Bad Numbers - Chally SRT8 w/6M

[Raszaron]

Predator Part Number: Will update when I get home
Predator Revision: Will update when I get home
2009 Dodge Challenger SRT-8 (M6)

I read the thread in the announcement, and commented there, but thought I might get more attention with an actual post of the concern.

I have an 09 Challenger SRT-8 with 6spd manual w/ the following mods:
1. AFE stage2 CAI w/ heat shield
2. Jet 180 Thermostat
3. BT Oil Catch Can
4. Magnaflow high flow cats with 3" tubes
5. Magnaflow 3" Competition Catback Exhaust w/ X-pipe
6. Diablo Predator

I took it to have a CMR done, and when they ran the car the first time to get the base line the numbers where:
379whp - 371ftlbs

Conditions: OAT~78, IAT~80, RH~45%, 93octane fuel, Oil changed week prior with Mobil 0W40, 1800 miles on the odometer

The tuner then tried to do what he could and the best he pulled was:
381whp - 373ftlbs

What is up with these numbers? I don't know how knowledgable the tuner is with Hemi's (primarily tunes Corvettes and Camaros), but the shop was building a twin turbo SRT-8 Challenger.

[NickLovin]

Do you have a dyno chart of before and after? Did your overall powerband increase?

I don't give much credit to peak numbers to begin with. If your overall powerband has increased then I'm inclined to say the tune was successful and there isn't a problem...

How does it feel compared to previously?

[mikel]

.

How does it feel compared to previously?

Thats the biggest question.

Please post the dyno graphs, and get some logs to see if there is any KR present.
Did the tuner mention anything about Knock?
Did you have good quality fuel in the tank?
Was this a custom tune done with CMR or the canned tune, or adjustments made through the Predator to the canned tunes?

[Raszaron]

.

How does it feel compared to previously?

Thats the biggest question.

Please post the dyno graphs, and get some logs to see if there is any KR present.
Did the tuner mention anything about Knock?
Did you have good quality fuel in the tank?
Was this a custom tune done with CMR or the canned tune, or adjustments made through the Predator to the canned tunes?

- Compared to previously, the same, maybe a little smoother or when I rev the engine, a little more popping in the exhaust, but not much.

- When I get home I will scan and upload the Dyno sheet, but if memory serves me, the lines seemed to be relatively close to one another.

- The tuner did not mention anything about knock, he did say that the left bank was running at idle 13%, the right bank was at 17%. He tuned those to 1% and 1.5% at idle.

- I used BP 93 Octane

- I do not know if he used CMR or the canned tune, I will call them and ask what he used.

[NickLovin]

.

How does it feel compared to previously?

Thats the biggest question.

Please post the dyno graphs, and get some logs to see if there is any KR present.
Did the tuner mention anything about Knock?
Did you have good quality fuel in the tank?
Was this a custom tune done with CMR or the canned tune, or adjustments made through the Predator to the canned tunes?

- Compared to previously, the same, maybe a little smoother or when I rev the engine, a little more popping in the exhaust, but not much.

- When I get home I will scan and upload the Dyno sheet, but if memory serves me, the lines seemed to be relatively close to one another.

- The tuner did not mention anything about knock, he did say that the left bank was running at idle 13%, the right bank was at 17%. He tuned those to 1% and 1.5% at idle.

- I used BP 93 Octane

- I do not know if he used CMR or the canned tune, I will call them and ask what he used.

See what he says... Might be time to find a different tuner...

[johan]

I have seen the srt's be lower on power with lower miles on the motor, i would run it again after you have 5k miles on the odo, should make considerably more power when it has loosened up a bit.

[Raszaron]

Thanks johan, Here is the info off of my Predator (srl#241493, PCM#68004308AF). I took the car out and added ran a diagnostic, watch and record. I will try to dl it in a little bit.

[Raszaron]

Predator PN# U7135, Revision v.9r16, 2009 Challenger SRT8 M6

I have the data log on my computer and I recorded the following values:
TCYL VE MOD
Engine Runtime
Actual Spark, Base Spark, CHRG SPK ADJ, SPK ADJ, Thermal SPK
KNK Fuel Retard, LT Retard, ST Retard, Knock Sensor 1 & 2 Volts
Engine Speed

[Raszaron]

Did I put the log in correctly, and because I am not even an apprentice to tuning, what are we seeing? It appears that the knock goes crazy a few times, but settles out, as it should, when steady cruising. WOT looks to be the suspect at best, and I do have a catch can on the car. My tuner (if I should say that) did say that he only noticed 1 to 1.5 on the knock. Once again, I don't know what the range is or should be. Your help is greatly appreciated.

[Raszaron]

Is there any input on the log that I posted? Appreciate your feedback.

[johan]

That log file is corrupt, maybe try to zip it then upload it again.

[jah81592]

I have seen the srt's be lower on power with lower miles on the motor, i would run it again after you have 5k miles on the odo, should make considerably more power when it has loosened up a bit.

You got it, I had a customer come to me with only 5K on the odo, the best we could squeeze out of it was 379hp on a dynojet 224. Guys (not Mike) don't get too wrapped up with peak #'s I would focus on the power under the curve-that is where the engine will spend most of the time. On the Chally I tuned which only made 379 we picked up 20-25 hp and equal torque average through the powerband. If you look at that then the gains aren't really that bad.-j

[Raszaron]

Here is the response that I received from the tuner.


Yes I was monitoring knock retard. It was only pulling about 1-1.5 degrees, and just for a short burst. I can tell you there's not 50 hp in the tune. There's not that in pretty much any N/A tune.

I will try to upload the file after I zip it.

Thanks for the input jah81592. I am comparing the numbers of the what Diablo got on their SRT8 to that of of mine with similiar mods. Just wondering what the cause of difference is. I will also try to scan and upload the dyno graph, unfortunately it is black and white. Plus there isn't much difference between the two sets of lines.

[mikel]

Different dynos first of all, different weather, different cars....all are variables that mean you can not nor should not try to compare dyno numbers unless they are on the same dyno, on the same day....