Turbo Cylinder head setup

[Flinchy]

So I should buy springs and just hope they allow me to rev out to 9k? I am well aware aftermarket springs are made for our head. I am sure other springs would fit.

The fact VAC upgraded their springs in their 4k head and made no effort to rev the engine out makes me wonder. Same with Dzenno.

AFAIK no one has successfully rev'd and N54 past 7200. Whats his face with the ST did but the stock springs broke above 8k unless I am mistaken.

no one has yet built/tuned a turbo setup that will make power past 7k

well they have, on a 6AT that can't rev past 6800...

[alex@ABRhouston]

I'm loving this thread
If I only had that time to just dedicate myself on this topic, things would be neat

[654]

The springs are capable of 10k. The head is not.

Springs are the easy part.

[alex@ABRhouston]

And why's that?

[Torgus]

The springs are capable of 10k. The head is not.

Springs are the easy part.

Please, go on.

[654]

The intake valves don't flow enough to enable high revs. There is a very limited space for both increasing the lift and/or intake valve diameter. The bore is small for fitting big valves to the area available. The stroke is long resulting in high velocity that will choke the flow at high revs. Look at VAC results. They say springs can handle 10k. So the problem is the lack of valve diameter/lift. N54 is not a high revving engine and will not be one.

Personally, I like to have the power readily available without the need to get to high rpm. Before the modern forced induction times high revving engines were the way to go. Now we have turbos that can make power at lower revs. Great.