Jump to content
SAU Community

Recommended Posts

And this is probably close to as responsive as possible for the power made on a R34 GTT factory RB25det Neo, running newly developed ATR43SAT BB internally gated bolton turbo on P98 fuel. 317rwkws @21psi, 20psi @ 3550RPM.

power.JPG

boost.JPG

  • 2 weeks later...
  • 2 months later...

Why do most of the dyno grahs show power fall over at the top end?

Because most people run along the edge of the compressor efficiency curve. This means they get max turbo airflow in the midrange and also in the top end. If you get similar airflow at 5000rpm as you do at 8000rpm then this means reduced torque as you are sharing the same air over more combustion events, reduced torque means reduced power.

Most factory turbo cars don't smash the boost in the midrange or max the turbo out, hence they can hold flat torque to redline. If they didn't then you'd see the typical huge midrange torque and dropping off at redline.

And this is probably close to as responsive as possible for the power made on a R34 GTT factory RB25det Neo, running newly developed ATR43SAT BB internally gated bolton turbo on P98 fuel. 317rwkws @21psi, 20psi @ 3550RPM.

power.JPG

boost.JPG

Tao, what is the expected results on an RB25DET? Considering swapping my turbo out for a smaller one for less lag.

If I drop the exhaust or run external gate, top end torque curve would be more flat. For a good turbo configuration on a good internally gated setup. On pump fuel, The torque curve is usually an umbralla shape.

ill be running the non bb version of the 43sat iwg on my car, hoping to tune it next weekend yet that will depend if a part i ordered tonight gets here in time, if it doesnt then whatever day it gets here ill throw it on my dyno and see how it goes. stock rb25, 3"tbe, fmic, so that should give you a better idea if you can wait a week or two

  • Like 1

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

    • Just a thought, was that car and auto at any point of its life? If so, maybe whoever bridged the inhibitor switch/circuit did a not so good job.
    • Wife wanted basket things in the wardrobe in our temporary house. Thought about ripping our the wardrobe and fitting the entire IKEA set, but it's a temporary house and we want to move in a few years. So IKEA advertises this as a 50cm unit, however the actually basket and rails measure 46cm wide. Only issue was depth, IKEA stuff is quite deep, where as the builder special junk is super shallow at less than 40cm. Send it, chopped the rails, then offset the mounting holes, job done, happy wife, less shit scattered all over the bedroom. Did the same to the other side too. Also drove the Skyline shit box today, dropped off oil at Supercheap Auto. I didn't realise they only now take max 2x bottles per visit. I visited 2x Supercheap Autos.  
    • I've seen similar actually in my situation. You never know what tables are attempted to be used when the car thinks it's -99C or +200C. The fail state is not usually that extreme but you know what I mean - it was in my case though! This is where being able to read all the sensors is useful cause you see this stuff really quickly.
    • The above is very important. However as long as you keep timing relatively low, it's plausible to make your own knock ears and plausible to learn to tune with a modern ECU that can do wideband O2 correction like a boost controller. I mean if you only have one viable road to even drive the car on, learning to tinker to this level may be worth doing given you can't do much else with the car...?
    • I find the fact that the rear plate has to be bent inwards at the rear not so bad: but the front is just awful: It's like come on. (these are my very old, now retired/turned in plates) TBH it is a lot of money to fix a minor issue, the fact I said "I'll never really spend the money on doing this" is why people ended up buying them as a gift for a 'car guy' who can be hard to shop for.. for car guy things.
×
×
  • Create New...