JZA80 Parallel Turbo mod

[1jz68u]

Hi guys i have performed this mod using the instructions on MKIV.com and just wondering if anyone else has done it and what the results have been like?

mine seems to still spool up the first turbo then it stops and then the both start, i can hear the first one spool at low RPM then no actual boost till 3500-4000k.

thinking i might change it back, although i do like how angry it sounds all the time rather that just after 4k.

thanks

[Draven]

true twin is slower than sequential... it's not much of a mod really

just swap back to how toyota made it

[PlacentaJuan]

the first turbo shouldnt spool up.

if you have a boost guage you will get nothing until >3000rpm then all of it at once (if your foot is down)

if you have done the 'mod' with the one way valves then after you have installed the valves you need to use full throttle to open both the actuators before you do anything else.

the sequential valves will open in order and iff you take your foot off the throttle before the sequence has finished the engine wont boost properly and you can not fix it unless you remove the pressure from each actuator line and run it again.

try taking the car to a quiet road with a minimum 80kph speed limit then installing the valves and straight away runnign it at full throttle until both turbos are online. if you cant do this then you have to drive really slowly to your 'run up strip' and make sure the car doesnt go near the turb ochangeover point (3800rpm)

[Draven]

if you get boost beforehand, you've done the mod wrong

[1jz68u]

there is no boost according to the gauge, but i can hear the turbo making a spooling sound or at least thats what it sounds like.

[Draven]

there will still be gas going through the turbo....

was everything fine before TTC? if not, I'd check for turbos spitting bits into intercoolre/.exhaust (exhaust more likely)

[PlacentaJuan]

i think if the guage is properly connected it is a better indication than sound.

try putting the car back to sequential and see if it runs normally.

also you never mentioned how you did the mod; removed or lockwired the actuators, installed one way valves, or did it electronically???

[1jz68u]

re routed the vacuum hoses using the instructions off mkiv.com

am going to try to change it back today

[PlacentaJuan]

re routing?? sounds a bit dodgy if u ask me

[1jz68u]

i did it just to see if i liked it.

PJ how do you find it? do you like it better or worse? do you know which makes more power?

[PlacentaJuan]

they make the same power.

i use ttc for highway driving because its better and more reliable for overtaking (sometimes the sequential system fucks up and you get no second turbo or no boost at all)

dont like ttc on the street coz its way too laggy but it impresses ppl when i let them drive my car lol

[1jz68u]

how hard was it to put the switch in? how long did it take?

[PlacentaJuan]

i dony use the switch because i dont understand how it works.

i use the one way valves and it takes about 30seconds to switch over

[Alchemist]

There is a guy on Supraforums(AceTT) who had TTC setup and he could switch between stock Twins and then TTC at the flick of a switch in the cabin. No idea how he set it up, but maybe worth searching there for some of his posts.

[BigWorm]

It'd be possible to swap the one way valves for solenoids (most of the factory ones I've seen/used have been one way), then wire up to switch and you'll be switching boosts and blasting Fezzas like Paul Walker himself.

~says to HSV driver~ "What's the retail on one of those things?"
"More than you can afford pal"
~says your pretend Vin Diesel sidekick~ "Smoke him!"

BTW, Glenn, my advice is get a single turbo setup for your 2J because the standard twins are junk whichever way you run them.