Ran the car again need some opinions...

So I ran the car again this past wednesday with the new torque converter went from a 2,500 stall converter to a 3,500 stall. Car ran pretty good, but it was a bit slower than my best run yet which was a 11.7. Also got four runs in for the night the 12.083 being the best one for the night and then two 12.1 runs, also it was about 20 degrees warmer than it was when I got the 11.7 and the humidity was about 30%. Also with the new converter, I was able to foot brake and stall it out to 2800rpm and with the old converter I was foot braking it at 3200rpm. Car did launch a bit harder with the bigger stall but it felt like it could have gotten out of the hole a bit quicker and harder with the new converter but it didn't feel too much harder. so my main question is right now i am running a 28x10.5 slick and I am running a 4.11 gear ratio in a 9inford rear would going up to a 4.56 gear with this current converter and tire size help me get out of the hole quicker, and also get my 60ft time down as my 60ft was pretty similar to what it was with the old converter. Let me know what you guys think because I don't want to dump another $200 on a new ring and pinion set and have it run the same times or worse. Also have a set of 26x10in slicks, thinking of running those on the car next time, because the smaller tire will be like re-gearing the axle without costing me any time and money. Also felt like on each run I could have held second gear a bit longer as it didn't feel like i was letting second gear run as long as I could have. The motor also made the most torque at 5,800rpm and the most hp at 6,500 on a engine dyno. Here are the time slips, the first one is my best run with the old converter, and the second one is with the new converter. Probably going to try to get up there next Wednesday, and run it with the small tires and see what and does and decide what I want to do from there.

 

The brake stall numbers indicate the new convertor is not operating as advertised unless you accidentally reversed the numbers.
Are you logging your A/F levels during the runs?

 

Tested the flash stall today by shifting the car into third and bringing it up to ten mph and going wot and it did in fact jump to 3500 before it started to really climb so I think the flash stall is in fact correct. Here is the exact converter that I brought. Also going to try not foot braking it the next time I run the car and also going to try my smaller slicks I have.
http://www.summitracing.com/parts/pma-pa26211/overview/

 

Yes the smaller tires will act as a gear change and yes 4:56 gears will move your Ranchero quicker. My last time out I had the best 60 ft times for me. 1.60 and a 1.565 and I have a 3800 stall with 4:30 gears and M/T 3055 28 x10.2 stiff wall slick. Alot of thing work hand in hand. Hows your traction , what is your shift point, whats your power band, Torque. Any wheel hop? what front shock? Still have the front sway bar? What about a sway bar in back? What motor? What cam? Compression? RANCHERO WEIGHT?

 

That is a good converter.
The reason I asked about data logging the A/F is that if you are running too rich during any part of the pull you are losing a lot of power.
That is why tuners win races.

 

Hey airford, was hoping you would chime in as you have been there done that and ran great times with these big cars too. Traction wasn't too bad that night got a bit of tire spin out of the hole, they weren't prepping the track worth shit that night. My shift points are and I will know this a bit better once my engine guy gets a hold of my dyno sheet as I misplaced the copy that he gave when the motor was built but most of the night I was revving the motor to about 6,000 to 6,500 in each gear. It also seemed like it would rev to 6,500 in the first two gears no problem but once I went into third it would not pull as hard so gears would probably help. Also again with the dyno sheet I will know this better but I want to say it is 3,000 to 6,500. Torque is also 480 tops at 5,800rpm's. As for sway bars they are stock units front and back, no wheel hop. I am also running kyb gas adjust shocks, wish I got adjustable drag shock last year when I put new ones on. Also the motor is a 410 cleveland stroker with aluminum heads and a solid roller cam with the specs of @50 duration 258 intake 266 exhaust lobe center 110+4 and a gross lift of .692 intake and .727 exhaust. Compression is also 12.5.1. I would also have to say the car weight around 4,000 to 3,900.

 

You have alot to work with. Good build. First I would think about the gears to 4.56 and a locker posi if you still drive it on the street much. I have a spool in mine. Drag car only. When you change the gears you will open a can of worms trying to get traction again is my guess. Next I would dump the front sway bar and uppper control arm limit bumpers for better transfer and more travel. Remember that the shocks Lakewood and most other suppliers for the Ranchero will top out if you increase the travel, so if you do this check the travel on the front shocks. I used a shock from a Dodge Dart and changed the lower bar mount. Calculate your instant center, you might want to make a couple of plates to lower the mounting point of your lower rear control arms. Alot of people talk about pinion angle and that needs to be in a postion to make the U Joints work properly and not rotate to a negitive angle during your pass, this will unload the tires. There is more but this where I would look first, or add the gears and fill the tail gate with cement and leave it open when you go to the Drags. Line Lock to get the burn out right too. Another chapter.

 

Pretty much have almost all that stuff excePt for the front adjustable shocks. Have had the line lock for a couPle of years now. I also have a yukon grizzly locker which is like a Detroit locker. Over the winter too I got a set of spon Performance uPper and lower adjustable control arms for the rear, do you have an idea of what I should set my pinion angle to have it at stock specs currently.

 

I set my pinion so that when it's under power (trying to lift the chassis) that it is zero degrees. Inline with the trans, a straight line from the trans to the rear yoke. That is about 1 1/2 degrees when my car is on level ground. I have air bags in both springs in back and ran 12 psi in both and 13 psi in the slicks. People will tell you that I'm wrong with the same psi in the bags, but that's what works in my Ranchero. I have a adjustable anti roll bar in back. I do about a 4 1/2 second Burn out starting in first and quickly shift to second at 4500 rpm. You will fell the slicks get sticky and release the line lock to power out of the burn out. I will find a you tube of my Ranchero at the starting line. It lifts alittle and not much squat.
Go to 3:35 minute mark in thih video and you can see a front view of the Ranchero

http://www.youtube.com/watch?v=EQi5TGgD1pk

 

Cool I will check out with the video, I know it's hard to tell on here but once I get the right gearing in my car do u think it's possible for me to dip into the 11.4's was almost there before I put in the bigger converter. Also what's your current best et so far?

 

I have a dumb question ... what is 'reaction' on your time slips?

 

Not dumb at all 11.7 run was .572 and the 12.08 with new converter was .498.

 

OK, but what does it mean? What is being measured? Is that time included in your final E.T.?

I'm guessing that it involves your human reaction time somehow? From green light to breaking a first beam, or ??

 

You got it!

The reaction time is how long it took the car to get out of the staging lights after you got the Green to go. .500 is a 1/2 second on a .ooo tree. The good drag racers will hit.008 and lower most of the time.

 

Yes you will go faster if you keep working at it. For me it's a hobby and every time I make the first pass of the night with a faint trace of tire smoke in the Ranchero and I scream like alittle kid on Christmas morning.
Best e.t. 11.1 @ 119 MPH. with 1.680 60ft. I'm faster now 7.04 @ 98.1 MPH with a 60 ft 1.565 1/8 mile as we dont have a 1/4 mile track the race currently.
Looking for 10.99 or 6.90 in 100 plus 1/8 mile.

You will have people tell you things to do and you will find out for yourself what work, Enjoy the fun. The Ranchero doesn't have alot of front end travel and is a long wheel base, so I suspect that is not ideal for what we are trying to do. Keep up posted weather you go forward or backwards its all COOL. America needs to put down their I Pan and get back to doing something Real.

 

OK, but is reaction part of the reported E.T.? If that's a yes, then it would seem like working on improving that might be worth as much as spending a few thousand on the motor.

Human reaction time is said to be in the range of .150 - .300 seconds -- so someone achieving .008 means that they are successfully anticipating the green and starting their reaction early?

 

Yeah I think reaction time is factored in I do also in fact have to work on mine because half a secon isn't by any means the greatest. .300 and under is the better reaction times.

 

The e.t timer doesnt start till you leave the stagging lights. the reaction time is not included in the time slip. If you have two cars that run exactly the same time the race would be decided by reaction time. The win light is based on who gets there first,

 

I leave when the 3rd amber lights......I get reaction times from .100 to .080

 

In a word, yes.
The countdown is precisely timed. Most racers have a practice tree to train with so that the reaction becomes reflexive.
There is a huge psychological advantage gained by a fast reaction time, as it distracts your opponent to see you pull ahead out of the hole.