Similar cars, One's got power till 7k, the other till 6k. Why?

[disciplekyst]

Here we go:

I own a talon 90tsi awd that's got a 2,5"exhaust (ported wastegate/no creep), stock SMIC, UICP and K&N --> I put pretty good power to the ground but the car feels sluggish past 6k, which I think is normal. I can't run more than 15psi because of knock.

My friends car's has the same exact setup (14b etc) but can run 18+psi and has incredible top end power (i'm not kidding)

SO, we were thinking that maybe one of the previous owners put in an unknown mod that allows my friend's car to run that strong till 7k+. What mod could allow that? Cams? advanced timing?

Put another way, what could make our cars run strong till 7k when the majority of DSMers shift around 6200 due to power loss at top end???

Thanks guys

 

[Boost92awd]

Just because hes running more boost dosent mean hes making more power, its all about the tune. Running 18 PSI with no tune is probally not a good thing, tell me he atleast has a logger. Your friend could have an upgraded fuel pump or maybe its rewired. If you want more top end cams could help you out with that. Also check out the upgrade path.

 

[crimsondragon]

It could be anything. Maybe your combustion chamber has a lot of carbon buildup limiting the amount of boost you can run. Maybe his car has better internals, or was recently rebuilt. Who knows. Only way you can find out is tearing into the engine.

 

[dsm03]

On the same note, every car reacts differently to mods.. some cars will be better potential than others and im speaking on identical cars... Considering the age of the vehicles as well, he could have better maintenance along the way only way to tell to is do a compression test see how well your engine is performing...There is a lot of variables that can come into play

 

[wishnfor4g63T]

Boost leak test it. That could point out the problem easily. Another thing me and a friend discussed are you running the same octane? Their are alot of variables to make one car run diff from the other!

 

[hdoerr]

It could have aftermarket cams which would cause the powerband to be extended. Most likely though a combination of the things the others have said will make the diff.

 

[disciplekyst]

Ok thanks guys,

BTW I was not complaining on the way my car runs because I know it's fine.

What about you guys, do you feel a power loss after say, 6500rpm? Because I can tell you that in his car, you feel like you could go all the way to 8k (He doesnt do it dont worry).
We noted that his idle is a little crappy and throttle response below 2k is really bad, so I think we're talking about cams here... What do you think?