INDYPWR Posted March 3, 2006 Share Posted March 3, 2006 do any of you guys achieve 1bar or even 1.2bar with decatts but no restrictor ring? is that possible? the reason i asked is that i have both decatts and running 2.5" pipping all the way back but with no restrictor ring (still waiting for it from Chris). i think i am boosting .09 most of the time with both decatts. for your information, i have a soarer with jspec on it and with dual exhaust, not single like you guys. tks for your help. Quote Link to comment Share on other sites More sharing options...
heckler Posted March 3, 2006 Share Posted March 3, 2006 when i decatted my J-Spec with out a restrictor ring - i got waaaay over 1.2 bar Quote Link to comment Share on other sites More sharing options...
SEDGE Posted March 3, 2006 Share Posted March 3, 2006 same as Quote Link to comment Share on other sites More sharing options...
Guest chiefvinso Posted March 3, 2006 Share Posted March 3, 2006 I'm getting .95 bar with the second cat removed. Are your tubbies ok and isnt the soarer a 2.5? What was it boosting at with cats in? Quote Link to comment Share on other sites More sharing options...
INDYPWR Posted March 3, 2006 Author Share Posted March 3, 2006 tks for your replies guys. heckler: how did you achieve over 1.2bar with both decatts and no restrictor ring? are you running colder plugs and fmic? i am running fmic and colder plugs but no fcd. chiefvinso: my tubbies are ok, 2nd turbo kicks in normally as it should. i have the soarer chassis but with "aristo" engine and yes it's 2.5. i believe it's the same engine as you guys on jspec supra. maybe i should put 1 cat back and see what happens. Quote Link to comment Share on other sites More sharing options...
Scoboblio Posted March 3, 2006 Share Posted March 3, 2006 A jspec supra will boost way over 1.2 bar with no cats and no restrictor ring because the wastgate isn't big enough to control the boost to a resonable level. You don't need any supporting mods to reach this boost level because without restrictions the jspec system will boost itself to destruction - this is why we put in a restrictor ring, then colder plugs and quite often a new fuel pump to keep it at a safe(ish) 1.2bar. I think most of the UK spec guys see around 0.9 bar with no cats because of the larger wastgate that can control the boost better. If you do have the same engine as a J-spec supra I'd be careful about trying to solve this problem before you install a restrictor ring - you'll see waaaaaaay over the safe level of boost. Quote Link to comment Share on other sites More sharing options...
D8MOA Posted March 4, 2006 Share Posted March 4, 2006 tks for your replies guys. heckler: how did you achieve over 1.2bar with both decatts and no restrictor ring? are you running colder plugs and fmic? i am running fmic and colder plugs but no fcd. chiefvinso: my tubbies are ok, 2nd turbo kicks in normally as it should. i have the soarer chassis but with "aristo" engine and yes it's 2.5. i believe it's the same engine as you guys on jspec supra. maybe i should put 1 cat back and see what happens. aristo engines are 3.0 the same as a j spec supra which is also 3.0! your 2.5 twin turbo might have bigger waste gates and will prob req a boost controler rather then the restrictor ring! Quote Link to comment Share on other sites More sharing options...
INDYPWR Posted March 4, 2006 Author Share Posted March 4, 2006 aristo engines are 3.0 the same as a j spec supra which is also 3.0! your 2.5 twin turbo might have bigger waste gates and will prob req a boost controler rather then the restrictor ring! hehe.......i dont have 2.5 tt that is for sure. i have an aristo engine. Quote Link to comment Share on other sites More sharing options...
INDYPWR Posted March 4, 2006 Author Share Posted March 4, 2006 A jspec supra will boost way over 1.2 bar with no cats and no restrictor ring because the wastgate isn't big enough to control the boost to a resonable level. You don't need any supporting mods to reach this boost level because without restrictions the jspec system will boost itself to destruction - this is why we put in a restrictor ring, then colder plugs and quite often a new fuel pump to keep it at a safe(ish) 1.2bar. I think most of the UK spec guys see around 0.9 bar with no cats because of the larger wastgate that can control the boost better. If you do have the same engine as a J-spec supra I'd be careful about trying to solve this problem before you install a restrictor ring - you'll see waaaaaaay over the safe level of boost. it's just weird that i am not boosting 1.2 bar with both decatts and no restrictor ring. i am running fmic, colder plugs, and walbro pump. before however, i was using greddy boost controller and i was always hitting 1.2bar but then i was hitting fuel cut, even with 2nd turbo "not" kicking in. now, i took out boost controller and still running decatts and no ring, i am boosting about 14psi. so , is that ok ? Quote Link to comment Share on other sites More sharing options...
D8MOA Posted March 4, 2006 Share Posted March 4, 2006 chiefvinso: my tubbies are ok, 2nd turbo kicks in normally as it should. i have the soarer chassis but with "aristo" engine and yes it's 2.5. i believe it's the same engine as you guys on jspec supra. maybe i should put 1 cat back and see what happens. so you car is a 3.0l? twin turbo! not a 2.5? Quote Link to comment Share on other sites More sharing options...
MKIVDreamer Posted March 4, 2006 Share Posted March 4, 2006 do any of you guys achieve 1bar or even 1.2bar with decatts but no restrictor ring? is that possible? the reason i asked is that i have both decatts and running 2.5" pipping all the way back but with no restrictor ring (still waiting for it from Chris). i think i am boosting .09 most of the time with both decatts. for your information, i have a soarer with jspec on it and with dual exhaust, not single like you guys. tks for your help. You have a dual exhaust system on a 2JZ-GTE? Maybe this is causing back pressure which is restricting the boost creep? Quote Link to comment Share on other sites More sharing options...
Scoboblio Posted March 4, 2006 Share Posted March 4, 2006 If you were hitting a constant 1.2bar with an EBC then chances are there's something still restricting the exhaust, have you got the standard catback system on it? I'm not sure about the soarar but the standard Supra exhaust is quite restrictive. Perhaps this is holding it to 0.9bar, until the electronic controller tells it to go higher? Quote Link to comment Share on other sites More sharing options...
INDYPWR Posted March 4, 2006 Author Share Posted March 4, 2006 If you were hitting a constant 1.2bar with an EBC then chances are there's something still restricting the exhaust, have you got the standard catback system on it? I'm not sure about the soarar but the standard Supra exhaust is quite restrictive. Perhaps this is holding it to 0.9bar, until the electronic controller tells it to go higher? the problem i was facing when i had the EBC was that i was already hitting 1.2bar before 2nd turbo kicks in. i know for a fact it's true because 2nd turbo does not kick in until around 4000rpm. i was hitting 1.2 bar maybe with 1st turbo. i dont have standard cat back on anymore. no more catts either, all gone ! i am running 2.5" from downpipe all the way back to aftermarket mufflers. the soarer has standard dual exhaust, which was 2 1/4inch pipping...stock! i opted out to have 2.5" all the way after the aristo swap. i am also running a "free" flow cat...not even close to being "restrictive". do you think i should put one cat back to get back pressure? i dont know. for some reason i am not hitting 1bar nor 1.2bar with my set up right now. i guess it's different having aristo swap on my soarer. Quote Link to comment Share on other sites More sharing options...
INDYPWR Posted March 4, 2006 Author Share Posted March 4, 2006 You have a dual exhaust system on a 2JZ-GTE? Maybe this is causing back pressure which is restricting the boost creep? the soarer comes with standard dual exhaust. i changed the piping to 2.5"inch all the way back; no catts, no ring at all. Quote Link to comment Share on other sites More sharing options...
INDYPWR Posted March 4, 2006 Author Share Posted March 4, 2006 so you car is a 3.0l? twin turbo! not a 2.5? yes, it's a twin turbo 3.0 aristo being swap on my toyota soarer. Quote Link to comment Share on other sites More sharing options...
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