JUBU and other topics, a combo thread

[JonFuller]

As I have stated it’s my feeling, it’s that simple. Others have felt that the stock redline cuts off sooner that what’s expected. Maybe the digital screen which yes could be wrong…but maybe not, no one knows.

I had a problem with the car when I test drove it. I didn’t like the hard cut off and it looked like it cut off at 6600 TO ME. So I did something about it. That something was JUBU tune with the 7200 redline. Once again to me it felt like I gained 600 rpms not 400.

I’m sharing my experience yet you want to dissected like it’s not correct. Opinions and how something feels is unique.

For example the Evora 7k redline vs the Emira “6,800” is 200 rpm’s so you can compare these feelings. If we lined them all up drove each back to back I think most would agree that my 7200 feels more than the 600 gained over stock Emira. Again maybe not maybe it’s the dash, but if it was the dash would my new ECU effect that bc I didn’t change any other “sensors” other than ECU.

Everyone will argue their point on here. I really don’t care to make my point. Sharing my experience as others might be feeling the same thing. But yes I’m on the hated brand of JUBU so everything must be argued tooth and nail to make a point lol.

I hate the hard, abrupt cut too.
I've found it does cut at 6800, but if you keep your foot 'in', it drops to, and holds at 6600. I think the harsh cut, and subsequent drop of 200 rpm before it holds at 6600 is what makes it feel so very abrupt. The nice soft 'stammer' , hovering at 7200 with the Syvecs ecu is a breath of fresh air after that stock ecu experience.

Just my humble opinion.

 

[hellasf1]

I hate the hard, abrupt cut too.
I've found it does cut at 6800, but if you keep your foot 'in', it drops to, and holds at 6600. I think the harsh cut, and subsequent drop of 200 rpm before it holds at 6600 is what makes it feel so very abrupt. The nice soft 'stammer' , hovering at 7200 with the Syvecs ecu is a breath of fresh air after that stock ecu experience.

Just my humble opinion.

Yea you’re probably right.

I remember my dealership telling me this happened bc their car was new, so I was optimistic, come to find out when I got mine it was just a bad feature Lotus decided felt good.

Yes now it’s perfect and how the car should have came.

 

[JonFuller]

I’m not a scientist, but it seems like one way to prove the jubu car changes redline would be to post a photo….

Here you go, 1 photo with stock ecu, one with Syvecs.

So it does indeed show 7000, and not 7200, so apologies to TFS, but there's definitely a change from 6800.

 

[hellasf1]

Here you go, 1 photo with stock ecu, one with Syvecs.

So it does indeed show 7000, and not 7200, but deff a change from 6800.

Yea and as discussed you can take it past that 7k visual redline to 7200. And choose a soft limiter which I have as well.

 

[JonFuller]

Actually, I've only just noticed that the spacing of the numbers changes from the 7k mark onwards (RPM per MM halves).
So taking that into account, if you look carefully, the start of the red ribbon, is actually at about the 7200rpm mark.
The width of the leading white bit of the ribbon must be pretty close to 200rpm's worth in that more bunched up part of the rpm range.

Below 7k, 1000rpm is represented by two divisions, after 7k, that same lengthed two divisions represents 2000rpm.

It's a quirk of the instrument layout.... It's not linear at the top end.

 

[hellasf1]

Actually, I've only just noticed that the spacing changes from the 7k mark (RPM per MM halves).
So if you look carefully, the start of the red ribbon, is actually at about the 7200 mark.
The width of the leading white bit of the ribbon must be pretty close to 200RPM's worth at that more bunched up range.
below 7k, 1000rpm is represented by two divisions, after 7k, that same two divisions represents 2000rpm.

I think your right…we been lookin for the white line but I think that line is gone and it’s actually at 7200 rpm.

So in that case I take it to 7200 than. You just solved the case lol!

 

[hellasf1]

Picture for reference. White line is not under the 7.

 

[JonFuller]

So maybe I'm not a liar.

Funny that all this fuss started just because I noted that it was interesting that the methods of getting extra power were diametrically opposed tween VF and JUBU, ie, JUBU reduce the boost for engine safety/peak torque reasons (to avoid piston failure running with a torque value significantly above 500nm), and VF increase the boost, which must result in far higher torque than the JUBU offering......

"interesting that they'll over-drive the supercharger, when JUBU specifically say that to achieve 460 & above reliably, they under-drive the SC (increasing SC pulley size to reduce boost), otherwise piston failure can be an issue on an otherwise std motor.
Just sayin."

Ho Hum.

 

[sbproducer]

Picture for reference. White line is not under the 7.
View attachment 71073

But when does the meter start flashing for you to shift?

 

[hellasf1]

So maybe I'm not a liar.

Funny that all this fuss started just because I noted that it was interesting that the methods of getting extra power were diametrically opposed tween VF and JUBU, ie, JUBU reduce the boost for engine safety/peak torque reasons (to avoid piston failure above 500nm), and VF increase the boost......

"interesting that they'll over-drive the supercharger, when JUBU specifically say that to achieve 460 & above reliably, they under-drive the SC (increasing SC pulley size to reduce boost), otherwise piston failure can be an issue on an otherwise std motor.
Just sayin."

Ho Hum.

Yeah not a liar at all. But everyone has a different take on how much power this engine can take.

From my understanding Lotus put a Camry V6 and put a supercharger on it, tuned it and that’s it. The internals weren’t reinforced or strengthened. So that’s where I have a hard time believing a stock Camry engine can handle 600 hp and high boost without modification.

So based on my research and my hypothesis I decided to go JUBU and believe them in this manner.

Not everyone that has a problem comes on forums and discusses it and on the other side not everyone who has no issues is on the forums discussing it.

Maybe if we get someone from Toyota who knows this engine inside out and truly knows it’s limitation and what’s “safe” power levels for this engine.

 

[hellasf1]

But when does the meter start flashing for you to shift?

I think right at the redline. I will have to look closely next time and report back.

 

[NorCalEmira]

Yeah not a liar at all. But everyone has a different take on how much power this engine can take.

From my understanding Lotus put a Camry V6 and put a supercharger on it, tuned it and that’s it. The internals weren’t reinforced or strengthened. So that’s where I have a hard time believing a stock Camry engine can handle 600 hp and high boost without modification.

So based on my research and my hypothesis I decided to go JUBU and believe them in this manner.

Not everyone that has a problem comes on forums and discusses it and on the other side not everyone who has no issues is on the forums discussing it.

Maybe if we get someone from Toyota who knows this engine inside out and truly knows it’s limitation and what’s “safe” power levels for this engine.

There's no definitive answer on how much boost, torque or horsepower the 2GR engine can withstand but even the Jubu built short block uses the factory forged crank. They replace the factory forged rods and cast pistons with higher strength forged components in both areas.

You won't find another factory turbocharged or supercharged car with cast pistons, they always choose stronger forged pistons in boosted applications when designing from the ground up. Our cast pistons are suboptimal and the achilles heal for us but it's still difficult to say how much is too much as many have added aftermarket superchargers to a variety of engines with cast pistons.

We also have empirical evidence of people running substantially higher power levels than Jubu advises that can be found online and we can look at what has been done on the Evora which shares the same powertrain. At the end of the day, we all have to decide what we're comfortable with. The farther we push the envelope, the greater the risk to the engine and components downstream but that's always the case when modifying cars.