Gabe,

Get with me off list and we can go through a couple of simple solutions to what you are trying to do. The first question I have though, is your car intercooled?

Roy

Hi Gabe,

I sure do appreciate all the Volvo 240 turbo knowledge that this site does have, but it seems that when it comes to upgrades or just modifications, some people generalize the mods too much, or leave out modifications that are better suited to a specific vehicle, like a Volvo. I, too own a 240 Turbo and as you probably know, its a vehicle that isn't too popular.

But, as being a vehicle that isn't popular doesn't mean that there are no products or information on upgrading these cars. I have recently purchased a performance based book dealing with turbochargers in general and learned much knowledge from it. Anyway, back to your questions, that easiest way to raise boost pressure is by adjusting your wastegate. Afterall, thats the entire purpose of it, to limit the amount of boost created. But there is one fallback, as you raise boost, the engine will have the tendency to detonate, or preignition. The way to prevent this is to richen the fuel mixture. More fuel = lower combustion chamber temperatures = less chance of detonation. One thing that is great about the K-Jetronic fuel injection is, even though being primitive, has a Air flow sensor. One way to enrichen the fuel mixture is to install a blow off valve, before the cold start injector. This will dispurse some of your boost, but the all the air required to make that boost has passed the air flow sensor, hence making the mixture richer. You must install the blow off valve before the cold start injector as a faulty, leaking injector could cause fuel to be dispursed in the engine compartment, a big No NO!!

You can probably find a blow off valve in a junkyard on most later model 700 turbos and even other car manufactuer's blow off valves can be adapted to work.

Hope this helps!

If your car is like mine, there is a boost delay valve mounted to the passenger-side inner fender. It's behind the coolant overflow tank.

Bypassing this valve by connecting the three vacuum hoses together via tee fitting ( one hose to wastegate, one to pressure side duct, other to suction side duct)SHOULD lower the boost threshold by at least 200-300 rpm.

Please note: THIS WILL NOT INFLUENCE MAX BOOST, only lowers the point at which boost begins to be delivered.

I tend to shortshift and run under 4,500 rpm most of the time, and I find that this simple, costfree, reversible, harmless little mod gives me an enjoyable increase in performance in the low rpm range that I'm using.

Third gear is particularly strong.

It goes without saying that any vacuum leaks or pressure leaks will detract from the effect of this mod. Hoses must be in good shape, clamped joints in ducts sealed properly.

I'd like to give proper credit for this tip, but I can't remember where on the net I saw it...

Have fun.

K-jet cars can't be chipped like newer cars because it's a mechanical injection system. You might want to look into adding a manual boost controller similar to what is offered at http://www.dawesdevices.com/. You should also have a calibrated gauge installed before increasing the boost, if you don't already have one.

This would require the turbo actuator being adjusted and/or the ECU mapping being fine tuned. I should think it could be done but its a job for a pro with a rolling road/dynamometer. Many an engine has been killed by d.i.y. turbo adjustments. Alternatively, you might find an off the shelf chip for your ecu which would alter your engines boost/power characteristics for a small (10%ish) increase in power with better driveability. There is a company in the UK called Superchips (they have an internet site) which could probably help. Good luck.