Need more power on 06 coupe, disappointing drag times

[Schulmann]

Finally yesterday I had an opportunity to make a couple of runs during a drag race night with my new 06 coupe. Temperature was 60F and humidity 55%.

What a disappointing night. My best time was: 1.8sec / 12.5sec / 117 mph
I was the only GEN3 viper so I have no other reference.
However GEN2 Vipers were hammering me on regular basis with 2.0sec / 11.9sec / 122 mph

As the engine's temperature increased, my trap speed decreased very linearly to 110mph.
I just couldn’t go above 112mph after 5 runs. Clearly the engine was missing power.

I already removed my cats and the cross over pipes and replaced the air filters. (Very basic staff)

What else can I do to get more power ?

A more agressive CAM ?
VEC3 ?
Alum Fly wheel ?
New throttle body ?

[PaViper]

You should have swapped cars with a Gen II driver to rule out the driver factor

[Shandon]

Go with the Vec3 and a good tune at a Dyno. You will pick up some good power!

[black mamba1]

Are you running the run crap tires? Also, there could be many factors, what rpm are you shifting at? Get your car dynoed to make sure it actually is the car. When I first got my Viper I raced a yellow 911, a 1996 model slightly modified. He kicked my ass b/c I was too excited and spinned my tires all the thru first and thru most of second. I was catching him....but the race was over b4 I actually caught him. On the second race I kept it straight thru first, but spinned badly during the shift to second, but I still caught him in second and left him. My point is, it really might not be your car......

[SnakeEye]

Paxton, gears and a good tune should put you in the 130's.

[DSG2003SVT]

I've seen stories similar to this. Stock or slightly modded Gen2s running better than stock/slightly modded Gen3s. Is there a logical reason for that? Could it possibly have anything to do with the weight distribution biased to the rear more on Gen2s? 450hp vs. 500+hp with similar weight...I just can't make sense of it. Anyone have a reason?

[MikeR]

I would try having someone else drive your car. If your running a 1.8 60 ft, thats really good, but soemthing is going wrong. Or maybe your car has a really bad tune. I sent my computer to DC Performance and it made a BIG difference.
Your car should be breaking into the 11's, even with just exhaust.

[viperjim]

Originally Posted by MikeR

I would try having someone else drive your car. If your running a 1.8 60 ft, thats really good, but soemthing is going wrong. Or maybe your car has a really bad tune. I sent my computer to DC Performance and it made a BIG difference.
Your car should be breaking into the 11's, even with just exhaust.

My car only has a tune and air filters. My first run was a 12.5 and after 6 more I had gotten it down to 11.75 @121. Proper launch is key along with maximizing your shift points and shift speed. I believe my car is good for 11.5 as it sits with a gifted launch. Best of luck.

[valentine_viper]

Originally Posted by viperjim

My car only has a tune and air filters. My first run was a 12.5 and after 6 more I had gotten it down to 11.75 @121. Proper launch is key along with maximizing your shift points and shift speed. I believe my car is good for 11.5 as it sits with a gifted launch. Best of luck.

What rpm do you shift at? If I run it out in 3rd, i can't seem to better than about 115 mph. But to get into 4th, I have to short shift the lower gears a little. This has gotten me up to 118, but no higher. Har hs been dyno'd and made healthy numbers.

Is this normal? What's your technique?

[viperjim]

Originally Posted by valentine_viper

What rpm do you shift at? If I run it out in 3rd, i can't seem to better than about 115 mph. But to get into 4th, I have to short shift the lower gears a little. This has gotten me up to 118, but no higher. Har hs been dyno'd and made healthy numbers.

Is this normal? What's your technique?

I power shift thru all 4 gears when the red line light comes on.
My car has not been on a dyno. I sent the controller to DC Performance in California and they reprogrammed it and UPSed it back.
The problem with getting the car off the line in stock configration is a combination of stock run Flats that are too hard to stick and a finicky clutch that does not like to be fanned. Ironically, my first run of the day I heated up the tires well enough so that they did provide excellent traction. I launched at 4000 rpm and tried to ride the clutch. I ended up totally smoking the clutch and had to shut down the run. That works for my '69 Corvette with a 427. Its clutch is aftermarket so I guess I am allowed to abused it more than the unforgiving factory clutches.
After the Viper's clutch cooled down, I started holding the rpms at 3000 and brought the clutch out fast. The stock clutches grab as long as you don't create excessive heat. My best run spun about 40 feet but dug in well and felt good. Its all in the launch. I'm running in mid September with the Corvette Club as they invite the Viper Club. My goal is to eliminate the wheel spin entirely. There is a guy on the Corvette Forum who has detailed proper launch techniques in a C6Z06. It would be good reading for you as the cars use a clutch that reacts similiarly.

http://www.rangeracceleration.com/Launch_Tips.html

I ordered a throttle body from X-Metal and have a corsa exhaust sitting in one of my warehouses. They are this winter's projects along with a rear gear change.
Best of luck racing. jim

[JonB - PartsRack]

Get rid of Run-Craps
3:33 or 3:55 gears
ALUM FW
D-C PCM


You dont need more power. 1st re-gear/reflash the power you have, and minimize wheelspin.

[valentine_viper]

Originally Posted by viperjim

I power shift thru all 4 gears when the red line light comes on.
My car has not been on a dyno. I sent the controller to DC Performance in California and they reprogrammed it and UPSed it back.
The problem with getting the car off the line in stock configration is a combination of stock run Flats that are too hard to stick and a finicky clutch that does not like to be fanned. Ironically, my first run of the day I heated up the tires well enough so that they did provide excellent traction. I launched at 4000 rpm and tried to ride the clutch. I ended up totally smoking the clutch and had to shut down the run. That works for my '69 Corvette with a 427. Its clutch is aftermarket so I guess I am allowed to abused it more than the unforgiving factory clutches.
After the Viper's clutch cooled down, I started holding the rpms at 3000 and brought the clutch out fast. The stock clutches grab as long as you don't create excessive heat. My best run spun about 40 feet but dug in well and felt good. Its all in the launch. I'm running in mid September with the Corvette Club as they invite the Viper Club. My goal is to eliminate the wheel spin entirely. There is a guy on the Corvette Forum who has detailed proper launch techniques in a C6Z06. It would be good reading for you as the cars use a clutch that reacts similiarly.

http://www.rangeracceleration.com/Launch_Tips.html

I ordered a throttle body from X-Metal and have a corsa exhaust sitting in one of my warehouses. They are this winter's projects along with a rear gear change.
Best of luck racing. jim

That sounds like like pretty much the same thing I do, but I don't powershift. Your trans must be much smoother than mine. Powershifts are out of the question for me.

I also have the DC reflash, but if I shift near redline into second and third, I am only a few 10s of a second away from the finish line when I shift into 4th, so there isn't much benefit. Do you have gears, or does my car just not rev as quickly as yours?

[valentine_viper]

Originally Posted by JonB - PartsRack

Get rid of Run-Craps
3:33 or 3:55 gears
ALUM FW
D-C PCM


You dont need more power. 1st re-gear/reflash the power you have, and minimize wheelspin.

Thanks for the tips, Jon. I do have a light weight flywheel, but haven't installed it yet. I already have the DC reflash. That improved low and mid range throttle response and power, but only added one or two mph on the top end. Not sure if I want to do gears yet or not. I figure if I go that route, I might as well get a Quaif. I've heard they improve cornering quite a bit. What are your thoughts on that? Is a Quaif worth the money or would I be better off just changing the gears out?

[viperjim]

Originally Posted by valentine_viper

Thanks for the tips, Jon. I do have a light weight flywheel, but haven't installed it yet. I already have the DC reflash. That improved low and mid range throttle response and power, but only added one or two mph on the top end. Not sure if I want to do gears yet or not. I figure if I go that route, I might as well get a Quaif. I've heard they improve cornering quite a bit. What are your thoughts on that? Is a Quaif worth the money or would I be better off just changing the gears out?

Most shops recommend the Quaiffe rear if you do a gear change. I'm debating between the 3.33 and 3.55's.

[Schulmann]

I shift at 6000 rpm deep enough. I could maybe shave a couple of 0.1 sec but I am stucked with the disappointing trap speed. Over the night as the engin's temperature encreased my trap speed dropped to 110mph.

With my 2000 stock Viper I was hitting on regular basis 12.0 - 12.2. My worst time was 12.5. Whereas with my 06 coupe my best time is 12.5

I have read a couple of posts about the GEN3 PCM. It seems that the WOT signal is only triggered 3 sec after the pedal is pushed into the floor.


I am not the only one with this issue. My friends with GEN2 Vipers tell me that they smash the GEN3 Vipers on regular basis.

[Nader]

If you got the DC program, I would guess Dan eliminated that and that is why throttle response is better.

[MikeR]

Everyone has their opinions, but I felt it best to not launch at 3 or 4k rpms. I was downabout 1500 to2k rpms and kinda just bogg it out of the hole. If you try and launch hard you will just spin. And when i say Bog, I dont mean stalling it out, but I launched almost like I was leaving a stoplight on the street and then accelerated. It was good for plenty of 1.8 60 fts on runflats and pulled same 60 fts on PS2's. What helped alot too, was running about 25psi in rear tires.

[Schulmann]

Who is the contact at the DC performance ?

[Nader]

Dan Cragin 310-841-6996

[RayC]

Am I the only one who thinks it may be possible for something else to be wrong. I would check things out and maybe dyno before mods. You had .2 sec quicker 60 ft. (1.8 to 2.0) times and then the Gen 2 ran you down on there way to a .6 sec faster quarter? I would agree with grip/tire issues but you were faster 60 ft. I have never been run down by a stock Gen 2 but have had them get out of the hole on me, in which cases the opposite has happened and I ran them down (in stock form). Check things out first this doesn't seem right. I can also say that the gear (mine is 3.55) does wake things up alot.

[Hamrhead]

I ran my '06 Coupe when it was stock and managed an 11.90 @ 122.34 w/ a 1.94 60'.

I launched at ~3,000 rpms, spun about 5-7', and shifted as quickly as I could (NO Powershifting). Got into 3rd gear and left it there through the traps. The instant I went through the finish line the rev limiter kicked in.

Temp was about 70 degrees and somewhat humid that day.




I can't wait until the weather cools down to try again with my mods - Green Filters; DC Tune/170 T-Stat; Corsa Track; 3.55 gears.
I'm hoping to run 11.50, or quicker.The car is definitely waaay more fun on the street now!!

[JonB - PartsRack]

Originally Posted by valentine_viper

Thanks for the tips, Jon........Not sure if I want to do gears yet or not. I figure if I go that route, I might as well get a Quaif. I've heard they improve cornering quite a bit. What are your thoughts on that? Is a Quaif worth the money or would I be better off just changing the gears out?

The absolute # 1 bang-for-Buck$ performance (acceleration) upgrade is a gear swap.
Free Bonus: The car SLOWS DOWN quicker, too. To a lesser degree, but similar benefits derive from from a lightened flywheel, and from lighter road wheels. But Is a Quaife worth the $?

I hate to 'waste' anyones money, but here is my honest eval: For Corners, YES! The Quaife Torque-Biasing Diff is an "Unfair Advantage" (literally in some venues) for roadcourse and Auto-X. Straigh-liners.......... not really, unless OE is busted.

2003-2006 rear diff OE hydro-locks suck. OE works OK at corners when new, but have terrible endurance. If you have roadraced your car before the 3-year, 36k mile warranty (some have longer) I bet you WILL be seeking a rear end OE rebuild. The ones we have pulled for gears are barely worth re-installing ! (This was NOT so with 92-2002 Posi-Track.) Dodge appears to have fixed this for 2008 with a GKN Posi.

Drag racers should invest in stronger driveline upgrades but DONT need a Quaife. But if the OE hydro-lock is toast, and you wanna add a GREAT PERFORMING gearset at the same time, ditch the OE hydro-lock. We hope to have 2 - 3 options for mule testing in about 2 weeks.

[Viper X]

Schulman,

As one prez to another, both with 06 coupes, I have found that the 05 and 06 cars are generally down on power from the 03 and 04 cars. Keep in mind that power does vary from one car to the next, but not that much. I have an 06 coupe that seems weak to me at only 448 rwhp and 463 rwtq with K&N's, headers and a tune. My 04 made more power stock than my 06 does modded. Here's what some knowledgeable people tell me:

1 - When the SRT-10 truck came along, SRT had problems with pinging due to the weight of the truck and the Viper engine received knock sensors and revised engine tuning / programming. Timing is reduced with heat and therefore power. This is evident from your post. Cool the car off, ice the intake manifold and power will return. We reaped the benefits of this change as it was applied to all Viper engines.

2 - Also, due to emissions regs, cam shafts were indexed more conservatively. One of our local engine builders discovered this when he had to build an 06 coupe engine for the T-1 racing class, which means everything needs to be basically stock. His "before" engine dyno showed 510 hp. After revising the cam timing and a minor tune, that same engine made 570 flywheel horsepower thru stock exhaust. I started bugging him shortly after I bought my 06 coupe. I found it to be, well, a slug as Vipers go. I'm currently working with him on a kit (my car will be the test mule) that he plans to make available to all of us that will help us achieve more power.

3 - On the subject of Gen II power, I think we'd all agree that they are under rated when it comes to hp / tq. The Gen III's tend to be rated more accurately. I never had a Gen II run me down in my 04, in fact I generally either beat them or "went around them". I don't think I'd do as well in my 06, even with the mods.

I'll keep you posted on the upgrade.

Good 60 ft times by the way.

Dan

[Snakester]

A 4000 RPM launch seems VERY high for run flat tires, I prefer 2000-2500 RPM launches. Then again a 1.8 second 60 ft is very good.
I'd also suggest dynoing your car because your trap speed is relatively low. Icing your intake would help with heat soak, and run the rears at around 26PSI.

[Schulmann]

My launches are very consistent. I am lunching very quickly.
My reaction time is below 0.200 and the 60ft time always below 2sec with a 1.8s average.
The track is not sticky so it is not possible to get below 1.7.

I am happy with my launch times. I could likely shave another 0.2 sec.

The problem is clearly visible in 3rd gear.
The Gen2 Vipers are passing me like rockets. Looks like a 50hp difference.

As I have indicated earlier my trap speed dropped from 118mph to 110mph at the end of the night.


So basically what you are saying guys is that the PCM has a very conservative ignition tuning and the cam has a mild setup ... sounds good for me. I will have to find a solution to free up some power.

Ah yes and the rear end .... It has 4500mi and already makes strange noises and acts strange.

[2002_Viper_GTS_ACR]

My 2 cents.. (which is worth more then other peoples 2 cents )

1st .. I have had in my arsenal a 2002 ACR, 2005 Stock and 2006 Paxton Coupe. I have personally put over 80,000 miles through these 3 vipers.

Here is honest to god feedback from a guy who would actually know, and has drag raced them all:

1. gen 2s have better tires stock for stock. Ditch the run craps and you'll see the difference. Hell even get ps2's and your tires will be BETTER then stock gen 2's (ps1s arnt as good as ps2s).
2. gen 2s have better WHEELS stock for stock. We are running a damn 19 inch stock rear on gen 3s, that means we effectively have a HIGHER gear ratio then thee gen 2s even if you didnt add to it with the 345/30s being even yet still a slightly taller tire then the 335/30s that the gen 2s have (sure we get a slightly bigger patch too, but being that we have run craps, its of little value). So they have 18 inch wheels with 335/30 tires, we have 19 inch wheels with 345/30 tires. Again our power has a mechanical dissadvantage to theirs at turning the wheels (size vs size).
3. Gen 2's have a better posi then the gen 3s... HOWEVER at drag racing, if you get the tires hot enough, this becomes less critical, as you will get both tires to dig in, and the posi will do an effective job at DRAG RACING.. not so great at road racing, but thats not what this post is about.
4. gen 3s are LIGHTER then gen 2s, so we most certainly on paper have the power to weight advantage. and I believe we have a slightly better CD (coefficient of drag).. So why dont we destroy them ?? 50 more hp, lighter weight, better CD ?? Simple... see #5.
5. gen 2 pcms are BETTER then gen 3s when it comes to consistency. Our F'in gen 3 pcms decide to screw us when the heat starts coming on in a gen 3. A gen 2, just keeps you pretty consisten, up until you over heat.. (lol). The gen 3s pcm is protecting us against over heating and pinging (05+), a gen 2 pcm cares a lot less about over heating and nothing about pinging. I consistenly could hot lap the Sheet outta my gen 2, and nail 11.50's one right after the other... set your clock by it... but my gen 3, I could get 11.50's only within a small window.. and this is it.: Car needed to sit after arriving at the track... about an hour would be suffiecent at most, then get in line, keep the car off and cool until I got to the burn out box, do a nice burn out, until you see smoke coming off the tires(any more then that, and your show-boating) get to the light, screw the etiquet of you light up one, he lights up one, then you light up the other.. you just get there and pray he hurrys the hell up (if your racing someone else). Then Launch the car between 1700-2300 (at most on street tires), roll HARD on the throttle, but not too hard that your spinning your times away. Run that Bee-atch up to 6000 and SHIFT quickly (there is more there in the rpms so dont PRE-EMPT the fuel shut off by trying to shift at 5900, because you think in 100 more rpms fuel cut off will occur. I believe it actually happens at 6250. So again, hit 6000 and pop the next gear. I run this thing through ALL 4 gears... run out 1st, 2nd and 3rd and go right into forth, even if there is only 10 feet left (its more you just dont know it) between you and crossing over the line. Running out 3rd never worked for me, i always hit fuel cut off, and always seemed like the car wanted to unload more of that bottem end torque, begging for me to go into 4th before finishing the run.

If the car didnt get to hot (and most likely it did), you can quickly get right back to the stagging area, and try again. That really is the #1 problem with the gen 3s is that damn pcm doesnt like for the car to get hot, once temps climb it seems to be either taking out timing, or adding more fuel (aka rich and fat, and lower power). The gen 2s dont do this anywhere as bad.

Gen 2's you can "hot lap them" and that lets you do something significant... learn its shift points and its launch. A gen 3 will screw with you if you hot lap it, becasue if you try to learn your launch or your shift points, your doing it with a power delivery system (engine) thats constantly varing how much power its going to give you. Get a gen 2 hot, and it still pretty much delivers that same power within a range of + or - 20 degrees. (195-215).

If the 03 and 04s are "making more power" then 05 and 06, its because of the pcms. I think the pcms got more "woosy" in 05 and 06, again favoring more heat protection then power delivery.

Jon

[JonB - PartsRack]

Originally Posted by Schulmann

My launches are very consistent. I am lunching very quickly.
My reaction time is below 0.200 and the 60ft time always below 2sec with a 1.8s average.
The track is not sticky so it is not possible to get below 1.7.................Ah yes and the rear end .... It has 4500mi and already makes strange noises and acts strange.

Sub 2-sec is a good place to be. (congrats...you have advanced beyond novice!)

Get that warranty report in NOW. Change-Check-strain the fluid for hydra-lock debris.

If they offer to change/warranty the diff, let us rebuild the new one for you. Turn around in 3 days, with an 08-setup, or a Quaiffe, with gears. The dealer can do the R+R under warranty. Once diagnosed, we can even do it in advance, and do an exchange. Thinking ahead, if an 03-06 diff goes out in 2008+, I hope the replacement is the '08 posi... WONT happen till 03-06 supply is exhausted, but I look to a supercession at that time.

[mike007]

Gen 2 RULES!!!!!!!!!!!!!!

[DMan]

I've dragged my GenII and my GenIII, but I'm no tuner by any means. But, if your car is running 110mph in the 1/4, something's wrong. This isn't a GenII vs GenIII issue, somethings wrong with the car.

My 2000 RT/10 went 12.3@118, bone stock first month I owned it.
My 2003 SRT/10 went 11.93@122 bone stock with runcraps the first week I owned it.

Your 60ft times prove you can drive it out of the hole, the hard part (although I find these cars pretty easy to drag), I would guess it's not you ... somethings "off" with the car. I'd recommend dyno ... undo mods if you can, dyno, and progress back thru the mods.

But forget the ET, your mph shouldn't be 110mph ... on runcraps, in 100 degree weather - unless you're in Denver & pulling a trailer, uphill, against the wind, with a parasailer, ...

Good luck.

[FikseGTS]

post those 11 second SRT timeslips here:

http://www.dragtimes.com/Dodge--Viper-Drag-Racing.html


now many stockers in the 11's on there....