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not a bad idea but I wanna see what the 2jz can do.
Understandable. I bought an LS3 for my IS, but then decided the car wasn't nice enough to warrant the effort and expense, so I shopped for a nicer one for the swap.

After 6-8 months of shopping, I ended up finding a nice clean already-turboed one for fair money. Needed some work but had good bones... Originally the scheme was to get the 2J/r154 powertrain all squared away and sell as a complete engine/trans/ecu package, but instead decided to keep the 2J and play with it for a while.

Every time I floor it and wait for something to happen, I think about that LS3 still sitting on the floor of my garage.

An LS3 shaves over 200lb off a turbo 2J, and that's up front where it counts most. A stock LS3 is good for ~395whp, but we all know that can be improved to 425 or so with nothing more than a fairly mild cam. So the peak power of the LS and 2J would be about the same but the LS3 would obviously have a shit load more bottom end torque and response.
 

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Understandable. I bought an LS3 for my IS, but then decided the car wasn't nice enough to warrant the effort and expense, so I shopped for a nicer one for the swap.

After 6-8 months of shopping, I ended up finding a nice clean already-turboed one for fair money. Needed some work but had good bones... Originally the scheme was to get the 2J/r154 powertrain all squared away and sell as a complete engine/trans/ecu package, but instead decided to keep the 2J and play with it for a while.

Every time I floor it and wait for something to happen, I think about that LS3 still sitting on the floor of my garage.

An LS3 shaves over 200lb off a turbo 2J, and that's up front where it counts most. A stock LS3 is good for ~395whp, but we all know that can be improved to 425 or so with nothing more than a fairly mild cam. So the peak power of the LS and 2J would be about the same but the LS3 would obviously have a shit load more bottom end torque and response.
Yeah Like I said I'm content with what I got. Like I said bit zipper and extra pull on the highway is really all I want. But probably since its a V8. Wonder what you'd get turboing an LS then.
 

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Wonder what you'd get turboing an LS then.
Displacement and excellent cylinder heads are your friends. A very mild turbo LS will easily put down 600whp... Even a stock cam 4.8L. A friend set up a GTO with a 4.8 and Precision ~66mm that made 650whp @ 15 or 16psi.

Richard Holdener on YouTube has a million engine dyno tests of various turbo (and NA) LS stuff. Check it out if you want to be tempted!
 

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Displacement and excellent cylinder heads are your friends. A very mild turbo LS will easily put down 600whp... Even a stock cam 4.8L. A friend set up a GTO with a 4.8 and Precision ~66mm that made 650whp @ 15 or 16psi.

Richard Holdener on YouTube has a million engine dyno tests of various turbo (and NA) LS stuff. Check it out if you want to be tempted!
Y'all ever tried 600whp on twin turbo with the 2jz? I don't hear too many people talking about that for real my guess is it would be a pain to set up but I'm curious.
 

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Displacement and excellent cylinder heads are your friends. A very mild turbo LS will easily put down 600whp... Even a stock cam 4.8L. A friend set up a GTO with a 4.8 and Precision ~66mm that made 650whp @ 15 or 16psi.

Richard Holdener on YouTube has a million engine dyno tests of various turbo (and NA) LS stuff. Check it out if you want to be tempted!
Or twin turbo in an IS at least for the same power.
 

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Bigger twins in the IS would probably be difficult to package.
It might be I've seen some people do it though. The smallest turbo from precision from what I saw gets bout 385hp. Idk how twin turbos work. But I'm guessing if you get two of them you'll have max performance of 770 which is good enough for me.
 

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It might be I've seen some people do it though. The smallest turbo from precision from what I saw gets bout 385hp. Idk how twin turbos work. But I'm guessing if you get two of them you'll have max performance of 770 which is good enough for me.
Twins are setup in compound. One pressurizes the next. It is way more efficient and less expensive. To do a single. You will waist more time and money with twins. That is why everyone switches to single. That and space along with less leak possibilities.
 

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Most people switch to a big single because you can spool the big single to full boost faster at 700whp than you can with twins (unless it's sequential - but that take a lot of time and money to get the tuning right). I know only of 1 person right now that prefer sequential and he makes 700+whp on his supra (look up Stu Hagen). Even on stock twins that are in TTC mode, you don't get full boost until almost 5k rpm (don't start building until 3.5k to 4k rpm - ask me how I know) and you top out at 6.5k rpm maybe 7k . The powerband is not that great to support twins, whereas a single with the right tuning, you can get spooling as low as 2.5k rpm and full boost 3.5k to 4k all the way to 7k at 700whp. Plus, it's a ton cheaper single tuning is a lot easier. Also, to diagnosis sequential when it goes out is a pain in the ass so that's also why most people switch. Lastly, you never want to run anything to the max, it tends to fail sooner if you do.
 

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Aside from a compound arrangement (that has it's advantages, particularly on the diesels), the only advantage to a twin/multiple turbo setup is sometimes it fits in the chassis better - and/or - it looks cooler.

The sequential/twin turbo setups in the jap cars of the 1990s was designed to prevent the pronounced "hit" of the turbo coming up on boost, and instead, provide a smoother transition into boost that felt more like a bigger NA engine instead of a smaller, turbocharged one.
 

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Most people switch to a big single because you can spool the big single to full boost faster at 700whp than you can with twins (unless it's sequential - but that take a lot of time and money to get the tuning right). I know only of 1 person right now that prefer sequential and he makes 700+whp on his supra (look up Stu Hagen). Even on stock twins that are in TTC mode, you don't get full boost until almost 5k rpm (don't start building until 3.5k to 4k rpm - ask me how I know) and you top out at 6.5k rpm maybe 7k . The powerband is not that great to support twins, whereas a single with the right tuning, you can get spooling as low as 2.5k rpm and full boost 3.5k to 4k all the way to 7k at 700whp. Plus, it's a ton cheaper single tuning is a lot easier. Also, to diagnosis sequential when it goes out is a pain in the ass so that's also why most people switch. Lastly, you never want to run anything to the max, it tends to fail sooner if you do.
2.5k? that's pretty good. Most of my fun will be on the highway but I still want a little fun in stop and go traffic too.
 

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Aside from a compound arrangement (that has it's advantages, particularly on the diesels), the only advantage to a twin/multiple turbo setup is sometimes it fits in the chassis better - and/or - it looks cooler.

The sequential/twin turbo setups in the jap cars of the 1990s was designed to prevent the pronounced "hit" of the turbo coming up on boost, and instead, provide a smoother transition into boost that felt more like a bigger NA engine instead of a smaller, turbocharged one.
yeah i was thinking about a compound I can't find too many people who's done it to make a fair comparison. The couple turnkey setup guys I'm looking into says there's no need so.
 

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Your biggest issue is finding a tuner that is able to tune that setup and a ECU that has the capabilities to do that setup also/. I only know like few selected tuners that is willing and good at doing that setup.
 

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Your biggest issue is finding a tuner that is able to tune that setup and a ECU that has the capabilities to do that setup also/. I only know like few selected tuners that is willing and good at doing that setup.
Drop me some recommendations then.
 

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Lance from Tune by Lance in FL (Use to own Toyomoto - specialized in IS300). Ishii Motors in WA (They tuned a 700+whp sequential Supra with Stu's help and inputs - Stu's Supra). Each tuner likes specific ECUs to work with.
 

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Lance from Tune by Lance in FL (Use to own Toyomoto - specialized in IS300). Ishii Motors in WA (They tuned a 700+whp sequential Supra with Stu's help and inputs - Stu's Supra). Each tuner likes specific ECUs to work with.
Yeah I'd guess I'd have to ship my engine then.
 

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Lance from Tune by Lance in FL (Use to own Toyomoto - specialized in IS300). Ishii Motors in WA (They tuned a 700+whp sequential Supra with Stu's help and inputs - Stu's Supra). Each tuner likes specific ECUs to work with.
What about some midwestern places like brangers racing?
 

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You'll have to ship the whole car....dyno tuning. I don't know that any midwestern places that can tune sequential.
 

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You'll have to ship the whole car....dyno tuning. I don't know that any midwestern places that can tune sequential.
Oh you're talking about specially dyno tuning. Oh ok only thing is I was trying to find a shop that engine build and tune it in case something goes wrong and I don't have one trying to blame the other then I'm pretty much out of money.
 

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Drag Int in FL can build it and they work with Lance on Tuning. Ishii Motors does both also...they do their own tuning and building.
 
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