[63Futura]

What gearing are people running in the 1/4 with a 275 Radial and how fast ?
Done a bit of searching but everything these days is 1/8 not 1/4

 

[cartruck]

I think you will find that the gear ratio is more dependent on what you can power manage with that tire than final rpm at the stripe. If you hit it with enough power your ideal gear ratio for rpm at the end of the pass will not be easy to get to leave. That being said I also think you will find that a lot of cars because of this end up with gearing that would get them through the 1/4 even though they only go to the 1/8th.

 

[63Futura]

So lets say a SB making 730hp with 1.8 glide spraying a 36 jet at 3300lbs
Would it pull a 3.5 gear or will 3.9/3.7 be better ?
Happy to spin it to 8k if needed
I know it probably should have a 1.69 1st gear but just not possible at the moment

 

[B Williams]

So lets say a SB making 730hp with 1.8 glide spraying a 36 jet at 3300lbs
Would it pull a 3.5 gear or will 3.9/3.7 be better ?
Happy to spin it to 8k if needed
I know it probably should have a 1.69 1st gear but just not possible at the moment

I had a 3.89 in my Corvette with a 1.80 glide..... I had a SB about the same power (755) and jet (36N) as you. I had an 8500 chip in it and it never hit it so.....

Normally I race 1/8th mile but there was this time I was making a test hit and noticed the 1/4 mile clocks were on..... Anyway car went an [email protected] cutting it at the stripe.

Initially my plan was to run it all the way...... anyway about the 1000ft mark I began to think that the car was going way too fast to get it stopped with no chute and the fact that I only have a 8.50 cage and car still the stock factory brakes on front..... So I chickened out and killed it right at the clocks and got on the brakes...... I did manage to get her stopped but it was exciting.

After that I switched the car over to a 4.30 and 1.69 Glide and know I can only do 1/4 mile on motor.

Will

 

[cartruck]

That 1.80 gear is going to fight with you at some point, it may also dictate what your rear gear needs to be. Keep in mind every car is different when it comes to this particular conversation. I have swapped my rear gear 3 times now (haven't been out with the latest yet) and have found that what works for others doesnt work for me necessarily. My opinion is pick one to start with, then if you feel like doing the work swap to something else to see if it gets happier or not. Mine with a 28x10.5 slick has gone 163 through the quarter and I chopped it at around 1100 feet because it was feeling pretty loose with no spoiler and an el camino bed and such. My limiter is at 8100, shift light at 7500, and the light wasn't on......

 

[Outlaw Bill]

Gear the car to cross the finish line at what ever rpm needed and adjust the trans gearing to get the starting line ratio where you need it.

 

[cartruck]

This statement above might be the answer for some vehicles, it did not work for me however, proved to be very picky on track prep where it otherwise is not, and didn't pick things up as far as et and mph....... and I have swapped trans ratios more than once.

 

[Outlaw Bill]

This statement above might be the answer for some vehicles, it did not work for me however, proved to be very picky on track prep where it otherwise is not, and didn't pick things up as far as et and mph....... and I have swapped trans ratios more than once.

Do you have any kind of launch retard as in MSD grid?, Plus maybe the 1st gear ratio was still too much. Could be the suspension still needs work.

 

[cartruck]

I have a grid, I play with launch retard, it just made it so that if the track changed a little bit through the day it would upset things. I'm leaving with a 1.40 first gear too......

 

[63Futura]

This statement above might be the answer for some vehicles, it did not work for me however, proved to be very picky on track prep where it otherwise is not, and didn't pick things up as far as et and mph....... and I have swapped trans ratios more than once.

Thanks
This is what im after
I have no problem gearing it for 8k across the line but if its just as quick crossing the line at 7500 and can handle an average track better then id rather do that.
Just don't want to lug it down in top gear
We run a lot of boosted cars here (not many nitrous cars around) and they are all running 3.5/3.25 gears
And I have a Holley ECU to control everything so no problem there

 

[cartruck]

Keep in mind also that it's not a good idea to compare rear gear ratio's with the turbo guys when your on the hose. I can tell you that mine being geared up the way it is pulls the back half of the track more like a turbo car does, not sure if this is the norm for nitrous small tire, again, just what has worked so far for me. For reference I went from 3.70 to 4.11 and it went 1 mph quicker and a very very small increment quicker in ET on the one successful pass it made that day.

 

[blue ten]

What gearing are people running in the 1/4 with a 275 Radial and how fast ?
Done a bit of searching but everything these days is 1/8 not 1/4

What is your current set-up
Rear gear ratio?
1st gear ratio?
How much power are you making?
What are your time slips like now?
Are you logging any Data?
How much does the car weigh?
Too many variables to say "Run this gear for Low and this gear for the Rear"