Turbos

[TonyB]

A4L XR6 turbo will pull hard anyway because it has 4L, the low down torque in these cars comes from big cubes, your GT legacy probably has a little turbo to get it moving.

the latest Legacy GT....343 Nm at 2400 rpm.
the Legacy 3.0R SpecB ....297Nm at 4200rpm.
Current Ford XR6....380Nm @ 3250rpm
Current XR6 Turbo....450Nm @ 2000rpm

The Legacy GT has one big turbo and 2 little litres
The 3.0R has 3 litres, no turbo
The XR6 has 4 litres, no turbo
The XR6T has 4 litres, one big turbo
You will notice that the 2 litre turbo GT makes nearly that same peak torque as the 4 litre XR6 at much lower revs.
The XR6T will stomp all over the 5 litre XR8 until they hit maybe 4500
What are you calling low revs? Idle to 2000? If thats the case I agree with you.

[dangerous]

Hell BJ dont mean to be stalking ya but heres another quote....

I think speedpro has some 80's 1000cc turbo thingy.. Saw it once, the turbo sit just under your left thigh, and the pipes go just a bit further out. That looked mental. Think it was a Kawa come to think of it, but probably wrong about that too..

Yeah baby that bike is a Kawa Z1TC a late 70's Z1 (speedpros is a McIntosh framed beast tho) which kawa nabed a few as they went out the back door and bolted a simple turbo kit up to they suck the fuel mix through the turbo cos they are a carbed motor.
Kawa in the 80's built the GPZ750zx turbo (see Death's profile) which was the fastest mother of all the turbos with Honda's CX650 right behind it, as with the suzuki XN they were injected the Yamaha XJ650 was the only other carbed turbo from the japs.

Heres a write up on the CX500Turbo I had, all bikes should have one aye

BTW turbos are better IMHO cos they use wast energy to make power were as superchargers use power to make power

[Jeremy]

They don't put turbos on all production cars for a number of reasons:

1) They cost money
2) A large part of their market buys cars to get from A to B so they don't need massive amounts of HP
3) They increase the amount of maintence and engine needs. The top of the line EVO8 is an extreme example. Can you afford having to go into the mechanic every 3000km?

Anyway for more performance it may be far easier just to put in a lower range gearbox that has more gears. It'll get you to your top speed faster, and I'd a hazard a guess that it'd use less fuel.

[bugjuice]

what's that little Suzuki Cappachino thing run on? Something like 700cc and a turbo.. 2 seater convertable thing.. looks like a micromachine for real..

[HDTboy]

They don't put turbos on all production cars for a number of reasons:

1) They cost money
2) A large part of their market buys cars to get from A to B so they don't need massive amounts of HP
3) They increase the amount of maintence and engine needs. The top of the line EVO8 is an extreme example. Can you afford having to go into the mechanic every 3000km?

Anyway for more performance it may be far easier just to put in a lower range gearbox that has more gears. It'll get you to your top speed faster, and I'd a hazard a guess that it'd use less fuel.

and weigh more, and not increase the volumetric efficency of the engine

[HDTboy]

what's that little Suzuki Cappachino thing run on? Something like 700cc and a turbo.. 2 seater convertable thing.. looks like a micromachine for real..

660cc turbo, don't know a hell of a lot about it other than that

[HDTboy]

The Legacy GT has one big turbo and 2 little litres
The 3.0R has 3 litres, no turbo
The XR6 has 4 litres, no turbo
The XR6T has 4 litres, one big turbo
You will notice that the 2 litre turbo GT makes nearly that same peak torque as the 4 litre XR6 at much lower revs.
The XR6T will stomp all over the 5 litre XR8 until they hit maybe 4500
What are you calling low revs? Idle to 2000? If thats the case I agree with you.

I was assuming you had a twin turbo legacy, sorry i was wrong in that
My idea of low revs is the bottom half of the tacho, which for most common cars would be 0-3000rpm give or take
Ball bearing turbos do reduce the lag quite a bit and probably play a part in the observations which you've made
XR6T should stomp all over a 5L! even if you multiply by 1.6 its effective capacity is 6.4L

[TonyB]

I was assuming you had a twin turbo legacy, sorry i was wrong in that
My idea of low revs is the bottom half of the tacho, which for most common cars would be 0-3000rpm give or take
Ball bearing turbos do reduce the lag quite a bit and probably play a part in the observations which you've made

Nah, I have the twin turbo one. But the numbers I posted are for the latest single turbo version. I agree that a bigger engine is the way to go in the very low end, but you tend to drive in the middle of the rev range (on the open road at least) and this is where aturbo shines.
Ball bearing turbo's make a huge difference- my old mans Cefiro used to go amazingly well, almost no discernable lag and it pulled around 2000rpm. Then one day the turbo died- he reckoned it was like driving a Morri 1100! He then discovered it had a non servicable ball bearing 'sports' turbo. He went for the cheaper rebuildable version. It ruined the car- big lag coupled with an auto is not much fun...

[HDTboy]

Nah, I have the twin turbo one. But the numbers I posted are for the latest single turbo version. I agree that a bigger engine is the way to go in the very low end, but you tend to drive in the middle of the rev range (on the open road at least) and this is where aturbo shines.
Ball bearing turbo's make a huge difference- my old mans Cefiro used to go amazingly well, almost no discernable lag and it pulled around 2000rpm. Then one day the turbo died- he reckoned it was like driving a Morri 1100! He then discovered it had a non servicable ball bearing 'sports' turbo. He went for the cheaper rebuildable version. It ruined the car- big lag coupled with an auto is not much fun...

Cefiro's don't come standard with a BB turbo, musta been fitted at some stage,
Here's a good article on the XR6T
http://autospeed.drive.com.au/cms/A_1613/article.html

[dangerous]

Yeah baby that bike is a Kawa Z1TC Kawa in the 80's built the GPZ750zx turbo (see Death's profile) which was the fastest mother of all the turbos with Honda's CX650 right behind it, as with the suzuki XN they were injected the Yamaha XJ650 was the only other carbed turbo from the japs.

Z1tc (Z1000)
http://www.turbomotorcycles.org/Images/Bike_s_z1rtc.jpg

ZX750 (GPZ750)
http://www.turbomotorcycles.org/Imag...e_s_gpz750.jpg

XN85 (GS650)
http://www.turbomotorcycles.org/Images/Bike_s_xn85.jpg

XJ650 (XJ650)
http://www.turbomotorcycles.org/Images/Bike_s_xj650.jpg

CX650tc (also as a CX500tc)
http://www.turbomotorcycles.org/Images/Bike_s_cx650.jpg

[HDTboy]

Eww, yuck, carbys mixed with turbos

[dangerous]

for those that give a shit.........

http://www.z-power.co.uk/Images/Z1RTC.jpg

1978/1979 Z1-R TC
The relative poor sales of the standard Z1-R prompted Kawasaki America to team up with the AMERICAN TURBO-PAK Company to produce the Z1-R TURBO. Basically a standard bike with a turbo kit bolted on. No warranty was offered and a few hundred were sold in 1978 in the original silver blue colour. In 1979 a couple of hundred more were produced but this time the bike was painted in black with red, yellow and orange stripes. Very tacky and very seventies. Power output was quoted at anything between 100 and 145 bhp, depending on how much boost the rider dialed in. 160mph was available, on a bike which struggled handling the standard engine output. Performance was exciting, for all the wrong reasons!

[DEATH_INC.]

Jeez so much to cover....
Ball bearing turbo's don't reduce lag that much,it's the sizing that really matters.A normal turbo's shaft floats in oil,not much drag there.....
Anti lag is done by shifting the firing of usually one or two cylinders so they fire with the exhaust valve open , burning the fuel in the exhaust so the turbo thinks it's a jet engine(not really ,but it's the easiest way to explain it...)the other anti lag is yer normal blow off valve,crude but they help....
Turbo's are reliable nowadays,just look how many high k skylines etc are still running sweet.(btw the cefiro and skyline turbo's ARE ballbearing/ceramic turbos)
Lag isn't too bad with most stock setups,but I think what you're talking about is actual spool up rpm,not lag,they are different.
Turbo's do normally make power/torque at lower rpm,the old gpz for example made it's peak (hp)at 9000 i think where the n/a version made it at 11 or so....and the turbo made good useable power from about 3500rpm,where the n/a didn't really get going till about 6 or 7000.
Fuel consumption depends on use,mine will do 200k on a tank if I putt around,but I've also sucked it dry from full in about 100 (from south auck to halfway to wellsford!)
Turbo's aren't on everthing because of added costs in manufacturing,as I had it explained to me, if you build a 200hp engine you have to build all the components to handle 200hp for at least the warranty mileage,so it's often just easier to make it bigger(busa and zx 12 for example)as it will end up just as big and heavy anyway....(this is from a factory veiwpoint anyway...)
As pointed out ,a turbo is much more efficient than a charger,80% effiency as compared to about 50%,but the screw compressors blow all this out of the water with about 90% efficency,dunno why these aren't real popular....
HP...My 20 year old turbo with a measly 8 valves and 810cc runs over 200hp,pretty much what they're getting outta the thou's now,but I'm doing it under 10000rpm.
Anything I've missed?

[TonyB]

Lag isn't too bad with most stock setups,but I think what you're talking about is actual spool up rpm,not lag,they are different.
Turbo's do normally make power/torque at lower rpm,the old gpz for example made it's peak (hp)at 9000 i think where the n/a version made it at 11 or so....and the turbo made good useable power from about 3500rpm,where the n/a didn't really get going till about 6 or 7000.

At last, someone who understands me... I thought I was all alone in the world

[Kickaha]

for those that give a shit.........

http://www.z-power.co.uk/Images/Z1RTC.jpg

1978/1979 Z1-R TC

And if a certain Mr Cotton stops dicking about we'll see one out on Pre82 racing this season