Hey gang, I did do a search but couldn't find anything; I'd like to know if there was a way to lower the boost on my 1JZ Soarer with the stock twins. I've got a HKS boost controller, but even with that off the turbos creep up to about 12psi. Does anyone know what they should be sitting at stock? I've got a 3" (Maybe more) Supra system with the cat still in place and a HKS shroom, which probably isn't helping the high boost at all. I know these turbos are sensitive, I'd like more control over what they boost to because of this. Could I pop a restrictor ring after the cat and make the boost controller work harder if I wanted more choo choo? Would boosting at say 12psi without a restrictor and 12psi with one make the same power? Potentially thick question that. Thanks in advance chaps.
Yea man the OEM Wastegates are too small to control the boost with a decat/ 3" system. You can buy a restrictor ring off eBay for a couple of quid and that means you can use the boost controller to raise the boost again.
12psi is perfectly safe on the stock twins dude. If it starts boosting over 14 that's when there would be long term issues
Restrictor ring will hold back power at the same boost. But if you want to lower it, that's your only real option as it stands.
Thanks for the replies chaps. I've got the exhaust off at the moment so I'll buy a ring and see how it affects it. Tarr.
Rings generally come, off the shelf, in 1bar and 1.2bar. Sure you could get the hole sized to suit, but if you're running a stable 12psi personally Id not worry about it.
