Understanding 60' times

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71Duster

71Duster

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Last weekend at the local mopar car show they rented the trac and I ran my car for the first time ever. Now I didn;t build a race car its just a warmed over 340 and stock tires etc.

With no prep time IE: 32psi tires the first race on a hot day and hot engine was a slow [email protected] with a 60' time of 2.366

The second run no changes except pushing the car through the staging lanes as I was told and when running in the shade of the tower waiting to warm the tires up to keep reving it to keep cool fuel to the carb and I managed a [email protected] with a 60' time of 2.370

I was leaving the line@2000rpm on both runs.

I had a lot of fun even though I was nervous and had never been infront of a tree both reactions times showed that with a .426 and .280.

My question is everyone thinks my car has more in it, I know I need a jet change but from what little I know and was told I spun bad is my 60' foot time horrid? And what sort of time is possible with traction?
 
A fast car with traction from good rear tires and a good suspension and convertor will 60' in the 1.40's. If your car would do that you'd knock off a full second which would put you in the high 13's. Without adding any engine power. In your case, it might only be a gear and some drag radials.
 
with limited traction available in your combo....look at your mph it has the true indication of horsepower......at 95 mph you probably could get into the high 13s...

a fast 60 foot time is a combo of torque converter...gearing...traction (slicks)...also the engine combo...meaning carb ..cam must match up with your converter and gearing..

any improvement in your 60 foot time will reflect in your times down the track...

my 69 barracuda has very good 60 foot times for the et it runs...usually around 1.47...and runs high 10s...
 
Racing a PURE STOCK 340 I started out with my 60' time in the 2.32-2.34 range. That is with BFG T/A's (205R70-14) on stock 14x5 1/2" rims. I now 60' in the 1.97-2.02 range.
Your car sounds relatively stock, so here are some of the things I have learned.
Your reaction time and 60' times have no bearing on EACH OTHER, but obvioulsy have a great impact at the end of the track.
Rule of thumb is for every tenth you save in 60' times, it will result in 2 tenths faster at the line. When I started in the 2.32 range I was in the low 15's-high 14's. With my 60' times in the 1.97-2.02 range I run in the 13.77-13.89 range.

With street radials, I found that 22-24psi in the rear tires works best.

Get some weight transfer going. Our rules state that I have to maintain my front anti-roll bar, but nothings says I can't loosen the end nuts to the top of the bolt. You can remove yours completely (saves weight off the front end as well)

90-10 shocks, or three-way adjustable shocks (Summit, Comp Eng.) help a lot to get the front end up and transfer the weight back.

Soft shocks in the back.

If you have an adjustable pinion snubber, drop the snubber down.

Run with a 1/2-to-full tank of gas. This will cost you a couple MPH at the end, but help the radials ~bite~ at the tree. Once again, part of the WEIGHT transfer.

If you can adjust the secondaries on your carb have them come in a little later. I have a stock Carter AVS so I can tighten my secondary spring a bit. This keeps the back barrels from opening too soon thereby breaking the back tires loose.

If I hear/feel my rear tires spin I know I have just lost my race.

You have to learn to D-R-I-V-E the car off the line. You can't react like guys with slicks. You can't just mash it and go.

These things will cost you virtually nothing (except for the new shocks) and should help you cut a couple of tenths off your 60' times.
 
I get miserable 60 ft times too, ranging from 2.2 to 2.4 seconds. In my case it's been a combination of small street tires (235/60-14) and axle wrap up causing wheel hop.

The best 1/4 to date is 13.7 @ 102 mph with a 2.2 60' time.
 
That all doesn't sound to bad for a 340 Duster. It is probably a great scream driving the car on the Hwy. with great passing power. Isn't it. (?)

I went to E-town with my Dodge Magnum. It has a 1978 - B engined - 400/727/3.55w/245/60/15 and weighs close to 4 large for sure with me and half a tank of fuel.
A '78 engine is dead on it's heels HP wise by compare. The only power adders I have are headers into a H piped 2-1/2 pipe size, A 750 AFB (Carter) replaces the T-Q and a FBO ignition.

My reaction times were really bad. I couldn't launch the car well at all. I do better in the street. I'd hit the gas and it would leap a litlle and die out. I don't have this problem in the street. Maybe some spin and that's about it.

My 60' times were...... 2.63 - 3.20 for the red light, - 2.45
Trap speed was ....... 88.37 - 88.26 for the red light - 88.61
ET was also slow, but, 15.95 - 16.58 for the red light, 15.78
 
... and another one is bitten by the dreaded 'go fast' bug! A sure clue is any question about how to improve after the first time out to the drags. Welcome. It's incurable. And most all of us are afflicted with the disease.
Fun, isn't it?
 
I've got it really bad. Doc says it's terminal. He said he'd never seen such a case as mine in all his years.
 
It was great fun but first and formost its a driver I like driving there and back.

It's a 340 block now at .060 over with keith black forged pistons stock rods and crank 650 Speed Demon mechanical secondaries 3.55 gears automatic trans with 2800 stall. It runs a Hughes cam #heh2328al

111deg lobe seperation/installed centerline 108deg
intake lift .506/ exhaust .524
[email protected] Intake223deg/ Exhaust 228deg

Stock Heads 2.02 intake 1.60 exhaust

It sounds very tame and its great fun on the street and loves the rpm's on the highway it'll get up and go in a hurry.

For tires there jsut 255/60r15's and I just stomped it from the light. I wouldn;t mind running the occasional street legal night but wanted to understand a few things as well. I have the non adjustable factory pinion snubber and was told to get the adjustable one that it would help, of course guys at the track are trying to sell me slicks etc.

I can definatly see how the addiction starts but I just like cruiseing too much to kill that aspect in the car.
 
71Duster said:
For tires there just 255/60r15's and I just stomped it from the light.
Click to expand...

That's the problem right there. You're treating your street tires like slicks. The adjustable snubber works great with slicks. Street tires like a softer "hit" on them to keep from breaking loose.

Foot brake against the converter (I usually get mine to about 2000rpm) and hold it there. When the last yellow light (on a sportsman tree) comes on, release the brake as you gently apply full throttle. Pretend there is an egg under the gas pedal. It sounds lame, but you have to drive the car off the line and you'll pick up a tenth or two just by changing your habit at the tree. Plus, run 22-24 psi in the rear tires.

You should be in the mid-high 13's with that combo.
 
I air my street radials down to 15 PSI after I unload from the trailer, then just smash the the throttle to the floor holding the foot brake and let off the brake on the last yellow.

I usually spin on the first qualifying run then after the tires and track are slightly warmer I can leave with no tire spin.

I'm running a stock 318 with an Eldelbrock 600 CFM Performer carb & manifold on race gas. with a 2.45 open 8 1/4 and drag shocks.

My 60' is usually in the mid 2.30's with a best of 2.349. that was on a 16.533 RED light pass at 82.87 MPH.
 
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