Allright, results time:
Peak power reading: 143kw @ 6538rpm [At the wheels]
Peak torque reading: 255Nm @ 5365rpm [At the flywheel]
Boost: 16.5psi at peak power 6538rpm, spiked to 20.7psi at 5188rpm, 18-19psi in between.
<h2>Variables:</h2>
- Only revved the car to 6500rpm and power was still increasing. Jake revved the car to 7800rpm for my previous power readouts. So I'm sure the car really makes 150-160.
- 28degree C temperature today - the other readouts with Jake were in and around winter.
- When this peak power was made, it was only at about 16.5psi. Jake WRANG the old T25 turbo out to about 19psi to make the 137kw.
<h2>Results - How does it drive??</h2>
Far out. I am absolutely blown away. NO ****. Check out the shape of the dyno graph, that explains it all. The torque curve is as far away from a straight line as you could get. The torque curve tells you how it is driving. It hits this point and goes BALLISTIC - afterburner.
The car is NOTICEABLY faster than before.
The turbo takes a little bit longer to spool up, as I always expected, the myth of ball bearing meaning quicker spool I think is mostly a myth, at the end of the day its the size of the turbo and BB probably helps it a little bit sure. But its still quite responsive. From the PSI graph you can see its already made 5psi by 3500rpm, 7psi at 4000rpm, 11psi at 4500rpm. That's laggier than the T25 by a bit, but its still quite reasonable, like the car is hurtling along quite well even with 5-7-11psi as you could imagine. But by about 4500rpm its game over and the afterburner comes on. From there all the way to the almost 8000rpm redline you can pull past an FA-18.
One of the key differences which explains how the car drives would be this: 3rd gear feels like 2nd gear used to. 3rd gear now, once it comes fully onto boost, the front of the car lifts up, like it wants to take off like an aeroplane, like squatting kind of thing, and the steering goes light. HAHAHAHA. This is 3rd gear.
In the middle of summer last time with the T25, the car would NEVER break traction in 2nd gear. It only did that in the cooler months. Today in 28degreeC, when 2nd gear hit peak boost (around 5100rpm) it broke traction a bit and was squealing its tits off, but quite nice and easy to control.
Whoa whoa go easy Mr T28bb.
One other thing I would say, maybe this is attributed to the ball bearing factor, no idea.. But even though its making peak boost later than the T25 did, it really seems SO DAMN progressive compared to before. The increase of power (as seen on the graph) just seems so factory-quality smooth and ever-increasing. Comparitively I guess the T25 felt more sudden like a bang, and this is an ever-increasing smooth injection of power.
Ben went into so much more detail and cool explanation of everything than my previous tuner. HIGHLY RECOMMENDED.
Its running a bit rich at idle because the injectors are a bit too big, but they are great once it opens up, but still only using about 60% duty cycle. He said something like my old injectors would be enough for max power, but enable a more stoich mixture at idle and better idle control. I might look at that one day, but it drives great for now, I'll just drive it for a year before I can even be bothered.
On the dyno it was only revved to 6500 and it was a hot day, but how it drives, I guarantee if my old dyno at Jakes said 137kw, this absolutely must be 150-160. Really feels a whole league above the previous setup, and still nice moderate levels of boost down low to provide some decent surging ahead of the car while you prepare for the afterburner.
Sean was correct - The wastegate properly being hooked up to vacumm really made a difference. I think because it actually makes the wastegate actuator suck back in tighter, boost builds quicker. That has made a real difference to how quickly it spools up.
Ben said the turbo is in perfect condition, its a good healthy turbo.
He said they took a lot of ignition timing out at the top end, and the mixtures were very safe, so its safe to run these boost levels no worries in squirts, just don't leave it maxxed out at 19psi for 30 minutes continuously of course.
High/Low boost controller button is amazingly useful.
The low setting has been adjusted to about 8-9psi (spikes at 11.5psi for a bit) and makes 91.3kw at the wheels. The car has come so far, it was only making 98kw flat out when I first bought it, now that is only my low boost button. Far out.
Low boost button great for: in the wet, 1st gear, and a bit of second gear, but then you need to hit the afterburner.
So I am stoked, I am thinking of just paying for a single dyno run at Jake's in winter purely for comparison purposes, because I'm sure with the combination of revving it right out, colder air, and his dyno probably being more generous than Ben's (heaps of guys at my work reckon Jake's is more generous), I reckon the readout will look pretty crazy (150-160). Its a different world to how it drove before.
I can't wait for winter. The cold air makes the world of difference, probably means another 20kw at these kinds of boost levels, safer everything. But to even floor the crap out of it today in this heat it was still so impressive. The car was always a lot more doey in the heat with the T25.
More power at the wheels than a brand new 6cyl BA falcon, and not too far off what say an XR8 puts out at the wheels - slight weight advantage 1700kg vs. 800kg.
3rd gear is a funny experience now. Prepare for takeoff, car lifts up, steering goes light. Woofta. I can appreciate more what makes the quicker quarter mile times now. Once you get in that sweet spot with the afterburner on, you gain so much time in a straight line compared to say having a bit earlier spool up and nicer torquey feeling (T25). I think it would go pretty hard down the quarter now once it got up "on the plane" as they say in boating terms. Some QUICK cars I've been beaten by before, I know it would have the balls to pull past them now.
Ben @ Intune performance did an amazing job. He gave me courtesy calls, the quality of workmanship was spot on. This air filter pipe he did up for me is really perfect. Very very tidy mandrel bends, new pod filter, fits all positioned perfectly and its in a very tidy spot. Could not have asked for a better one.
Happy with engine now, not touching anything. Just refining the car, fixing an exhaust vibration at 3000rpm, finishing off the rear cargo tray which is almost done, driving through my rego inspection like a drive thru McDonalds and then just kicking back for 2006 year of motoring.
Anyway, check out the afterburner torque curve:
