I've been trying to find out if the 7M is better than the 1jz and vice versa. I dnot like the idea of a huge twin because of the obvious low end power and drivability reasons. I think two medium sized parrallel snails would spool quicker and still make big power. Has anyone put twins on a 7m? If I got a 1jz(after I get a Supra of course) It would eventually become 3.0 Liters, I've even heard talk of the 3.4L stroker kit. I was thinkin a USDM SC300 bottom end. Alas, back to the focus of this thread, Are there any TT 7Ms around? or fo the price and ECU problems would it be better to start off with a 1jz?
Are there any Twin Turbo 7Ms?
- Thread starter Dexter_n2o
- Start date
Yes, it's been done, the proof has been trying to sell on ebay for aobut a year now ahahaa. Seriously tho, check ebay, there's a Saard kit and an HKS race twin manifold both for the 7m. Here's some pics of other twin setups.
eric
eric
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Exactly, I may have just enuff for a 1jz swap when I sell my lude combined with income tax, and some of that maybe the purchase price of a Supra. A TT 7M is waaaay more than a 1jz with BPU.
i dont think its that bad considering
1000 for a body (decent shape one)
1700 for a 1jz motor
200 or so for misc parts
sounds like you dont know much bout supras or swaps so im guessing you will get the harness extended to work which is about 500 ish for a good one, and then still pulling the 7m out and putting the new motor in.
its not a simple thing there but neither is a twin'd 7m
as for a 3.0 1jz....dunno bout that one.... theres a stroker kit for the 2jz for about 7k iirc and im guessing its going to be about the same if you can get one around here.....
1000 for a body (decent shape one)
1700 for a 1jz motor
200 or so for misc parts
sounds like you dont know much bout supras or swaps so im guessing you will get the harness extended to work which is about 500 ish for a good one, and then still pulling the 7m out and putting the new motor in.
its not a simple thing there but neither is a twin'd 7m
as for a 3.0 1jz....dunno bout that one.... theres a stroker kit for the 2jz for about 7k iirc and im guessing its going to be about the same if you can get one around here.....
I'm learnin. THe only thing I'vd swaped so far (in the process) is a Prelude engine. Pulled the carbed one, put a DOHC head on the carb'd block, Then I stripped the timing belt tensioner hole. Its just gettin to be to much trouble. Plus I've wanted a Mk3 for a long time.
NOw, back to the subject, I take it turboind these cars aint like a Honda, Get someone to make a manifold, Buy a turbo, get someone to do the pipng, chip an ECU and download uberdata and tune away. I'm pretty sure there would be ECU problems goin twin on the 7M. I cant really afford a stand-alone, and you cant just chip Supra ECUs and download a progeam to tune them (right?)
NOw, back to the subject, I take it turboind these cars aint like a Honda, Get someone to make a manifold, Buy a turbo, get someone to do the pipng, chip an ECU and download uberdata and tune away. I'm pretty sure there would be ECU problems goin twin on the 7M. I cant really afford a stand-alone, and you cant just chip Supra ECUs and download a progeam to tune them (right?)
I thought about that also. Im going to have ot research it more.I don't think I'll have the funds for that. At least not at the time I'm planning on doing the swap.
Dexter_n2o said:
single turbo is better if u ask me !! twins to much to worry about , + from what i herd single turbo spools up faster n is more reliable!!!
Big singles take a long time to spool. Look at a few 500-1000HP single turbo dynos, looks like a low rising hill till around 5-7kRpm and then its a really steep slope.the twins would make a lot of power down low, or at least more than one biggie. and have much better throttle response.
And you may be thinking of the Mk4 TT's where one turbo spools first then the other. Yes that setup(called a sequential setup) has to have all kinds of gates and actuaters, and a computer to control it all. The Mk3 twins spool together, 3cylinders to one turbo.
And you may be thinking of the Mk4 TT's where one turbo spools first then the other. Yes that setup(called a sequential setup) has to have all kinds of gates and actuaters, and a computer to control it all. The Mk3 twins spool together, 3cylinders to one turbo.
Depends. On the TT supra there are two same sized turbos. There is an assembly that directs all 6 cylinders' exhausts to one turbo. At a certain rpm/boost level(not sure which) the gate is opened and both turbos provide boost.
The Ferrari F50 has two different sized turbos.
Both of these cars use what is called a sequential TT setup. However,
In a parrallel setup such as the 1991 Toyota Supra 2.5TT, two same sized turbos are driven by 3 cylinders apiece. For this setup you can use two smaller turbos that will spool quickly and still make good top end power.
This is in my opinion the best choice for a high HP street driven car. You get down low torque, good throttle respone, and top end.
Say that single turbo is rated for 1200HP @30psi. Two smaller turbos that make 650HP@17Psi will spool quicker and the max out will be higher. Theoretically they will spool almost twice as fast.
The Ferrari F50 has two different sized turbos.
Both of these cars use what is called a sequential TT setup. However,
In a parrallel setup such as the 1991 Toyota Supra 2.5TT, two same sized turbos are driven by 3 cylinders apiece. For this setup you can use two smaller turbos that will spool quickly and still make good top end power.
This is in my opinion the best choice for a high HP street driven car. You get down low torque, good throttle respone, and top end.
Say that single turbo is rated for 1200HP @30psi. Two smaller turbos that make 650HP@17Psi will spool quicker and the max out will be higher. Theoretically they will spool almost twice as fast.
Actually, two small turbos would spool quickly, but unless they are sequential, you only have 3 cyls spooling them. So if you have two "smaller" turbos that make 650; sure they'd spool relatively quick with a 3 liter pushing one of them, but cut that in half, and you have a 1.5 liter honda trying to spool a 650 hp turbo. It's not going to happen quickly or early in the power band. One single will spool faster because there is only one rotating assembly to accelerate up to speed. The best way to run twins is like the mkiv does it. If you use an MSD window switch, you can spool your 650 hp turbo off of all six, and then when 4K rolls around, pull 3 cyls from turbo A and send them to spool your second 650 turbo and end up with 1300 hp potential with 650 hp spool.
It's not easy, the plumbing is messy. and you won't make 1300 hp with messy plumbing, because all of the little inefficient bends start robbing power and adding backpressure before the turbo.
Go with a good sized Ball bearing single, and it will spool fine, and give yo uplenty of balls.
Just my 2 psi
It's not easy, the plumbing is messy. and you won't make 1300 hp with messy plumbing, because all of the little inefficient bends start robbing power and adding backpressure before the turbo.
Go with a good sized Ball bearing single, and it will spool fine, and give yo uplenty of balls.
Just my 2 psi
I had this stuff straight in my head once, the benifits of twin sequential over big single. I had researched why VW uses 4 turbos on its W12 and also on the Buggatti W16. I know the Buggatti Veyron 16.4 makes over 900Ft.Lbs. of torque at like 2200rpm. the max HP is 1001. Ya'll have me thinkin about a crazy manifold were all 6cyl drive both turbos. Dont know how efficiant it would be. it would almost have to be like two tubes from each cylinder, one to each turbo. I just dont think there's enough room
A twin setup is a smoother boosting setup.. a large single is more abrupt when it hit's boost. twins are much more tractable... that being said.. i run large single i like the power delivery
dude f50s are not turbo. Sequential turbo setups like the mkiv are overrated, or theyve yet to be perfected. There is a flat spot in the powerband when they switch over, the second turbo surges and dies rather quickly, whereas parrallel just hits and pulls to redline. Equal stress, equal work on both turbos. In japan the 2jz and 1jz turbos are setup parallel because they spool faster and pull harder that way. In North America the market demands low end torque from the days of old domestics.
Twin turboing a 7m is pointless IMO other than the "wow" factor. Dont even bother comparing supercar setups to that of a 2xx hp car that you plan to modify.
Twin turboing a 7m is pointless IMO other than the "wow" factor. Dont even bother comparing supercar setups to that of a 2xx hp car that you plan to modify.
F50s or F4os, one of them is TT. Anyway, I know that sequential is overated. I'm gunning for the benifits of parallel twins compared to one big single. The convo got a lil sidetracked. Once you get 300+Ft.Lbs. its still a lot, its just where in the powerband it comes.
Thats what I think the benifit is, lower torque urve with the twins.
Thats what I think the benifit is, lower torque urve with the twins.
Twins are marginally more responsive than a single, that's why OEMs use them. But an OEM is playing with a completely different set of rules than a guy in his garage. They've got economy of scale on their side; the additional cost and complexity of using two turbos is quite a bit different than what we'd pay for the additional hardware. They're designing the car from the ground up and can easily change the layout of the engine compartment to accommodate the additional plumbing. They've also got an army of engineers to figure out how to make it all to work reliably and efficiently. I'm not saying it can't be done (it certainly can) but a guy in his garage operates quite a bit differently than a company with 1000+ engineers on their payroll, huge fabrication shops staffed with F1 race car mechanics and a multi billion dollar R&D budget.
I can see using twins on a V engine to simplify the plumbing, but we have an inline engine. Personally I'd be looking at boring and stroking the 7M to 3.3 liters to improve bottom end torque and spool up before I messed with a twin turbo setup on an inline engine.
I can see using twins on a V engine to simplify the plumbing, but we have an inline engine. Personally I'd be looking at boring and stroking the 7M to 3.3 liters to improve bottom end torque and spool up before I messed with a twin turbo setup on an inline engine.