1UZ twin turbo

[kingmick]

Sorry, I was thinking of 2 SC14's, but it was actually one SC14 running at double speed that Stu did the maths for.

That makes total sense then. wouldnt last long either at double speed.

[kingmick]

fixed, now no one knows what i said.
what are the sc14 from?

haha he said! JK

[MWP]

Sorry, I was thinking of 2 SC14's, but it was actually one SC14 running at double speed that Stu did the maths for.

Ahh.. that would make sense if his calcs were including efficiency.
I dont know why you would even consider doing that though, the SC14 would last 5mins before the seals let go.

In my EAP tests above, the belt ratio is set for max SC revs at ~6000 engine RPM.

[edit]
SC14s are off the 1G-GZE.
Can pick them up for $250-$350 ea.

[oldcorollas]

i think the situation might have been different that 2 SC14's on a 1UZ (maybe it was a single SC14 on 1UZ) and the reason we calc'd that was the holden kiddies always use the SC14 with mediocre results etc..
ie, on a 3.8L they use 1 SC14
http://www.rodshop.com.au/superchargerholdv6.htm
and they get 2-3.5psi, for a power increase of 25-30%
(all thanks to shitty VE of the original engine.. so it's kind alike an "assisted NA setup" as opposed to a FI setup)

1UZ, 2L/rev, assume 90%VE = 1.8L/rpm
SC14, 1.4L/rev X2 = 2.8L/rpm
2.8/1.8 = 8.2psi (assuming 1:1 ratio)
this is only ideal numbers, however, driving the SC's at 1:1, since SC rev limit is around 12-14K, you have plenty to spare in terms of RPM, so could up the drive ratio easily

however, you would still be limited the same way as a 1G is, in terms of air heating and how it flattens up top....
but low and midrange would be good! only issue is packaging...

[love ke70]

mm, these supercharger jobbies arnt small from what ive seen, im thinking if twin turbos are a squeeze then twin chargers will be too...
1 well sized turbo would not be all that laggy and provide good top end. all depends on turbo selection tho

[Wildsupra]

wow this thread went crazy.

2 sc14's would be the cheao option but would be limited to low boost, as they are on the 1G's, not really what im after. I need the potential for high boost when required.

I have been to look at 2 bolt on kits now for around $5500 one that runs around 7psi and one that runs around 12. However custom pulley will soon sort that problem out, once i find out what sort of displacement they cant acheive whilst staying efficient.

Im going supercharged for 2 reasons, one is to elimante huge amounts of lag, and the other is ease of fitment, let me remind you that i also have a crown with a 1UZ, wouldnt it be nice to be able to swap the setup to the crown from time to time

Cruzida i will be purchasing a soarer half cut to use.

The single turbo setup has already been done on 2 JZA80's that i know of, but yet so far no supercharged JZA80's.
The s/c setup should provide far better throttle response from a cruizing point of view, not too mention plenty of torque.

I checked that blitz site with no luck.
Cant seem to find any kits for sale on the net anywhere.
Need to beet the going rate of 5k ish

Matty

[oldcorollas]

what boost do you want? that will determine which type of SC you want.
simple roots<twisted lobe roots<more twisted lobe roots<twinscrew.

the mazda millenium used a twinscrew, the mini has an M45 iirc, M90's are on yank cars...

but mounting space will be your main issue.
fidn the SC sizes (from eaton site, or the lysholm site) make up a couple of foam lumps, then see if they will physically fit.
next issue will be mounting them solid enough, and getting good pulley wrap.

if you size the turbos small, they will have good response also... even 2 CT26's would work and be cheap.

[CrUZida]

Anything over 7psi and you will NEED intercooling, and you will NEED an aftermarket ecu.

All the 5-7k bolt on kits do not have provision for intercoolin.

[JustenGT8]

Yup, i disagree too.
SC14s will be cheaper to setup than turbos delivering the same high end HP/TQ figures.
SC's will be better too... no boost lag.

You figure? I think not on all counts

1) twin turbos will kill the SCs in all aspects of performance

2) Based on the presented modelling my turbos make MORE boost SOONER than twin SCs .....and totally slaughter them for peak hp!!!!!

3) 2 x Ebay specials on modded stock exhaust manifolds could be done cheaper than all the dicking around twin SC will take...brackets, belts, tensioners etc etc

Sorry turbos FTW

Do a proper SC setup and you'll have a weapon for pulling stumps but it's turbo every time for mine.

[MWP]

1) twin turbos will kill the SCs in all aspects of performance
2) Based on the presented modelling my turbos make MORE boost SOONER than twin SCs .....and totally slaughter them for peak hp!!!!!

The roots & twin screw (whipple) style superchargers make boost from idle. Instant torque.
As for high HP numbers, just use a bigger supercharger.
How can a turbo possibly beat boost available at all RPMs?

I still want someone from the "i love turbos" camp to explain why all insane drag cars use superchargers instead of turbos.

3) 2 x Ebay specials on modded stock exhaust manifolds could be done cheaper than all the dicking around twin SC will take...brackets, belts, tensioners etc etc

I dont believe so.
I know i could DIY a SC14 setup much easier & cheaper than i could a turbo setup.

[love ke70]

i wanna know why you havnt noticed almost all but top fuelers are now running turbos in drag racing....

[oldcorollas]

but a proper belt setup has to be spot on or it will slip or kill belts...

as for drag racing... thats the rules no? heck you can't even run twinscrews in topfuel...
and it has to be mechanical injection no? ie TPS based only..
SC is very simple for the amount of boost and amount of fuel they use also...
SC is also more predictable, since oyu have fixed volumes being moved.. turbo is more complicated, since you have variable volumes, and wastegate flows etc...
not all of the drag racing crowd are at the forefront of technology (and SC's are arguably more reliable in that arena)

i like thinking of it as...
an SC car is set up to run at full bore all the time, but you throttle it back..
a turbo car is usually only partially working, and goes that extra bit when needed...
crap explanation, but it depends what you want from the car.

dunno abotu the DIY for SC being cheaper? if you can make your own pulleys, that is a big plus!

[Joshstix]

I still want someone from the "i love turbos" camp to explain why all insane drag cars use superchargers instead of turbos.

A) Rules, turbo's are not allowed in the vast majority of motorsport classes

B) The people running the teams are old school and stick with what they know works

Damn that was quick.

[oldcorollas]

what he said /\/\/\/\

i wanna know why you havnt noticed almost all but top fuelers are now running turbos in drag racing....

pro-stock is NA
funnycars/doorslammers are SC...

it depends on the classes...

what do you mean nearly all cars in drag racing are turbo?

[JustenGT8]

The roots & twin screw (whipple) style superchargers make boost from idle. Instant torque.
As for high HP numbers, just use a bigger supercharger.
How can a turbo possibly beat boost available at all RPMs?

I still want someone from the "i love turbos" camp to explain why all insane drag cars use superchargers instead of turbos.



I dont believe so.
I know i could DIY a SC14 setup much easier & cheaper than i could a turbo setup.

It's your modelling mate, i'm just quoting the boost versus rpm results you presented?? and based on the ORIGINAL statement of twin SC14's MY turbos make more boost earlier and more hp?? who cares about a bigger SC this isn't what we are talking about?

Having said that though, i have driven a 4AGZE and no way was it full boost at any revs. Look at the boost plot that even toyota provide and (as per your modelling) you still need revs on board to get that instant full boost with throttle happening.

Turbos versus SC has been done to death, not going there again

Which is cheaper we'll never know then eh because i'm positive a simple TT setup would be easier one of those agree to disagree i think? Alot more turbo setups out there than twin SCs though