Volvo Compressor Housing Modification
From the Performance Forum:
Q: “Is it possible to change the 16t Volvo compressor housing wheel to a 18t compressor wheel without having to modify the 16t Compressor Housing ? I recently acquired a 16t turbo off an S70. I have the rebuild kit ordered and want to know if I can just upgrade the wheel while I have it apart?”
Bored out the compressor housing to fit the bigger 18t wheel. Very time consuming and requires some patience. It took me two days to get it just right with the 2mm gap between the housing and the wheel. I used a die grinder and some sanding paddles.
After I took out the 15g out of my car I found that it had a lot of shaft play and was definitely ready to be replaced. So I installed the 18t with no problems and it started fine. What a relief! When I went to take it for a drive to make sure everything was working right I noticed I was only boosting to around 8-9 psi with my boost controller turned all the way up. Needless to say I was not happy and headed back to the garage.
After checking for leaks(coolant/oil) and finding none I moved on to troubleshoot the boost problem. Low and behold I had found that I missed putting the cbv hose back on the nipple. I love simple fixes. Slapped it back on and took it for another test drive. Whoa!!!!!! Holy $&@? I was boosting really hard, around 19-20 on my boost gauge. Which is weird because I thought there was a fuel cutoff at 15.5? I had no fuel cut, although I let off early when I saw the boost get that high. So I adjusted my mbc to a reasonable 13-14. It boosts right to 14 and holds it to redline with no boost fade. My other turbo was getting boost fade bad because of a cracked and deteriorating cbv diaphragm. I love it. All in all this turbo cost me $155. A $65 junkyard 16t out of an s70 a $55 eBay rebuild kit and a $35 18t compressor wheel. Oh and you can’t forget the your time, but for me I love wrenching on my car so that’s fine with me. I need to get a tune so I can use the turbo to it’s potential but right now it’s a nice upgrade. I did notice a little more lag off the line but nothing to noticeable. Now to rebuild my old turbo, see some mpg figures and see what I run at the strip now!
I will update when I get some numbers.