Evo X upgrades

[scheides]

Dang, was hoping to see what a BBX would do on stock cams & E85 Oh well, doing it 'right' is never a bad thing! Valvesprings can be done w/o pulling the head, but its a bit tricky. The cams on an X are so mild I would think that even the stock springs might be able to deal with an elevated rev-limit, even on aftermarket cams. I know Gates runs his stock cams to like 8200 regularly w/o issue.

Seems as though ~420whp on shane's dyno is the accepted safe limit of the evo8/9 7-bolt bottom-end. Even then I know one person that saw stretched rod bolts but those may be due to extenuating circumstances (meth fail). Evo X's 4b11 on the other hand seem to be beefier all over on the bottom end..I would expect 450whp (dyno dynamics) to really be closer to the 'safe' limit as long as torque wasn't over ~400 and the motor didn't see over 8000rpm much. It's for this reason that going 'all out' on the X is really not a bad choice and at the same time, makes me wonder if upgrading the snail on my car is a good idea

[mlomker]

Originally Posted by scheides

The cams on an X are so mild I would think that even the stock springs might be able to deal with an elevated rev-limit, even on aftermarket cams.

So far in life my cars haven't rewarded me much for going one notch to the safe side but I still tend to do it. The MX1 is a mild cam and doesn't require springs but if I were going to up the rev limiter then I'd do the mild cam + springs.

In my mind the head studs & rod bolts are a given. I had a very reasonable quote from DG Motors for doing it ($300 when doing cams) so if a local shop can do it then that's cheap insurance.