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Manual hellcat mods.

7K views 43 replies 11 participants last post by  16GoManGoHC 
#1 ·
I have a 2015 m6 hellcat, and my best 0-60 time is 4.7 seconds with toyo r888r’s and kw coils. My issue is I baby the car. I bought it with 800 miles, and it currently has 11,000. I haaate slipping the clutch, and dumping it leads to wheel spin.

I never take to the track, but regularly tear it up around local windy roads and light to light races.

I’d like to get my car performing better, but I DON’T want to sacrifice reliability. I’m thinking about swapping my rear end out to a 3.90, but It seems like it may not be worth it. I want to run pump gas, so I don’t know if a pulley would be wise... Are there any mods that may help me out? Any guidance is appreciated!
 
#2 ·
I have an 18 M6 WB. Still under warranty not sure if that is an issue. If not @greasy can advise you as he has a 840whp M6. If so for me Barton shifter, Fastman TB, Pedal Commander, Lowering Springs, 190° Tstat, Legmaker CAI, and biggest was 315 555r2's. More air, ability to put the power to the ground, better throttle response, and no wheel hop have made this a whole different car thus far. You can definitely get 800+WHP on a pump gas build as well.
 
#6 ·
All a pedal commander does is change how the throttle blade opens in relation to the position of the accelerator pedal. Essentially giving the illusion of more part throttle power.
Some like it. Some think its a waste.
Tuning of the electronic throttle can be done with hp tuners, so a commander would be a waste of in that instance.

Some easy mods:
Intake
skip shift elimator (can be turn off with hp tuners)

No point in modding if you don't even like using the power it comes with. IMO
 
#8 ·
All a pedal commander does is change how the throttle blade opens in relation to the position of the accelerator pedal. Essentially giving the illusion of more part throttle power.
Some like it. Some think its a waste.
Tuning of the electronic throttle can be done with hp tuners, so a commander would be a waste of in that instance.

Some easy mods:
Intake
skip shift elimator (can be turn off with hp tuners)

No point in modding if you don't even like using the power it comes with. IMO
I do like using it, I just don’t like abusing it. Giving it hell once I’m off the line is awesome. I just don’t want to oblitera
All a pedal commander does is change how the throttle blade opens in relation to the position of the accelerator pedal. Essentially giving the illusion of more part throttle power.
Some like it. Some think its a waste.
Tuning of the electronic throttle can be done with hp tuners, so a commander would be a waste of in that instance.

Some easy mods:
Intake
skip shift elimator (can be turn off with hp tuners)

No point in modding if you don't even like using the power it comes with. IMO
i love using the power it has. I just don’t like slipping the clutch to get off the line. That’s why I was looking at the differential to help make the power a little more usable for me. Ya know?
 
#7 ·
I have a 2019 M6 HC with a 7 year B2B extended warranty and beat the living shit out of. You cannot take this thing with you so enjoy it as designed. FWIW, I set money aside every month for a new clutch because that day is going to come.

My best 0-60 on the stock summer tires is 3.2s. My only time at the track on a drag radial netted a 1.9 60'. I need more seat time to improve the launch.

More gearing will aid in getting the car moving easier. These cars would need 4.something from the factory, with a proper 5th and 6th gear for highway cruising if it were drag-only; but they aren't. They are track ready, 200mph capable, and great GT cars. One. Big. Compromise.

Mods?
Barton. Clutch delay valve delete. Take weight out of the car. The difference in driving the car loaded with my whole family onboard (wife, kids, car seats, full tank) and driving the gutted (seats out, drag pack, sway bar off, 1/4 tank of gas) is immense.

But mostly it needs the driver mod.
 
#12 ·
Not sure if the 3.90 would do much for launching the car but it does make it a bit more driveable. You can still run pump gas with a 2.85 pulley but you may run into warranty issues if you break something.
 
#15 ·
If you worry about 0-60 performance and yours already stinks then adding a pulley and making more power will not cure the problem....it will only magnify it. The best 0-60 I’ve managed with my car so far is a 4.2 and that is slipping the clutch/feathering the throttle on R888R’s. Now I haven’t practiced a ton, but I for sure need to practice more as there is more in it, but it is tough to do with this much power on tap and a banger car. That is part of the fun though!
 
#20 ·
A lower gear Tranzilla is the way to go. I run a 2.98 first, 2.10 second, 1.43 third, 1.0 fourth, .85 fifth, .63 Sixth its a bit steep on the street but at the track on a 315/50-17 is perfect. I pull about .85G sometimes 1G on the street with the 315/35-20 Nitto NT05R with a best 11.2 street 1/4, no more slipping the clutch, now it’s all in throttle control on the street. I run a 2.85 with a massaged blower and other goodies. At the track it’s dump the clutch and roll the throttle to the floor, the car normally runs 10.6-10.8 but had 1 fluke 9.998 pass on a super sticky competition prepped track, launched hard and power shifted ever gear perfectly. But if I could spend my money all over again I’d buy a Redeye.
Took 2 summers to get here and a bit of cash, going fast with a M6 is easy, being quick isn’t, being consistent about impossible without ALLOT of practice. BTW, I’m still on my original stock clutch, have 2 new ones on the shelf though waiting for the day but so far 13,500 miles and a bunch of street and dozens of track passes and still going strong.
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#26 ·
@16GoManGoHC And all that on a stock clutch! Amazing. Did you do a driveshaft upgrade? I forget.
 
#28 ·
Yea, still original clutch. Yes has driveline upgrades as well. Wiles DS, DSS Stage 5 Axel’s, DS hoop, P4D Brace, BMR lower trailing arms (AAD type 3 pc Wheel Hop eliminator kit in waiting to install) I have a new OEM clutch PP setup and a McCleod RXT1200HD one as well and when the time comes original gives up the ghost I’m mixed which one is going in??? I like the stock it grabs just hard enough, the RTX’s just grab instantly and a bit hard for smooth no shift feel (jerk) street driving but may net higher G’s and lower 60’ at the track
 
#39 ·
Right. Scratch govern out. I meant to my understanding it is limited due to drag at 199. But my thinking is if I’m hitting 199 at a higher rpm than factory, then that mph may increase? But is that strain on the engine asking for problems?

I’m at a high elevation, so I am at a disadvantage for power, so I’m just brain storming reliable performance increases!
 
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