twin turbos or single
 

Hey everyone i was just gonna get peoples opinions to see if it is beter to upgrade your two twin turbo or if it better to go a large single. and what would be the easiest way to make some hp

Cheers Dylan

It really depends on what u are looking for! Twins have a lot less spool time especially with the stock sequential. The beauty of that system is you use the rear turbo which is smaller up to a certain point and then the front bigger one kicks in for higher HP at high rpm with out "falling off" which for a daily driver that is a wicked setup. And they are quite durable compared to other stock turbos.

How much boost you looking to run?

A way to common mistake people make is over size there turbo and end up loosing HP they could be getting sooner due to added lag.

I personally like twins! But as u can see in my Sig on my 1j I'm running a 60-1 single. That is because 1j stock turbos are crap. And mostly cuz i drag race with the car. Also let's face it turbos are far from cheap. And if you only have to buy 1 as oppose to 2 well you get the idea

cheers for the help mate. i havnt actually got my car yet but towards the middle of the year i will be getting one. Im not actually sure how much psi to run. some people dont like to touch it and other people i have talked to have put the psi up. what would u reccomend for the size of a single turbo and how much would you run through yours. When im finished with it, it has to be able to beat a r32 gtr haha :) but i want a reliable every day car aswell

thanks

Actually both turbos are the same size. Common misconception. In fact, Toyota even produced some (incorrect) marketing literature stating that one of the two turbos is bigger. In fact, the two same-size turbos working together produces the increased amount of compressed intake airflow.

You run as much PSI as the fuel you're running will support. With 93 (R+M)/2 pump gas, that's about 16psi. Anything more will slowly damage your pistons (measurable via compression/leakdown test). With race fuel (eg C16, you can run 30psi or more).
To beat an R32, you'll need several mods, including wider tires, a fuel system with bigger injectors and multiple fuel pumps, a bigger turbo(s), and a fuel controller or aftermarket ecu. If you have an auto transmission on your Mkiv TT, you'll need to get that modded. With a 6spd, you'll need an aftermarket (eg. twin disk) clutch.

There's no good twin turbo upgrade kit I'm aware of that maintains the oem sequential operation. In general, your cheapest option ($ per hp) will be a single turbo upgrade.

Hey Phil. Can you take a look at this thread for me and give your opinion on it? I'd appreciate it.
http://www.toyota-supra.info/forums/...lp-please.html

ok cheers for the help guys. i was wondering how to beat a 32 because my brother has one haha and he rekons that i wont be able to get my power to the ground. after i get a bit more horse power (say 450hp) would it be very difficult to get my power to the ground or will it just do a huge skid

Dylan

Not with the right rims and tires. Have you ever tried MT drag slicks?

hey just read the thread, im new here and don't know if its too late but is it possible to put the two stock turbos from a 2jz-gte onto a n/a engine, as i have just bought a 94 supra and it would be good if i could do that. So is it possible and what kind of work would need to be done?

Nope, the manifold the oem twins mount on doesn't fit the 2jz-ge head. In theory I guess it's possible with a ton of custom fab work (weeks and weeks, and thousands of dollars - really!), but it definitely isn't practical.

Your only practical options are:
1) Sell your n/a and get a true Mkiv TT (this is by far your best option, since you get all the braking power, suspension, and bulletproof drivetrain of the TT - not just the turbos).
2) Put a complete n/a-T kit on your n/a (which upgrades your turbos, your fuel system, head gasket, head studs, and your ignition). After that, you'll have to figure out how to upgrade your braking system (calipers&rotors, bmc, abs system, etc), suspension, transmission and and differential...when all priced out with labor will cost you more than the difference between a used TT and a used n/a.

In my opinion singe turbo is cheaper and if you go full out makes a good drag motor, twins are more expensive and more suited for like auto cross and street

well i already got an N/A and it was a lot cheaper then a TT, I want to get around 500/550hp out of the engine. What would need to be done and how much do you guys think it would cost. And have any of you done this with your car, what size turbo are you using, how much power , how much did it cost you?

What do you think of the na-T kit I linked to in my post above?

What are you planning to do with that 550hp? Drag race? Road race? Autocross? Drifting? Top speed? Highway races from a roll? ...just curious.

Do you mean sequential twins, or parallel twins?

I think sequential is more practical for like road racing auto cross and street, a parallel system is for like highway rolling starts and drag

You have been misinformed - the oem twins have been drag raced in both sequential and parallel modes, and sequential is faster for drag racing too.

Here's how to put the oem twins into parallel mode:
http://www.mkiv.com/techarticles/ttc/ttc.htm

Ok so maybe 550hp is too much, i found out the stock TT can only go to around 400hp, and im not drag racing it or anything, at least not now. Just want to make it more powerful and fun to drive in the future. So im guessing say 450-500 is more suitable, i don't know really it all depends on how much i pay for the parts and whether it may be just a little bit more pricey for more power?

You also have been misinformed. If you're truly interested for whatever reason (given that you're an n/a owner) "the stock TT" can do a lot more than "400hp". That said, 'the stock ZR1 vette' can do 638hp...to me, that's just as irrelevant! The n/a MKIV and TT MKIV engines are completely different - with totally different heads, different pistons and a different ignition system!!! It seems that you arbitrarily want one to suddenly do the same hp as the other one. Why not evaluate what the n/a MKIV engine is capable of all on its own right, independent of what any other completely different engine/car/whatever can do? Also, if you want what the TT can do in horsepower, how are you going to stop all of that quickness once it gets going? With those pitiful n/a brakes? What about turning with the lousy n/a suspension and narrow 16" wheels? What will you do when the weaker n/a transmission or the weaker n/a differential gives up the goat?

Lastly, you never answered my question: What do you think of the n/a-T kit I linked to in my post above?

I only really want to know how much the GTE can make as I have heard it can do around 400hp but if more i may consider swapping the engine with a TT or buying a TT supra with the big brakes, abs ect. Other wise with a single turbo kit, i can fit bigger then UK brakes myself or find a used US/UK spec set. I also plan to fit aftermarket coilovers, and i have a set of 18" wider wheels already. I may swap the gearbox and drivetrain out of a wrecked TT or something if I don't get a TT supra. Regarding the single turbo kit, it is a bit pricey, also parts like the intercooler and other parts i can buy separatly with better specs, and reduce the price of the whole upgrade.

1) You have to precisely match the intercooler size/"specs" to the turbo size. An intercooler that is too big will introduce additional lag. The intercooler in that Boost Logic kit is precisely matched to the turbo size, so anything with different specs won't work as well.
2) A cheap ebay intercooler is just that - a cheap intercooler. Most likely fitment will be poor, the kit won't be complete, and the poor-quality welds will split and/or leak boost.

With the oem twins, the highest hp I'm personally aware of (verified) for a 2jz-gte in an Mkiv Supra TT is 570hp (485rwhp). This was on brand-new turbos, a brand-new engine, bpu+++++, and dyno'd at sea level on a very cool day. I've actually heard of even higher levels by pro race teams who did extensive porting&polishing,etc. to the turbos, manifolds, intake & exhaust ports, etc. I agree that a 2jz-gte swap would be a great option for you, if you can find one with very low miles&hours.

Oh, and of course with an aftermarket turbo kit, fuel system, cams, ecu, etc., the oem 2jz-gte (bone-stock internals) is good to about 1200hp (1000rwhp+). The oem TT transmission and the oem TT diff can easily handle that hp level too.