Lithium

Very nice - actually thought it might make a little more, but that is still very healthy and should have a wicked power delivery! Look forward to reports on how it drives Is that a Dyno Dynamics dyno?

Nice, I forget - is that a 7064?

Bare with me on this, I could be off but it nonetheless sticks out to me that if 110kph = 4200rpm then it looks like it is hitting 16psi at around 4300-4400rpm. That is miles off full boost at 3400rpm, and puts it more in typical GT3582R territory - which to be fair is more like what I would have expected. Have I missed something here? I am used to Dynapacks where they can do a proper rpm vs power curve and it's a bit easier to scrutinize this kind of thing.

It is hard to tell spool from that with no rpm axis, but looks like a nice wide power band impressive power for the boost. Driven it yet? How does it go?

Nag...

Interesting. When you said 380kw on pump I started figuring the possibility it was a GTX3576R but then you said it was a GT30 which now has me completely befuddled (I only know of GTX3067R, GTX3071R and GTX3076R and you've ruled them all out!). Regardless, if it is a RB25 still then the spool you have reported is insane compared to what I'd expect from anything bigger than a GTX3071R so very much looking forward to results... or even confirmation of displacement. When will the tune be completed?

So it isn't actually a Garrett GTX turbo? Thought the same about both of you!

380kw on E85 pump gas or petrol? I would be ultra surprised to see that high on petrol on a GT30 hotside which brings me to - which GTX is it? 3200rpm for 1bar is pretty epic... and it clearly is bigger than a GTX3071R if you are talking those figures, if it is still a 2.5 then I might have to rethink what I think of the GTX if it comes together like you are saying! Watching with much interest.

To be fair your turbo would have to be one of the better matches you could get capable of hitting 300kw (on E85?) on an RB20. The Precision turbos are generally speaking targetting much more power than you are after and will be laggier than the 20G - I am guessing you want similar power to the 20G but with less lag if you can help it? His original post said he was inspired by Roy's and went a Kando equivalent originally - can even see it in my quote above

Nice :-) So what is the spec now, built RB25, GTX3071R + pump gas?

Come on boost around 3000rpm, no problem. Full boost before 4000rpm - more of a problem but maybe possible with something like an EFR7670, E85, high compression etc.

The wheelspin into 2nd won't really affect trap speeds though, if anything the heavier throttle/looser my runs the better the trap speed - big bogs were the main thing that seemed to cost me mph

I had run both with my GT30R + RB25 combo ages ago when I had external wastegate and it made no real difference to boost control or power.

Wow, awesome - no messing around! Cheers for the update

I can't imagine how people are ending up with those times, as I'd mentioned earlier I let a mate drive my car before it was tuned for more boost (probably making 260-270kw @ hubs with a GT3076R at the time) for a single run after I had pretty much hit a wall for the day at mid/high 12s - he had a stock turbo R33 GTS25t and ended up launching at too low rpm, completely bogged then when it hit full boost it lost traction/revved out like a demon compared to a stock turbo then he had a bit of a freakout going for second and ended up in neutral, took a couple of shots and third then went on his way. That lot still resulted in a 14 flat, which was the only 14 the car ran with the GT30R on it in the 4 years it was on the car. The rest were 12s, low 13s and the occasional mid/high 13 I did on complete fails - I am curious as to why these are resulting in average times and lower-than-expected trap speeds. Are they internally gated? Perhaps they don't build as much boost on the road as on the dyno or something - like the boost builds more lazily or something?

Usually it's when you miss the selection - so often miss-timing the clutch movement, or not fully putting it through the gate and ending up in neutral. Sometimes dodgy sychros, too excited or slight retardation

FP stuff has hardly ever been used on RBs, there Bri73y on here is putting a 76mm FP HTA turbo on his RB25 and aims to have that tuned in a few weeks time. FP rate their 73mm HTA compressor wheel to 54lb/min and don't tend to be over optimistic with their flow ratings. Here is an example of their 73mm wheel on a GT30 http://www.ringer-racing.com/product.sc?productId=412

I am guessing 115-118mph...

Could be turbo design, boost leak, some kind of restriction - is it ball bearing? What was the temperature like on the day by the way? Also, what kind of dyno was it tuned on? One of the reasons I said anything is mine was trapping higher and running quicker times (14.0 @ 110mph even with a TOTAL bogged launch - ~3s 60ft, then missed second gear completely etc when a mate who has a stock turbo R33 had a go) with ~260-270kw @ hubs on 15psi and going by most people here's comments etc that power should be about equivalent to 240kw "Oz dyno" type numbers. Regardless, I remember when I was running 108-109mph in my car - doesn't make for a slow car by any means, no doubt well worth being happy with but in one way or another it potentially could be a bit quicker with that power.

Awesome! Good luck, looking forward to results

Thought it sounded like that, seemed to take quite a while to come on in first and a it didn't sound like it came to life in a huge rush in second either... Obviously hard to tell watching the clip but it got my attention. If you spend a reasonable amount of time building boost when raving then you don't get the full power curve the dyno suggests that you have at your disposal.... Which can definitely affect real world performance, ie lower trap speeds than expected for a power level.

What is boost recovery like in gear shifts? Does your car have a screamer pipe? Hard to tell from the clip

Was that with 360whp? Those trap speeds are way lower than I would have expected!

There look like there are too many variables between those setups to be able to get a gauge of what the different turbos have done.

No kidding. I hope it pays off! Should make good power, though I'm really looking forward to seeing the power delivery and hearing how it drives - it should be a bit of a beast.