Jump to content
SAU Community

Recommended Posts

Seriously? This cannot be true. Think about it.

This really baffles me as well, but that's how it is, even when I bought the car - stock turbo, 12psi etc, it would do 100km/h in 5th at 3000rpms. Only now different story. And manual yes, Manuel Kasko, no.

Ok let's see if I can explain this good enough, for the sack of this discussion we will use 4th gear cause it is 1:1 ratio and we will assume it is a 4.11:1 diff ratio

So the crank turns 4.11 times which in turn turns the gearbox input shaft 4.11 times which tunes the output shaft 4.11 times which turns the diff input shaft 4.11 time then the diff reduces it at a ratio of 4.11:1 which turns the wheel 1 time, this NEVER changes unless you change a ratio in the drive line and is the same for every gear just with different ratios inside the gearbox applied

So revs v speed in any given gear will never change no matter how much power you throw at it

Ok let's see if I can explain this good enough, for the sack of this discussion we will use 4th gear cause it is 1:1 ratio and we will assume it is a 4.11:1 diff ratio

So the crank turns 4.11 times which in turn turns the gearbox input shaft 4.11 times which tunes the output shaft 4.11 times which turns the diff input shaft 4.11 time then the diff reduces it at a ratio of 4.11:1 which turns the wheel 1 time, this NEVER changes unless you change a ratio in the drive line and is the same for every gear just with different ratios inside the gearbox applied

So revs v speed in any given gear will never change no matter how much power you throw at it

Any of you Sydney lads welcome to go for a spin in my 34 on a weekend - we will do 5th gear at 2600rpms - seeing is believing............

Do Ron Ron, just so that I understand this properly: your car was running the stock ecu prior and doing 3000rpm @ 100km/h, then you changed to PFC and got it tuned and are now seeing 2600rpm @ 100km/h.

Is this correct?

Nistune I believe, the ONLY way the revs v speed can change is if you did the test in one gear then later did it in a different gear and some how forgot what gear you did said test in, diff won't change revs v speed nor will tyres as the speed sensor is on the output shaft of the gearbox, I also think the signal goes speed sensor - speedo - computer but could maybe incorrect on that one :)

Tyres diff all same, stock ecu and nistune I was doing 100km/h in 5th at 3000rpms, PFC now I'm doing 2600rpms -normal motorway cruising. And no gay 22" rims, running 18" RAYs wheels

Edited by rondofj
  • Like 1

stock ecu and nistune I was doing 100km/h in 5th at 3000rpms, PFC now I'm doing 2600rpms

He's answered it already. Stock ECU said 3k, as did the Nistune (coz its the same fking ecu). Now the PFC says 2600.

The PFC is reading the sensor voltage that little bit off and sending the wrong reading to the cluster.

WOW

SUCH DIFFICULT

MANY THINK

MUCH SOLVED

Maybe GTScot is right, I always have a funny feeling now that its a bit harder to reach 7000+rpms now cos the car is already going too fast etc, as compared to before. Maybe the tacho reading is off. Maybe its doing 7400rpms already and displaying as 7000 or say I have reached 7000 already when it is showing 6600.

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

    • Ah. OK. I take it back. I hadn't looked closely at the R33/4 arms and presumed that GKTech did as GKTech do everywhere else, which is to use sphericals there. The poly bushings are made to be 100% interchangeable, should use the standard bolt just fine. Every other bush in every other place in pretty much every other car, does.
    • @silviaz Ok cool, so much easier with a video. I can see why this video would be confusing for new players.   It is obvious that this entire bonnet is going to be resprayed, have a look in the background around 2:05, you can see a bunch of bare metal on the left side of the bonnet.  It's not an issue for the primer being laid down on the non-prepped clear on the bonnet. It will be sanded off at a later stage.  This might not be obvious to new players, but working on bare metal and factory paint in this instance, the factory paint is like a mountain and the bare metal is a huge valley. The bonnet needs to be levelled flat before it receives it's final stage of colour and clear coat. During this levelling process, the primer that is landing on the clear that you are worried about will be removed.  Also, this guy is out of control. Zero PPE while spraying, maybe he is a good example overall about what not to do lol.
    • Ok I FINALLY found a video lol. This took way longer than it should have as I could have sworn I saw multiple videos like this. I kept finding the completely opposite (the correct way of doing this). I wouldn't be surprised if I f**ked this up somehow.  I just realised where I've been getting confused and even with other things I work on. I haven't been doing things the regular way instead I'm going a roundabout way of doing things, like putting epoxy primer first then filler for example instead of putting just filler then primer on top of that, then wondering what happens if I get that primer on the clear coat that I haven't sanded yet. This was a bit of an epiphany 😂  But anyways, here this video. Time stamp, 2:56, some of the primer lands on the paint unscuffed above. You can see from the reflection it looks shiny.  
    • It does, this part circled in red. I assume the OEM bolt might not work well with the poly bushing because the dimensions may be different?
    • The J arm doesn't have bushes either. Assuming that by "J arm" you mean the part of the upright that runs down from the upper arm's outer bushes to the top of the hub. That has a kingpin style bearing in it. If you meant the lower control arm, it has 1 bush, at its inner end. If you have PU in there, that is superior to Nismo rubber. If you meant the caster/tension rod - it has 1x bush at the front end, and again PU is superior to Nismo rubber. But as I said above, I would definitely get the GKTech arms for that, as sphericals slay all other options there.
×
×
  • Create New...