Hi guys, I have an Evo 7, and when I rev up the engine in neutral, it seems quite slow. It gets slower as the RPM climbs, anything past 3k it seems to be slower.

this is relefect when doing a pull, from 2.5K, the car runs great until 3.5k where the rev rate starts to slow down.

I free reved an Evo 5, which is almost stock, stage 1 I guess, it reved more happily too redline.


Any suggestions on what to check? could it be plugs, ignition coil? or the restrictive stock outlet and down pipe?

Mods in sig

 

I would suggest doing a compression test. If the compression isn't normal then there lies your problem. If its normal then please give more info, i.e does it cut off at any point? Smoke? Etc..