Josh K.
06-20-2007, 01:24 AM
I live on Maui and my options are very limited, My situation was as follows...
S13 Blacktop
FP Big28
555cc
Z32 Maf (blow through)
255lph pump
FMIC
Emance rom tune
I set off to increase my boost to 23psi.
it would reach 21psi but slowly fall off to 17psi. this was with my Profec II set at 100% with the HKS Actuator at 14psi (essentially no wastegate). It occurred to me that I'm an idiot and the stock BOV was leaking like niagra falls.
I then looked at my options and decided on the HKS BOV due to its pull type setup. after searching around I figured what the hell, I'll see if I can make any improvements to the stock one.
Here's what I did.
Take off the stock pressure side flange and you'll see a hole that goes up to the diaphram. tap that hole with a 10-32 tap and insert a set screw into the hole to block it off (there's a bleed hole in there that will be the new pressure source from other side of the plunger). Now just hook up the BOV backwards so that the original side that was out, is now air in (pressure side) and hook up the vacuum as original.
Its now a pull type BOV that will hold unlimited boost.
Only issue is piping if you want to run as recirc again, I run Blow through so I have no issues.
After doing this I left my original setting on the EBC and I hit 30psi in 3rd gear!!!! I thought 25 was max for the Big28? I then dropped the setting down and it is nuts at 20psi!
S13 Blacktop
FP Big28
555cc
Z32 Maf (blow through)
255lph pump
FMIC
Emance rom tune
I set off to increase my boost to 23psi.
it would reach 21psi but slowly fall off to 17psi. this was with my Profec II set at 100% with the HKS Actuator at 14psi (essentially no wastegate). It occurred to me that I'm an idiot and the stock BOV was leaking like niagra falls.
I then looked at my options and decided on the HKS BOV due to its pull type setup. after searching around I figured what the hell, I'll see if I can make any improvements to the stock one.
Here's what I did.
Take off the stock pressure side flange and you'll see a hole that goes up to the diaphram. tap that hole with a 10-32 tap and insert a set screw into the hole to block it off (there's a bleed hole in there that will be the new pressure source from other side of the plunger). Now just hook up the BOV backwards so that the original side that was out, is now air in (pressure side) and hook up the vacuum as original.
Its now a pull type BOV that will hold unlimited boost.
Only issue is piping if you want to run as recirc again, I run Blow through so I have no issues.
After doing this I left my original setting on the EBC and I hit 30psi in 3rd gear!!!! I thought 25 was max for the Big28? I then dropped the setting down and it is nuts at 20psi!