Hellcat action!

[04blackgmc]

Ok here is some good info we have developed of before and after on the 2015 hellcat A8 model
Bone stock the best pull was
614/588
And modified was
760/745
+146 hp
+157 tq
Modifications are as follows
Craven Performance & Off-Road LLC CAI
Upper pulley combo 13.5-14 PSI
Long tube headers
Meth system
Custom calibration with HP Tuners
Catch can system

METCO MOTORSPORTS
American Racing Headers

[04blackgmc]

This pass was on the smaller pulley which actually made less power but more Tq and a 50 shot.

https://www.youtube.com/watch?v=mrcCdS8NTWA

[SultanHassanMasTuning]

thats great work

[RonSSnova]

Nice! We have one in the shop now.
Any clues on improving the stock tune?
I've heard yes you can and no you can't.....,

Ron

[Monzsta]

On the stock Hellcats I've seen there's quite a bit of melted belt rubber slung around. I wonder how the smaller pulley does in regard to belt slip.

[04blackgmc]

On the stock Hellcats I've seen there's quite a bit of melted belt rubber slung around. I wonder how the smaller pulley does in regard to belt slip.

Seen zero far after numerous pulls on different pulley combos on the dyno and track.

I never messed with it bone stock. I'm sure there is gains to be had.

[GHuggins]

Metco designed the pulleys, doubt you'll have any issues. Surprised she didn't let you play with her hellcat. She had just put 100+ miles on it when it was at the half mile shoot out... Think they had picked it up the day prior just for designing these pulleys...

Speaking of which, did you have to pull the blower snout off then press the pulley off or were you able to do it in the car?

We've had a "shop" hellcat now for 2 months with I guess the rarer 6sp manual and they still haven't decided whether they want to "experiment" on it? It put down 681 to the rear wheels stock. Very impressive

[Monzsta]

Are the manual cars normally putting that much more to the wheels than the auto? I took for granted the 8spd would be way more efficient. Maybe the converter won't lock at WOT.

[04blackgmc]

I know ours did 614 and the tuning schools on their mustang dyno as well did 618.
Both a8s.

Yea metco designed the pulleys and we did the hub machining and modification to make it all work.

Yea pulleys swap can be on car with this combo all you have to do is remove the upper hose and move it out of the way.

[GHuggins]

From what I've been seeing on line, these have been putting down somewhere around 650 with the auto's to the rear wheels...

http://www.hptuners.com/forum/showth...lcat-Unleashed

I think it just depends on how the testing is being done. Is it hot, already had a few pulls? Is a "progressive" load being applied to the dyno durring the pull. We've found if you don't do this with "ANY" boosted application, you never get accurate fuel, boost buildup or power and torque numbers which leads to the notorious "if it's dyno tuned, it won't be right and will blow up on the street attitude and justly results". Try it sometime while datalogging boost and knock With the bigger boost setups you'll probably find your only making right around 2 lbs less boost without the "simulated road load"... So when it's on the road and really pulling, she can go boom with the fueling and timing being off. I've seen this cause right around a 20 to 30 hp difference and HUGE differences in wot fueling due to the aforementioned reasons... Can be very scary when you get some cars in that have been "dyno" tuned and you see just how lean they're actually running on the street with the aerodynamics and weight of the car coming into the equation. If you have a new dynojet load bearing dyno, it should have these vehicles "load variables" already plugged into them. All you have to do is activate the settings... I have and use one of the very early prototypes of these equations on the older dynojet hardware... Granted, that is if your not doing this.

If your not doing this, and you have a dynojet dyno, I can try to email you this Shane if you like. Just let me know... Not sure if you can email it since it is a pretty big file, but I can try...

[04blackgmc]

I use a loaded mustang dyno...

[GHuggins]

Really, I know the mustangs are typically really close to the dynojets when they're loaded. Very interresting... I assume iat's and ect were above the usual operating temps?

Guess the A8's do sap a decent amount of power, but I've seen them in the 640 to 650 range time and time again, so who knows... Was the red key turned all the way up in the dash to full power because they themselves were changeable via driver controls? That's really the only other thing I can think of.

[04blackgmc]

Most all the time mustang dynos will give lower numbers.

Like i said this one was t 614 bone stock on our mustang dyno. Alex down at thee tuning school seen 618 stock with theirs on a mustang dyno as well.

Yes the red key was used lol.
I don't try to get wrapped up in numbers but the before and after gains are what tells the story.

614/588
And modified was
760/745
+146 hp
+157 tq

[doc350]

I don't try to get wrapped up in before and after but gains are what tells the story.

Man I wish more people thought this way, kudos to you sir.

I haven't had the pleasure of working with a Hellcat yet, but I do have a couple customers with them.

Is there anything to be gained with adjusting the "bypass valve"? Is that even possible? It seems like you could do some neat stuff with it if the controls are there, since it is essentially another throttle body.

[04blackgmc]

Man I wish more people thought this way, kudos to you sir.

I haven't had the pleasure of working with a Hellcat yet, but I do have a couple customers with them.

Is there anything to be gained with adjusting the "bypass valve"? Is that even possible? It seems like you could do some neat stuff with it if the controls are there, since it is essentially another throttle body.

I had to correct that sentence poor grammar on my part haahah.

I have not yet messed with and not seen a reason to. The main thing i hate so far is trying to get past the 6,250-6300 RPM limit and throttle delay below 3,500 RPMS. Even Alex at the tuning school cant get past the throttle delay. The RPM limit must be in the TCM or something that isn't seen yet. I've raised the limiters I can access and no change so far.

[06300CSRT8]

RPM limit has two, engine (PCM) and transmission (TCM). Engine can be set anywhere from the transmission limit and below but not higher, itll go into limp mode. Not sure if any of the major players in the hemi world have begun to tackle the new TCMs for the 8speeds.

Throttle delay not sure on, since I am sure you have already taken a stab at the tip in timing? There is a table that handles throttle voltage change versus timing retard.

Also you may be facing a mechanical delay, with the bypass closing slowly. With the higher boost, maybe its struggling to close fast enough.

[04blackgmc]

RPM limit has two, engine (PCM) and transmission (TCM). Engine can be set anywhere from the transmission limit and below but not higher, itll go into limp mode. Not sure if any of the major players in the hemi world have begun to tackle the new TCMs for the 8speeds.

Throttle delay not sure on, since I am sure you have already taken a stab at the tip in timing? There is a table that handles throttle voltage change versus timing retard.

Also you may be facing a mechanical delay, with the bypass closing slowly. With the higher boost, maybe its struggling to close fast enough.

I have tried about 10 different tables and none have changed the delay :/

[GHuggins]

Most all the time mustang dynos will give lower numbers.

Like i said this one was t 614 bone stock on our mustang dyno. Alex down at thee tuning school seen 618 stock with theirs on a mustang dyno as well.

Yes the red key was used lol.
I don't try to get wrapped up in numbers but the before and after gains are what tells the story.

614/588
And modified was
760/745
+146 hp
+157 tq

All too true... Very nice gains as well. Now if we don't sell our hellcat, maybe I can get to play with ours...

[[email protected]]

04blackgmc - Thanks for posting this info! I have several Hellcat customers wanting to go a similar route once they can access a spare PCM.
BTW - Our dyno testing results (Mustang MD500 AWD) on two different Hellcats yielded similar results to yours. One Hellcat made 614whp, the second made 617whp.

Please keep us updated on the rev limit issue. As stated above it is most likely TCM controlled (similar to all previous year DCX vehicles).

[04blackgmc]

04blackgmc - Thanks for posting this info! I have several Hellcat customers wanting to go a similar route once they can access a spare PCM.
BTW - Our dyno testing results (Mustang MD500 AWD) on two different Hellcats yielded similar results to yours. One Hellcat made 614whp, the second made 617whp.

Please keep us updated on the rev limit issue. As stated above it is most likely TCM controlled (similar to all previous year DCX vehicles).

Sounds like the dyno at work is pretty on par then to me.

Yea I'm hoping once some cooler weather rolls in we can get that 9 no issue.