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I've got 256 8.8mm/264 9.0mm HKS cams in mine. I saw a peak power gain of 20rwkw - dyno'd before and after, same day, same dyno.

Cheers for that mate 20 rwkw aint nothing to be sneezed at, i was actually thinking HKS cams also. Did you have to replace valve springs?

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I took the big lumps out the head exh ports, and exh manifold, didnt bother with the inlet manifold as it was pretty good match, what did you do?

I left the lumps in the head as Chris miltons who did the head work said they are there to help with flow in the std log manifold. Not sure if thats guess work or what not.

They smoothed them out, ported polished, valve deshroud and multiangle valve job. I remember mentioning they work the inlet valve job different to the exhaust due to the reversed gas flow.

Noticeable difference before and after when feeling around. Set me back around 1.1k.

I made everything spot on. Any little lip I removed it.

You didn't match the turbo to exhaust manifold? As that was the biggy. See pic attached.

I couldn't help myself as I visualised the exhaust gas smashing in to the flat edges, causing turbulence and killing power. :)

post-382-1228209509_thumb.jpg

Waves in dyno runs are generally only ever the result of a control system problem inherent in the dyno. If not you would feel them on the road.

The way to properly test whether an intercooler is too small. Its very simple, and doesnt - much like your engine - take into account anything other than the pure physics of the situation - plug a pressure feed in each side of the the intercooler. The Mainline uses both its pressure sensors to then calculate a channel called 'Pressure Drop' which graphs against power or other data channels to show you exactly how or even if the intercooler is holding you up :)

I left the lumps in the head as Chris miltons who did the head work said they are there to help with flow in the std log manifold. Not sure if thats guess work or what not.

They smoothed them out, ported polished, valve deshroud and multiangle valve job. I remember mentioning they work the inlet valve job different to the exhaust due to the reversed gas flow.

Noticeable difference before and after when feeling around. Set me back around 1.1k.

I made everything spot on. Any little lip I removed it.

You didn't match the turbo to exhaust manifold? As that was the biggy. See pic attached.

I couldn't help myself as I visualised the exhaust gas smashing in to the flat edges, causing turbulence and killing power. :thumbsup:

Yeah checked that one, The IW housing i had on my turbo was already larger than the manifold.

while my head is being done, should I take a porting tool into the stock exhaust manifold?

worth it or not, to clean up the insides of a stock manifold?

itd just be with a drill bit type metal sander, to polish the edges and insides as far as possible.

always thought I should do it while the head is being done....... thoughts? any point?

Curious how Guilt-Toy is getting 370rwkw odd out of his 740 injectors on E85. :S

Lambda .86 is considered max power lean (which your already sitting on) so who knows. :S

A little OT but this injector size calc.

http://www.megamanual.com/flexfuel.htm

500hp needs 71lb/hr injectors. 71lb/hr is 750cc. 300rwkwish is around 500hp at the fly given the DD Dyno estimate 70-75rwkw drive train loss.

550hp = 830cc

600hp = 900cc

Thats a lot of injector. Nothing a little fuel pressure can't fix. :thumbsup:

I thought he said he tuned it to 340rwkw on E85, and was a little vague on the duty dycle, seems to remember somewhere it the 80% range i think, could be wrong. Also he's running 2 pumps, an intank feeding a external bosch, where as i'm only running a internal tomei, cant say what pressure he's running nor mine for that matter i've just turned the nismo fpr 3/4 of a turn on from where it was when new! I have a theory that I may be tipping in a little extra fuel to compensate for the extra heat my little comp covers making! sounds good.

Edited by 180or200
also changed from 600x300x 76 thick cooler to a 100mm thick version and it made the exact same power....

My old intercooler was a little over 50mm thick, not as aesthetically pleasing to me as it once was, and I wanted to go to a 600 x 300 x 100mm item - for the price of a decent intercooler of this size these days it's a no-brainer.

I thought he said he tuned it to 340rwkw on E85, and was a little vague on the duty dycle, seems to remember somewhere it the 80% range i think, could be wrong. Also he's running 2 pumps, an intank feeding a external bosch, where as i'm only running a internal tomei, cant say what pressure he's running nor mine for that matter i've just turned the nismo fpr 3/4 of a turn on from where it was when new! I have a theory that I may be tipping in a little extra fuel to compensate for the extra heat my little comp covers making! sounds good.

I recall a figure of 340rwkw on E85 from Guilt Toy too.

A 'mild' single pump upgrade and a slight increase in fuel pressure probably means you've got a bit left in reserve if need be.

I'm going to opt for 870cc injectors, that way I've got plenty of headroom should the need arise at a later stage down the track.

yep. 2.6 litre torque :rolleyes:

Thats a super fat curve, with that sort of torque who needs gears

I recall a figure of 340rwkw on E85 from Guilt Toy too.

A 'mild' single pump upgrade and a slight increase in fuel pressure probably means you've got a bit left in reserve if need be.

I'm going to opt for 870cc injectors, that way I've got plenty of headroom should the need arise at a later stage down the track.

what are these 870's, are they drop in side feed?

gallery_34685_2975_43658.jpg

If Martin comes back, could you tell us what the numbers on the left of the derived torque are and how they relate to the peak torque figure written in the middle between the graphs ( much higher numbers )?

what are these 870's, are they drop in side feed?

Adrian, they're Siemens 870cc top feed injectors. I have a custom top feed rail - so much easier when searching for injector options.

Siemens Racing Injector, designed for Aftermarket Performance Applications

Suitable for 175HP per injector in Non-Turbo Applications

Suitable for 139HP per injector for Turbo and Supercharged Applications

83 lb/hr (870cc/min)

14mm O'Ring

Low Impedance (2.2ohms)

Uses Bosch Style Square Connector (EV1)

Also Suitable for Alcohol (Methanol)

While we're on the topic of 870cc injectors and Guilt Toy's E85 beast, I see he is selling a set of 870cc Sard injectors.

Here is a great example of what you can do with a 3 litre RB series engine if you set it up and tune it correctly across the whole rpm spectrum, optimising for Mean Best Torque.

The interest to be taken away here is not in the 652rwkw (875rwhp) but in the difference between roller measured torque and derived torque calculated back from the engine rpm :whoops:

32gtros.jpg

Pure or roller torque is in the region of 1420Nm from 6000rpm which gives the engine plenty of pull towards the redline, but is hardly an accurate indication of actual torque. Now we bring up the derived calculation, which shows a closer and more accurate 880Nm. You can see there is a very big difference between roller torque - the way some here have been looking at their figures - and derived torque. I think actually looking at this we have a new Skyline torque winner as well :)

We should have some more figures very soon from a similar engine and turbocharger package we are engineering that will achieve the 1000Nm derived torque figure. As some have been heard to say, 600rwkw, its yesterdays 300rwkw :yucky:

Edited by Martin Donnon

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