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That is fairly true.. Stao himself has said the SS2 is intended as a low shaft speed turbo. Maybe velocity is too high through the head now, and the turbo is being over spun. Thus giving the effect there is a restriction..

I wouldn't say "too much" porting....

Yes we did go excessive for his current setup, knowing that in the future we were going to go bigger...

Lastnight we plotted blah_blahs engine on a GT3076 and it is coming up too small, its outside the efficiency island and in overspeed...

Blah_blah wanted a race engine and thats what he has...

The engine wants to rev, now the bolt ons need to support this!

(And im jot just referring to turbo, there are many other areas that need attention)

I have no idea what goes into this calculation but it was a couple of pages long and its a bit over my head, and I failed physics in highschool lol

So this is the plot of my engine against a GT3076 compressor map that was calculated and given to me last night based on my engine

1002563_689889264358769_299315121_n.jpg

Basically what it means is "you need more flow bro"..

From your turbo that is, your head has enough already. :laugh:

I may be wrong here but It doesn't necassarily mean you need a huge turbo, it may just need something that flows faster...like. GTX will flow faster than a GT ..still might not be enough for you though ..But you can look at larger turbos anyway because your head flow will allow it to spin up much quicker which in effect will make it feel and respond like a smaller turbo..if that makes sense...

This car is internally gated, I have a feeling that it is the turbine end that has been maxed out. My car behaved differently when compressor is out of flow. Assume it is the case, by running a larger compressor wheel (ie going to a billet SS3 region) will only encourage the worse part of this issue.

A major stepping up from a SS2's turbine is the G4's turbine, and we can fit a SS3 compressor making it a SS3.5 in a .82 rear. Then that would be capable of high revs, how ever laggy for street. Unless running VNT setup internally gated.

No it won't be laggy on this Stao because the headflow will allow it too spool much quicker...yes it will come on late in the rev range...but the head flow will allow it to get to that rev range much quicker ..

Just think of it as a normal rb head being a restriction and now that restriction is gone ..;)

its not just about moving more volume its about moving it faster and for longer

I wouldn't say "too much" porting....

Yes we did go excessive for his current setup, knowing that in the future we were going to go bigger...

Lastnight we plotted blah_blahs engine on a GT3076 and it is coming up too small, its outside the efficiency island and in overspeed...

Blah_blah wanted a race engine and thats what he has...

The engine wants to rev, now the bolt ons need to support this!

(And im jot just referring to turbo, there are many other areas that need attention)

I think you are missing the point of a race engine, they don't need to rev to 11ty, they only need to be built strong and flowed to suit the turbo. I assume Tony isn't going to fit a GTX45 anytime soon so the stock heads would have been fine with just a clean up. The cooling side is much more important.

Now e85 is available, and any track car owner in their right mind would be running it, there is little need for crazy port jobs and long duration cams imo. Early spool and massive efficiency curves are where its at, track or road...

This car is internally gated, I have a feeling that it is the turbine end that has been maxed out. My car behaved differently when compressor is out of flow. Assume it is the case, by running a larger compressor wheel (ie going to a billet SS3 region) will only encourage the worse part of this issue.

A major stepping up from a SS2's turbine is the G4's turbine, and we can fit a SS3 compressor making it a SS3.5 in a .82 rear. Then that would be capable of high revs, how ever laggy for street. Unless running VNT setup internally gated.

How do those turbo compare to say a GT3582? As i think on the compressor map that turbo was a better fit

No it won't be laggy on this Stao because the headflow will allow it too spool much quicker...yes it will come on late in the rev range...but the head flow will allow it to get to that rev range much quicker ..

Just think of it as a normal rb head being a restriction and now that restriction is gone .. ;)

its not just about moving more volume its about moving it faster and for longer

That makes sense Dave...i think haha

I think you are missing the point of a race engine, they don't need to rev to 11ty, they only need to be built strong and flowed to suit the turbo. I assume Tony isn't going to fit a GTX45 anytime soon so the stock heads would have been fine with just a clean up. The cooling side is much more important.

Now e85 is available, and any track car owner in their right mind would be running it, there is little need for crazy port jobs and long duration cams imo. Early spool and massive efficiency curves are where its at, track or road...

It's still a street/track car, don't want to go e85 yet

I do still enjoy long drives in the Skyline without needing to carry 4 x Jerrycans in my boot :P

And if your going to mention a flex fuel setup, moneys tight when your married and got a mortgage :/

I think you maybe right hypergear, I dont think the internal gate is doing many favors, by no means am I suggesting your product isn't a good product, im just saying for this application we are pushing some serious boundaries...

As for what a race engine is, im not saying it has to rev to 11k, but the last thing any engine needs, especially a track engine where WOT is held for long periods is high brake specific mean pressure!

Strength is one thing, durability is another...

With the right size rear housing this engine will hold 7000+RPM for a lot longer then any stock motor will before reaching any problems!

If you are chasing a 300rwkw car there is no use building a motor that will max out at 300rwkw!

The idea is to build an engine that will stretch to 350+ and then detune it...

That there is strength and reliability!

Why would you need 4 jerries? you driving to Wakefield?

I realise those flex fuel sensors are soooo expensive, but I don't think $50 is going to upset the new wife too much. :P

lol.

I will have to keep working on you it seems Tony. :P

Maybe one day when I can drive like Richo ill go e85 :P

In the mean time pending on some dyno diagnoses I might be paying Scotty Customs a visit to fix any cooler/exhaust issues :D

Or even a custom/modded airbox if that is a restriction

Anybody know the restriction on a stock R34 GTT airbox with panel filter?

As far as I am aware they are not as big as the GTR one and don't have a bottom/side feed

I think you maybe right hypergear, I dont think the internal gate is doing many favors, by no means am I suggesting your product isn't a good product, im just saying for this application we are pushing some serious boundaries...

As for what a race engine is, im not saying it has to rev to 11k, but the last thing any engine needs, especially a track engine where WOT is held for long periods is high brake specific mean pressure!

Strength is one thing, durability is another...

With the right size rear housing this engine will hold 7000+RPM for a lot longer then any stock motor will before reaching any problems!

If you are chasing a 300rwkw car there is no use building a motor that will max out at 300rwkw!

The idea is to build an engine that will stretch to 350+ and then detune it...

That there is strength and reliability!

i think what Scotty is trying to say Mik is that the stock rb has the flow capabilities to out match nearly any semi-serious track driver..

I mean look at Richo hes quicker than nearly anyone "on the track"and hes only running a stock RB with a small turbo...

Even Russ is using a stock RB with a 3076 and these are 2 of the quickest RB25 guys in Australia...how fast do you really think it can go :laugh:

I like what you have done and Tony's engine has the capabilities of some very high speed now, but Scotty is right, it will go to waste on your average racetrack.

Fast and Furious style freeway runs however it will decimate all...especially with 2 of the big one ;)

.Just big turbo it and head for the drags on e85.

Tony you have two cars just get on ethanol lol

Civic is a pos

Didn't even start his morning lol

i think what Scotty is trying to say Mik is that the stock rb has the flow capabilities to out match nearly any semi-serious track driver..

I mean look at Richo hes quicker than nearly anyone "on the track"and hes only running a stock RB with a small turbo...

Even Russ is using a stock RB with a 3076 and these are 2 of the quickest RB25 guys in Australia...how fast do you really think it can go :laugh:

I like what you have done and Tony's engine has the capabilities of some very high speed now, but Scotty is right, it will go to waste on your average racetrack.

.unless you big turbo it and head for the drags on e85. *hint hint*

I get what your saying that I'm a crap driver. Ain't no dispute in that :P

But I thought whilst the head is off I may as well do it. *insert doitphaggot.gif* so in the future I wouldn't have to do it again if I decided to chase a crap load of power for the lolz. Know what I mean jelly bean?

I get it, and I under stand a standard head will flow good enough, but this engine isn't wss based on "good enough"

If you were getting an engine built, and the set price was X amount for a standard build, but you had the option of a race set up at no extra cost, what would you choose?

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