Single T or TT

[GT500916]

The twin turbos on a supra run at 8psi promary and 11psi secondary am i correct?

when you get a boost contol do you only need one or 2 for individual turbos? or do they both bost up with one control and how so?

Which is better single or TT? TT has less lag and the secondary give the top end, but the single turbow give more top end power but some turbo lag? wich set up is better and why?

Whats the stock A/R size on the twin turbos and whats the A/R size of a single turbo supra...

Were most supras made with twin or single turbos? and how can you tell which are single and wich are TT without looking under the hood?

what can stock turbos run? up to 15 psi? and what can a stock supra engine produce? about 400-500 hp?

im just learning about supras and im looking to buy one sometime next year 93+

[flyinMKIV]

lots of questions young grasshopper, lol sorry couldn't help myself. OK. The TT setup runs on a sequential setup where as one turbo works, then the secondary works after it. You can run them in a parallel system which is they both come on at once but very laggy. On which is better, a TT or single, it really depends on what your wanting to do with the car, I prefer a single, but a quick spooling turbo, it creates more power without as much lag off the line, which is optimal for running 1/4 mile runs. There really isn't a way to tell if a car is a single or twin turbo setup without looking unless it's a promod car with a big turbo sticking out of the hood. On a twin turbo setup, you can run up to 18psi safely and 21psi on race gas (ex. 116 octane) A stock supra turbo motor (2jz-gte) can produce in the range of 800-1000hp (with the supporting mods such as a fuel system, turbo, etc.) and that is on stock internals such as the pistons, rods, etc. If you have any other questions, feel free to ask on here, I'm not sure about the a/r sizes but I'm sure MKIV.com will have that information for you, if not I can get it out of my manuals and mail it to you if needed. Good luck on finding your car Later

[GT500916]

Originally Posted by flyinMKIV

lots of questions young grasshopper, lol sorry couldn't help myself. OK. The TT setup runs on a sequential setup where as one turbo works, then the secondary works after it. You can run them in a parallel system which is they both come on at once but very laggy. On which is better, a TT or single, it really depends on what your wanting to do with the car, I prefer a single, but a quick spooling turbo, it creates more power without as much lag off the line, which is optimal for running 1/4 mile runs. There really isn't a way to tell if a car is a single or twin turbo setup without looking unless it's a promod car with a big turbo sticking out of the hood. On a twin turbo setup, you can run up to 18psi safely and 21psi on race gas (ex. 116 octane) A stock supra turbo motor (2jz-gte) can produce in the range of 800-1000hp (with the supporting mods such as a fuel system, turbo, etc.) and that is on stock internals such as the pistons, rods, etc. If you have any other questions, feel free to ask on here, I'm not sure about the a/r sizes but I'm sure MKIV.com will have that information for you, if not I can get it out of my manuals and mail it to you if needed. Good luck on finding your car Later

thanks for reply the old mighty wise man! wow 800-1000 on stock internals!!! #$#@#$@ now i want one bad!!! my 240 can only handle 400 on stock internals and i thought that was huge power hahaha.... never knew supra engines are so strong stock....

I did notice that most supra owners have single turbo, is it because they upgrade to single turbo or is it because they made more single turbo supras or TT supras?

You said its safe to run at 18psi, now is that on primary turbo or secondary turbo? and is there a way to adjust both differently or they both adjust by one switch to different PSIs? and what would be approximate hp running stock engine with stock turbos at 18psi?

you said the parallel system, its not stock this way on a twin turbo am i right? so why would someone change that to a parallel system and get more lag? do they gain more top end power?

Honestly im not gonna do much with the supra because they are fast as heck stock with a turbo... so i dont think i will be upgrading turbos no matter if its single or TT...

I was going to put a turbo on my 240 and rebuild the internals and be happy with a 13 sec car... but since i live in CA and greddy doesnt make a turbo thats CARB legal so that would suck if i got my car impounded... so i was gonna build up my own turbo and hide it as good as possible, but it will still be risky you know what i mean? and i just wont enjoy driving my car everyday being all illegal and me being all worried about cops every where i go... i want to actually enjoy driving a fast car and be perfectly legal, and supra is the only one of a kind and ill pass smog and inspections, and will be good to go and have the power to play with.

[Chuki_breath]

hmmm dont no much about the supras but 93+ is the new body styles right?? i say good luck finding one and with all the money you put into buying a stock supra a 240 would waste it. thats just me though. But a supra definently has hecka more potential. Maybe i miss understood you, it sounded like you want just a stock supra with no mods??? But a supra isnt cheap. Yes there fast stock but there not that fast stock. I mean you'll still run into your comaros and stangs that can easily beat a stock supra. I say stick with the 240 to be honest, not to mention the insurance rates on a supra.

[nissanfanatic]

Turbos don't work like your thinking. If you have two turbos flowing say 15lbs at 5psi, that doesn't mean a total pressure of 10psi. It means you're flowing 30lbs at 5psi. Exactly why a small turbo will not make as much power at a given boost level as a larger turbo. I believe the thing on the sequentials is one turbo is efficient at a given flow and the secondary is efficient at a higher flow. Or they use some kind of bypass system. i have also heard that one turbo is more efficient than two. Not sure on that one though.

If you can get your hands on a supra, I would go for it. Supras are teh sex, but I mean you'll never have to upgrade internals. Not to mention the millions of parts, HP potential, and they have pretty good handling and great braking.

[AWDSR20]

the good
supra = sexy
supra = Fu$Kn fast (turbo!)
the bad
supra = fat
supra = not nimble
supra = $$$$ (not for power, just the cost of buying one)
supra = $$$$ to fix anyting

[logik23]

I'm pretty sure all MKIV Supras were either twin turbo or no turbo. Only the MKIII (or earlier, I dunno) came with single turbo. Single turbo MKIVs must be a mod.

[2of9]

like flyinMKIV said, Single Turbo is better for 1/4 wise and twin turbo is better for the topspeed, especially when you have 2 T78 TURBOS IN A SUPRA!!! hahahha...has any ever done that IN a street Supra?

[SR20DETpower]

Id get a 300zx twin turbo before a Supra as far as pricing goes, and they are both nice cars

[GT500916]

Here are the reason why im looking into buying a supra...

1.Turbo stock, so passing visuals and no need for CARb sticker like putting a turbo in a 240... greddy doesnt even have a CARb for them yet!! so i wont be turboing my 240 anytime soon probably never...
2. runs 13.5 1/4 stock
3.No internal work needed to gain massive amounbts of HP
4.Straight six not V6, so more room to work on and less complicated
5.just sooo sick looking haha...

the price part is what ill have to look around for, im looking at about $15k if im lucky...i will be replacing rings and rod bearings if high miles on it...

by the way anyone know how reliable supras are with turbos? because i know cars like eclipses that come stock with turbos dont last more than 70-80k because engine has lots of stress on it...

[TcmaBoy]

If I remember correctly the stock MK IV turbo system was a sequential setup. It used a bypass and wastegate control to divert exaust flow to the turbo that needs it. At low engine speed most of the flow is diverted to the small turbo to spool it quickly. As it reaches peak flow is diverted to the larger turbo to begin spooling it. The two are matched so that as the small turbo is running out of breath the large turbo is spun up. Exaust flow is cut to the smaller turbo so as not to exceed its limits. It delivers the best of both worlds. The only problem is it is complex. Parallel twins are simple, and offer better low end boost. You can use small turbos togeather to deliver the needed volume. This gives good low and midrange, but top end is limited. A large single turbo will give the big HP numbers but you will need to wait untill about 3500 RPM to see any power. I belive the boost controllers for the stock MK IV turbo system affect both turbos equally, but I'm not sure. They usally work by modifying the boost reference signal to the wastegate actuator. You can milk over 400 HP out of the stock turbos with a little tuning. I'm not sure how carb feels about piggy back electronics, but they are way too easy to hide in they don't like em.

I saw someone said that supra=not nimble. HA! I have seen plenty of articles on MK IVs pulling 1.0G+ on the skid pad. Thats supercar grip my friend. Not to mention the Supras dominance of the JGTC for the last decade or so. Thats a field that includes not only Skyline GTRs, but there are also a few McLarens and Ferraris in the field. Supras stick.

[GT500916]

how much can a stock TT supra last mileage wise? lets say its an average driver and oil has been changed when needed to be changed... how reliable are they? can they go over 100k with no problems? 200k possible? ... i know toyotas are made to last and outlast all the cars, but how true is this statement for the supras?

at what milage would it be a good idea to replace the rings and the rod bearings? 100k+?

[TcmaBoy]

It should last at least 130000 miles, unless you really abuse it.

[GT500916]

so lets say i get a 130k miles turbo supra i should probably put new rings in and rob bearings and bore it .20 over, or dont bore just do the rings with bearings?

what u guys suggest for a high mileage TT?

[flyinMKIV]

stock turbos tend to last about 100k for a new rebuild or upgrade, it depends on how they have been treated. MKIV Supras only came as a non-turbo with ethier a auto tranny or 5 spd and the twin turbo supras came in ethier a 6 spd or auto tranny as well.