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Discussion Starter #1
i was just curious if it would be possible to install tst(twin sequential turbos) into a 5 or 6m what makes the turbos spool at different times is it electrical sensors and such or what i was just curious if it is at all possible to get tst without going 2jz and would a 2jz manifold and turbos mount to a 5 or 6m just curious though curiousity did kill the cat
 

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The sequential setup is controlled by an exhaust bypass valve. It basically blocks off exhaust gases from the second turbo until a preset range. It then opens up and allows both turbos to run. It would not be cost effective to build such a kit for the 5/6M. Even a True Twin Turbo setup would be a waste. You can make the same amount of power out of a single turbo, and boost would only be slightly more lagged than smaller twin turbos. Turbo lag is way overrated anyways. According to Corky Bell's book, twin turbos for motors less than 180ci are useless; the 5M is 184ci IIRC. I would say this is borderline...and would still follow the same rule. With the right specs, a large single turbo will blow away a twin setup. Add to that, the 5/6M's have a very healthy torque band, so you won't even notice the lag much.

The 2JZ turbos and manifold wont mount to a 5/6M.

hope I killed ur cat...err...curiosity.
 

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Discussion Starter #3
thanx man that killed the cat alright i was just curious if it was possilble to have one small turbo and one huge turbo but i guess your right it isnt worth doing thanx for the input
 

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The 1JZ-GTE is significantly less than 180ci but its twin turbos work quite well! Turbo technology has changed a lot since Corky Bell wrote Maximum Boost.

I agree though, a twin sequential setup is beyond the capabilities of your average backyard tinkerer. The 2JZ setup definitely won't work in an M series engine either.
 

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Glad to see you here, Ray. :)

I could not agree with you more.
 

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Norbie said:
The 1JZ-GTE is significantly less than 180ci but its twin turbos work quite well! Turbo technology has changed a lot since Corky Bell wrote Maximum Boost.

I agree though, a twin sequential setup is beyond the capabilities of your average backyard tinkerer. The 2JZ setup definitely won't work in an M series engine either.
The 1JZ is not a sequential..it is a true twin turbo. I agree it does work pretty well in stock form, but raise the boost, and you will begin to see that the tiny turbos lose efficiency quickly. It's not a question of whether or not it works well, it's a matter of why would you do it for the high cost? For half the cost, you can make just as much power with a single turbo that has higher efficiency. Match the right turbine to the right compressor...and you can pretty much match the twin turbo's spooling. But like I said..lag is overrated. Actually, in some cases..spooling two turbos might take even longer den spoolling one large one. :) Sure a lot has changed since "Maximum Boost", but you can't change the physics of it all.

Danx for the welcome Quick...I'm glad to be here too! Keep on a look out for lots of nice products coming from my new company!
 

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I wasn't suggesting the 1JZ was sequential, I was simply making the case that twin turbos have their place on small-ish engines. It depends what you're trying to acheive really... if you want lots of boost and a big top end, a big single turbo is the go. If you want lots of torque for pushing a heavy car around (eg JZA70 Supra), a couple of small turbos can do the job better. Take a stock JZ engine for a drive if you get the chance, you might be surprised how well it works!
 

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Thanks Norbie et. al.,
Just what I wanted to hear!
1JZGTE half-cut arrives in country in two weeks now ...



- Justin
JZA61 in the works
 

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Ray is right regarding lag. It is overrated. If you are experiencing lag.. you're in the WRONG gear.

As far as twins vs. single. Single is the most cost effective. KIS principle especially on the 5M and not complex.

Even though I don't have substantial info to back it up... I am partial to the twin setup on the 2JZ vs. single. I believe the twins can make more HP than a large single. Take a look at the Jun Supra. I think most people choose single because it is easier to manage.
 

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re Lag: It all depends on your goals. Lag is an issue if you want to road race.

re Twins vs. Single: All of the cars that make big power are the singles. Check the dyno sheets at moreboost.org -- certainly theoretically the twin setups (even in parallel) should have _some_ advantage, but in practice it appears as if that is rarely the case in Supras.

I'm PM-ing you with a wheel question, James.
 

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Chris:

You are right about the road racing. Forgot about that for a moment. Brain-lag.
 

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Lag for road racing can be cured by correct turbo sizing. In either case, there's always a compromise. I doubt you will need the power of a large turbo on a road course..if you will be dropping down to such RPM levels that you will be out of the spool range. You'll get just as much lag on a twin setup capable of equal power levels.

Regarding the twin making more power. Turbo Mag did a test a little while back, they dynoed a HKS twin kit back to back with a Greddy T78 IIRC. Pound for pound...the single kit matched the power of the twin...and lag was so indifferent..it was negligible.
The JUN AKIRA Supra uses twin T88's to make 1400hp. There are a few large single Supra's out there making 1200-1400rwhp! Just remember...with the addition of another turbo, you have to deal with the extra heat it makes, both on the exhaust side..and the compressor side. To make the massive amounts of power to exceed a single turbo, you would need a very large, very effecient intercooler system. Basically, the point that a twin turbo setup would surpass a good single turbo in power making ability is high enough that the amount of HP would be ridiculous. Why waste so much time and money, when you could do the same with a single?
 

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Racetek82 said:
Lag for road racing can be cured by correct turbo sizing. In either case, there's always a compromise. I doubt you will need the power of a large turbo on a road course..if you will be dropping down to such RPM levels that you will be out of the spool range. You'll get just as much lag on a twin setup capable of equal power levels.
Yep. I would asser that you don't _want_ the power of a large single on a road course most of the time. In that case you will annihilate your tires unless you have traction control (like the RaceLogic).

Additionally, to be clear, you're talking about lag in terms of twin parallel setups. Twin sequential setups are much less laggy for the same power level. I know of no aftermarket twin sequential setups, however. ...horribly ineffective cost-wise for any aftermarket twin setup from everything I've seen.
 

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Just to add fuel to the fire, the JZA70 Supra when stock has less lag than the MA70 Supra, despite having a 500cc smaller engine - and both turbo setups have approximately equal max power potential. This demonstrates that a well setup non-sequential TT engine can work better than a single turbo engine. Whether this applies to big HP engines as well is another matter - as mentioned above, most people opt for single turbos when they want all-out power. I agree with Supra GTR's comments, most people go for singles because it's easier, not necessarily because it's better than twins.

Racetek: what makes you say twin turbos will generate more heat? If they're flowing the same amount of exhaust gas and compressing the same amount of inlet gas to the same pressure, I fail to see where the extra heat would come from...
 

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Norbie said:
Racetek: what makes you say twin turbos will generate more heat? If they're flowing the same amount of exhaust gas and compressing the same amount of inlet gas to the same pressure, I fail to see where the extra heat would come from...
Norbie... Actually, I think he's right on that. Turbo's that are used as part of a twin set-up are generally smaller than the singles that would be used in the same application... Smaller turbos spool quicker, but are less efficient at higher RPM's and higher boost levels than larger singles... which means high intake temps.

Personally, I wouldn;t say one setup is better than the other as a blanket statement... just depends on what ya wanna do with it. If ya need high hp numbers and don;t mind lag, then big singles are the way to go... for more responsive motor and boost sooner, then a twin is more suited...
 

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Supra Bob said:
If ya need high hp numbers and don;t mind lag, then big singles are the way to go... for more responsive motor and boost sooner, then a twin is more suited...
So... even if you want good spool with good power a single is going to be more cost-effective based on everything that I've seen.

It's all about pragmatism vs. idealism. Frankly I'm unconcerned about the idealistic argument that Norbie continually espouses because it's just not realistic (in terms of cost, ease of install, reliability, etc) for the aftermarket.

P.S. Norbie and I have argued this stuff to death at least three times now. :)
 

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Supra Bob said:
Personally, I wouldn;t say one setup is better than the other as a blanket statement... just depends on what ya wanna do with it. If ya need high hp numbers and don;t mind lag, then big singles are the way to go... for more responsive motor and boost sooner, then a twin is more suited...
Isn't that precisely what I said above?

Quick: my views aren't based on idealism, they're based on experience, ie I have driven both setups. Surely that has to count for something?
 

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Norbie said:
Quick: my views aren't based on idealism, they're based on experience, ie I have driven both setups. Surely that has to count for something?
Heck yeah -- experience counts for a lot.

So you're telling me that you've driven two cars with aftermarket turbo setups? One with parallel twins and the other with a single turbo?
-Chris
 

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Norbie said:
Supra Bob said:
Personally, I wouldn;t say one setup is better than the other as a blanket statement... just depends on what ya wanna do with it. If ya need high hp numbers and don;t mind lag, then big singles are the way to go... for more responsive motor and boost sooner, then a twin is more suited...
Isn't that precisely what I said above?

Quick: my views aren't based on idealism, they're based on experience, ie I have driven both setups. Surely that has to count for something?
Goddamn man, has that 2jz inflated that ego of yours? Why must you be so dogmatic in your responses to everyone who states an opinion? :roll: Easy baby, easy. We are all on the same side here. :scatter:
 
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