First, I just swapped engines about three weeks ago.
I hadn't really ran it hard so I never noticed until last weekend when I went touge-ing.
I already replaced both fuel filters.
Whenever I try to accelerate past 4,500-5,500rpm it hits a wall; won't accelerate anymore.
Good acceleration all the way up until then, though.
Sometimes it will redline, but not very often.
I've got no engine codes anymore, fixed my last one (engine air temp sensor).
Every now and then I'll get a check engine light but it only flashes on when cruising around town, and goes off very quick. Is never stored I suppose.
I have a walboro 255 and it is a mild streetported n/a (no real mods).
I have the fuel pump wired directly to the battery on a switch because my last engine would flood due do low compression.
I'm confused because if the fuel pump works when I check it, it should always work; right?
I had a post when I first noticed the problem but I was told a thousand times it was because of an OMP limp mode.
I've had my car in limp mode, I know what it is like.
Also, I never had the codes for the OMP; I had mis-read them.
If anyone can decipher my crappy thread and try and diagnose my problem that'd be great.
I'll probably go ahead and swap a n/a s4 stock fuel pump in tmrw and see what happens.

 

What does it feel like when it stops accelerating? Does just hesitate? Is it very jerky? Does it make any different noises?

I have a hard time believing a fuel pump would cause an RPM specific problem, especially if its been rewired.

 

What's your fuel pressure look like when you have this problem?

 

Sounds more like ignition to me?Do you have a amp?

 

That Walbro pump is over kill for a n/a. Stick with the stock pump.

 

Fuel pressure is fine, no amp, and the walboro came with it.
It just smacks a wall.
When it hits it doesn't jerk, backfire, etc etc.
Sort of confuses me.