i am wanting to know . how many psi can a 760 turbo motor handle? also how can i turn up my turbo.i would like to make some more psi with the factory turbo. will i need a boost controler or can i simply readjust the wasted gate diafram? alsohow can i enrich thefule to sustain morea stable increase in pressure? oh yes last but not least. i happen to have a t-4 in my grage can iput that on there? if an when my factory turbo dies?

well any info would be great. i have had a hard time looking up infofor just the 760 its also an 87 if that helps an im sure it dose.

 

- MBC (Manual Boost Controller), this is a way you can raise your boost (PSI). Do not mess with the wastegate.

- I wouldn't run more then 10-12 PSI on your stock turbo. Make sure you have an accurate boost gauge that can read at least 25 In Hg and 25 PSI.

 

well i orderd my mbc . so that will be nice to have. on another note do volvos have a unit like saabs apc box? if so that would be nice to know. most times they can be adjusted for a little more preformance. an one more question. what amount of psi can my 2.3l hold up to. i wish to know so i dont wear the motor out to fast or have internal parts fail.

oh yes i am going to the exaust shop this weekend. having a new down pipe made an just side discharging my exuast. that will help with flow.

 

What is an APC box?

Like I said you shouldn't run more then 10-12 PSI max. Hopefully you have a boost guage such as an Autometer that can read at least 25 In Hg / 25 PSI so that you know exactly how much boost your making and not guessing with the stock gauge if your car even has a stock gauge.

That is great to hear about the exhaust system, you will be happy.

 

my car has the stock guage but it dosnt read out in psi or bar. so its not realy helpful at all is it lol. but im am suprized. this turbo motor is only able to handel 10-12 psi. thats rather low.

oh yes saab apc Automatic Preformance Control Moudual. it is a small computer attached to the saabs ecu from factory. it monitors the turbo boost level , and the rate of increase over your rpm range. so if you give it a set level it will do its best to try an maintain that setting.

 

Get a real boost gauge, first things first.

Secondly no Volvo's don't have that APC thingy.

Also we aren't running huge turbos that can handle a lot of boost. Also 10-12 PSI is a big improvement over your more then likely 5-7 PSI you make now. Trust me I was at 5 PSI stock and can run anywhere from 10-15 PSI on my turbo because that is the max it can run effectively and effieciently. 15 PSI is a huge difference over 5 PSI.

You can run more boost but your turbo wont be able to handle it effiecently and also you will wear the engine down quicker and risk breaking things.

 

What year is your 760? If it was 1983-1984 it should have the forged pistons and crank which is a good thing and your engine might be able to take a little more PSI.

However your turbo might not be able to effeciently produce it and keep it constant.

It seems like your car has a Garrett T3 turbocharger.

 

http://cgi.ebay.com/ebaymotors/BOOST...spagenameZWDVW

I bought one of these and love it.
Really easy to read at all times day or night.

 

Yes that will work.

 

So you dont need reprogrammed ECU, you can use manual or electronic boost controller? to control pounds of boost?

 

Correct

However 1999+ Volvo models don't like MBC's or EBC's. If your 1998 and before your fine.

 

Oh I didnt know that 1999+ had problems.

But with manual boost controller you cannot make more boost on stock system, only lower it.

 

No you can raise boost with a MBC and lower boost too.

 

Interesting, can you explain how?

 

Can you use the internet LOL. I mean come on use GOOGLE, Wikipedia, Answers.com

"Manual boost control

A manual boost controller is a simple mechanical and pneumatic control to allow some pressure from the wastegate actuator to escape or bleed out to the atmosphere or back into the intake system. This can be as simple as a T-fitting on the boost control line near the actuator with a small bleeder screw. The screw can be turned out to varying degrees to allow air to bleed out of the system, relieving pressure on the wastegate actuator, thus increasing boost levels. These devices are popular due to their negligible cost compared to other devices that may offer the same power increase. Generally a manual boost controller will not be accessible from inside the car, though some are designed to be. An installation that allows access from inside the car (as opposed from inside the engine compartment) is more complex, as the tubing must be longer and a hole must be drilled. It is possible and beneficial to use two manual boost controllers at different settings with a solenoid to switch between them for two different boost pressure settings. Some factory turbocharged cars have a switch to regulate boost pressure, such as a setting designed for fuel economy and a setting for performance. Manual boost controllers do not solve partial throttle/full boost, drivability, and response or lag issues. They can be used in conjunction with some electronic systems."

"Electronic boost control [/align] A 3-port pneumatic solenoid. This solenoid allows interrupt or blocking of the boost pressure rather than just bleed type control.[/align] [/align] [/align] Electronic boost control adds an air control solenoid and/or a stepper motor controlled by an electronic control unit. The same general principle of a manual controller is present, which is to control the air pressure presented to the wastegate actuator. Further control and intelligent algorithms can be introduced, refining and increasing control over actual boost pressure delivered to the engine. At the component level, boost pressure can either be bled out of the control lines or blocked outright. Either can achieve the goal of reducing pressure pushing against the wastegate. In a bleed-type system air is allowed to pass out of the control lines, reducing the load on the wastegate actuator. On a blocking configuration, air traveling from the charge air supply to the wastegate actuator is blocked while simultaneously bleeding any pressure that has previously built up at the wastegate actuator. [edit] Control details [/align] A 4-port pneumatic solenoid installed to control a dual port wastegate controlled by a single PWM PID controller[/align] [/align] [/align] Control for the solenoids and stepper motors can be either closed loop or open loop. Closed loop systems rely on feedback from a manifold pressure sensor to meet a predetermined boost pressure. Open loop systems have a predetermined control output where control output is merely based on other inputs such as throttle angle and/or engine RPM. Open loop specifically leaves out a desired boost level, while closed loop attempts to target a specific level of boost pressure. Since open loop systems do not modify control levels based on MAP sensor, differing boost pressure levels may be reached based on outside variables such as weather conditions or engine coolant temperature. For this reason, systems that do not feature closed loop operation are not as widespread. Solenoids are driven by pulse-width modulation as they are binary state devices, either allowing air flow or blocking it between any two given ports. By modifying the pulse width at a sufficiently high frequency, average air pressure over time can be controlled. Solenoids may require small diameter restrictors be installed in the air control lines to limit airflow and even out the on/off nature of their operation. Stepper motors allow fine control of airflow based on position and speed of the motor, but may have low total airflow capability. Some systems use a solenoid in conjunction with a stepper motor, with the stepper motor allowing fine control and the solenoid coarse control. Many configurations are possible with 2-, 3-, and 4-port solenoids and stepper motors in series or parallel. Two port solenoid bleed systems with a PID controller tend to be common on factory turbocharged cars. [edit] Advantages Since less positive pressure can be present at the wastegate actuator as desired boost is approached the wastegate remains closer to a completely closed state. This keeps exhaust gas routed through the turbine and increases energy transferred to the wheels of the turbocharger. Once desired boost is reached, closed loop based systems react by allowing more air pressure to reach the wastegate actuator to stop the further increase in air pressure so desired boost levels are maintained. This reduces turbocharger lag and lowers boost threshold. Boost pressure builds faster when the throttle is depressed quickly and allows boost pressure to build at lower engine RPM than without such a system. This also allows the use of a much softer spring in the actuator. For instance, a 7 psi spring together with a boost controller may still be able to achieve a maximum boost level of well over 15 psi. The electronic control unit can be programmed to control 7 psi at half throttle, 12 psi at 3/4 throttle, and 15 psi at full throttle, or whatever levels the programmer or designer of the control unit intends. This partial throttle control greatly increases driver control over the engine and vehicle. [edit] Limitations and Disadvantages [

 

I have a MBC on the wifes white 850 running 12PSI.

 

ok no bull**** ive run 28 psi on a stock volvo turbo engine ...with the help of some 110 octane.
1. you cant run more than 14 psi with the factory boost guage connected..it has an aut cut out
2. you can disconnect this
3. you dont need a mbc to control boost if you have an adjustable wastegate..this is very easy to adjust>>>>caution>>>> you only want to increase boost a couple pounds at a time i think two turns is about a pound or two of boost..this is a free upgrade and is safer than using a mbc
4.volvos do not use an apc like saab altho you can adapt it to work ive tried this and its not worth the effort
5.if you have a manual transmission you have a garret t-3 but either turbo can be pushed well beyond 12 psi
6. at 16 psi and up the clutch will start to slip..i installed a new unit but still doesnt handle the torque past 16 psi
in all reality you only need an open air filter and to adjust your wastegate on your turbo
7. i have an msd coil , open airfilter and a blowoff valve and ive seen consistant 16-20 psi NOTE :you have to disconnect your factory boost guage to achive more than 14 psi
8. 14 psi is not straining the engine ..also a blow off valve is recommended but factory stff will do.
9. if you have the smaller mistubishi unit i suggest not runing more than 17 psi
10. garrets are efficent to a little over 20 psi but again ive seen 28 on mine
11. once again this is from a 300 $ volvo.
12.at 15 psi in a stick car shifting to 2nd early in boost will result in tire spin to 60 mph and a 3 foot scratch in third,
this is with an electronic overdrive unit

 

oh ya if you want more than 15 psi its a good idea to get some octane booster or just 100 + to keep knock down
if you want to avoid this set your boost at 13.7 or 14 psi and you should just be under the limiter wich is ran from the factory boost guage...just unhook it at get an after market unit and problem solved

 

Well I seriously cannot believe you ran 28PSI on a stock turbo Volvo. You might have ran it for all of about 5 seconds and then your engine blew up. I could believe that. Or you had it turned up to 28PSI but never went near that amount.

 

haha awesome 28 pounds, i bet it ripped if that clutch grabbed. thats like a built honda, little 4 bangers make like 30 pounds and run 10 seconds. full built motors