Just got the Jeep home. Impressions on 25 mile hwy/city driving... at idle/part-throttle/cruise, it runs and sounds stock. Drivability is excellent...OEM-like. Cannot tell there are headers on the car. Good for some (me), but bad for others who might want noise. I went with Stainless Works headers + catted mid-pipes, and left the stock OEM mufflers/resonators. It may be a little louder, but not noticeable to someone who thinks the vehicle is stock.
Unloaded the OEM parts and took it for a more spirited spin. Did two 0-60 launches on the same road where I have previously tested at 4.3 seconds in 55^F air. Today the air temp is about the same, didn't check baro pressure, but it is a fair comparison based on my experience. 0-60 in 3.8 seconds now. I think that is pretty respectable. Not barnstorming, but should be good for high-11s in the 1/4. I can tell that the Arrington tune is very conservative as far as TM on upshifts. Even in S mode with the trans, it does not hit quite as hard as OEM. It's not horrible, but having some experience with auto trans performance vehicles, I can tell it is there. Maybe that is something I can control with the Diablosport Trinity tuner... but I will need some input from Arrington. There's a reason they have it this way, and I really have no interest in scattering my transmission with 1300 miles on the clock. :smile2:
As far as exhaust note at WOT, it is a little louder than stock, but really didn't change the note/tone of the exhaust at all that I can tell. Granted, I've only owned the truck for 2 months and put 1300 miles on it, so I'm not going to be as dialed into the vehicle as someone who has had their vehicle longer. But there is no drone at cruise at any rpm that I can perceive.
Sounds like you are well satisfied...a 3.8 0-60 is very respectable...congrats!
Seems like Arrington has cleaned up their act. Over the past year I have been reading positive posts like yours around all the Mopar forums...2 years ago the forums were full of negative posts regarding Arrington.....my arse is still sore from my screwing they gave me 3 years ago..,,glad to here that has maybe changed...they are capable and have the ability to build great engines..
well, I'm extremely sorry to hear that. Being new to this platform, I really had no idea. My trusted local installer/tuner (primarily does GM stuff) has done some work with them before, so I had a go-between on that, and didn't deal with them directly at all. We'll see what happens if there are issues down the road, where some follow up is needed.
Most of the past issues were service related. Arrington builds a quality product. The 426 stoker I have in my 2013 Challenger has 13,000 miles and 3 years on it and has been down quarter mile tracks hundreds of times with no issues.
Most of the issues including mine were follow up service....they sold me a solid built engine but the tune they had for it wouldn't keep the engine running. At the time there were no tuners like Diablo for 2nd generation Hemis. Arrington had their own tuner which was limited in what it could do.
Fortunately AJ Berge (Hemituner) contacted me and long story short the car is everything I had hoped for. N/A all motor it runs low 11s.
I wouldn't worry about using them for your SC. Like I mentioned I have only read positive posts about them over the last year. They had a big shake up and it looks like they are back in the groove again. I would say you will be happy for a long time with your build..:smile2:
True...which is a big reason I went with it. I've run several Maggie blowers over the years, and have one on my '12 Vette. I'm not concerned with the blower...but the tuning is another story.
The shop I used does not have an AWD dyno, so I'm sorry...no numbers. It was tuned on the street. I may run it down to the local GTR shop and put it on their dyno for grins.
Completely stock internals/heads/cam. I'm not trying to break records, and really trying to stay within the threshold of strength of the stock driveline. As you can see in the pics, I have the stock airbox and airbridge on it. Did install a catchcan and LT headers...headers may have been overkill on a low-boost app. But they can't hurt. Yes, install + blower put me ~$8k.
Don't know exact boost, but it is low boost for sure. The kit says 6psi on a stock motor. Given I added headers, experience tells me I am making slightly less boost than what the kit is advertised for. This was a simple bolt-on-and-go with the packaged kit from Arrington. There are guys who are making more power than I am with a blower without issues. The key is the tune, and making sure there is plenty of fuel with no lean/detonation conditions. I'm going to make an educated guess that this setup is _extremely_ conservative. I can tell that they didn't put the trans tune on "kill."
I give credit to the guys who have tinkered much more than I have, and gone before me and pushed the envelope to find the limits. I believe I'm well under the limit with this kit, but still a nice bump in power and performance without killing reliability. But in all fairness...time will tell all.
You are bang on. There is no transmission tuning yet to set to 'kill'. Once you start making some more power than you are now the transmission torque management will not be your friend anymore. It will pull timing at shiftpoints and even fuel if you get it pissed off. There are a few things built into these Jeeps to protect them from guys like us...lol. Maybe Timzilla will chime in with more information on how the turbo encabulator actually works!
Good info. Just another reason I should just leave this alone at this point. Obviously tuning has gotten a lot more intricate over the years as manufacturers have done their best to thwart the efforts of hot-rodders. Used to, given various tuning devices, you could override TM and adjust it almost completely out. If there is no way on these to change it a little bit, to the point where if you add more power it gets more intrusive, then there are going to be diminishing returns. You've obviously pushed the limits and are having great success now. I don't have any desire for mine to be an R&D project, so keeping it mild is my goal.
At 6lbs or even 8lbs you are good to go as long as the tune is right. Pushing it father is when the trouble can start...your build should bring you pleasure for many miles and years..
Yep, it's a transmission software tuning issue that seems to be on the verge of being solved so until then I'm relegated to the mild daily driver as well. :nerd:
The trans mess on the 14 and up was the only reason I didn't pick one of these up. I didn't wanna wait for bill to get around it. Its a bummer for the guys who wanna push the platform. Im doing a big build and didn't want the trans to stop me. So i settled with a mint 12. Nice setup I wish u the best of luck with it.
That's the problem I'm talking about. Skip said there really isn't a way around the trans slowing ya down. Other than that everything is great about the 14 and up I'll pick one up when they figure it out I think. And keep my 12. I'm really gonna push for the 9s
C13Moridin is building a redic custom billet 8spd trans to handle his 1250rwhp and as of 11/24 is making progress it appears...seems inactive here and is posting updates on other site....just thought I would mention....
The challenge, as I've experienced and understand it, is software, not hardware related. Builder Bill is beefing up internals and line pressure but until he's solved the software issue we're not going any faster. From what I've read from Bill, HP70s and HP90s will be capable of handling the same amount torque based upon input shaft strength although the transmissions are physically different.
Exactly that. The software is the big fly in the thigh here. Figure out the software and everything else will fallow. A billet trans sounds amazing but if the software hasn't been cracked then no dice. I encourage more people with wk2's to make some more noise in the aftermarket industry. I'm having to make a custom tt kit from scratch Wich is fine but more expensive. I think if some more guys would start requesting more mods more manufactures would start making them. There hasn't been to much effort into the new trans and software in the 14 up. And if some of the guys were to of went with a tt kit or hell even a smaller single like a 75 or 76mm instead of a Procharger they would be much happier. Not saying anything bad about any of the kits on the market. But a turbo set up is a hell of a ride when dialed in. Just saying.
he cracked the s/w, TCM completely open, set torque where ever u want, etc...proprietary direct access, no tuners...also, it's actually and 8HP base trans...
Congrats to the OP on a nice set-up.
Just like OE but better.
Most fall for the trap of going too far and mess up an already good thing.
Re. the trans:
Except for a coupla guys really pushing the envelope, the 8HP trans issues are overhyped.
I've found it to be a good trans and unless you are over 700whp, it is more than up to the job.
It always takes the aftermarket a while to get on top of these things and until someone does, lets just bag the trans and say you need a whole heap of parts.
There are a few parties close to release on tuning software for this trans as they are widely used in the industry now. So next year should certainly see this happen and make it a lot easier to sort some of the bigger builds. But for the majority out there, the stock trans and software can perform fine.
I've not yet hurt one and I have tried...
To get that kind of 0-60 time, you are easily 100rwhp more than I am. I know you are running more boost (you mentioned before you are no longer running the stock pulleys), but I'm guessing your wizard-like tuning is where the big difference is. But ... given my lack of tuning skill with these, I'm just going to have to leave it alone. (I tuned my own EFI stuff back in the '90s and early '00s, but never had enough volume work...as it is a hobby only... to invest in high $$ tuning devices or the time to learn them, so things are way more sophisticated now than my level of competence allows)
Good to see the Australian authority on all Jeeps SRT concurs on the appropriateness of the OP's choice of power adder although I'm afraid that makes me one of the trap falling majority who has gone too far and messed up an already good thing. Thanks for your 8 speed update though. I love it!
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