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Discussion Starter #1 (Edited)
My Scat Pack is all stock with the A8. Last night was the first time using drag radials and I made a few mistakes. It will take a few passes to work out how the car needs to be launched. My best run was a 12.21 @113mph with a 1.73 60 foot. The DA was 1330. My worst run was a 12.70 @111.2. I did not roll through the water box. I did the burnout in the box so my DR's were still wet when I launched and the car just spun off the line. Tires were set at 20psi. I would do a 5 second burnout shifting from 1st to 2nd during the burnout. Left after the second light went off. Traction control was off and the transmission was in drive.

Our local track's last test and tune night for the season is on Friday night and the forecast is for rain. Should have bought my DRs sooner. I picked up the set recommend on this site from Summit. The MT 305/45/18 Rs with the Bravado Tributes. It was a whole lot of fun and can't wait to go back to the track.
 

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Very good but next time pull out the air filter as this will lean the rich stock tune down a bit and if you want to really pick up some time use a 50/50 mix of unleaded vp109 and with the gas you use as this alone will help timing from being pulled and the extra oxygen in the vp109 ( 6.3% ) will help with a little more hp. This always helped my srt8 jeeps even with a stock tune. If you had a tuner you would gain more as you can add more timing and fuel. VP109 IS UNLEADED WITH 105 OCTANE AND 6.3% OXYGEN BUT IT COST 16.00 GALL HERE IN CA. I used it on my 07 with cai and 91 octane dyno tune and used it on my BONE STOCK 2012.
 

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Very cool man, 12.2 is solid on the stock tune. Drag radials make all the difference.

Jim has some good advice above. I always pull my air filter for passes, and I run a mix of pump gas and VP MS109 race fuel. On the stock tune 95-96 octane is where it's at to eliminate knock retard. You'll still get some even on the stock tune running 93 pump gas unless it's totally top notch fuel and a bit cooler out.

There are other little tricks you can do to whittle down your ET.

- Pull air filter
- Remove trunk floor and tray below floor liner
- Pump up front tires to 45psi to reduce rolling resistance

I also recommend getting a Tazer if you don't have one yet. It will allow you to use line lock by pushing buttons on your steering wheel (no physical plumbing of lines) and also enable SRT drive modes which includes Track mode for the transmission. I've verified that Track mode shaves off just about .1 off my 0-60 time. I repeated it back to back on drag radials on the street in the same spot, same day, Sport to Track to Sport to Track (4.0, 3.9, 4.0, 3.9).

You can get down to 11.9-12.0 on a 65-70 degree day and hit 11.8 on a cooler day on the stock tune.

I've found that doing my burnouts in Manual mode with the shifter makes things a lot easier. I get it going in first, then in second, and then shift into third and get them really spinning for just a second or so at the end of the burnout. Usually works pretty good.

On the stock tune you can run up to 22psi or so and still hook up pretty good. I used to run my M/T 20" drag radials at 19psi most of the time though.

It's a lot of fun isn't it? Nice job on getting into the low 12's!
 

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Discussion Starter #5
Thanks cdahl383 for the advise. I hope we get a few warm days in November so I can run the car again.

At what point do 392 owners need to install the IRS brace and one piece aluminium drive shaft? I have read Hellcat owners need to do these two things once they use drag radials.

Thanks
 

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When I do a 50/50 mix of 91 and vp109 ( 2.5 gal each ) it totals 98 octane with 4.02 % oxygen and it will let the tune hold 26 degrees in my 6.1 with mods of cai and 91 octane cmr dyno tune with no adjustments to the tune for the added octane. It also did wonders on my bone stock 6.4 jeep.
 

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Thanks cdahl383 for the advise. I hope we get a few warm days in November so I can run the car again.

At what point do 392 owners need to install the IRS brace and one piece aluminium drive shaft? I have read Hellcat owners need to do these two things once they use drag radials.

Thanks

I've been told from several reputable guys who frequent the track often with both Hellcats and 392's that were good with DR's on the 392 with a stock tune, but if we go to slicks we need the brace. That going to be a package deal for me.
 

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Very cool man, 12.2 is solid on the stock tune. Drag radials make all the difference.

Jim has some good advice above. I always pull my air filter for passes, and I run a mix of pump gas and VP MS109 race fuel. On the stock tune 95-96 octane is where it's at to eliminate knock retard. You'll still get some even on the stock tune running 93 pump gas unless it's totally top notch fuel and a bit cooler out.

There are other little tricks you can do to whittle down your ET.

- Pull air filter
- Remove trunk floor and tray below floor liner
- Pump up front tires to 45psi to reduce rolling resistance

I also recommend getting a Tazer if you don't have one yet. It will allow you to use line lock by pushing buttons on your steering wheel (no physical plumbing of lines) and also enable SRT drive modes which includes Track mode for the transmission. I've verified that Track mode shaves off just about .1 off my 0-60 time. I repeated it back to back on drag radials on the street in the same spot, same day, Sport to Track to Sport to Track (4.0, 3.9, 4.0, 3.9).

You can get down to 11.9-12.0 on a 65-70 degree day and hit 11.8 on a cooler day on the stock tune.

I've found that doing my burnouts in Manual mode with the shifter makes things a lot easier. I get it going in first, then in second, and then shift into third and get them really spinning for just a second or so at the end of the burnout. Usually works pretty good.

On the stock tune you can run up to 22psi or so and still hook up pretty good. I used to run my M/T 20" drag radials at 19psi most of the time though.

It's a lot of fun isn't it? Nice job on getting into the low 12's!
Regarding knock retard, is the goal to eliminate all knock retard, even occasional minimal short term? On a stock tune, with 93 pump gas, with data logging of WOT pulls, I see 0 degree long term and mostly 0 degree short term with sporadic blips (~ 1 sec) of 1-3 degrees timing pull. Do you see short term KR completely eliminated with > 93 fuel?
 

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I don't think you need a loop or one piece driveshaft for a Scat Pack that's stock or mildly modified. Hellcats are putting out a lot more power, they tend to twist the stock driveshaft when they hook up good. If you run slicks you need to have everything set up properly because you will likely start to break parts as they won't spin. Drag radials will hook up good but they will spin a little and give a little.

Ideally you want to see 0.0 knock retard all the time, but that's pretty hard to do. It's common to see some after shift points. But yes if you're getting true knock, then higher octane fuel will get rid of it. I was testing out some adjustments I made to my tune the other day. Was getting up to 2.5 ST KR with 96 octane. Added more race fuel and brought the mixture up to 98 octane, went down to 0.5-1.0 blips here and there, mainly in 5th gear WOT and a couple shifts.

Most tuners will say things like under 4.0 ST KR is okay, or under 2.0 ST KR is okay, but you never want any LT KR. To me you really want 0.0 ST KR. You can see the PCM pulls a degree of timing for every degree of ST KR there is. I'm not sure how much power that is, maybe 3-5hp? I think the idea is you make more power overall running more timing even if you get little blips of ST KR here and there vs pulling more timing out and getting 0.0 all the time. So some low level of ST KR has to be acceptable at some point I think otherwise you forego any potential power gains. By running quality fuel and the appropriate octane, you can minimize it to next to nothing and still make more power without F'ing up your pistons.
 

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Discussion Starter #10
Our local track was open today. Mid 50's and the DA was 550. I ran my fastest time yet at 12.11 at 113.4. My 60 foot time was 1.72. There was a pretty good head wind. I was hoping to crack into the 11's but it did not happen. It will have to wait until next year. I did pull the factory air filter. Did not use VP109 and I don't have a Tazer yet which have been suggested to get into the 11's.
 

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Our local track was open today. Mid 50's and the DA was 550. I ran my fastest time yet at 12.11 at 113.4. My 60 foot time was 1.72. There was a pretty good head wind. I was hoping to crack into the 11's but it did not happen. It will have to wait until next year. I did pull the factory air filter. Did not use VP109 and I don't have a Tazer yet which have been suggested to get into the 11's.
12.1 is quick on the stock tune. Sounds like the car was hooking up good too with that 1.72 60ft.

I highly recommend the Tazer. Running in track mode will drop a tenth or so off your ET. You're leaving a tenth on the table just running in sport mode. That would get you to 12.0. Add a gallon or two of MS109 to a 1/4 or 1/3 tank of 93 pump gas and that will help also. You want to run around 95 octane on the stock tune. Just enough to reduce/eliminate any knock retard that might be showing up and killing a little power, but not too high of octane where it slows the car down (higher octane fuel is harder to light off).

Are you pumping up your front tires? Run them at 45psi. This will reduce rolling resistance. Try to run your drag radials as high as possible without breaking traction. If you can get away with 22psi do it. If not, try 21 psi, then 20 psi, etc. The higher the psi you can run, the better ET/MPH you'll get as there is less rolling resistance.

Don't forget to pull out any dead weight that you can. The trunk floor liner and tray underneath weigh about 25lbs. Don't run more than 1/3 tank of fuel at the track as each gallon of fuel is about 7lbs.

All these little things don't sound like much alone, but together they all add up to get you past that 12.0 mark into the 11's.
 

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Discussion Starter #12
Front tires were at 37psi. I forgot about increasing the psi in the front. I tried the rears as low as 15psi up to 22psi. Today 18psi worked best. Track prep was not that good today. We had a diesel dragster blow up on the track, fox body Mustang dragged his rear bumper in a wheel stand for almost an 1/8th mile. Then slammed down and took a hard left into the wall.

I will pull the stuff out of the trunk. My car has the sub in the trunk that needs to go too. Also will have a Tazer by spring time.

The first time I used drag radials they dead hooked and ran a 12.2. Now every time the car spins it is just how much. Can anything be done to help this issue? On the same track my brother dead hooks every time. He has a 2013 Mustang GT. He is running 12.5's with Hoosier DRs. His mods are a CAI and tune.

Here is a pic of my best run today:

 

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That's a solid pass man!

Air the fronts up to 45psi, get the Tazer and run the trans in track mode, pull crap out of the trunk, and you'll be in the 11's.

Our 392's make a lot of power down low, so they hit the tires hard off the line. Are you running 20" or 17" drag radials on the back? the 20" ones will hook up pretty good with decent track prep at 18-20psi with a decent burnout. If the track prep sucks, they aren't going to hook all that well though. Not much you can do about that short of running slicks. I always try to run on days when they prep the track good, like on bracket racing days. I hook up pretty good on those days. Test n tune days when they don't prep the track that well my car doesn't want to hook up too good.

Your brother dead hooks with his 2013 Mustang GT because the 5.0 is pretty weak off the line without a converter. He has an A6 trans I'm assuming. Those cars don't typically 60ft all that well, but they make up for it on the big end because they make a lot of power up high. Our cars hit the tires harder off the line but because we're heavier they don't pull as hard on the big end. If your car hooks up you will be running high 11's with a few changes and will run low 12's if you spin a little.
 

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Discussion Starter #14
Thanks cdahl383!!

Spring won't get here fast enough. I will pick up the Tazer in the spring. I am running 305/45/18 MT R's.

My brother's car is a stick. He can bang the gears pretty good in that car. He hits 1.8 60 foot most of the time. The 5.0's lack torque for sure. The 392 is a much different driving experience. Even if I spin off the line and he cuts a 1.8 60 I can usually run him down.

The Scat Pack is my first automatic. I have raced Mustangs until this year. The Scat Pack is my daily driver. I have a 2007 GT500 which runs 10's. It's a garage queen but when I do race it, it is a handful to drive flat out with 650 rwhp. The Scat Pack is a whole lot of fun to race.
 

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Thanks cdahl383!!

Spring won't get here fast enough. I will pick up the Tazer in the spring. I am running 305/45/18 MT R's.

My brother's car is a stick. He can bang the gears pretty good in that car. He hits 1.8 60 foot most of the time. The 5.0's lack torque for sure. The 392 is a much different driving experience. Even if I spin off the line and he cuts a 1.8 60 I can usually run him down.

The Scat Pack is my first automatic. I have raced Mustangs until this year. The Scat Pack is my daily driver. I have a 2007 GT500 which runs 10's. It's a garage queen but when I do race it, it is a handful to drive flat out with 650 rwhp. The Scat Pack is a whole lot of fun to race.
I see. The sticks are usually a bit slower than the autos nowadays. You're running some good tires there. I'm guessing your track does not prep all that well sometimes which is why you're spinning. When I run on Sundays I dead hook just about every time, maybe a slight spin at the worst. On Wednesdays I spin almost every time and sometimes I just light it up bad. Only difference is good track prep on Sundays vs not much on Wednesdays.

With the tune and wheels I was hitting 1.61-1.64 most of the year when I hooked up good for 60ft times. Not much you can do if the track sucks though.

I bet the GT500 is a blast to drive! Sounds like a lot of fun!
 
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