutout, it was fine.

Be aware too many people focus on a gauge number reading instead of actual performance.

 

[endneu913]

Re: (Oceans60R)

Agreed, i think this digital gauge ha s a bit of lag-time as well...