Tuning And Max Power Pool

[themush 6]

With the new motor, and new ZF8 speed, rated at 900nm/tq, we are going to see some failures as people start modding and testing the limits of the new powertrain.

A SRT video said they used a new upgraded ZF transmission. Did they mean the transmission itsself is an upgrade from the POS NAG-1 (obviously it is)..or did they upgrade the ZF to handle more power.

900nm is about 663ftlb of torque My guess is they had to upgrade the clutches from the get go. Thats too close to max out straight out of the box.

So anyone want to make some guess on

Max boost hellcat can handle

Max HP helllcat can handle

Max HP/TQ the ZF8 spd can handle

How long it takes Diablosport et.al to crack into tuning.

Who will be the first person to pull the blower off, put a 6.1/6.4 intake manifold on it and twin turbo it.

They didnt leave much room on the table with the 392 and nag1 for upgrading with bolt ons. Hopefully thats not the case here

[toofart 148]

With the new motor, and new ZF8 speed, rated at 900nm/tq, we are going to see some failures as people start modding and testing the limits of the new powertrain.

A SRT video said they used a new upgraded ZF transmission. Did they mean the transmission itsself is an upgrade from the POS NAG-1 (obviously it is)..or did they upgrade the ZF to handle more power.

900nm is about 663ftlb of torque My guess is they had to upgrade the clutches from the get go. Thats too close to max out straight out of the box.

ZF makes the 8HP45 (v6 models), 8HP70 (Trucks, Hemis) and the 8HP90. They simply went with the 8HP90, they didn't upgrade a thing from the ZF design.

It does mean that the trans it maxed out though, so anyone adding power is living on borrowed time. Mind you, the Nag1 is designed for 428 lb.ft of torque, so "maxed out" is only relative to a 200,000 mile lifespan.

[themush 6]

Damn, thats sad. If they just used a off the shelf 8hp90, like you said, its going to be about as useful as the Nag1. Im sure Bill or others will come up with a solution. I wonder if it will be possible to put the 8HP90 in place of a Nag1 in 06-2014 models? with a new TCM. Im sure it will physically fit, worst case changing drive shaft as well. Although, im betting its pretty damn close to the same physical size as the Nag1 since they used the lower tq models on cars that also had the nag1.

That would be a nice upgrade to the nag1 for people with moderate power levels like myself.

[sharkcohen 60]

HP90 for my 2012, please.

[Speedy 247]

Well, I wouldn't be so quick to say it's maxed out. The shift program will have a lot to do with it as well. If it's really banging gears like a 1970 four speed like they say that'll go a long way to making the trans last. All the soft shifting, cruise to the mall comfort is what kills a trans with the slipping clutches and heat. Also, I'm pretty sure it gets a trans cooler as well. If not add one and it'll help a lot.

We don't know what kind of piston material they used do we? Everything else sounds pretty beefy in the engine and I'd think it easily good for 900HP (crank) or a little over 800 to the tire. Not sure if the trans could handle that much though.

With some tuning the stock blower can probably make 14-15psi which would be a good sweet spot for this thing and keep it reliable.

It took Diablo a couple years to crack the new GPEC stuff and it's still not complete. I'd expect the same for this, but honestly over 600RWHP is a lot to play with on the street as is.

[themush 6]

i dont know much about tuning MAF..but dont you have to retune even for something as simple as a "cold air intake" ? And dont most intakes with a MAF have to have a very precise MAF housing made into the intake?

[Speedy 247]

You're confusing MAP and MAF. MAF will self tune quite a bit to changes. MAP will not.

[themush 6]

oh, ok. So on a MAF it can compensate for fuel to some degree as well? Could you slap on say a 50-100 shot of nitrous and the MAF system adjust fueling based on MAF readings?

[Speedy 247]

The MAF (mass air flow) sensor responds to increased air flow and adjusts fuel, and I think timing, to compensate. I bolted a supercharger to my 4Runner with NO tune and it added plenty of fuel to compensate for the extra air. It wasn't until I went to a 10psi pulley I needed extra.

[themush 6]

Dang, so something like a pulley change out or shot of nitrous and you might not even need a tune. I see the hellcat runs off wideband, so i reckon if you ran a fuel pressure monitor/guage and kept an eye on AFR you could maybe get away without a new tune.

Speedy, you might find this interesting

Jay leno had a video of him demo'ing the hellcat, and it was pointed out how much work they put into cooling.

Tim mentions the intake air temp reading on the center display..and it shows up at 172 while they are sitting there at idle. I dont remember what you were logging when you were doing all that intake temp testing. But 172 seems rediculously high.

[toofart 148]

I went from 6 psi with cats to 10 psi without and didn't touch my tune at all.

MAF is overrated.

[Speedy 247]

Dang, so something like a pulley change out or shot of nitrous and you might not even need a tune. I see the hellcat runs off wideband, so i reckon if you ran a fuel pressure monitor/guage and kept an eye on AFR you could maybe get away without a new tune.

Speedy, you might find this interesting

Jay leno had a video of him demo'ing the hellcat, and it was pointed out how much work they put into cooling.

Tim mentions the intake air temp reading on the center display..and it shows up at 172 while they are sitting there at idle. I dont remember what you were logging when you were doing all that intake temp testing. But 172 seems rediculously high.

The nitrous would be iffy, but definitely a smaller pulley shouldn't be an issue within reason. The idle IAT at 172° was supposedly in 90° ambient air. That is HOT for just idling, but they could have been sitting there for a half hour or something, who knows.

I went from 6 psi with cats to 10 psi without and didn't touch my tune at all.

MAF is overrated.

Your tune was scaled for it. Had it not been, no bueno.

[themush 6]

Well sweet. Like you pointed out though. They already dyno'd it and according to the article, stating that the power is under rated as it is. But lets say a pulley for just even 2-4 more psi.700-750rwhp-ish. Thats already plenty for street. Assuming the transmission can hold up to that for an extended period of time. For the every day guy, excluding the hard core track guys here..what else could you really want to do to this thing power-wise. Honestly, I think if i got one, which im hoping to get the Charger, Id be pretty content with just a pulley swap.

Just having it tuned for part throttle is exciting. Even though you and others say light part throttle isnt a big deal, i still try to avoid it. The 8spd seems wonderful. Put a 3.92 or 4.10 out behind that and still get decent hwy mpg.

My opinion, the hardcore track guys are gonna stay in the 5.7L/6.1L/6.4L game. Already proven formulas and results and research and products for those motors.

I think it will be a few years before there are any major developements off this motor. ITs not like its THAT much better of a foundation of a power plant to build a track car off of than what we already have. But it is perfect for a plug and play ready to go ass beater. And, in my opinion, both new re-designs are gorgeous. Especially the interiors.

The one thing i hate about our gen cars..again, is the part throttle issue..and you mentioned it earlier as well with the tranny. IT makes you drive like a bitch for fear of leaning out in part throttle. So the option is..drive like a bitch..possibly not good for your tranny. Or drive it WOT..which trust me, im on my 3rd transmission, is also not good for a transmission not setup for the torque. ITs hard to drive inbetween that and not live in part throttle land. 1-2psi im ok with..but if i get up around 4-6, i get a little paranoid.

[Speedy 247]

You see my thread where Mike at OST has mine richening up at PTB? No more issue there, and I never worried about it anyway with forged pistons, but Mike wanted me to test it out and it worked perfect.

http://modernmoparforum.com/topic/13902-fuel-enrichment-at-part-throttle-boost/?hl=%2Bpart+%2Bthrottle+%2Bboost

600RWHP is plenty for the street. I'd save the extra pulley for the track. I'm right at 600RWHP and easily get the car sideways just rolling in to the throttle at 80MPH.

[ChargerRob 1]

Damn, thats sad. If they just used a off the shelf 8hp90, like you said, its going to be about as useful as the Nag1. Im sure Bill or others will come up with a solution. I wonder if it will be possible to put the 8HP90 in place of a Nag1 in 06-2014 models? with a new TCM. Im sure it will physically fit, worst case changing drive shaft as well. Although, im betting its pretty damn close to the same physical size as the Nag1 since they used the lower tq models on cars that also had the nag1.

That would be a nice upgrade to the nag1 for people with moderate power levels like myself.

You can most likely convert a 2011 Charger, 300 and maybe the Challenger, but not the 2005-10 cars as the floor pans weren't design with the 8 speed in mind..

[themush 6]

They changed the floor pans? I had no idea. Damn. Nothing a hammer won't fix. Ha

Speedy. I did see that. But I thought I read in another thread that's it could easily cost 1500 worth of tuning. And yea, I'm right around 600rwhp as well. Main differences are, I don't make as much boost as you in the low rpm, and..I'm an auto. So if you go wot, you are downshifting 2-3 gears and raping the shit out of your car. Unless you drive around in autostick, which I do sometimes. I only make about 6psi down low. Which is why one of those programmable drive blowers would be bad ass!

[1FST4DR 85]

IM curious as to why you call the nag 1 a POS Its actually a pretty stout trans for most street applications. Obviously if you take it to a drag strip and add 300 HP it will take its toll. We have plenty of 500-600 rwhp cars with years of use on basically stock Nag 1's Now mind you they don't see much track time

[themush 6]

Well, the Nag-1 in a mercedes application is great im sure. Im on my 3rd transmission, and 2nd converter. Never been to the track. And i drive it relatively calm. My mom has a 2007 300C, converter went out at 70K miles. My old 300SRT the transmission started to let go at 50K on 535ish to the wheels.

I know before i purchased the car, the dealer rebuilt the transmission stock. I have the service paperwork from it. After about 6 months of ownership, my converter went out. Replaced it with a stock converter with mercedes internals. Added blue tops. Started to slip, removed blue tops and installed paramount stage 2 valve body. Now its failed and after pulling it apart, had 1 clutch left.

All my Paramount parts came in this week to rebuild it. Paramount upgrade kit, stage 2 valve body, and blue tops.

Im just not a fan of it. It shifts fast which is great. But it very clunky and seems a little unreliable in my experience. I know others have had better luck. For me, its been a POS, or an extreme weak link when modd'ing. But, its simplicity is nice, and when working correctly, it is a nice transmission. I wouldnt call it a slushbox. Ive just had bad luck personally with them.

[themush 6]

So Im gonna throw out

750rwhp max on the tranny

800rwhp max on the block/internals. Maybe a bit more with meth when tuning is available.

[Harrison@Stage6 25]

If you're paying $1500.00 for tuning you need to find another fucking tuner!

[themush 6]

If you're paying $1500.00 for tuning you need to find another fucking tuner!

I havent. I just thought I read AJ or someone say that part throttle tuning is doable, but its expensive because the amount of time it takes to get it right, and its not worth the investment if you have a forged motor. Dont hold me to that though, I read a lot of shit and it just blends together.

Also- any tuning wizards out there..how much more creative and effective can you get with tuning the hellcat versus the previous motors, since we were mostly restricted to only open and closed loop? Now, being a factory boosted car, im sure the maps will be alot more tweakable and be able to fine tune much more than just WOT and "everything else".

[Harrison@Stage6 25]

Part throttle has been doable. Its not nearly as hard as you think. The tuners won't know how much is left until they get to look at a stock file. I'm sure there's maybe a couple of degrees of timing left and that's probably it with a stock pulley. Use some race gas to get rid if whatever knock there may be.

What makes you say a proper tune isn't worth the investment if you have a forged engine? That makes no sense. What good is having a forged engine if it isn't tuned right?!?!

[themush 6]

Oh, I didnt say that, the thread i was reading said that. If i could even remember what forum it was on, id link you. But it said the cost to part throttle tune outweighed the cost of doing so if your motor is built, a little part throttle wont hurt anyways. But i know very little about the intricacies of tuning, so i just kinda soak up all info i read. I personally dont know how much part throttle boost a untuned motor can deal with. To me, it would be worth it to make sure it would never lean out. Because after having to rebuild my motor because the fucktard who owned it before me busted 4 pistons, even a $1500 tune would have saved thousands of dollars

[Speedy 247]

Lots of misconceptions here. There are several things tuned at part throttle on a boosted car, the major one being timing. Low RPM and boost can = knock if not tuned properly to reduce timing down low and feed it back in as RPMs rise. That's standard practice. Part throttle boost fueling was a simple change Mike made to mine and it required a single tweak to DFCO and that was it. It was easy for Mike to tune it and it's been perfect.

[themush 6]

Blame me for the misconceptions. Like i said, I cant even remember what forum it was on, let alone remember exactly what was said other than it was alot more work than what it might be worth (according to what i remember reading).