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Evolving Member
Joined: Jan 2010
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From: Seattle
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stock 04 evo 8
2 days ago I installed a JDM MR Diverter valve (aluminum) on my evo. I thought I tightened it up pretty good but maybe i didn't.
Earlier today I was driving my car and I did a run from 1st gear to 4th gear testing my boost level. 1st and 2nd gear hit target boost and I think 3rd gear did to but 4th gear did not. Max boost 4th gear hit was about 17ish.
However, about 5 minutes later I was cruising along in 4th gear at about 60mph and did another WOT pull. This time i hit target boost, about 19.5 lbs.
My question is this: Did i hit target boost when I did just a 4th gear roll because my rpms were lower when I started the pull and therefore it had more time to hit target boost? (I don't actually know if my rpms were lower but i think they may have been) And is the reason I did not hit target boost in 4th gear when i did the 1st through 4th pull because I was shifting out of 3rd at about 7000rpms (pretty sure it was 7000) and therefore my rpms were higher when shifting into 4th and my boost was already starting to taper before it hit max boost? Or is it probably just a leak?
Also, I have a Hallman boost controller (uninstalled) sitting in my room that I'll be installing soon. Theoretically after I install the boost controller it will hit target boost in either of the above situations because it won't taper correct?
Only mods are a boost gauge and the JDM MR DV.
I don't believe I had this problem before installing the DV but I maybe have not noticed it before.
Either way I'll be going under the hood tomorrow to make sure I tightened everything correctly but I thought I'd see if anyone else has had this issue before.
Thanks for any input
2 days ago I installed a JDM MR Diverter valve (aluminum) on my evo. I thought I tightened it up pretty good but maybe i didn't.
Earlier today I was driving my car and I did a run from 1st gear to 4th gear testing my boost level. 1st and 2nd gear hit target boost and I think 3rd gear did to but 4th gear did not. Max boost 4th gear hit was about 17ish.
However, about 5 minutes later I was cruising along in 4th gear at about 60mph and did another WOT pull. This time i hit target boost, about 19.5 lbs.
My question is this: Did i hit target boost when I did just a 4th gear roll because my rpms were lower when I started the pull and therefore it had more time to hit target boost? (I don't actually know if my rpms were lower but i think they may have been) And is the reason I did not hit target boost in 4th gear when i did the 1st through 4th pull because I was shifting out of 3rd at about 7000rpms (pretty sure it was 7000) and therefore my rpms were higher when shifting into 4th and my boost was already starting to taper before it hit max boost? Or is it probably just a leak?
Also, I have a Hallman boost controller (uninstalled) sitting in my room that I'll be installing soon. Theoretically after I install the boost controller it will hit target boost in either of the above situations because it won't taper correct?
Only mods are a boost gauge and the JDM MR DV.
I don't believe I had this problem before installing the DV but I maybe have not noticed it before.
Either way I'll be going under the hood tomorrow to make sure I tightened everything correctly but I thought I'd see if anyone else has had this issue before.
Thanks for any input