What's my problem?

[clipsekid99]

Hey guys, what's up? I have had a few things happen lately concerning the car, and a question arises..... why aren't I making more hp/tq.?

Ok, here's the story. My local tuner shop just got their awd dyno, so I jumped on that thing as fast as I could lol. First run, I was extremely disappointed with a result of about 166 hp and 192 tq to the wheels on a AWD Mustang Dyno. On top of this poor result, the chart showed I was running extremely rich throughout the powerband, which was causing me to loose power, and go through a tank of gas every week.

So, I took the shop owner's advice and ordered an Apexi SAFC 2. Ya, ya, I know DSMLink is the way to go, but I'm not really in the position to search for a 95 ecu and buy the program and stuff, so please don't knock me on that lol. So, skip a few days later, the SAFC is installed along with brand new Mobil 1 oil change, brand new NGK BPR7ES plugs, and a new starter (old one grinded on startup). The guy tuned it fairly well. Car feels a ton more smoother, and he straightened out the a/f curve. Only thing is that I'm still not making much power! Final dyno after tuning is about 172 hp and 189 tq.

Now, he did say that the graphs definatley show that boost keeps falling off around 4500 rpm, which is cause I'm still on t25. Also, it shows that my boost is spiking to around 20 psi! Why would it be doing that without a boost controller? I still have the BCS connected, and have not done anything to tamper with boost control.

Please help me!
Thanks guys

EDIT: Oh ya, I do have the printouts of the dyno runs I can take a pic of and post if needed. And my current mods are in my sig, or on my website.

EDIT 2: LOL, I forgot to tell you guys, when on the final dyno run for tuning, I guess the guy didn't torque down the straps holding the car down enough, and the buckle on the strap got jammed into the radiator from the vibrations and it craked the radiator and coolent was everywhere! But, since it was the shops fault, I got a brand new radiator overnighted and installed FOR FREE! Woooo lol.

[AbsoluteGTR]

That seems pretty low....the car should be in the 210+ horsepower range, right?!

Make sure there are no boost leaks, that could be why you are at 20psi, the computer might be trying to compensate for the lack of pressure (at stock boost which is like 12/13 psi) and it might be upping the boost so it can get the sufficient power that it is supposed to be getting!

Good luck man

PS: That sucks about the radiator, but hey atleast you wont have to change it for along time! Unless it happens again! LOL

[rckrz6]

Originally Posted by AbsoluteGTR

That seems pretty low....the car should be in the 210+ horsepower range, right?!

Make sure there are no boost leaks, that could be why you are at 20psi, the computer might be trying to compensate for the lack of pressure (at stock boost which is like 12/13 psi) and it might be upping the boost so it can get the sufficient power that it is supposed to be getting!

Good luck man

PS: That sucks about the radiator, but hey atleast you wont have to change it for along time! Unless it happens again! LOL

i think hes talking about HP to the wheels not at the crank thats about 20% loss... hes running maybe abit low still but not terible low like his first test

[l_eclipse_l]

Originally Posted by rckrz6

hes running maybe abit low still but not terible low like his first test

How is a gain of 6 hp AFTER tuning make it much different? He should be in the 190-200 hp to the wheels category with his mods. I would guess and say maybe the turbo is dying? Dosn't seem like it should be dropping off at boost so early, but I'm not exactly sure, so don't take my post too seriously. Just brainstorming.

Couldn't these guys at this shop tell you anything to look for as to why your numbers might be off? Also why would your torque go down after tuning? Weird.

[clipsekid99]

I just went ahead and took pics of the dyno sheets....

Red line shows a/f
Green line shows hp
Blue line shows tq

Before tuning:



After tuning:



You can see that the red line is much more stable now, and it following the 11.7 line, which he said would be good. I'm lost here guys!

[crunchymilk55]

11.7 is WAY too lean for a pump gas tune. I would only run that on race gas. I wasn't there for the tune, but it seems like this guy doesn't know DSM's very well. It's hard to tell, but by looking at that picture and my shitty vision it seems to me like you're actually running a 12.x a/f at around 4k rpm. Again, WAY too lean man for pump gas. Was this with a wideband?

Also, your power is about right. Your car is old, so say it's making around 200 or so at the crank if it were stock. 20% loss puts you at 160hp to the wheels. Now, add in your mods (which are minimal at this point). in fact, the only power mods you have right now are the intercooler pipes, catback exhaust, and a filter. Add to this a decent tune (far too lean IMO), and the power is about right.

If I were you, I would add some fuel across the board and save your motor. Also, how's your timing doing? I assume you have a datalogger. Without seeing your knock/timing, the tune is pretty useless.

Post the datalog with that tune so I can see what's really up.

[clipsekid99]

I'm under the impression that this guy knows quite a bit about cars, but I'm not sure how much is on DSMs. The shop car is an Evo which is running some pretty low times at the track.

I don't know if it is a wideband or not. All he hooks up to the car is a thing to tap for rpm signal, and a little probe thing he sticks in the muffler tip.

I don't have a datalogger or anything, just the afc. I'm a little strapped for cash. I don't really trust myself doing any tuning by myself

[Bodack]

Well I'll go ahead and say what everybody is about to. Go get a datalogger! www.datalogger.com I think it's $125 for software and cables and then $25 on amazon.com for a used Palm. You'll need this to see what's going on throughout the RPM range. Tuning without a datalogger is like pissing with your eyes closed. You just kinda go for it and hope you don't miss.

[clipsekid99]

So does anyone have any other ideas on what it could be without me having any datalogs? Could it be like bad compression, boost leak, or any things like that?

[saturnspeed_12]

well to me that seems fine. i found a place where these guys had a 98 gsx with quite a few mods made like 210hp and around 200 lbs/ft. see the the other problem with the gsx's is the clutch and hydraulic system. those items are limited to how much power you can make so you dont destroy your driveline and especially trying to burnout to make harsh takeoffs. the overall clutch, from what i hear, is soft and is made specifically for the stock set up and so that they wouldnt get many warranty claims for broken pieces on the awds.