Losing Power around 5000 RPM

[4G63allday97]

I just got my 97 GST tuned, my mechanic said I have perfect compression, fuel, timing, and no boost leaks. My car is running 22 PSI and he told me once he ran it on the dyno he ran 4500-5000 RPM's I dropped down to 20PSI and my car felt like it was losing power. My dyno readout ended up being 220hp and 255tq. The power is definitely there but he says he thinks that there is something up with the engine but he couldn't seem to find the problem. I've been reading throughout these forums looking for a person with the same problem but I couldn't seem to find one. Does anybody have any clue as to what would cause my car to lose power in this bizarre way?

 

[98_tsi_]

If your mods are correct what dyno are you using? And what is your af? If not tuned you could be pooring fuel around that rpm causing it to lose power. 220hp and 255tq seems a little low for those modifications

 

[blackeagle92]

Does sound like a tuning issue. Can you post some of your other mods?

 

[4G63allday97]

I went to a tuning shop that specializes in DSM's and they use a awd mustang dyno. He tunes cars like mine all the time but this is the first time he's seen a car perform as poorly as mine. He says its like there's a restriction to getting the rest of my power my car should have. He was suggesting it could've been my cams because I'm running stock. He was saying I should use the hks 272 cams, but something is telling me it's not the cams that are causing this problem. And I don't know my af unfortunately. I was thinking the same thing, my mechanic was saying I should be in the 280 range close to 300

Other than what I have for mods that's pretty much it.

 

[91-GS]

Doesn't DSMlink have an A/F logger of some sort?

 

[4G63allday97]

It's supposed to, he literally said he checked everything over like my compression, fuel, and timing. I also didn't have any boost leaks. He sent my stats to ECM tuning and they even said that they had a car similar to mine but the found the problem and it was timing. I talked to two professionals that deal with dsm's but no one seems to know anything about what's going on.

 

[DAO 1950]

I didn't see a wide band af in your profile. If you don't have one it will be difficult to tune that thing. With the V3 you have control over the fuel and timing but you have to monitor the running engine in order to make the proper adjustments.

 

[98_tsi_]

Honestly with those mods you should be over the 300 mark tuned....what compression ratio are you running? Is the air filter super nasty??? Mustang dynos read a little lower anyways but it shouldn't be that low. Was the dyno calibrated? What does link say you are logging?