Removing the sequential turbo system on a 2jz

[ryanfels]

Ok. So i just got a txt from my mate saying he just took my jzx61 for a drive after wiring it and he said the gap between the turbos kicking in was quite big.

So ive been thinking, is it possible to remove the sequential system so that the turbos come on together?

I did a quick search and i found this http://www.toymods.net/forums/showth...uential+turbos and i read on the old forums that you can pretty much remove most all that to get the turbos coming on together.

Is this true?

Ryan

[Norbie]

Disabling the sequential system does not require any mechanical modifications beyond the re-routing of a couple of vac hoses. There is also a switchable electronic method. This is well documented on supraforums and many other sites.

There are additional benefits in removing certain parts of the sequential system but this is far from a trivial task, and at this point you're better off looking at a budget single turbo setup. Note that the stock twins are very laggy with the sequential system disabled.

[ryanfels]

Oh ok. Im not really after any extra power, i just want a smooth engine so i really want to avoid the single turbo.

Hes saying it feels like theres a small drop in power between the turbos and it gets a big kick when the 2nd kicks in. I thought the point of the twins is for there not to be a big kick between them.

Ill have a look on the supraforums now

[The Last Streetfighter]

I think there is a good write up on jzx147.com too.

[Z2TT]

Is there any advantage of removing the sequential setup?

[wilbo666]

Electronic method

http://www.toymods.net/forums/showthread.php?t=39941

Cheers
Wilbo

[woggin]

as norbie said, its quite laggy in TRUE TWIN mode, with the power not coming in till around 3.2k then you get planted in your seat, full boost doesnt come till around 4k...

is the motor running more boost??

14psi on the first turbo gives the best changeover to the 2nd turbo coming online, there is only a small dip, where if you run std 10psi, the dip is quite big.

I find it easier to hop out and change over the 2 vac lines to get TTC mode, its simple and only takes 20secs or so!! cant be bothered with wiring into the harness at this point!

[02JZE]

Just go single. can do it cheaply if your not crazy on power upgrades and it looks alot cleaner.

[ryanfels]

We havent changed anything so i would assume its runnings standard boost.

I would go single but time isnt on my side, this car is got to tow my mates boat at christmas.

Hmmm i cant seem to sign up to the supra forums

[1jz68u]

keep sequential, i had TTC for about a month and hated it. too much lag.

is it auto or manual? this might make a difference if its auto i guess

[Norbie]

Hes saying it feels like theres a small drop in power between the turbos and it gets a big kick when the 2nd kicks in.

This is normal, every 2JZ-powered car I've been in does this. It would probably perfectly smooth if the car is 100% stock (including the exhaust system) but I'd be surprised if any of them exist anywhere in the country.

[PlacentaJuan]

i use the vacuum hose method, as wog said it only takes a few seconds.

i switch to ttc every now and then for a bit of fun but i definately prefer the low down power of sequential

[Draven]

I can't find my old dyno chart at the moment, but you can see in the power delivery where the changeover is happening. It's not a drop in power as such, just the curve flattens out a lot, so the increase in power is less.

I tried true twin mode for a while, and it was almost as laggy as my gt35 is.

I'd suggest living with that quirk of the sequential system (and loving the mass of down low torque), since it sounds like you don't want the big kick in the pants of true twin or a big single

[ryanfels]

Ok thanks guys!

yea its manual. The test drive was done with no exhaust, just the dump pipe so ill leave it till i have my exhaust on and then decide but it looks like ill just leave it anyway.

[Draven]

be a bit careful running the 2j with no exhaust - you'll get big boost spikes (because the teeny little wastegate has issues with massive non-restrictive exhausts), which is probably contributing to the weird feeling. Wait till it's got a proper exhaust on it and see what it feels like.