No power gained from 4.7L srtoke

[Basselalawar]

Hello,
I have a 4.7L 1998
the engine is healthy with no issues, I have hesco throttle body, Gibson headers, 4 hole injector upgrade. the current piston compression ratio is 10:1. I have small gains compared to 4.0L and the engine cant rev to the rev limiter. Didnt do any tune or cps mods.
help is really appreciated

[Sean295]

I assume you have a after market cam..if so you will mos likely need to index the distributor.

Was it running fine to start with and something happened or is it a new build?

Try a compression test...make sure your building pressure....make sure your getting plenty of fuel by checking the fuel pressure...those fuel pumps are not the greatest....spark is the next thing...

[papaof2]

A tune from frptuning.com / Flyin' Ryan Performance will make all the difference.

[SkylinesSuck]

Not if it's not running right first. Ryan won't want to touch it if it isn't. You should see a very noticeable increase in power across the board even with no tune. Do you have a wideband O2 sensor to tell you what your fueling is like? What injectors are you running?

[astjp2]

Is the catalytic converter clogged? My stroker runs like a scalded dog...

[tablerockfshr]

I had the same thing till I upgraded the fuel pump on a 99 xj with 24lb injectors ...just my situation,,

[Cheromaniac]

If the old fuel pump is weak, a new stock replacement would do fine. Rated at 90lph (24gph), that's enough to fuel a 300hp N/A engine.