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2.3 NA regina to 2.3 Turbo LH2.4 motor swap

I pulled the MBC today. I'm getting around 16L/100km on 12 PSI, pulls like a rocket though I absolutely love driving it. Gonna go two weeks and see what I get on stock boost. It's no fun driving, can't swing the rear end out anymore but hopefully I'll get better fuel economy. I'm in Christmas broke season so gotta be smart with money and fuel.

I might consider changing out the wastegate as I don't like full boost at partial throttle.
 
I've been running stock boost since the beginning of winter (for safety hehe) and I've been getting the same average 16L/100km (14.7 MPG) and I'm kinda surprised I was expecting a little better. I've been driving it gently and probably 20% highway 80% city. I fill up every second wednesday and by the time saturday rolls around I'm already hovering around the halfway mark on the gauge after only 150 km (93 miles), I've had to top the tank off early annoyingly since I like only filling up on payday.

No vacuum leaks, no brake drag, all tires aired up nicely, no stored codes, no exhaust leaks, I just tested to o2 sensor and it is working correctly on the scope, spark plugs gapped and look good. One thing I've noticed just driving it and looking at the vacuum/boost gauge is that to accerate even modestly I'm almost touching the middle of the gauge, I'm always shooting up into boost during a drive even though I'm driving normally.
 
I've been running stock boost since the beginning of winter (for safety hehe) and I've been getting the same average 16L/100km (14.7 MPG) and I'm kinda surprised I was expecting a little better. I've been driving it gently and probably 20% highway 80% city. I fill up every second wednesday and by the time saturday rolls around I'm already hovering around the halfway mark on the gauge after only 150 km (93 miles), I've had to top the tank off early annoyingly since I like only filling up on payday.
That sounds exceedingly bad. During the summer I was averaging ~25-26 MPG combined, although I have a manual.

Your numbers are reminiscent of what my car was doing with a dirty cone air filter and a wasted MAF. Did you use a stock turbo airbox when you swapped to the turbo motor?
 
That sounds exceedingly bad. During the summer I was averaging ~25-26 MPG combined, although I have a manual.

Your numbers are reminiscent of what my car was doing with a dirty cone air filter and a wasted MAF. Did you use a stock turbo airbox when you swapped to the turbo motor?
Yes I am using the stock air filter box and an OEM spec filter. I removed the baffling and that big foam bit below so I can hear the CBV other than that it's all stock.
 
I'm betting you need a driver mod. Always shooting up into boost is not normal driving. It's lead foot driving. Turbocharged cars do not shoot up in boost without the throttle being opened wide to generate exhaust pressure enough to spool the Turbo.
 
I'm betting you need a driver mod. Always shooting up into boost is not normal driving. It's lead foot driving. Turbocharged cars do not shoot up in boost without the throttle being opened wide to generate exhaust pressure enough to spool the Turbo.
I'll make a video then something must be wrong, 20% throttle and it's right on the boost line or just under. If I keep it out of boost it takes like 5 seconds to get from 30 km/h to 40 km/h
 
I'll make a video then something must be wrong, 20% throttle and it's right on the boost line or just under. If I keep it out of boost it takes like 5 seconds to get from 30 km/h to 40 km/h
Even low throttle settings will generate "Boost". The point is, the throttle setting is what controls the boost level just as much as the waste gate setting does. You are just limiting the amount of boost the turbo will make with a boost controller or spring pressure on the waste gate. Turning down the available boost is like putting a governor on the throttle. For the most part, it isn't going to change your fuel mileage under "normal" driving conditions. My 1992 940 Turbo sedan gets an average of 24 mpg. I don't drive it slow. I just don't push it hard getting it up to speed all the time everywhere I go. You don't get power without fuel. It is a really simple concept.
 
Even low throttle settings will generate "Boost". The point is, the throttle setting is what controls the boost level just as much as the waste gate setting does. You are just limiting the amount of boost the turbo will make with a boost controller or spring pressure on the waste gate. Turning down the available boost is like putting a governor on the throttle. For the most part, it isn't going to change your fuel mileage under "normal" driving conditions. My 1992 940 Turbo sedan gets an average of 24 mpg. I don't drive it slow. I just don't push it hard getting it up to speed all the time everywhere I go. You don't get power without fuel. It is a really simple concept.
Okay.... So why am I getting 14MPG driving gently?
 
One thing I've noticed just driving it and looking at the vacuum/boost gauge is that to accerate even modestly I'm almost touching the middle of the gauge, I'm always shooting up into boost during a drive even though I'm driving normally.

Middle of the gauge, in the gauge that is in the late cluster, is at atmosphere, not boost
 
How did you test for vacuum leaks, have you tried a diffrent MAF.
With propane and also replacing all the hoses. And yes I tested the HVAC unit too, it holds vacuum in all settings.

I have not tried a different MAF because all the assholes around me that also own volvos hoard all their parts like they're sitting on gold. I couldn't even borrow one.
 
A tiny bit more throttle and I'm generating boost
That makes sense. That is what you should see. The throttle setting you are at is producing zero vacuum. You slightly increase the throttle and now the turbo is moving more air than the engine was using at partial throttle, thus, a positive pressure. The turbo was always spinning during light throttle. You just increased the exhaust pressure enough it stated to produce a positive pressure in the intake manifold.
 
That makes sense. That is what you should see. The throttle setting you are at is producing zero vacuum. You slightly increase the throttle and now the turbo is moving more air than the engine was using at partial throttle, thus, a positive pressure. The turbo was always spinning during light throttle. You just increased the exhaust pressure enough it stated to produce a positive pressure in the intake manifold.
Yeah that makes sense, it just doesn't make sense at the power level I am feeling
 
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