Thread: Best way to adjust boost pressure

Originally Posted by rar110

I have a Garrett GT28R turbo with a wastegate set by the installer at about 10 psi. I know others are running much higher boost at 15 to 25 psi boost.

What is the best way to adjust boost? I have read about manual & electronic boost controllers, and wastegates with a manual adjustment. Mine has no thread on the arm for adjustment. Also, if adjusting boost should I get a boost guage fitted?
Thanks.

G'day Pete, It is possible to get actuators for different boost but you can also cut your actuator rod and thread it (L and R) and put a long adjuster nut in line and adjust the rod shorter, I think Rijidid (Murray) may have a thread on this procedure somewhere here otherwise as you say boost controllers. My T3 was set at 10psi and has an adjustable actuator rod. Some time ago I adjusted the rod shorter and got the boost up to about 14-15psi, but I had to shorthen the rod adjustment about 10mm. It was very tight after I finished and I have decided to install a manual boost controller and put the actuator rod back to its original length,but haven't got around to doing it yet. A job for 'ron'. It would be advisable to install a boost gauge to keep an eye on the pressure also a blow off valve. How is the box going.

skip the blow off valve (thats a riceboy petrol thing you dont need it on a diesel) and shorten the adjusting rod after you have a boost gauge that can handle 30+psi of boost wind er up then up the fuel after you get an EGT gauge.

Originally Posted by rar110

I have a Garrett GT28R turbo with a wastegate set by the installer at about 10 psi. I know others are running much higher boost at 15 to 25 psi boost.

What is the best way to adjust boost? I have read about manual & electronic boost controllers, and wastegates with a manual adjustment. Mine has no thread on the arm for adjustment. Also, if adjusting boost should I get a boost guage fitted?
Thanks.

By far the easiest route with a 4BD1 (IE with original NA pump) is to set your boost pressure using fuelling. A boost gauge in this instance is mandatory though

Just remove the wastegate pressure line altogether and plug it up. I have a non adjustable wastegate which initially had the pressure set at 7.5psi I have adjusted the fuel screw to achieve 15psi at the inlet manifold downstream of the intercooler, and can not get my EGT's above 575degrees(Upstream). After 100K all is well

(BTW, shortening a wastegate control rod increases boost, lengthening lessens)

Now go and find some hills

JC

Originally Posted by Bearman

......... I think Rijidid (Murray) may have a thread on this procedure somewhere here..........

Yep, here's that thread. It's not too hard to do.

Cheers, Murray

Reclaiming factory boost level

Cut and thread the wastegate arm.
Just unhooking the line may mean the wastegate still opens due to exhaust pressure on the flap. But shortening the arm gives more spring force holding it closed.

Originally Posted by Dougal

Cut and thread the wastegate arm.
Just unhooking the line may mean the wastegate still opens due to exhaust pressure on the flap. But shortening the arm gives more spring force holding it closed.

I agree but at 15psi, not an issue. Maybe you '30psi boys' may see that happen though...

JC

Turbotech manual turbo boost controller- THE ORIGINAL! - eBay Turbo Parts, Performance Parts, Car Parts, Accessories, Cars, Bikes, Boats. (end time 03-Jul-10 06:05:07 AEST)

Ones like this work well

Originally Posted by rijidij

Yep, here's that thread. It's not too hard to do.

Cheers, Murray

Reclaiming factory boost level

Great thread Murray. I bought the same EGT guage.