My RX7SP build up

[RICE RACING]

Originally Posted by Libor

This goes hand in hand with what has been observed here http://www.rx7club.com/showthread.php?t=987107

But it still leaves me with scratching head, same tune, same boost, almost same observed AFR and IAT so we can assume same airflow, but at the one point, pre-turbo produced about 10% more power. Maybe just post IC or port injection quenches combustion and hurts cycle a bit more than pre-turbo?

Another thing to propose to Barry for testing

I doubt you will find any formal text book explanation on this.

All I know is that in ~1994 when I tested this only pre turbo gave an acceleration increase. I later confirmed this to much higher detail when I got my VBOX equipment. The way I do it, it just works, it's flattering to see so many people now copying it word for word part for part spec for spec......... and like now its some kind of amazing discovery when I was 20 years ahead of the game lol.

Lots of great tests were done on this though in the 1960's and 1970's with the fore fathers of after market turbo charging and running WM50 (all pre compressor), find some books called How to select and instal Turbochargers by Hugh McInnes > http://www.amazon.com/Select-Install.../dp/0912656050
^ I have an original of the above book! it is worth buying from a historical stand point alone....... I have all of his others too. And this is where I got the idea to try water injection myself when I was a kid still. There is a fantastic book > http://www.fefcholden.org.au/techinf...rge/index.html a good friend of mine lent me his book *he is the man with a 36psi 1970's old Holden in line 6 running tripple SU carburettors that I VBOX tuned and tested in my Aquamist thread)... All these pioneers ALL talk about water injection and its benefit and all run pre compressor.