Originally Posted by dan l

I’d have to say that’s not true. I just did some datalogging on my friends ’04 Evo. On his particular car we could’ve just cranked the boost to 24 or 25psi on the stock maps. They are so rich and conservative with timing that it’s no big deal. I ended up leaning out the maps more than 2 air/fuel points in the upper RPM regions from the stock map. I kept the stock timing map the same because I liked it. It keeps a bunch of the burn energy in the exhaust manifold which is ideal on volatile pump gas. We then started raising the boost until we could get just a little bit of knock. For some reason you guys worry a lot about the boost spike. Unless it causes knock ignore it. He posted above that it spikes to 25 and holds to 23. His knock count is between 1-3 at 6500 rpm’s or so. This is an insignificant amount. We could run 25psi on the car for drag racing no problemo. If your not knocking your not trying. His only mods are a Joe P MBC and a Buschur catback.

Also whats the deal with boost anyways? 24psi on stock cams vs 24psi on a set of cams is not the same thing. The fact that you are using boost levels as a criteria is showing me that you don’t have a grasp on what causes problems.

Now if your modding your car and aren’t watching your knock sensor your asking for it regardless of boost levels. I’ve seen stock DSM’s blow up on stock turbos and 14psi boost in nearly stock cars. I’ve also personally ran 26psi on pump gas in my very modded stock motored 1990 eclipse w/161K on the clock.

Furthermore ARP’s aren’t as necessary as everybody thinks. First putting them in one by one is a hack job. You can do more damage than good. Pull the head and do it right.


Have a good day....

danl
11.80 at 126 stock bottom end stock head stock cams

Originally Posted by RedLanEVO

man i run 25 psi all the time..says my autometer gauge.