Jump to content
SAU Community

Recommended Posts

Kasko you need to be aware that the feeling you're after doesn't last, you do get used to it. Like you keep referring to your stock turbo giving the feeling you're after, yet if I was to go for a ride in a stock GTT I bet it would feel like I was in a Getz.

Probably the reason why modding is so ridiculously addictive.

My stock r33 felt like a super car web I got out of an auto Mazda 323 into it haha

Cheers for all the info

Heres my torque graph. Never noses over. Keeps climbing. Maybe we should all run small wastegates and let the boost climb the more the rpm increases.

What kind of pussy are you? just weld it shut like all the cool kids whistling.gif

What kind of pussy are you? Just get a eBay split dump pipe like all the cool kids.

P.S. let's be careful not to confuse rear wheel torque with engine torque...

That's... Exactly what I said. Lol.

Most likely because of my lack of VCT, my G3 doesn't build torque very quickly. It still creates a lot of torque, but it's not a steep curve. My mates TD05 actually has a steeper torque curve, despite being more responsive. It makes less peak torque and less peak power, but the shape of his curve gives his car more of the rush.

Kasko, you need to be aware that the feeling you're after doesn't last, you do get used to it. Like you keep referring to your stock turbo giving the feeling you're after, yet if I was to go for a ride in a stock GTT I bet it would feel like I was in a Getz.

Haha ok but not having VCT would make it more of a rush because below 4500rpm you would have less power but the same top end as the ECU turns it off around then anyway.

Heres my torque graph. Never noses over. Keeps climbing. Maybe we should all run small wastegates and let the boost climb the more the rpm increases.

Seriously though thats what I have always thought it would be good to have boost gradually climbing to stop the torque dropping off.

Obvious problem is though on a really cold night etc because the wastegate is maxxed out the boost would climb higher and could get you into trouble. I suppose if you had the tune allow for this it could be ok.

No it didn't... Power is directly related to torque. If it made 530Nm at 4200RPM it is making 233kw at 4200RPM.

Can you explain????? My car made 625Nm of Torque but my auto could only handle 212 rwkw

No worries, DVS JEZ on this forum tuned it - he has the dyno data for it also :action-smiley-069:

As has been discussed many times on this forum; "Torque" generally can not be compared between Dynos as they measure tractive effort and the torque reading depends on the calibration of the Dyno. Hence saying your 207rwkw SR20 has the torque of a 300kw RB25 is not correct. As you can see from Jez's graph on the previous page, his 300rwkw produces "700Nm" of torque on his Dyno.

A reliable way to calculate actual wheel torque is to use the Power and RPM readings:

T = (Px60x1000)/(RPMx2xPi)

Seriously though thats what I have always thought it would be good to have boost gradually climbing to stop the torque dropping off.

Obvious problem is though on a really cold night etc because the wastegate is maxxed out the boost would climb higher and could get you into trouble. I suppose if you had the tune allow for this it could be ok.

See the way I see it if you are running the max airflow a turbo can provide at redline, then that same airflow at x psi will be x+y psi in the midrange, hence you should run more boost in the midrange to make the most of the turbo.

Like if you look at the compressor map then the same airflow at redline at 20psi is 25psi in the midrange. So if you can get away with running more boost at redline, you should increase the midrange boost to make the most of it.

Which is why I think turbos should be set based on airflow not psi. Though if you do it this way you are always going to have a massive midrange spike and have torque fall off by redline which just doesn't feel as good for some people, though for drifting etc it is perfect.

Thoughts people?

Can you explain????? My car made 625Nm of Torque but my auto could only handle 212 rwkw

625nm of tractive torque, not torque at the engine, dynos don't measure engine torque they measure tractive effort.

if you are making 530nM at 4200rpm then you are ALWAYS make 233 kw at 4200rpm, it isn't possible to be anything else.

Edited by Rolls

Tomorrow night. A customers tyres got slashed at his place so ive finally got some dyno time to my self. Will post in kando thread

Must have been my exhaust that rowelled everyone up lol

FKN NOISY ASS CAR *slashes wrong dudes tyres*

Heres my torque graph. Never noses over. Keeps climbing. Maybe we should all run small wastegates and let the boost climb the more the rpm increases.

The reason behind that is because your car is running on E85, High mount exhaust manifold and external gate.

Run pump 98, internally gated with stock manifold. That power and torque figure will drop significantly after 6000RPM. which is like:

2012-01-301934201.jpg

There are lot more to think about when building a turbo made to perform on Pump 98 and internally gated. A turbo that can deliver performance internally gated on pump 98, has no issues cracking the extra KWs on external gate with E85.

See the way I see it if you are running the max airflow a turbo can provide at redline, then that same airflow at x psi will be x+y psi in the midrange, hence you should run more boost in the midrange to make the most of the turbo.

Like if you look at the compressor map then the same airflow at redline at 20psi is 25psi in the midrange. So if you can get away with running more boost at redline, you should increase the midrange boost to make the most of it.

Which is why I think turbos should be set based on airflow not psi. Though if you do it this way you are always going to have a massive midrange spike and have torque fall off by redline which just doesn't feel as good for some people, though for drifting etc it is perfect.

Thoughts people?

Yeah if your car can put the extra mid range torque to the ground then sure. And that is specifically to do with a turbocharger.

In my previous setup it would spin the tyres when it hit boost in the mid range and then torque would fall off higher in the rev range so when you finally got traction it had lost a lot of torque.

I am more talking from a traction point of view. As speed increases, the greater torque you can put to the ground without wheelspin. Therefore ideally for maximum acceleration given a set amount of traction you would have torque increase with rpm.

I am more talking from a traction point of view. As speed increases, the greater torque you can put to the ground without wheelspin. Therefore ideally for maximum acceleration given a set amount of traction you would have torque increase with rpm.

From a traction perspective totally agree, in fact you see a lot of factory cars do tricky things to do exactly this, a sharp rise in torque almost always induces wheelspin.

Look at the 3L TT inline 6 BMW engines, all sorts of trickery to keep the torque flatish and not have massive peaks like our cars.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Well, after the full circus this week (new gearbag, 14 psi actuator on, injectors and AFM upgraded, and.....turbo repair) the diagnosis on the wastegate is in. It was broken. It was broken in a really strange way. The weld that holds the lever arm onto the wastegate flapper shaft broke. Broke completely, but broke in such a way that it could go back together in the "correct" position, or it could rearrange itself somewhere else along the fracture plane and sit with the flapper not parallel to the lever. So, who knows how and when exactly what happened? No-one will ever know. Was it broken like this the first time it spat the circlip and wedged itself deep into the dump? Or was it only broken when I tried to pry it back into place? (I didn't try that hard, but who knows?). Or did it break first? Or did it break between the first and second event of wierdness? Meh. It doesn't matter now. It is welded back together. And it is now held closed by a 14 psi actuator, so...the car has been tuned with the supporting mods (and the order of operations there is that the supporting mods and dyno needed to be able to be done first before adding boost, because it was pinging on <<14 psi with the new turbo with only a 6 psi actuator). And then tuned up a bit, and with the boost controller turned off throughout that process. So it was only running WG pressure and so only hit about 15-16 psi. The turbo is still ever so slightly lazier than might be preferred - like it is still a bit on the big side for the engine. I haven't tested it on the road properly in any way - just driven it around in traffic for a half hour or so. But it is like chalk and cheese compared to what it was. Between dyno numbers and driving feedback: It makes 100 kW at 3k rpm, which is OK, could be better. That's stock 2JZ territory, or RB20 with G series 550. It actually starts building boost from 2k, which is certainly better than it did recently (with all the WG flapper bullshit). Although it's hard to remember what it was like prior to all that - it certainly seems much, much better. And that makes sense, given the WG was probably starting to blow open at anything above about 3 psi anyway (with the 6 psi actuator). It doesn't really get to "full boost" (say 16 psi) until >>4k rpm. I am hopeful that this is a feature of the lack of boost controller keeping boost pressure off the actuator, because it was turned off for the dyno and off for the drives afterward. There's more to be found here, I'm sure. It made 230 rwkW at not a lot more than 6k and held it to over 7k, so there seems to be plenty of potential to get it up to 250-260rwkW with 18 psi or so, which would be a decent effort, considering the stock sized turbo inlet pipework and AFM, and the return flow cooler. According to Tao, those things should definitely put a bit of a limit on it by that sort of number. I must stress that I have not opened the throttle 100% on the road yet - well, at least not 100% and allowed it to wind all the way up. It'll have to wait until some reasonable opportunity. I'm quite looking forward to that - it feels massively better than it has in a loooong time. It's back to its old self, plus about 20% extra powers over the best it ever did before. I'm going to get the boost controller set up to maximise spool and settle at no more than ~17 psi (for now) and then go back on the dyno to see what we can squeeze out of it. There is other interesting news too. I put together a replacement tube to fit the R35 AFM in the stock location. This is the first time the tuner has worked with one, because anyone else he has tuned for has gone from Z32 territory to aftermarket ECU. No-one has ever wanted to stay Nistuned and do what I've done. Anyway, his feedback is that the R35 AFM is super super super responsive. Tiny little changes in throttle position or load turn up immediately as a cell change on the maps. Way, way more responsive than any of the old skool AFMs. Makes it quite diffifult to tune as you have to stay right on top of that so you don't wander off the cell you wanted to tune. But it certainly seems to help with real world throttle response. That's hard to separate from all the other things that changed, but the "pedal feel" is certainly crisp.
    • I'm a bit confused by this post, so I'll address the bit I understand lol.  Use an air compressor and blow away the guide coat sanding residue. All the better if you have a moisture trap for your compressor. You'd want to do this a few times as you sand the area, you wouldn't for example sand the entire area till you think its perfect and then 'confirm' that is it by blowing away the guide coat residue.  Sand the area, blow away the guide coat residue, inspect the panel, back to sanding... rinse and repeat. 
    • The detail level is about right for the money they charge for the full kit... AU$21.00 each issue, 110 issues for a total of $2,300 (I mentioned $2.2K in the first post when the exchange rate was better). $20/week is doable... 😐
    • If planning on joining us for the day(s) please indicate by filling in this form. https://forms.gle/Ma8Nn4DzYVA8uDHg7
    • You put the driver's seat on the wrong side! Incredible detail on all of this. It looks like you could learn a lot about the car just from assembling the kit.
×
×
  • Create New...