Having pinging issues with SCT Xcal II

astronut1885

Founding Member
Jan 31, 2002
1,899
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39
Assonet, MA
Hey guys. I had a local shop load some generic 87,91, and 93 tunes for a factory 04 onto my Xcal II. Now, when I fill the tank with 93 Octane Sonoco, and load the 93 tune, it pings below 2k and over 4k RPM. I backed 6* timing out of the >2k rpms with no improvement, fattened up WOT 8% richer with no improvement, and backed 4* out of 4-8k, again with no improvement in pinging. I can run the 91 octane tune with no problems with 93 in the tank, but the car smells rich as crap and gets lousy mileage. I know the plugs are new and gapped right, and I run Lucas fuel system treatment regularly with oil changes. What are my options other than dynotuning? I'm getting my blower in by mid summer, so I'm not going to pay for dyno time for my current setup. Any ideas are welcome.
 
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isn't worth the high gas prices?
ISn't the 93 tune 15HP? so with bolt ons (plenum/tb, H pipe, catback, etc) possibly 20 HP?

That would mean if you only gained 10 HP from bolt ons- you are at 270HP, plus the tune you would have 290HP. Seems worth it to me? you'd have the same HP as the new 3v
 
isn't worth the high gas prices?
ISn't the 93 tune 15HP? so with bolt ons (plenum/tb, H pipe, catback, etc) possibly 20 HP?

That would mean if you only gained 10 HP from bolt ons- you are at 270HP, plus the tune you would have 290HP. Seems worth it to me? you'd have the same HP as the new 3v

Just remember that you are using crank hp numbers when you say 290hp. My 99GT (75mm tb,CAI,Mac o/r prochamber,Bassani catback,FRPP 4.10 gears and a 93 xcal II tune) made around 230hp to the rear wheels. Which when you figure 20% loss due to drivetrain puts me at 290hp at the crank.
I'd say just run the 91 tune as 5hp give or take will not make too much difference to the SOTP performance of your car, and wait till you get that whiner installed over the summer and get it custom tuned.
 
I understand it's crank- but still..you can say 'i'm making about 300HP' The 3 valves are also just '300 HP at the crank' but they run 13s from the factory.

Yeah but saying you make 300hp will lead most people who know anything about cars to believe that is rwhp. I just say that cause you will be considered a real NEWB!!!! if someone asks. Not trying to flame you but I just think that hp numbers should be given as real usable hp. JMHO.
BTW I run 14.1 at 100mph in the 1/4.
 
Only way to know is if its on a dyno. i best most people don't even know what their car runs to the wheel bone stock. I think people using big words and guessing "usable" HP are the real noobs
Most people who "know about cars" must not know that Horse power implies Horse power at the crank. Wheel horse power implies horse power at the wheel. When you read a magazine, the term Horse power implies at the crank. When magazine authors write Horse power- they mean horse power at the crank- unless they specifically state- RWHP.
 
Only way to know is if its on a dyno. i best most people don't even know what their car runs to the wheel bone stock. I think people using big words and guessing "usable" HP are the real noobs
Most people who "know about cars" must not know that Horse power implies Horse power at the crank. Wheel horse power implies horse power at the wheel. When you read a magazine, the term Horse power implies at the crank. When magazine authors write Horse power- they mean horse power at the crank- unless they specifically state- RWHP.

Uhhh no...

No one cares about crank hp unless its on stock car and then people still want to know what its putting to the rear wheels if its a performance car. Plus when car people talk they talk rwhp anyways its some what implied even if you say hp and not rwhp.

No one brags that their car is making 300 hp at the crank, trust me you won't impress anyone with that. Plus you're still guessing on crank power because you really don't know how much your picking up from each mod.
 
I put down 258 at the wheels. Thats the important number.

Crank numbers are good to have if you want to figure out what % of your power the rest of the drivetrain is sucking up.

Say I make 300hp at the crank, and im putting down 250 rwhp... 300 x .15% (average 5 speed figure) drivetrain loss should put it around 255 rwhp... so 250 is close in proximity to that, and other variables will factor in because 15% drivetrain loss wont be a true number for every car.

RWHP is what you utilize though.

Even more important, each dyno is different. Two rarley will spit out the same numbers, so there is a possiblity for a fluxuation between dynos for sure.

Everyone should remember they are an amazing tuning tool, and HP numbers dont mean squat if you cant put the power to the ground, cant drive, excetera.

Anybody can put down high HP numbers and be a dyno queen, but the real testament to me is what your timeslips are reading...

Any Joe Schmoe can go buy a Shelby GT-500 and put down 430 rwhp. That same Joe Schmoe might only click off a 13.5 at the track cause he cant drive worth a squat. Put Racer-X in the seat of the same car and watch him click off consistant 12.3's.
 
I put down 258 at the wheels. Thats the important number.

Crank numbers are good to have if you want to figure out what % of your power the rest of the drivetrain is sucking up.

Say I make 300hp at the crank, and im putting down 250 rwhp... 300 x .15% (average 5 speed figure) drivetrain loss should put it around 255 rwhp... so 250 is close in proximity to that, and other variables will factor in because 15% drivetrain loss wont be a true number for every car.

RWHP is what you utilize though.

Even more important, each dyno is different. Two rarley will spit out the same numbers, so there is a possiblity for a fluxuation between dynos for sure.

Everyone should remember they are an amazing tuning tool, and HP numbers dont mean squat if you cant put the power to the ground, cant drive, excetera.

Anybody can put down high HP numbers and be a dyno queen, but the real testament to me is what your timeslips are reading...

Any Joe Schmoe can go buy a Shelby GT-500 and put down 430 rwhp. That same Joe Schmoe might only click off a 13.5 at the track cause he cant drive worth a squat. Put Racer-X in the seat of the same car and watch him click off consistant 12.3's.

:stupid: Very true.
 
So... who's ready for the weird story?? I fixed it as far as I can tell.

Anyway, I'm out in the car, playing with the tune and beating the snot out of it on back roads to see if it will ping. And it always did. no matter what. I called my local shop (who loaded the generic tunes) and he said that my stock gears weren't helping because they made the lag and load on the motor worse. He also said my CAI could be leaning out the motor just a tad, but enough to screw up a high-po tune. Sounds reasonable to me. But I figured that for the immediate time, I still needed the car to run. I took another blast on another set of adjustments, and noticed a boatload of white smoke coming out behind the car. I thought I was toast, like a blown head gasket. I get home, and there's lots of tranny fluid under the car, and the drain plug in the bottom is backed out like 3/4 of the way. Since I had no idea how much fluid was left, and since I had never done one in the year I've had the car, I did a fluid change with Mobil 1 synthetic Mercon. Now, here's where it gets weird. I took the car out, no pinging. And it felt a crapload more responsive and fast. I turned the timing back to what the tune was supposed to be set at, in all RPM bands, and no ping. Reduced the WOT fuel richness to it's proper setting, and still no ping. My car is like a freak now. Sounds bad, has more zip than ever, and I don't think I did a thing. Only thing I can possibly guess at is that the tranny fluid was old and had minimal viscosity left, which is why it was getting so hot it was blowing around the drain plug ( the tranny was hot and there was foamy tranny fluid under the shifter too). After enough either cooked or left, the tranny wasn't getting lubed, and was basically getting bind and hosing up my whole driveline. I know this sounds completely nuts, but it's all I got. Timing/fuel problem gone after a tranny fluid change...:jaw: