J20A and the SX4 WRC car

[TheOtherLeft]

Gotta love this:

SX4
ENGINE Type Turbocharged, water-cooled, developed form the J20engine, in-line 4, DOHC, 16-valve
Cylinder capacity 1,997cm3
Maximum power 235kW(320bhp)/4,000rpm-4,500rpm
Maximum torque 590N-m(60kg-m)/3,500rpm

Just a wee bit more power then the 91kW GV's.

Now how can I get a turbo in mine (plus a few other mods)? ;-p

[nicbeer]

cant wait till if and when they bring this out onto the track.

going by the way the FIA is going it may never get out there.

But awesome power anyway out of it.

Nic

[Guy]

Gotta love this:

SX4
ENGINE Type Turbocharged, water-cooled, developed form the J20engine, in-line 4, DOHC, 16-valve
Cylinder capacity 1,997cm3
Maximum power 235kW(320bhp)/4,000rpm-4,500rpm
Maximum torque 590N-m(60kg-m)/3,500rpm

Just a wee bit more power then the 91kW GV's.

Now how can I get a turbo in mine (plus a few other mods)? ;-p

that is remarkably low rev'f for that much torque from a motor displacing just 2 liters.

[Highway-Star]

that is remarkably low rev'f for that much torque from a motor displacing just 2 liters.

The G13B reaches peak torque at the same, 3500rpm, but this beast has over 5 times the torque! . Sierra gearing would love this engine, OK who's game? .

Are you sure those numbers are correct? I meen, the 4.1L diesel engine I want to put in Dads Lux doesn't produce that much torque! Even 390Nm would be awesome for a small car like the SX4.

[bazooked]

so wats it worth?

[nicbeer]

highway star.

yep those stats are correct. its amazing what u can do with technology and forced induction. the 4.1 u are looking at is prob still 70s tech.

bazooked - going by recent cars, i'd guess 300k for whole car?

Nic

[TheOtherLeft]

that is remarkably low rev'f for that much torque from a motor displacing just 2 liters.

The G13B reaches peak torque at the same, 3500rpm, but this beast has over 5 times the torque! . Sierra gearing would love this engine, OK who's game? .

Are you sure those numbers are correct? I meen, the 4.1L diesel engine I want to put in Dads Lux doesn't produce that much torque! Even 390Nm would be awesome for a small car like the SX4.

I copied and pasted them directly from the SX4 WRC website. So unless they're telling porkies to scare off the competition...

[fordy1]

my stock vitara 2L had 97kw.

[Highway-Star]

highway star.

yep those stats are correct. its amazing what u can do with technology and forced induction. the 4.1 u are looking at is prob still 70s tech.

bazooked - going by recent cars, i'd guess 300k for whole car?

Nic

OK, fair enough. Forced induction can be usefull . It just makes me wonder if you can do that with 2L of engine, just imagine 6 or 7 litres, . I need to get a fix and go to willowbank again.

Meh the 4.1 is a 15B out of a 2000 coaster bus, but yeah rather primitive (mech injection, not forced, pushrod though 16 valve).

[Gwagensteve]

And that's through an inlet restrictor.

I;m shooting from the cuff here, I think wrc cars use 32 or 36mm restrictors. This limits total power to 235kw, and is the most effective way of doing this. However, it does not limit torque to anywhere near the same extent.

As these motors can't be built for more power (due to the restrictor) the objectove is lots of torque over the widest possible range. Toyota at one stage claimed 700nm from their celicas. (may have been the same year tey were cheating though with a "variable orifice" inlet restrictor

Bear in mind, the current STi WRX makes 392 nm with factory reliability, worldwide emissions standards and drive by noise. Evo X's are into the 400's I recall.

6 or 7 boosted litres? Bugatti Veyron - over 1000hp..... and still worldwide emissions and noise.

Steve.

[GRPABT1]

I would imagine that motor would have a far whack of boost up it's date to make that kind of power and most likely not anywhere near emissions friendly. I think there is buckleys chance of a road going model with the same power figures.

[mud4b]

I would imagine that motor would have a far whack of boost up it's date to make that kind of power and most likely not anywhere near emissions friendly. I think there is buckleys chance of a road going model with the same power figures.

more like buckleys chance of a turbo sx4 in aus.

[Gwagensteve]

I would imagine that motor would have a far whack of boost up it's date to make that kind of power and most likely not anywhere near emissions friendly. I think there is buckleys chance of a road going model with the same power figures.

Absolutely not.... and that's the point. Rally motors are built just for that and are totally unsuited to road use. Boost will be fairly low (<20 psi) but airflow and timing/fuel control are far more sophisticated than road cars can afford - were talking $70K of engine management.

(Although in itself, 235 kw from 2L is easy - JDM STi's do that from 2.0l - with 420nm of torque, but 590nm is another league of airflow and management all together, - that's 590nm through rods, crank etc.)

These motors come on so strong that controlling them through road tyres and with road suspension settings would be impossible. WRC bodyshells are often hundreds of % stiffer than stock... track width are wider and the driveline is very sophisticated.

Even my STi is VERY tricky to drive at anywhere near the limit - it's not at all like a "normal" road car - the diffs and power delivery really bite. It doesn't flow - you cant take the same approach at 9/10th as you can at 7 10ths, it will get very scrappy.

Steve.

[GRPABT1]

I would imagine that motor would have a far whack of boost up it's date to make that kind of power and most likely not anywhere near emissions friendly. I think there is buckleys chance of a road going model with the same power figures.

Absolutely not.... and that's the point. Rally motors are built just for that and are totally unsuited to road use. Boost will be fairly low (<20 psi) but airflow and timing/fuel control are far more sophisticated than road cars can afford - were talking $70K of engine management.

(Although in itself, 235 kw from 2L is easy - JDM STi's do that from 2.0l - with 420nm of torque, but 590nm is another league of airflow and management all together, - that's 590nm through rods, crank etc.)

These motors come on so strong that controlling them through road tyres and with road suspension settings would be impossible. WRC bodyshells are often hundreds of % stiffer than stock... track width are wider and the driveline is very sophisticated.

Even my STi is VERY tricky to drive at anywhere near the limit - it's not at all like a "normal" road car - the diffs and power delivery really bite. It doesn't flow - you cant take the same approach at 9/10th as you can at 7 10ths, it will get very scrappy.

Steve.

Bwhahaha! My V8 commodore is quicker than an sti. Try that kinda power/speed with only rear wheel drive! That is when things can get interesting

[Gwagensteve]

I think you have misunderstood me.

Maybe your commodore is quicker than an STi under the right conditions ( no corners ), but low traction cars aren't that hard to drive-they're pretty intuitive. - you just have to work within the traction. If you overdo it, it will start drifting.

4WD cars don't tend to have a very natural handling balance - there is a point where they start to feel weird as they nudge up against their adhesion limit. With the centre diff set to "auto" in my STi once the apex is passed the car will go completely neutral. More throttle makes it corner harder, not oversteer or understeer. This is pretty common for front heavy 4WD cars but is very hard to get used to. To make the quickest progress on a winding road you really have to exploit this and that's a major challenge because it both generates very high cornering loads and forces you to put power in when your mind is telling you the car will let go.

Deploying 690nm in a car like this would be really hard work, especially if it was all in @ 3500rpm with peak power at 4500! - that's a 1000rpm powerband! There's no way a consumer would tolerate that.

Steve.

[Remydog05]

Lets get back to the topic and finish the how bigs ya Competition

Heres a start for ya 8

Hope ya got a big checkbook!

You might struggle to get it Road Legal??

http://www.importperformanceparts.net/i ... uzuki.html

[TheOtherLeft]

Lets get back to the topic and finish the how bigs ya Competition

Heres a start for ya 8

Hope ya got a big checkbook!

You might struggle to get it Road Legal??

http://www.importperformanceparts.net/i ... uzuki.html

What sort of performance increase would you get out of only replacing the head gasket, pistons, rings and bearings with high performance ones?

[GRPABT1]

I think you have misunderstood me.

Maybe your commodore is quicker than an STi under the right conditions ( no corners ), but low traction cars aren't that hard to drive-they're pretty intuitive. - you just have to work within the traction. If you overdo it, it will start drifting.

4WD cars don't tend to have a very natural handling balance - there is a point where they start to feel weird as they nudge up against their adhesion limit. With the centre diff set to "auto" in my STi once the apex is passed the car will go completely neutral. More throttle makes it corner harder, not oversteer or understeer. This is pretty common for front heavy 4WD cars but is very hard to get used to. To make the quickest progress on a winding road you really have to exploit this and that's a major challenge because it both generates very high cornering loads and forces you to put power in when your mind is telling you the car will let go.

Deploying 690nm in a car like this would be really hard work, especially if it was all in @ 3500rpm with peak power at 4500! - that's a 1000rpm powerband! There's no way a consumer would tolerate that.

Steve.

My point was that oversteer can be scarier than grip. But I agree understeer is worse still.

And my commodore is an ex-circuit raceing car so your understeering WRX has more chance on the drag strip

[Guy]

I think you have misunderstood me.

Maybe your commodore is quicker than an STi under the right conditions ( no corners ), but low traction cars aren't that hard to drive-they're pretty intuitive. - you just have to work within the traction. If you overdo it, it will start drifting.

4WD cars don't tend to have a very natural handling balance - there is a point where they start to feel weird as they nudge up against their adhesion limit. With the centre diff set to "auto" in my STi once the apex is passed the car will go completely neutral. More throttle makes it corner harder, not oversteer or understeer. This is pretty common for front heavy 4WD cars but is very hard to get used to. To make the quickest progress on a winding road you really have to exploit this and that's a major challenge because it both generates very high cornering loads and forces you to put power in when your mind is telling you the car will let go.

Deploying 690nm in a car like this would be really hard work, especially if it was all in @ 3500rpm with peak power at 4500! - that's a 1000rpm powerband! There's no way a consumer would tolerate that.

Steve.

My point was that oversteer can be scarier than grip. But I agree understeer is worse still.

And my commodore is an ex-circuit raceing car so your understeering WRX has more chance on the drag strip

So your heavily modded commadore might out hanlde a factory Subi With a motor that has more than twice the capacity

Put the same mods in the the subaru and watch your commadore lumber like the dinosaur it is.


The entire point of what Steve is saying has nothing to do with capacity, it is to do with driveability and what the consumer would accept from a factory vehicle.

[Remydog05]

Dunno how much perfomance but thats a kit you would use to build a turbo motor which is what you were asking about.

[Gwagensteve]

My point was that oversteer can be scarier than grip. But I agree understeer is worse still.

I know where well off topic now, but I do need to respond to this. I'm sorry, your'e off track here. mild understeer is the quickest way though a corner (every race team and every manufacturer knows this)

If you prefer oversteer, that's great. I've owned oversteering cars too, but they're not a very effective way of driving a real road.


to get the thread back on track -

Love_mud - the low revs for peak power are due to the inlet restrictor. The motor just won't be able to flow any more air. I'm willing to bet if it spun ay quicker it would break anyway- the loadings on the engine will be maxed out at these revs with that much torque. from what I have seen, the architecture of J20's is not very well suited to high loads/revs, especially with boost.

Not many people with a road car would be willing to tune an engine that way.

[GRPABT1]

[/quote]

So your heavily modded commadore might out hanlde a factory Subi With a motor that has more than twice the capacity

Put the same mods in the the subaru and watch your commadore lumber like the dinosaur it is.


The entire point of what Steve is saying has nothing to do with capacity, it is to do with driveability and what the consumer would accept from a factory vehicle.[/quote]

My commodore doesn't have a turbo either, give me one if you want to even things up, and it's nearly 20 years old also.

I agree the J20a wouldn't rev anywhere near as freely and say a G13b being a much bigger bore/stroke. What's the gear ratios like? I'd imagine you'd need a really close ratio box with lots of gears to take full advantage of the small torque range.

[robsjimny]

Go the swift 1600

non turbo 160kws 1.6 nice

Think it's a race / rally pack.

http://www.suzukisport-europe.com/sales ... /main.html

Rob

[Gwagensteve]

Everyones forgetting about the intake restrictor WRC cars must run.

The restrictor is BEFORE the turbo. this means that there is an absolute limit on how much air the engine can consume - and it's about 235kw worth. there's no way around this - even a 1000hp motor (unrestricted) would only make 235kw through the wrc restrictor, but might not make any torque at all. Many motorsport categories use inlet restrictors to keep the lid on HP.

The restrictor limits HP but not torque, however, to make very high torque, the engine will be consuming lots of air - close to its total flow - which means that if you are making lots of low end torque, your peak revs will be lower too. This is a happy coincidence as the J20 architecture was never intended to take boost and revs with boost would make it unreliable.

WRC cars run very close ratio gear sets and choose ratios depending on conditions.

Steve.

[cj]

As Steve said, there's only so much that you can put through a 34mm restrictor.

The J20A in stock form although able to handle some boost fine was certainly not given the ideal architecture for high boost. The J23A has a bit better bottom end but you can be sure that the engine in the WRC car is a "touch" different with regards to some internal features that will allow for the boost that they will be running and maintain reliability.

It will be interesting to learn more about what they have done for the WRC cars and in particular to see what they do for the street version that will go on sale to the public.