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All good man just having a friendly dig.. :thumbsup: Back on topic...

Fair enough... was a bit cheeky though! ;) I am a bit of a nerd especially when I don't know something, come hell or high water I want to know exactly what and how happens.

To rob82 my comments were more to suggest that an internal wastegate creates more back pressure on the exhaust side. I also think you answered your own question as well... why would you have a large frame single turbo on a small capacity engine with small cams? Engine would choke before the turbocharger even came into its own.

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Fair enough... was a bit cheeky though! ;) I am a bit of a nerd especially when I don't know something, come hell or high water I want to know exactly what and how happens.

To rob82 my comments were more to suggest that an internal wastegate creates more back pressure on the exhaust side. I also think you answered your own question as well... why would you have a large frame single turbo on a small capacity engine with small cams? Engine would choke before the turbocharger even came into its own.

I honestly think that most internal wastegated turbo would cause less flow disruption/diversion at the point of gating than most externally gated setups. Hence the exhuast backpressure would be less for the same size turbo with an internal gate vs external gate.

Also I was just trying to point out before that if response is the goal massive cams are not the go.

No better example of this than ole mate Marko really.

About time you did, everyone will benefit.

I mean you supposedly asked for a tune without a midrange...

And are firmly on the big cam bandwagon this month:

Yet only 2 months ago you come out with this?

Says it all really. :rolleyes:

i am not prepared to go into detail of my old engine setup as it is not my business to share this intell, however, i will tell you that the engine is running 100kw less - case closed.

my cam choice has ALWAYS been chosen by my tuner - not what i read on the internet from a computer warrior. for example, would someone who has built many rb's (i.e. CRD, RIPS, Red R Racing, Hi Octane) carry more weight than a someone like yourself or me for that matter? stop kidding yourself...how many engines have you built ash & how many combinations have u personally tried?

i have had this thread reviewed (not disclosing name) i am sure you will keep following me around as its blatantly obvious, please stop trolling and posting off topic as this is not the 1st time.

thank you & sorry guys

I honestly think that most internal wastegated turbo would cause less flow disruption/diversion at the point of gating than most externally gated setups. Hence the exhuast backpressure would be less for the same size turbo with an internal gate vs external gate.

Also I was just trying to point out before that if response is the goal massive cams are not the go.

Sorry mate you are wrong there on your first paragraph.

Yes, you want response choose small turbos like HKS GT-SS or N1 upgrade (which means high exhaust manifold back pressure) and chosing short duration camshafts with little or no overlap.

Sorry mate you are wrong there on your first paragraph.

Yes, you want response choose small turbos like HKS GT-SS or N1 upgrade (which means high exhaust manifold back pressure) and chosing short duration camshafts with little or no overlap.

Can you explain why I am wrong.

I dont think you understand what I am saying - try reading my post again.

Under the assumption that the external wastegate is vented to atmosphere your theory is incorrect.

Arguing with you is like masturbating with a cheese grater - slighty amusing but mostly painful!

WTF are you talking about.

  • 2 weeks later...

Real world data. Rb26 at 86.5 bore, stock stroke, all steel internals (endurance spec build, probably overkill, but I hate failures), Tomei 280 degree 10.8 mm lift cams, Tomei cooling channel pistons at stock CR, Motec M800 ecu, stock TB's, stock CR, mildly ported head, all manifolds port aligned, stock ported cast manifolds, NO AFM's, MAP / Throttle based but with 4D mapping, stock elbows, -10 turbos, 3 inch ultra quiet exhaust (98Db at 2/3 max rpm static), 850 CC injectors off single 044 pump, in a GTS-T RWD shell. 1.2 bar boot. Motec shows absolute, not gauge pressure. mikey whatsisname speaks a lot of sense, IMHO.

http://www.gatesgarth.com/datalog.png

In car with basic data overlay from same track day:

Manually synched to video, so a tad out, sorry.

I want to try the bigger -10 turbine housings. Car is a pussy cat on the road, no shuffle at all, totally pleasant off boost and at cruise. Would benefit from a less restrictive exhaust system, exhaust manifold pressure V boost pressure ratio is not brilliant, but here in the UK noise is a major issue. Car runs from the roadside pump Shell V power, no det, no issues.

Edited by Chris Wilson

I think your throttle % mapping is a bit out, highest it gets too is 65% or so whilst the 'bar' is maxed?

5500rpm in second @ full noise before 1.2bar. Maybe you need 290 cams as well to bring them on @ 4500rpm like some around here have claimed :rolleyes:

Pity the data cuts out half way through the video man, it was just looking to get interesting :(

Yes, I am just trying this manual data overlay app (Race Render, it's me, not the app as such, it's trickier than I imagined...), I am beginning to wonder just how far from synched this is, take it with a pinch of salt, but you get the basic idea. Just shut one eye ;) Automagical synching is available from Motec, but the bank manager is dubious about its merits this month ;)

I am in the UK, but try and keep an eye on all the Skyline sites. Cheers. I may have another go at doing a better synch. I have sold my Go Pro Hero camera and for next season will either get the Motec stuff if they come good on their intent to offer a higher resolution camera setup, or buy a camera that time stamps the video. The GPS data channels have a GPS time function, so tying up the two should be far easier then. Cheers.

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