Why can't I have HP?

[Instigator99]

So I went to the tuner today to get my setup off the base tune, had some issues. Here are my mods:

Posi ported eaton
2.76 upper
4lb lower
4 piece idlers
80lb injectors
BAP w/ wiring upgrade
jlt rai
magnaflow o/r x-pipe
borla stingers
ported dragon tb/plenum
reische 170* tstat
sct ba2400
03/04 NOS plate kit

At first we were having issues getting the maf to work, turns out the iat sensor was unplugged, have been driving the car like that for the past few weeks, including a track day...my bad. The base tune from Amazon was for 91, ran a tank or two of e-30 blend, but was full of 92oct when i got to the shop. Then I was experiencing belt slip out of nowhere, so I switched to a 79" belt, that sucker is tight as hell now, no slip whatsoever.

Anyways, the car is on the dyno and it just isn't making anywhere near the power it should. We were seeing 11.5-11.8 a/f ratio, with 16* of timing. At the end the car was making 340whp, with both the base tune from Amazon, and the custom tune we were doing. Oh and even though I have the NOS kit, I have never sprayed it.

Here is where we are confused. The car is getting spark, getting plenty of fuel, plenty of air. It isn't misfiring and it is running normal. What could be wrong with the car? I want to do a compression test before I pull the blower and check it out. The blower itself isn't making any grinding or other strange noises.

I guess I'm just looking for any possible ideas of what the problem could be? Thanks in advance. It was just a huge inconvenience driving 3 hours to the tuner, spending all day there, and then driving back disappointed.


-Eric

 

[cobracide]

Bad pulley combo as a 2.90/6# would get you there with more belt wrap. You don't want it too tight. So let's have a dyno sheet and or some datalogging. Check the boost bypass. That power level is equivalent to about zero psi.

 

[Instigator99]

I have a few dyno sheets, but they are just that, sheets, no digital copies, also forgot to mention this was on a dynojet. The car seemed to drop off at around 5300-5500rpms. The 2.76/4lb lower is a tried and true combo, which is why I went with it. The belt was a pita to get on though, would too tight of a belt cause such an issue? The car does make boost and the boost bypass is working properly. Thank you though for responding.


-Eric

 

[cobracide]

Work with me here, get to a kinkos or somewhere and use a scanner. Better yet buy one they are cheap. It's one of those things you rarely use but when you need one....

Well how much boost? Without any data it's really just a guessing game.

 

[03Cobrra]

A friend of mine had a problem like that and it turned out his motor was rebuilt by the previous owner and the cams were timed wrong. He was never told about the motor being rebuilt before he bought it...the guy just told him it needed to be tuned. The car ran and sounded fine but never made any power on the dyno and felt slow on the street. He tried everything from different tuners to swapping blowers, compression test etc. Finally he gave in and tore the motor down to find the cams were off.

 

[cobracide]

I guess the next question would be has the engine been cracked open(worked on)?

 

[Brutal Metal]

Ask the Dyno owner to check the rollers, sometimes pressure builds up and needs to be released, it's happened to ours before, it's like running a HEAVILY weighted Mustang Dyno! One day my car lost 140 RWHP do to this malfunction. How does it feel on the street? you can SURELY tell the difference between 340 and 500+ HP!

 

[Instigator99]

The car feels faster in the lower rpms but it seems to kind of die down if I keep in it. I ran it at the track and got a personal best for my 60' but was 3/10ths slower than when I just had the upper. The car was bone stock when I bought it, and no engine work has been done to it. I would try to get a copy of the dyno chart up but unfortunately it's past 11pm here and I need to leave town right away in the morning for a few days.


-Eric

 

[AmazonTuning]

datalogs are needed..anything without them are speculation..surely your tuner was basing his work on datalogs from the dyno runs..he should be able to look at them and see exactly what is going on within the parameters..diagnose and adjust accordingly

 

[UptonMustang]

Sorry to hear about the dissappointing trip to Watertown man. Hopefully, you can get her straight soon. Aren't you running a 100mm idler, too? We have almost an identical setup and I haven't had mine chirp the belt even once. Let me know if I can help. My garage is always open, and the beers always cold.

 

[TRBO VNM]

One problem is the timing. 16* is very low. I used to run 19* on my street tune with 93 octane and some people said that was low and ran 20-21*.

Granted, that won't gain you 140+ rwhp though. There is definitely something else going on.

 

[Brutal Metal]

Sorry to hear about the dissappointing trip to Watertown man. Hopefully, you can get her straight soon. Aren't you running a 100mm idler, too? We have almost an identical setup and I haven't had mine chirp the belt even once. Let me know if I can help. My garage is always open, and the beers always cold.

That's a Nice Sig you got there, Sweet Parts!:rockon:

 

[UptonMustang]

That's a Nice Sig you got there, Sweet Parts!:rockon:

Much obliged:beer: