Jump to content
SAU Community

Recommended Posts

Oh also what was your rim and tyre size?

If anyone is interested this is how I convert, I'll assume the nismo is 4.4

KM/H x (1000/60)

This gives your speed in meters per minute.

pi x Diameter (in metres)

This will give you the cirucumference of your wheel in metres.

Speed / Circumference

This gives how many rpm of wheel per minute.

Then divide by diff ratio if in 4th.

Edited by Rolls
  • Replies 101
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Posted Images

Would 18s make it better or worse? Sorry full noob at this shit

I just re did it with 240x40x18 and it is 3955 vs 4010rpm for 110kph

Use these websites

http://www.rkm.com.au/calculators/calculator-circle-sphere.html

another calc

RPM = (diff ratio * (mph * 88)) / (tire circumfrance in inches / 12) * transmission 4th ratio

Edited by Rolls

Just measured on my boost controller and powerfc rpm. Got 3410rpm and 3439rpm hitting 18psi in 4th. Dunno how accurate that is tho lol

Pretty damn accurate I'd say as it is using the CAS and it is low rpm (at high rpm the CAS signal can get inccurate in some cars).

Could you try 2nd gear just out of curiosity? as that is what I think most people are interested in.

Edited by Rolls

Pretty damn accurate I'd say as it is using the CAS and it is low rpm (at high rpm the CAS signal can get inccurate in some cars).

Could you try 2nd gear just out of curiosity? as that is what I think most people are interested in.

Yea I'll give it a squirt tomorrow night haha

If its making that much boost in fourth its not really going to be a whole lot different in second. If anything it wont make full boost as the motor wont have the same ammount of load on it. Its always harder to get full boost in the lower gears.

I would be pretty happy with that sort of response. I know the T78 on our car makes full boost (22-23psi) by about 4500rpm and i built an R32 GTR a few years back that made about 5 psi of boost with a T78 at 2500rpm, full boost (again 22-23psi) by no later than 4000rpm. It was a pretty insane GTR to be honest and a bit of a freak engine.

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

    • So, now all you need to do is connect the 2 or 3x 12v feeds into the unit to permanent 12v, ACC 12V and IGN 12V that you can find in the spot behind the stereo, and the earth, and then it will switch on with the car.
    • Yes then it will turn on but I want the car features to work  
    • My thought is if you were just moving it forward and the upstream geometry remained the same, then no difference at all. But because the current one has the filter direct into the AFM inlet, you effectively have the best chance of a completely symmetric air flow profile upstream, and in, the AFM, whilst the aftermarket inlet thingo has a (small, to be sure) bend between the filter and the AFM. That would bias the flow to the outside of the bend (downstream of the bend) which might well reduce the size of the signal seen by the AFM, for the same total flow rate. Having said that: If you're proposing to make your inlet look like a hybrid of your existing one and the aftermarket one, such that there is no bend where the filter is clamped on... then I say it will be just fine. If there is going to be such a bend, then, if you can align the insertion of the AFM blade such that it is at right angles to the plane of the bend, then there is a better than even chance that the centreline velocity where the blade is will remain more or less the same, and the velocity will just be a little faster to the outside of that, and just a little slower to the inside. **This is not professional investment advice and you should consult a suitably qualified ouija board, tea leaves or the intestines of a goat for more accurate prognostication.
    • Hi Tao, Thanks for your reply.  It's been a while and I managed to get the valve stem seals replaced with the head on the car.  Unfortunately this didn't solve my issue, the car still smokes a lot after idling (to be honest during idle you can see a bit of blue smoke from the exhaust), same after deceleration. I will try disconnecting the valve cover breathers, do I leave the PCV valve in? By engine oil drain pipe, do you mean the turbo oil drain?
    • What about if you just give it direct 12v and earth?
×
×
  • Create New...