Fast cars with a third pedal...

Who's got them? What's your combo? What does it run? What have you upgraded? What have you broken?
Thanks!

What is your definition of fast?

We'll say 11.80 and faster?? Something that will keep up with a Scatpack on drag radials, for instance? lol

I'll bite.....
440 stroker (493ci)
1050AN Quickfuel 4150 carb
Solid flat tappet cam
Stock NP A833 18 spline
Center force clutch
Dana 60/ 4.56 gears
Total weight with me and 1/2 tank of 93 octane 3926#
Best time is in my sig. Usually runs 11.1's at 123+ thru the mufflers.
Before switching to a Dana, I've broken everything imaginable in an 8 3/4. Twisted housings, U joints, axles, spun purches. Never broke a tranny outright though, but did have collateral damage on one at one time.

That's cool. Thanks! Sometimes I think I should have gone with a 4.10 over a 3.54 in my Dana.

3.54' are nice street gears. If you go to the track on occasion, then something in the 4.10 or steeper range would be in line, but again, it would depend on the rest of the combo. Example: if your engine rpm tops out at 5K, then going to a steep gear would make no sense at all. It always come down to combo......

Agreed. Still deciding on a combo. Sold the engine out of my Bee. Now trying to decide what to replace it with.

72 Dart, 420" 6.1 Hemi, Viper T56, 3.91s, 335 street tires, 3700lbs with me in it,pump 91, 2300ft above the sea, been to track once and best pass out of 4 was 12.09@121.75 with a lousy 2.0 60ft. Track sucked,runs better on the street.

That's cool! I haven't ruled out a Gen III. But I already have a 440 block. A cost comparison is in order, I suppose.

Check out Tim Riggleman's small block Daytona. In the 7's. Runs with the Pro Stick group.

Nice.

How did you get it so heavy? Sounds like a killer street car.

Is this a blue Daytona?

I use to drag race several different stick cars, you can change the first gear ratio to make the car leave harder without changing the rear gear
IE, we used a early A body NP833 23 spine tranny in my old 340 Duster street and strip stick shift car, the stock first gear ratio in them is 3.09
My current street and strip car I'm building now has the O.D. NP 833 tranny with the same first gear ratio and .64 % over drive, I'm using a 3.55 ratio Dana 60 in that car with a 464 C.I. 440 motor on pump gas, hopefully the O.D. tranny will hold up to a little abuse

I have quite a few Coyote Stock customers. They run at 3000lbs, use a 5.0L 435hp rated factory sealed crate engine, must use a single 10 or 10.5" disc and a diaphragm style pressure plate, spec transmissions/ratios, and must use the clutch to shift. Here's some recent slip data from a run...

1.296
3.868
6.059
110.11
7.968
9.610
134.94

When everybody's making the same power, it can be especially sweet when you get the clutch tune just right. When the clutch hits too hard, it either pulls the engine down too far or knocks the tires loose. Hitting too soft is also counter productive, but there's a sweet spot in between where things work amazingly well. Basically you want to match the clutch's clamp to the engine's power, as this can effectively raise the engine's average rpm, which in turn allows the engine to produce more power in a tighter time frame.

Here's a simplified example to help explain why you want to keep average rpm as high as practically possible-

Lets say a car has the power to gain speed at an average rate of 6000 rpm per second in 1st gear. Let's also have the clutch slip until .5 sec into the run with the tires remaining dead hooked. If the car launches at 6k and the tires are stuck, the clutch will pull engine rpm down to 3k by the .5 sec mark. Then from .5 to 1.0 seconds rpm will climb from 3k back up to 6k, as the engine regains the lost rpm. What all this boils down to is that during the initial 1 second after launch, the engine's average rpm was 4500 rpm, which means the engine made 75 revolutions over that 1st second of the run.
...Now suppose that same car launches at 6k, but now the clutch slips just enough that the engine does not lose any rpm over that same 1 sec period. Now the engine's average rpm was 6000, which means it made 100 revolutions during that initial 1 second period.
...Here's the thing- both left from the same rpm, but the launch that didn't lose any rpm actually packs 33% more revolutions of WOT power production into the same 1 second time period. If the clutch also slips just right after the shifts, you can pick up some power production there as well.

When you understand what you need to do, you can likely make things come together on your own. Here's a few things you can do to an overly aggressive clutch to tweak it closer to that sweet spot...
1- less aggressive friction material
2- smaller diameter disc
3- reduce effective diameter of the disc (trim away some of the friction material's face without reducing overall diameter)
4- reduce clamp pressure either by swapping to a weaker PP/spring, different fulcrum or shimming your existing PP away from the flywheel
5- temporarily hold back some clamp pressure with your foot, basically ride the clutch out for 5-10 feet. Adding an adjustable spring loaded pedal stop can make it easier to consistently find the sweet spot in the pedal travel
6- temporarily hold back some clamp pressure with a timed mechanical device (this is what my device does)

Just putting this out there to show you don't necessarily have to have an "adjustable" clutch to be quick.

Adding a 3.09 1st just makes the gear spread terrible. I will drive it more than race it
If you're putting a lot of power to the overdrive 833, I'm thinking you're going to be disappointed with its longevity.

Agreed. Went this route several years back. Actually bent the input shafts twice. Annnnd, I didn't go any faster. Actually went slower. Went back to an 18 spline with 2.65 low and everything is good again.


Also, I don't know if they will chime in, but there are 2 other cars that are pretty impressive. My Son's '69 Dart, street car(Lar414), with a 414 stroker has gone deep into the 11's.

A good friend of mine, OLDIRON has a '67 Barracuda that has gone low 9.90's.

Both cars are very impressive, Just sayin'..........

looking to do an 833 swap in my dart over the winter! 4 speed has so much more fun factor

lots of ways lol, 1.75x.120 wall full road race cage, 14" front steel SRT rotors that weigh 30lbs each,full Interior, front and rear swaybars etc. The cage alone is 200 lbs. Used to weigh 3240 with an iron head BB.

9.97 @ 135 mph 440 915 heads 1050 team G lugged hemi box

Did not know "Lar414" was your son. His Dart is really awesome. You and your son have two really cool Mopars that look great and run very good. I belive his Dart was in Mopar Muscle some years back. And I think he put a crossram on it also if I am not right. Like I say you guys have two awesome Mopars that anyone would love to own. Ron

Wow, seems really cool. Do you think it handles better with the hemi.

Yes.

Definitely, car is balanced but needs more rear spring.

My 3000lbs Dart with R5P7 and a gforce 4 speed has done a best of 9.37. Got lots left in it with more tuning.
Biggest gain was going to an adjustable softlok clutch. From 1.47 60 to 1.32 and its not even perfect yet.

Cool pic

That car is fricken sweet!

I have in my 67 Barracuda a home built pump gas 505 stroker, Edelbrock heads, 950 HP Holley, American Powertrain Kevlar 11" disc&pressure plate, dana 60 with 4.56 gears. runs 10.30 at 130 What have I broke? The 833, the dana gears, the u-joints and a lot of oil pans

Btw i havnt broken anything yet. But i only have about 50 passes so far.

Nice. As long as the oil pan isn't breaking from parts flying through it, that's ok, right?

Never , knock on wood put anything through the pan or hurt any bottom end rotating parts , 6800 RPM's at every shift . Pan damage is from wheel stands.

I forgot! I have had one thing break:-)

[/quote]
That's cool. Thanks! Sometimes I think I should have gone with a 4.10 over a 3.54 in my Dana. [/quote]

I have a 4.10 Dana in my 70 Challenger RT. It is a bit busy on the street though. I am currently using a OD version of the 833 and it is a good offset of the 4.10 on a road trip. But the gear spread and ratio drops is too excessive. But I will be switching back to my Hemi 4 speed once I am thru with the rebuild to install new bearings and new syncro's. The engine is 440 with MW heads, Indy intake and 1050 2 circuit Dominator. Cam is 258/262@50 w 580/562 lift. The Dana and the leaf springs are from a 69 GTX 4 speed car. Have not had it to the track since I got it back on the road as I am afraid of breaking the OD 4 speed trans.
Jerry

I really like this Dart. Looks clean and this is an awesome shot

Go to youtube and search Steve clukey duster. I think you might be impressed. That car has nothing fansy but a Lenco. Chassis engineering shocks front and rear. Stock front suspension. Ladders on floaters. Launches at 6000-6500. Check him out.

Very cool car!

Thank you. I pretty much built it all by myself exept the engine.
Theres an in car vid on youtube from a tnt day. Search for swede4speed kjula.

You said it as thats one nice Dart. Ron

There's got to be more stick cars out there that fit this profile.. Where you at???????

The fellow on the left was fast. Almost like an explosion when he passed by. Skeered me! But then again, fast is relative

Damn thats a great race!!!

The fellow on the left was fast. Almost like an explosion when he passed by. Skeered me! But then again, fast is relative drive










He is fast what kind of car was this?

it was a fairly serious mustang. I think it had a gforce trans.

a couple of fast mopars - mid high 8s both small blocks

Are we supposed to respond to this Lazarus thread?

Ok, I'll do it.
31 Plymouth coupe, street/strip, completed 2 Drag Weeks, mostly stock except for a stroked early Hemi, 8 Holley 94 carbs, t56 magnum, McLeod RTX clutch, Clutch Tamer, quicktime bell, 4.57 Moser 9" , 4 link, coil overs, 8.50 cage, 2750# at the starting line. Haven't broke anything, gone 10.teens at 137. Still needs a lot of sorting, I expect 9's from it.

I guess i fit into this category:

68 charger R/T
505 rb 10.6:1
1050 dom
Jerico dr4
4.30 rear gear
Leaf spring/caltrac
Pretty porky….3900

Runs pretty consistent: 10.75 @ 127

68 Road Runner.

Old 499ci combo with a Jerico DR4, ran 9.72 @ 138mph.

New combo, with 563ci made 140 more HP, and I switched to a Clutchless Liberty 4 speed. Should run bottom 9's, high 8's on a good day.

I don't race much anymore but my best pass was 10.91 at 124 in my Savoy.
493 with Indy EZ heads, mild flat tappet cam, 10.9 comp, Richmond 5-speed with faceplate by Liberty's, Long V-gate, 3.54 D-60, Performer RPM with a QF 1050 4150 carb. Older Hays MK XII adjustable plate and Ram bronze disc.

Gus

How about Peter Willie and his '71 Cuda>

https://www.youtube.com/watch?v=QlfRBLYcKi8


This is the motor I believe>

https://www.youtube.com/watch?v=p7mjI9yj128

Mine isn’t as fast as what you’re looking for, but I’ll bite. Mine went 12.57 @ 113 last weekend, with a soft 1.79 60 ft and sloooow shifts. It took 9 passes, but thats the first complete pass the car has run. From here I can try to launch it harder and shift it faster.

Do you guys find shifting slow affects trap speed or et more?

Combo is stock stroke 440, Racer Brown ST-21 (254 @ .050, 520 lift), 107 LSA, RPM intake with an 850 DP, Stealth heads, 18 spline with a Ram Powergrip HD, and 4.10 8 3/4 (reason for babying the launch and shifts).

The last 3 passes the clutch seemed to slip in first, I pedaled it some and it locked up and held for the rest of the run. But I was actually thinking about throwing a 727 in it to see what it runs with it

In the past (racing is 99% dead over here so meanwhile sold the car) I have gone 8.9's with my Challenger.

Guestimate at around 2900lbs
528 pumpgas, flat tapped cammed, single dominator, Hemi
Gforce clutchless 4speed and adj. clutch I believe from Hyatt.
Dana60 with 456 gears and 33" slicks.

Had some topend troubles with the engine so was potential a 8.7 I guess.

My junk is heavily inspired by the sweed 4 speed r5p7 11.1 358 g force gf5r 5 speed Dana leaf spring cal tracs goes 9.50s 142 in the heat recently figued out I'm driving through the clutch over 8000 rpm I leave at 6000 shift at 9 go through the traps around 9500

Have a 70 cuda with an alum 572 hemi and a G5R-Gforce 5 speed. When i took out the wedge and put the hemi in, the car hasn't been on the clocks much. They did turn them on at a no prep event in final round and it went 6.0@115 on motor in 1/8. Tranmission isnt clutchless, and it has 2 kits on it. I use a twin disc slipper and it runs on holley efi with individual coil packs. The car is on a 29X10.5W or a 28X10.5 and currently has a 4.10 gear. Currently putting together new motor for it and doing some upgrades to rear suspension.

Thanks for sharing, looking for inspiration. I'm putting together a 69 Dart stock bottom end/head 5.9 magnum, cam/springs, air gap intake, Centerforce clutch 440 source flywheel, 2.66 23 spline A833, 8 3/4 3.23 gears (I have a complete 3.91 742 center if needed) Hoping it will run in the 7's 1/8.

I have one I still need to sort out. ‘74 cuda, 3650 race weight. 511/trickflow 270, tkx 5-speed. I managed to make a couple easy passes this summer but didn’t have a rollcage yet so I launched and shifted easy.
Went 11.26@130.5.

https://youtube.com/shorts/sYdGhhFns7g?feature=share

How do you like the TKX gearbox? Does the shifter go smooth at high RPM's ? I haven't read many reviews about how they react on the strip with some HP in front of them.

Gus

The shifter I got from silversport is a bit of a long throw. First and second gear are a bit lower than ideal. 5th is really tall.
I shift at 67-6800 It still seems a bit catchy at high rpm but it could be my clutch needs more engagement. I’m not in love with the hydraulic setup because I have to push the pedal clear to the floor before it disengages. Although that could be adjustment issues. I am hoping I can shim it. I think it will be a nice setup once I have it worked out. But I do feel it’s going to be a better street trans than strip. And with a smaller cubic inch setup I think the gearing would be better suited. My 511 really starts to pull hard once I hit 3rd.
Fwiw I’m running a 29” slick and 4.10 rear. I still think mid 10s aren’t going to be a problem once I start making real passes.

Thanks I have a few of my 833 customers asking me about converting their cars over to some type of OD box. The online claims as to the strength of this box are as usual seem highly inflated. I have built a few T56 transmissions and the design prohibits high speed power shifts even when the gears are face-plated.
I may just sell a few of my transmissions and buy one of these boxes as my car is more street than strip right now. I only hope that is will hold up to the torque and weight of my car with sticky tires. I will probably install the adjustable clutch or try one of those Clutch Tamer deals to keep the teeth on the gears.

Gus

I have done my research as far as strength, there’s plenty of guys out there running 9s that like them. The guy at silversport claimed that the 600ft lb. Rating of the tkx is underrated.
The .68 overdrive is probably nice for a lot of people. But with the cam I have in my car, I have to be going 75mph to even use overdrive.

Years ago when I dealt with Kiesler and thier Tko 600 tranny, it was rated at 600 ft lbs. my engine did not produce that much, but maybe within 40-50 of that. After I broke the tranny, i was told that launching on slicks at the track spiked the shockload above the 600. I got into a nasty brawl with them and they did end up sending me the broken 3rd gear and cluster gear for free. I installed it myself.

I then had the gears faceplated by liberty. I broke the 3rd gear again on the very first pass at the track as well as split the main case. I then went with a jerico.

Point is, i’m not sure what the torque ratings mean if we have no idea of what the shockloads are. A major factor is the clutch. The adjustable slipper type will reduce the shockloads on the shifts.

Just added this info for consideration no matter what trans is used. Good luck.

A stick car really shouldn't deadhook. I ran the same combo in 2 different car. One with 10.5" tires, and one with 14" tires. The old car never once had a problem with the trans. The new car will deadhook every where we went, and broke first gear in the Jerico. Yes I run a slipper clutch, and only 250lbs of base pressure. Will be interesting to see what the new Liberty does with an extra 140hp, and 90ft lbs of torque.

and we’re counting the days until your last shovel of snow is thrown and the mosquitoes hatch….

When you don't want a car to dead hook, you then have to hit the tires hard enough to knock them loose. Only 250lbs of base tune in a slipper may sound like a soft hitting clutch, but low base just means the balance of the clamp pressure required to get the wheelspeed you want has to come from centrifugal assist. The more traction you have, the harder you gotta hit the input shaft to get the wheelspeed. Then there's the fact that a clutch tune that relies heavily on centrifugal assist will hit the input shaft much harder than it needs to after a WOT shift.

I'm all for adjustable base, but for most applications the adjustable centrifugal assist feature leaves potential on the table. Torque x RPM, highest average number wins if you can get all that power to the track consistently. More launch rpm adds area under the engine's rpm trace, which means the engine will produce more power strokes in a given time frame. But what happens after the shifts can also add area under the engine's rpm trace.

With the typical diaphragm, B&B, or Long style pressure plate (spring pressure only, no added centrifugal assist), the drawdown part of the engine rpm trace after the shift will be pretty linear, basically a straight line like on this graph below...



With a SoftLok style "adjustable slipper clutch" that uses counterweights in addition to spring pressure to clamp the disc, the drawdown part of the engine rpm trace will form a gradual curve. Because the centrifugal counterweight component relaxes as the clutch pulls engine rpm down, overall clutch clamp pressure relaxes as well. Note that engine rpm initially drops very quickly after the gear change (trace falls almost straight down initially), but then the trace begins to curve as the clutch gradually loses it's ability to pull the engine down any further...



An advantage you get from the curved engine rpm drawdown shape is that it adds area under the engine's rpm trace (more engine power strokes in a given time frame). If the clutch had not slipped at all after the above 1/2 shift, the ratio change dictates it would have pulled the engine down to around 5245rpm (input shaft speed) after the tires hooked back up. But because the SoftLok style clutch has an additional centrifugal component, clamp pressure gradually relaxed as the engine lost rpm, which in-turn gradually slowed down the rpm loss. Because the car was also gaining speed while the clutch was slipping, the delayed lockup point raised the minimum rpm after the shift to 6302 instead of drawing the engine all the way down to 5245rpm as predicted by the ratio change. That added clutch slip time effectively tightens up the engine's operating range, which in-turn allows the engine to operate higher on the plateau of its HP curve.

Going back to the static-only (no added centrifugal assist) straight line clutch graph, it's important to know that you can adjust the angle of engine rpm drawdown after the shifts by adjusting the clutch's static clamp pressure. Note on the below graph that the angle of drawdown after both shifts are basically the same, while the drawdown after launch is still straight but the angle is different as launch rpm was drawn out over a longer time period...



The above difference between launch and after shift drawdown angles was made possible by externally controlling throwout bearing position during launch. Basically the throw-out bearing was not allowed to fully retract during launch, which prevented the full force of the clutch's spring pressure from clamping the disc. The throw-out bearing was then allowed to retract shortly after launch, which in-turn increased the clutch clamp pressure available for the shifts. The angle of drawdown during launch is adjusted via throw-out bearing position, while the angle of drawdown after the shifts is adjusted via static clamp pressure. In the end you end up with more clutch slip during launch, and less clutch slip after the shifts.

Here's the SoftLok style curved drawdown shape compared to what the "static only" straight drawdown could look like if static clamp pressure were optimized. Notice how the "static-only" (no centrifugal assist) straight-line drawdown angle can be optimized to add even more area under the engine's rpm trace than the traditional SoftLok style curved drawdown. Also note that the initial drawdown after the shift is not as steep. That flatter angle indicates energy is leaving the engine's rotating assy at a slower rate initially, which in-turn makes it easier to keep the tires stuck thru the shift. Because the engine is producing power at a quicker rate during the optimized "static only" straight-line drawdown, the clutch lockup point occurs sooner, which then allows the engine to get a head start on its climb to the next shift point...



When you add external throw-out bearing position control to the "static only" (no centrifugal assist) straight-line drawdown, it allows you to take advantage of much higher rpm launches without knocking the tires loose. That adds even more area under the engine rpm trace without pulling the engine down below its torque peak. The resulting high rpm dead hook launch really shines on a crappy track, it also reduces the need to adjust tire pressure and launch rpm for the purpose of controlling wheelspeed. Without the need to control wheelspeed, you will likely be able to make use of less first gear ratio, which will in-turn allow tightening up the gear splits if that is an option for you. Little gains here and there, but it all adds up.

In the end its much like a quick automatic transmission car. A less efficient coupling (converter) allows the engine launch higher and gain rpm faster, while also reducing rpm loss after the shifts. The increase in power production shows up as more area under the engine rpm trace, and that added power production more than offsets the loss of mechanical efficiency.

In my opinion, in most cases the traditional "adjustable slipper clutch" style centrifugal assist clutch tune is becoming outdated tech. First the centrifugal assist clutch tune limits your ability to take advantage of launch rpm, then it hits the tires harder than it needs to after the shifts. Knocking the tires loose after the shifts is usually what prevents guys from making the switch to radials. Even if you have a modern ECU that allows momentarily reducing power to absorb the spike after the shifts, those momentary power reductions still cost you ET vs a properly adjusted "static only" clutch that needs minimal or no power reduction after the shifts. When you combine a suitable static only clutch with the ability to raise launch rpm by controlling throw-out bearing position during launch, the adjustable centrifugal assist feature in most cases becomes obsolete.

Grant

I run a lot of counterweight. I also do not have as deep of a first gear as a "normal" stick car. Don't need it... and yes it helps with the splits. 2nd gear slider is the most abused part on a clutchless trans.