I agree...leave the wastegate alone and install a MBC (manual boost controller). Get a calibrated boost gauge. There are two things that need to be addressed to allow for the additional boost. The fuel cutoff is located over the drivers feet and is different for i/c and non i/c cars. The upgraded one cuts off fuel at a higher boost (13-15?. Can't remember). The interesting thing is how the dashboard "Turbo" light is controlled. There is actually a switch built into the boost gauge that will ground the light at either 10 or 15 psi, depending on i/c or not. There are actually 3 types of boost gauges. Non i/c short at 10 psi, i/c short at 15 psi and 84/85's don't have the switch (or lamp). Confused? I was. The neatest gauge to find has a wider yellow band to show the correct cutoff for an intercooled car. With the extra boost, consider the "Term 11" modification for more fuel. Check Turbobricks for more info. I use a SAAB cutoff switch since it has more flexibility and adjustability than the Volvo one.

Skip
'93 850GLT
'83 242TI Flathood

Install a boost controller, turn the boost up to 10psi, check for leaks and make sure everything works well, disable the turbo dash light, and enjoy the power increase.

The boost measurement hose should be connected to the "cool" side of the intercooler, before the intake manifold. Think of it this way:

#1 = pressure from cool side of intercooler
#2 = hose to boost controller
#3 = hose from boost controller to wastegate actuator

Usually manual boost controllers "trick" the wastegate into thinking the amount of boost it is recieving is lower than the actual amount, delaying the opening of the wastegate. You should start with the stock non intercooled boost pressure, and work your way up to 10-11psi and see how it responds to each increment.

An intercooler is the best modification that can be done to these cars, along with a slight boost increase. If I were you I would read up on intercooler installation and it's effect on power, as well as moderate boost increase.

My car came without an intercooler when I bought it (@ 182k). At 195k I added a new turbocharger (watercooled) as well as a manual boost controller and an intercooler kit. The power difference was very noticable, supposedly from the 125-130 range up toward 150-160 range.

Good luck and be careful not to overboost. Read turbobricks and you will get a better idea of what is going on.


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Zack Silver 83' 242Ti (222k)

Since you now have an intercooler, you can run MORE boost. You are not bad, you are not taking full advantage of the intercooler. I recall the non intercooled versions ran about 6psi of boost, and the intercooled ran about 10. So you should be able to move the wastegate setting up and pick up more power. I would check out the Turbobricks site and see what they say.

You might want to change out the boost gauge for the type with numbers, instead of the factory one.

Enjoy the power,

Mike in Tacoma
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Mike in Tacoma