Upgrade just compressor wheel on 16t? (Posted for mikilla)

Post by **matthew1** » 20 May 2011, 08:54

Can I upgrade just the compressor wheel to a 16t? I found a blown 16t for $25 just wondering if I can and if I can run it on the stock tune at stock boost?

** Posted on behalf of MVS member mikilla **

Post by **jblackburn** » 20 May 2011, 08:57

On an 850? Sure, but it won't really do much for you on a stock tune - in fact, it may actually be slower to spool up like the S70 is compared to the 850.

The 15G's definitely got more to give if you want - go for a manual boost controller or a tune.

t5ftw · Post by **t5ftw** » 20 May 2011, 09:12

The excel chart from
http://www.wothrline.com/Cars_engine/HW ... harger.htm
shows it.

mikilla · Post by **mikilla** » 20 May 2011, 09:55

I plan on getting a chip in the near future I was just wondering if the turbo would be worth the $25. Right now I have a mbc set at about 10 how high can I turn it up? I read that if u don't tune it will burn a valve or somethig. Does the 16t have a bigger exhaust downpipe? I can get that too. Or should I get a compresser wheel for like a 18t and if i do that do i have to do anyhing to the compresser housig? Can I get a 18t with a speed tunning chip and maybe some bigger injectors and a safc and be ok?

Post by **jblackburn** » 20 May 2011, 09:58

Right now I have a mbc set at about 10 how high can I turn it up?

Fuel cut's around 12.

Does the 16t have a bigger exhaust downpipe?

No.

Can I get a 18t with a speed tunning chip and maybe some bigger injectors and a safc and be ok?

Sure. Don't do the 18t until you get a tune and do some exhaust upgrades, though. The tune is the important part - too much boost too low in the rev range, and you get bent rods.

Again, keep in mind that with going to a bigger turbo, you're going to lose some of that get-up-and go off the line. The S70's acceleration/tall first gear make it useless for trying to dart out in traffic quickly, but great for passing power from 30 mph on up.

Post by **matthew1** » 20 May 2011, 12:16

jblackburn wrote:Again, keep in mind that with going to a bigger turbo, you're going to lose some of that get-up-and go off the line. The S70's acceleration/tall first gear make it useless for trying to dart out in traffic quickly, but great for passing power from 30 mph on up.

Exactly why Volvo did 2 things in the late 1990s: made the turbo smaller on the GLT cars because smaller turbos have less mass, and thus spin up faster -- think American driving as to why they did this, not Autobahn. Also, they gave the S80 twin turbos, both small to aid stoplight performance, but good at higher speeds because two turbos push more air.

Volvo is still using the twin-turbo setup to this day because it provides the best of both worlds. AFAIK, nobody has put two turbos on a pre-P2 850/S70/V70 car. It would be a nightmare.

Actually Volvo did three things: they implemented 5-speed auto transmissions in S70/V70 cars (AW55-50 ... 5sp auto, began in 2000, but some 2000 S70/V70s didn't get it, owners simply have to be aware of which they have). The first gear is lower, the rest are unchanged. At least that's how it is on my 2004 V70 R. Highway cruise at the same speed is the same RPM (gear 5) as my 1997 850 (gear 4).

Post by **matthew1** » 20 May 2011, 12:19

See more about Volvo transmissions on our Volvo Transmissions Guide.

Post by **jblackburn** » 20 May 2011, 12:38

That graph really does tell a lot of the story. I think they also realized after 1998 "holy crap, this thing needs more low-end power from the 16t!"

The IPD turbo control valve and a turn and a half on the wastegate helped me a bit with that - it's got a decent amount of power from about 2000 RPM on up now, but it's still nothing like a V6 or LPT engine, and you're not going to win any races from a stoplight.

1999 saw a change to a different turbo exhaust outlet (an angle flange opposed to the straight one on the 1996-1998 cars) that helps it spool a bit faster, and the electronic throttle body and variable valve timing on the exhaust cam helps it get off the line a bit faster by optimizing the amount of air metered into the engine. If I floor mine from a dead stop, it's definitely slower than if I give it about 75% throttle til the turbo comes up.

The reality of it is, when you're dealing with an engine still only 2.3 liters, you're just not going to have a lot of torque down-low, and the things are actually quite fast once you get going!