JUBU Emira 500 Power upgrade

[JonFuller]

This is how a rev limiter should work / sound!

 

[silent cilantro]

I was about to post that! They also posted a version with redline at stock 6800

 

[Nova]

Neat. It looks like they dial down the torque output from 6800-7200 so the HP just stays flat at 460.

 

[JonFuller]

Neat. It looks like they dial down the torque output from 6800-7200 so the HP just stays flat at 460.

Shame, it won't be pulling quite as hard in those latter stages. I guess they must have their reasons.

A cynic might think that if the torque stayed flat @ 500ish nm, the HP produced at 7.2k might be a bit too close to the very costly 500hp upgrade.

Or am I just a grumpy old bugger?

 

[Nova]

It really depends.

Mechanical systems often have limits which act more like inflection points, rather than a linear line or a curve. Prior to or even close to the inflection point, the system works nominally and there is only marginal long term wear for each marginal increase in power output. But at or beyond the inflection point, all heck breaks loose and the system is prone to sudden failure.

For example, the valve weight plus the valve spring rate, in addition to the friction in the system, and the oil weight, has a resonant frequency at which point the valve will simply float open rather than close. So, without upgrading some engine internals, there may be such an inflection point that getting beyond 460HP at 7200 RPMS would get too close to, and result in intermittent faults that degrade engine life.

It's really not an issue to have the HP stay flat from 6800 to 7200 RPM, you are still getting 460HP during that range, which is nothing to sneeze at.

 

[motorpool]

I like the 460 option, might check if they can remove the exhaust components as I'm getting a titanium setup with bypass and headers. That would make it more palatable. Or are there other places in US that will / would offer similar

 

[JonFuller]

It really depends.

Mechanical systems often have limits which act more like inflection points, rather than a linear line or a curve. Prior to or even close to the inflection point, the system works nominally and there is only marginal long term wear for each marginal increase in power output. But at or beyond the inflection point, all heck breaks loose and the system is prone to sudden failure.

For example, the valve weight plus the valve spring rate, in addition to the friction in the system, and the oil weight, has a resonant frequency at which point the valve will simply float open rather than close. So, without upgrading some engine internals, there may be such an inflection point that getting beyond 460HP at 7200 RPMS would get too close to, and result in intermittent faults that degrade engine life.

It's really not an issue to have the HP stay flat from 6800 to 7200 RPM, you are still getting 460HP during that range, which is nothing to sneeze at.

460 all the way, yes, but the pull will be declining, as the twisting force actually getting to the wheels is reducing with every extra rpm.
It is what is I guess.

I see that if you have the wonga, they will now build you a 600hp.
But that must require an altogether stronger gearbox as well.

 

[Speedy Emira]

460 all the way, yes, but the pull will be declining, as the twisting force actually getting the wheels is reducing with every extra rpm.
It is what is I guess.

I see that if you have the wonga, they will now build you a 600hp.
But that must require an altogether stronger gearbox as well.

With 600 you have to fit the carbon vent unit and remove the rear glass..
if you want the ultimate track weapon they can build you a 750 twin turbo engine with a sequential gearbox and paddle shit. Not for me but would be impressive if you had €100k spare.

 

[luciddaydream]

I am no car genius but wouldn't like 500-600 hp just be too much on this little car? Are the tires even wide enough for all that power?

 

[Speedy Emira]

I am no car genius but wouldn't like 500-600 hp just be too much on this little car? Are the tires even wide enough for all that power?

I reckon 500 is probably the sweet spot without going overkill. My RS3 was over 700hp with 245/30/20s but it has AWD to spread the power. 295 tyres RWD should be ok for 500hp on this chassis with cup 2 tyres.
If someone was mad enough and their pockets were deep enough for 600-750hp they could have multiple maps on Syvecs so a fast road map could be made manageable.

 

[luciddaydream]

I reckon 500 is probably the sweet spot without going overkill. My RS3 was over 700hp with 245/30/20s but it has AWD to spread the power. 295 tyres RWD should be ok for 500hp on this chassis with cup 2 tyres.
If someone was mad enough and their pockets were deep enough for 600-750hp they could have multiple maps on Syvecs so a fast road map could be made manageable.

Ok, thanks. Sounds badass..

Hey do you think these power upgrades will improve the 0-60 or is that usually not how it all works?

 

[Time2Fly]

No one wants Chav gun shots! (except for Chavs I guess. ..for the merkins here, a Chav is a bit of a redneck)

Jubu say that the ECU supports automated rev-matching, but I'm not sure how that would work with emira. Surely it would require the gearbox to inform the ecu what gear you're in / going into?

I don't think Emira has any sensors or switches on the gearbox telling the ecu where it's at.

Interesting that it says the ECU auto blips on downshift as well. I wonder how they're doing that.

 

[Speedy Emira]

I see JUBU are now doing a 440 upgrade. https://www.jubu-performance.com/en/shop/part-jubu_emira_440_leistungskit-2493

After comparing it looks like the 430 produces 435hp with an air filter, gpf replacement pipe and the stack software option which I believe is a piggy back unit that sits in between the sensors and ecu.
The 440 however doesn’t state hardware but I’m guessing it’s the same as above but uses their bespoke Syvecs ecu.
For me the 440 kit is better because it states the upgrades will reduce the cost of a 500 upgrade. I’m not convinced in the UK we could fit the manifolds without cats unless there is a way that it could still pass an emissions test with one performance cat. Maybe with Syvecs they could have a program that could be ran just for the test but not with load. Hopefully I will get further info from my tuner next week.
Either way I personally won’t go over 435/440 without having the built option with the upgraded clutch/flywheel option.
I am a big fan of Syvecs having used them twice previously and they have better knock protection than oem.

 

[JonFuller]

I think the cats in the std manifolds are just warm up cats, no sensors either side.
The replacement of the main cat with the 200 cell sport cat should, I think be ok for emissions

 

[Speedy Emira]

Hi Jon, I hope you are correct on this because it makes things much easier. The confusing part is I’ve seen the manifold ones being called cats and the other called a gpf filter. I remember on RS3s the year after mine they fitted a gpf in addition to the cat.

 

[JonFuller]

As I understand it, the manifold cats are set close to the ports, and designed to warm up very quickly on startup so its clean from virtually cold.
Once warm, the main (3rd) cat does it all.

There is no GPF on Emira. Well not the v6 anyway, Dunno about the 4 banger.

 

[JonFuller]

The 440 kit looks good, and potentially 445 with decat pipe.

Looks like they’re listening to customer questions, as all of that relates to what I’ve been asking for.
Maybe similar with a sportcat 200 replacement.
I will go to 460 at some point, 500, cant afford or justify

 

[kitkat]

I think the cats in the std manifolds are just warm up cats, no sensors either side.
The replacement of the main cat with the 200 cell sport cat should, I think be ok for emissions

That’s unfortunately incorrect, both manifold cats have pre and post oxygen sensors — 4 sensors in all.

Left & right bank cats: upstream and down stream sensors and responsible for most of the emissions as they are platinum, palladium and rhodium from the emissions documentation.

Third cat: zero sensors and responsible for less cleanup, it’s a cat without platinum.

You are correct that there is no GPF however.

The service manual outlines all of this.

Some of the exhaust aftermarket is offering a race header design that deletes the primary cats. These kits sell with or without a low cell count cat that replaces the third cat and comes with taps for all four sensors and cables to extend the location of the sensors to the singular cat.

 

[JonFuller]

Ah, ok, thanks for the info 👍

 

[Speedy Emira]

That’s unfortunately incorrect, both manifold cats have pre and post oxygen sensors — 4 sensors in all.

Left & right bank cats: upstream and down stream sensors and responsible for most of the emissions as they are platinum, palladium and rhodium from the emissions documentation.

Third cat: zero sensors and responsible for less cleanup, it’s a cat without platinum.

You are correct that there is no GPF however.

The service manual outlines all of this.

Some of the exhaust aftermarket is offering a race header design that deletes the primary cats. These kits sell with or without a low cell count cat that replaces the third cat and comes with taps for all four sensors and cables to extend the location of the sensors to the singular cat.

Thanks for the info. These cars are so new it’s hard to know the facts and at least we have a forum we can pick each other’s brains and learn from each other.
I’m interested to hear from someone with a sports car and the headers to see if it can pass the emissions test.