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

    • Is it alright to top up with just another green coolant?
    • thanks GTSboy. My confusion at the moment is i am trying to locate the ignition, ECU battery power and the ECU negative The closest thing i can find is the for the S15 on Page 8 of the Wiring Specialties web page https://drive.google.com/file/d/0B9F33_M_GgENQnZ6STMxVmVNd1E/view?resourcekey=0-eZ4nNRwRoqa1qvKlWWHm8A I cannot find the same diagram for the R33 RB25DET Series 2 dash plug pin out.... Do you know what the Pins? or know where i can find the same pinout diagram for the RB dash plug? Thanks for the advice on the box... i like a 6 speed so might be on the lookout or the box now.. a topic of discussion for another post...
    • Will have a look at that. I cant see any leaks 
    • Put another overflow bottle (ie, a 1.25 coke bottle or similar) under the overflow hose and see if it is being pushed out there or if it is disappearing into the engine.
    • Staring on a stand is no issue. You just have to wire everything up, give it fuel and cross your fingers that the stand is robust enough. Arranging the inlet plumbing is often the hardest part, without any surrounding structure to hand some of it from. No need for coolant if you only want to run it for <1 minute. As to the gearbox - I think the little Aisin box is a bit stronger than the other small Nissan boxes that went behind SRs, but I wouldn't be too keen to test its limits with the torque of a boosted 25. I don't know if you can retain the box and the tailshaft. The box won't connect to the RB without an adapter of some sort, which is either a plate that will push the engine forward (which is not good for fitting it into the bay's available space) or push the box back, which messes with the box position and tailshaft length - OR - cut and shut work on the bellhousing, which is a long way from "least modification". I'd be buying a new 370Z 6 speed or similar, doing what has to be done to that to make it fit RB (ie, cut and shut bellhousing) and the requisite tailshaft custom/mods.
×
×
  • Create New...