Originally Posted by paul98itr
Yes u need the valve springs because you are able to rev to 9100 which is a rpm range vunerable to valve float. The ecu is an awesome up grade if you are going to run fairly stock. Throw mugen headers and cat-back and their air box, and that is how it is made to be run. If you want to do internals, you are better off with like the hondata or aem plug and play. The mugen way is a fun reliable way that you don't have to worry about the problems of supper tunning, and is a good increase in horsepower. Lots of people think it is to expensive though. It is up to you. I was very satisfied when I road in a car set-up like above.Hope this helps.
The Mugen N1 ECU was made to run with JDM ITR compressioin, Mugen cams, a Mugen valve train, plus their headers, more fuel, and also more timing. I wouldn't call that close to stock. It makes a good baseline ECU, but as far as just plugging it into an almost stock car, if anything, other then the rev limiter changed, it would probably slow the car down, and as long as you don't push it past like 8900, you really don't need the valve springs. To add a note, valve float doesn't occur at any specific RPM range, it's ussualy when you have a cam with a higher lift at higher RPMs, on stock cams, you really don't need to upgrade valve springs to run that ecu, just don't make it a habit to bounce the rev limiter.
Later,
Aj