Turboing a GS400 Questions?
06-17-08, 01:42 PM
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Turboing a GS400 Questions?
I'm interested in doing this, but I don't want to do major internal work to my engine. What will a stock GS400 motor hold(ie how much boost?) I know the trans is a weak point, but I've already rebuilt mine! I have modest goals. Would like to be about 400-450 rwhp......what are your suggestions to get there??????? Should I go single or twin??? How will it hold up?? This is my DD! I had a STi and miss the boost! 
Plus I love spanking everything on the road!(not just 98% 
)
oh...and if it matters my 99 only has 60K miles on it.
Plus I love spanking everything on the road!(not just 98% )oh...and if it matters my 99 only has 60K miles on it.
Last edited by kevs98GS4; 06-17-08 at 02:05 PM.
06-17-08, 02:29 PM
#2
the cost of rods and pistons is minimal to the cost you will incur fabricating a turbo kit for that motor, does anyone even make turbo manifolds for the GS400? Put on a supercharger, or get a GS300.
06-17-08, 02:50 PM
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don't want to use a supercharger.....why use power to make power when you can use something already coming out of your exhaust?! I also know there are several people here running turbos on their 400! That's why I'm asking.
06-17-08, 03:16 PM
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06-18-08, 05:27 AM
#8
....pay to play....pay to play...damn! It's just that you have to pay MORE (with certain cars) to play the same with others. I love my GS400 but I think there are a lot mor cars on the market that will "take to" turboing a lot better for MUCH less money. Why don't you just try to be different and drop $10-12K and speak to Lextreme from making your 4.0L into a 4.7L or 5.?L!!! You will be a MONSTER N/A then and probably be just as powerful if not more than a supercharged GS4. Just my 2 cents...GL Kev!
06-18-08, 08:23 AM
#9
instant torque, no lag, instant HP, cheaper...
Nobody is going to spend tons of money fabricating a turbo kit to skimp out on pistons and rods.
06-18-08, 01:18 PM
#13
maybe for the manifolds, turbos, wastegates, exhaust, BOV's, etc.. but then you need a fuel system, stand alone, tuning, intercooler, pistons, rods, overhaul the engine and head, boost controller, ignition, etc.. the list goes on and on. I'm currently doing my GS300 to make about 800RWHP, it isn't cheap... oh you need a tranny, custom driveshaft, rear end with LSD. There is so much you have to do to these cars to make the big power, and that is with the GS300 which basically has the block, crank, head, etc. already in place, the GS400 would be a money pit to turbo.
06-18-08, 01:35 PM
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If you are going to keep stock internals, then you may not be able to boost higher than 8-10 lbs. Keeping the boost at 10# is living on the edge for a daily driver. Your pistons will crack usually due to the ring lands being so thin. You definitely need some sort of fuel control and preferably also timing control to make the car run safely. I have spent too much on my TT setup, and am in the process of rebuilding everything, NOT because something is wrong, it's because I want more.
If someone quoted 30-40k for a build, I would rather just call TTurbopimp and offer him 30-40k and see if he'll sell the car. I wouldn't spend that much on a TT build. Building a TT 1UZ is not common like a TT 1JZ. But if you ask most of us with the TT GS4, it's done because it sets us apart from the TT GS3/1jz fellas. The 1jz has many performance parts out there, the 1-3uz's don't so when there is a performance part, it usually is expensive. The 1JZ have shown great numbers for HP. It's just a preference if you want a 6 or 8 cylinder beast.
If someone quoted 30-40k for a build, I would rather just call TTurbopimp and offer him 30-40k and see if he'll sell the car. I wouldn't spend that much on a TT build. Building a TT 1UZ is not common like a TT 1JZ. But if you ask most of us with the TT GS4, it's done because it sets us apart from the TT GS3/1jz fellas. The 1jz has many performance parts out there, the 1-3uz's don't so when there is a performance part, it usually is expensive. The 1JZ have shown great numbers for HP. It's just a preference if you want a 6 or 8 cylinder beast.
Last edited by HI98GS; 06-18-08 at 01:50 PM.
06-18-08, 10:30 PM
#15
Very long post, but worth a read.....
No matter how you slice it. You're gonna be spending a butt load of money to boost a GS. It's expensive to turbo any factory NA car. The GS400 is just really really expensive to boost lol. BUT it sure is a unique project
Now, thats just to boost it. I didn't say anything about high power levels. That's a whole different level. Consider my experiences...
I do all the work myself and this is on a GS300 with 2JZ that has very commonly available upgrade/performance parts. A GS400 will have to have many of the parts custom fabbed from scratch which is $$$$$$.
My initial NA-T setup: Approx $2500 in parts to get me to around 280-300whp.
A little later I did a few upgrades to get a bit more power: headgasket, fuel system, new piggyback, and some other various small things. That was about an additional $1500. At this point I have about 350-375whp or so.
Now onto the big build where I swapped in a 2JZ-GTE motor, built auto transmission, AEM EMS standalone engine computer, monster sized fuel system. This upgrade cost me roughly $5000 in parts alone. It was also very labor intensive, but good thing I did all the work myself. This put me at the 500whp mark, limited by the turbo...the rest of the engine is capable of much more. If you took it to a shop to replicate my setup, the labor would be around $10,000 in additon to the parts cost.
Next step is to slap on a bigger turbo which will cost about $2000. That will get me to around 700-750whp IF and I really do mean IF the transmission will hold up. It's actually a matter of how long it will be before the transmission blows, not IF it will. When the transmission gives out, I will have to upgrade to the 6 speed manual V160 transmission from the supra. Parts alone will cost around $7000 or so. But now the transmission is able to hold in excess of 1000whp. But the turbo is maxed out at that point and will require an even bigger turbo and bigger fuel system.
I think you can see where I'm going with this. Power is exponentially more expensive. To get you from the stock 180whp of the GS300 to 350-375whp will cost about $4500. From there on up, to gain that same amount of power will cost double an so forth.
Now...all that was on a GS300 with a 2JZ with commonly available upgrade parts that are going to be "relatively" inexpensive when comparing to those same parts for the GS400 V8. So tack on an extra 40% or so for rare or custom one-off fabricated parts. Also, with all the prices I listed it did not include labor.
Add all that up, to get decent power out of a GS400(600-800hp)...you are going to spend easily upwards of $30-40k. Even at milder(400hp) power levels you are still going to be spending around $15-20k for a custom fabbed turbo setup.
Then there is the last factor of who is going to do the work. It better be someone very experienced in building stuff for this vehicle and most of all they better be local to you. It will get old having to ship your car across the country everytime something goes wrong!
Just a few things to think about if you're planning to go out and be a pioneer. Not discouraging you or anything, just giving you a quick reality check
No matter how you slice it. You're gonna be spending a butt load of money to boost a GS. It's expensive to turbo any factory NA car. The GS400 is just really really expensive to boost lol. BUT it sure is a unique project
Now, thats just to boost it. I didn't say anything about high power levels. That's a whole different level. Consider my experiences...
I do all the work myself and this is on a GS300 with 2JZ that has very commonly available upgrade/performance parts. A GS400 will have to have many of the parts custom fabbed from scratch which is $$$$$$.
My initial NA-T setup: Approx $2500 in parts to get me to around 280-300whp.
A little later I did a few upgrades to get a bit more power: headgasket, fuel system, new piggyback, and some other various small things. That was about an additional $1500. At this point I have about 350-375whp or so.
Now onto the big build where I swapped in a 2JZ-GTE motor, built auto transmission, AEM EMS standalone engine computer, monster sized fuel system. This upgrade cost me roughly $5000 in parts alone. It was also very labor intensive, but good thing I did all the work myself. This put me at the 500whp mark, limited by the turbo...the rest of the engine is capable of much more. If you took it to a shop to replicate my setup, the labor would be around $10,000 in additon to the parts cost.
Next step is to slap on a bigger turbo which will cost about $2000. That will get me to around 700-750whp IF and I really do mean IF the transmission will hold up. It's actually a matter of how long it will be before the transmission blows, not IF it will. When the transmission gives out, I will have to upgrade to the 6 speed manual V160 transmission from the supra. Parts alone will cost around $7000 or so. But now the transmission is able to hold in excess of 1000whp. But the turbo is maxed out at that point and will require an even bigger turbo and bigger fuel system.
I think you can see where I'm going with this. Power is exponentially more expensive. To get you from the stock 180whp of the GS300 to 350-375whp will cost about $4500. From there on up, to gain that same amount of power will cost double an so forth.
Now...all that was on a GS300 with a 2JZ with commonly available upgrade parts that are going to be "relatively" inexpensive when comparing to those same parts for the GS400 V8. So tack on an extra 40% or so for rare or custom one-off fabricated parts. Also, with all the prices I listed it did not include labor.
Add all that up, to get decent power out of a GS400(600-800hp)...you are going to spend easily upwards of $30-40k. Even at milder(400hp) power levels you are still going to be spending around $15-20k for a custom fabbed turbo setup.
Then there is the last factor of who is going to do the work. It better be someone very experienced in building stuff for this vehicle and most of all they better be local to you. It will get old having to ship your car across the country everytime something goes wrong!
Just a few things to think about if you're planning to go out and be a pioneer. Not discouraging you or anything, just giving you a quick reality check
Last edited by JeffTsai; 06-18-08 at 10:47 PM.