wastegate actuator mod
08-21-2004, 12:57 AM
#1
0.5 BAR
Thread Starter
Join Date: Jun 2004
Posts: 140
wastegate actuator mod
some of you may recall that i was having problems getting my boost pressure down to soemthing reasonable.
i tried various things, including buying a whole new one from egay... and that turned out to be an identical peice to what i already had. desperate, i decided to borrow an adjustable one from a friend and tried using it. (an interesting feature of it was that the can actually bolts to the mounting bracket- its not permanately attached)
finally, fed-up with having either a slow to spool turbo or a detonating monster, i decided it was time to do some surgery.
first, i cut open the wastegate actuator radially around the crimp that holds the top and bottom peices together. with this completed, i was able to remove the spring from the housing and unbolt the can from the mounting bracket
i took the spring into work with me one day, where we have a digital scale. using the old formula F=kx, i compressed to the spring 1/2 inch and read what the scale said. it was 25lbs, so my spring was a 50lb/in spring. armed with this knowledge, i cruised on over to mcmaster-carr and found a spring that was just under 25lb/in... pretty much exactly what i was looking for. $9 later, and i had 5 of them delivered to my door.
so now i had a spring and a completely disassembled wastegate actuator. because the only part of the actuator that needs to be sealed is the top half, i just used some high temp rtv to seal the diaphram to the housing.
now i needed some way of clamping the two halves back together, so that the spring would compress. i traced the holes from the bottom half of the can into a 1/8 in think peice of Al and drilled some holes. i then cut another peice just like it and drilled holes on the outer edge, so that i had two holes through which i could clamp the two halves of the can back together with bolts.
the results are absolutely awesome. in 3rd gear and up, i can built 3-4lbs of boost BEFORE 2000rpm. my target of 6-7psi is reached by about 2500, and it goes up to about 9psi towards 5-6k.
i tried various things, including buying a whole new one from egay... and that turned out to be an identical peice to what i already had. desperate, i decided to borrow an adjustable one from a friend and tried using it. (an interesting feature of it was that the can actually bolts to the mounting bracket- its not permanately attached)
finally, fed-up with having either a slow to spool turbo or a detonating monster, i decided it was time to do some surgery.
first, i cut open the wastegate actuator radially around the crimp that holds the top and bottom peices together. with this completed, i was able to remove the spring from the housing and unbolt the can from the mounting bracket
i took the spring into work with me one day, where we have a digital scale. using the old formula F=kx, i compressed to the spring 1/2 inch and read what the scale said. it was 25lbs, so my spring was a 50lb/in spring. armed with this knowledge, i cruised on over to mcmaster-carr and found a spring that was just under 25lb/in... pretty much exactly what i was looking for. $9 later, and i had 5 of them delivered to my door.
so now i had a spring and a completely disassembled wastegate actuator. because the only part of the actuator that needs to be sealed is the top half, i just used some high temp rtv to seal the diaphram to the housing.
now i needed some way of clamping the two halves back together, so that the spring would compress. i traced the holes from the bottom half of the can into a 1/8 in think peice of Al and drilled some holes. i then cut another peice just like it and drilled holes on the outer edge, so that i had two holes through which i could clamp the two halves of the can back together with bolts.
the results are absolutely awesome. in 3rd gear and up, i can built 3-4lbs of boost BEFORE 2000rpm. my target of 6-7psi is reached by about 2500, and it goes up to about 9psi towards 5-6k.
08-21-2004, 01:42 AM
#2
3.0 BAR
Join Date: Apr 2003
Posts: 2,612
Re:wastegate actuator mod
what size of turbo are you running? good job on the wastegate modification. where do you have the wastegate actuator connected to for the boost source so the wastegate opens? i ask cause i had the w/g connected to the turbo compressor housing and then i Td' it off the BOV and it spools up way faster.
08-23-2004, 07:13 PM
#3
3.0 BAR
Join Date: Mar 2003
Posts: 21,479
Re:wastegate actuator mod
Damn, very good use of your resources. 
My lazy *** would have gave up and bought a lower actuator. :P
__________________
Best Car Insurance | Auto Protection Today | FREE Trade-In Quote
My lazy *** would have gave up and bought a lower actuator. :P__________________
Best Car Insurance | Auto Protection Today | FREE Trade-In Quote
08-24-2004, 01:34 AM
#5
0.5 BAR
Thread Starter
Join Date: Jun 2004
Posts: 140
Re:wastegate actuator mod
Originally Posted by Dr.Boost
Damn, very good use of your resources. My lazy *** would have gave up and bought a lower actuator. :P
My lazy *** would have gave up and bought a lower actuator. :P
08-25-2004, 10:10 PM
#6
1.0 BAR
Join Date: Dec 2002
Posts: 494
Re:wastegate actuator mod
ive tried the same thing in the past only i didn't quite have all the resources you had, i basically bent the lip of the cansister with a flat nose screwdriver (took forever) and popped the top off, remove the spring, cut a few links off it, put it back in, sealed it with some rubber gasket ---- and tried to bend the lip of the canister back into place, ended up with an ugly hacked up wastegate that leaked too bad to work even the slightest, ended up tossing it out.
Thread
Thread Starter
Forum
Replies
Last Post
