More Tracks R Going 1/8 How to gear a low HP Car??

[Locomotion]

Overall, insurance is probably cheaper & event may get done sooner.

 

[318willrun]

I always thought running 1/8 mile on a quarter mile track was to keep cars under 150 mph.
No need for a chute.

Overall, insurance is probably cheaper & event may get done sooner.

I agree, insurance would be a big thing. Also, so many "small tire - no prep" and TV shows about racing these fast cars on back roads with money on the line, and usually they race 1/8 mile too.

 

[B3422w5]

The "problem" with 1/8 mile tracks is that in order to be competitive, you almost have to run a 4.10/4.30/4.56 gear or lower no matter what engine or power level you have.

Kinda kills the street/strip builds unless you're just running for fun.

trying to figure out why you would consider a 4.10/4.30/4.56 any more necessary on 1/8 than 1/4.
Racing either distance, cutting a light and running the number is all its about. What gear you have has virtually nothing to do with either of those. In fact, less gear is more likely to make the car less likely to spin at the hit.
I have actually run a 4.30 gear in every combo i have had, and until 3 or 4 years ago, 90% of my racing was 1/4 mile.
Now its 90% 1/8 mile, same gears. Unless you are in a heads up deal, or a test and tune ET chaser, going a little faster or slower based on gear choice is a not a big deal to most true racers
Cut a light, drive the stripe, no matter what gears you have you will be at no disadvantage to anybody.
You can run 5500 or 8500 at the stripe, it isn't going help or hurt either way in winning a race

 

[YY1]

In the 1/4, the higher geared cars have a chance to "catch up" at the end of the track.

Just look at the other responses to this thread.

Almost every post agrees and even suggests lower.

...and from street racing experience I can tell you my 2.94 gear had a chance to "walk" comparably powered gm cars with 3.08 sets up around 70 MPH, even if they got a slight jump on me out of the hole.

 

[72DMag]

@Sublime one @33IMP I know what you mean about avoiding 9 seconds. Long story short my dad had a 68 dart and we converted it t run 8 seconds. Did the chute, funny car cage, etc.. and after all that we hated the car. It was no longer fun to drive and a pain to get in and out of. Never again will I create a car that fast!!

@1969383S You might be right about me needing a 5.33 gear. The one thing is the lack of low end torque I have compared to a big block. Given all the comments and what mark has said, I think the 5.13 will be a good starting point though. That 1-2 shift is going to happen fast.

Lastly, the 904 does have a low gear set in it. Not sure if that will be helpful with such a short gear ratio?

 

[B3422w5]

In the 1/4, the higher geared cars have a chance to "catch up" at the end of the track.

Just look at the other responses to this thread.

Almost every post agrees and even suggests lower.

...and from street racing experience I can tell you my 2.94 gear had a chance to "walk" comparably powered gm cars with 3.08 sets up around 70 MPH, even if they got a slight jump on me out of the hole.

No.
You can have a 2.94 gear in your car. Have an 11 flat dial in on the car when you know it will run 10.95, and still “ catch up”…..
Look at the many modern hemi Challenger cars. Seen lots of them run 125 mph and only have 11.xx ET’s.. guarantee they don't have 4.30 gears in them. And they “ catch up” big time on the big end. But at the end of the day, still have to cut a light and run the number.


You can also have the car on the bottle to “ catch up” as you put it.
Rear end gear doesn't have to have anything to do with what you are talking about.
I kinda know what you are trying to say. I think your point should be…pick a gear that allows a car to be in its sweet spot the most during a run, and it will run its fastest. That is true.
But that has zero to do with winning races, “ catching up” or anything else you are talking about.
I know one of the best bracket racers in the country who takes off in second gear with a 3 speed automatic, for more consistency, not speed, obviously. Its all about turning on win lights

 

[33IMP]

@72DMag, maybe i missed it, but, what gear are you running, now?

 

[72DMag]

The car has yet to go down the track. I'm finishing the wiring now and then hope to get the glass installed and an alignment done so I can at least take it down the track a couple times by October. I know the weight because it was put on corner scales and the engine was dyno'd but when I saw the calculators saying a 5.50 gear I figured I'd ask on the forum before buying ring and pinion and getting the center section setup.

 

[318willrun]

.... or go 3.55's, maybe even 3.23's and race it like a power glide only shifting once and crossing the 1/8 mile in 2nd gear....

 

[YY1]

At some point a car with a very low gear runs out of gear, unless the engine is built to operate at a very high RPM.

If the engines in two cars and the weight of those cars are very similar, and the difference is the gearing, the car with the lower gears will perform better off the line, while the car with the higher gears will perform better (and continue to perform better) as distance is traveled.

 

[72DMag]

YY1 is correct and being that it's 1/8 mile I won't have enough real estate to get away with the taller gear. I thought about running it like a power glide but not shift twice kinda takes the fun out of racing the car. ;) That could be an option for me down the road depending what the car does.

Thanks for all the comments guys!! Much appreciated.

 

[Deweywinger&howe]

We’re eighth mile at Eddyville & no one runs 5 something gearsl like 4.56 because big blocks will loafif overgeared
One area of concern is if you have a road gear your converter isn’t latched up This is a disaster under any use
Im always amazed by the nmca cars
Ive got lifhter cars with no hp