13B Power @ 1 bar absolute pressure, to see what you might have if you MAN UP!

[RICE RACING]

So the base engine (aside from mechanical strength!) was and is never the issue, its the bolt ons and adaption of water injection or aftercooling spraying to keep charge temperature under control and so long as you have the appropriate turbo its a prefect linear relationship.

It is and can be swayed by these variables:

* If you are greatly reducing ign timing as boost increase
* If you are making vast changes to AFR as boost increase

Then you can have non linear discrepancies of over 25%!!!
But if you run water injected especially these boundary restrictions do not apply

To give you a practical proven example a BMW F1 turbo mapped on an engine dyno here (I have the dyno sheet!) is Australia did 802bhp @ 3.3bar with lambda of 0.79 @ 10,000rpm and at 5.6bar uses the same lambda and water spraying the IC it see's over 1350bhp That was the going rate at the time for the qualifying power output at that boost pressure

[Mitchocalypse]

Well I'll be darned

I gotta say, the thing I like the most about your posts is that you explain the theoretical side of things and then follow it up with an example that agrees with what the textbook says.

[RICE RACING]

Originally Posted by Mitchocalypse

Well I'll be darned

I gotta say, the thing I like the most about your posts is that you explain the theoretical side of things and then follow it up with an example that agrees with what the textbook says.

Thanks

That is how I teach (It's my profession) it adds credibility and separates the wannabe's from the ones who actually have done it

I like many others get sick and tired in forum world of reading crack pot theories or regurgitated information by overnight wonders who have never done anything of the sort. My idea is to understand the theory and then apply it myself, THEN talk about it. And back it up ........... odd concept I know to some lol.

You asked an excellent and insightful question before and I hope I explained it, back when I was doing tests on the standard ports and collecting data on everything I personally saw near a linear rise to the point where there was divergence between TIP and MIP (turbine inlet pressure and manifold inlet pressure) *read turbo becoming too small* so then I experimented with 1.00 to 1.15 and to finally 1.32 A/R turbine housings then to the point of the turbo itself being too small. So that is a critical point and lots of good engineering writing on the subject explains balance of gas flows between turbine to compressor. Second "mapping" considerations which lots dont talk about is excess fuel ratio's and spark timing, and tertiary considerations are the charge temperature and knock limitation of the fuel you use relative to the CR you choose to implement (inter related issues to a point).

But if all things are appropriate for the target goal then sky is the limit, so long as you do not exceed thermal capacity of critical engine components or mechanical strength, and it is advantageous to keep rpm low and vastly increase pressure as this is far far less stressful.

Wanted to keep it simple though, but hopefully this explains the "theory" is sound and proven in reality too

[RICE RACING]

Forgot to add, the real world examples I give are using stock std Mazda inlet manifolding.

edit *too much info!* you dont need to know and all of your real performance increases come from raising the absolute pressure to the level you need to make the power you want