It seems our racing has gone from 100% 1/4 mile to a good 50/50 between the two also including some 1000'.

Our cars are obviously geared to run 1/4 mile and I'm thinking of changing the gear for some upcoming races both cars have 35 spline 9" so it's an easy test.

The truck is the first on the list, it's got 4.56's and a 31" bias tire, it crosses the 1/4 at about 6900ish @ 133-134 mph, I wouldn't be scared to go 7200-7300 so I feel even at 1/4 mile racing I'm leaving a bunch on the table, leaving a ton in the 1/8. Problem I see arising with that combo is my kid is leaving at 2100 to go deep, add more gear he's gonna have to back off, not sure how much more room we'll have footbraking ?? Maybe shallow is possible ?? I was thinking of trying 5.13's. I doubt we could make a full pull in the 1/4 but we have a restrictor plate on that if we needed to kill a little to get by.

Firebirds a different story though. Leave at 2600 ish deep and go through at 7300+. It's only got a 4.30 gear but go's 140+ in decent air. Maybe the trucks 4.56's might work in the 1/8 but would that little change be worth the effort ??? I think with the small radial tire we're limited to the 4.30's, no room under the hood for a restrictor plate either.

For the record, both cars repeat very well in the 1/8, but both 60' very weak considering the et's. Firebird will always be a deep car as it's on gas but the truck on alky is close I think to possibly being able to go shallow.

What gear/tire dia are you strictly 1/8 mile guys running ???

What's your experience with gear change effecting reaction times ???

I'm looking at solid .57 rear gear change, just wondering what to expect ..............



Thanks !!!!!

4.56 in the truck the converter is slipping 6-7% crossing 6900 rpm.

It'll cross 7300 rpm 5.13 slipping 3-4%

What size tire is on the Firechicken?

Firebirds got a 29.5x10.5

quote:

Originally posted by HS professor:
Firebirds got a 29.5x10.5

You could do a 4.56 in the Firebird and cross the same rpm you are now + - 50 - 100 rpm.

How many times a year are you WFO at the stripe? I rarely ever was Super Pro bracket racing, and I rarely chased anyone.

I would leave the current gear in the car.

The cost VS gain has a really poor ROI. If you look at your 660 to 1320 speed and RPM increase in most cases it's a lot less than you think. Depending on the car it's rarely more than 38 MPH. Of course there are some exceptions but on average it's less than 38.

The downside can include the initial hit, that might negatively effect the consistency. Another individual factor can be the converter slippage rate at 660 feet vs 1320 feet.

The cost of a new gear set (or a complete second third member) plus the time involved in swapping them isn't worth the money, or the time. The older you get, swapping the gear set several times a year becomes less appealing.

If you need to go faster buy a blue bottle, that will give you a boost at either distance.

Don't be too concerned about the 60 foot time, the race doesn't at 60. Sometimes a weak 60 and a strong finish line speed have an advantage. As for the reaction times: If you are racing on anything but a Pro Tree it really shouldn't matter, you're working with a 3 amber full tree. The key to you post is that both vehicles "repeat very well" it might be a challenge to regain that consistency with a lower gear change.

Just my 2 cents:

Bob

It's a no brainer if you have a 9 inch. When I came back in 2017 to do some hot rodding. I had 3 different low gearsets 1.80, 1.64, 1.69.... 4 rear gears 3.89, 4.56, 4.88, 5.00... two carbs 4150 - 4500 ... two intakes 4150 SV2 4500 SV2 ... and 3 different converters in my car in 12 wfo laps.

All 12 were good laps. It's not how many you make per time you go to the track, it's how many good ones you make, in order to access changes.

Too bad they made it so blatantly obvious , they weren't down with getting filleted again.

It's a shame

Come on Mike

Don't start with that shyt

quote:

Originally posted by HS professor:
Come on Mike

Don't start with that shyt

I'm a little angry with liars and cheats is all. Might be this corona hoax.

It seems the lefty's are taking over. It's a shame people of good conscience don't stand up to freaks.

We wouldn't be having these problems with Lefty freaks. Had they every single time these freaks raise their ugly heads.

quote:

Just my 2 cents:

Bob

Thanks for the input Bob.

I'm not worried about traction in either car or worried about going faster, I'd really like to be able to shallow stage the truck and not change the way we see the tree. 4.56 to 5.13 is a pretty big swing, I'd love to hear what people have experienced from this change reaction time wise.

If the swap is worth .01 to.020 on the tree, it may not make sense ........

I'm not a liar or a cheat and I'm as red as they come so please

Stop that shyt

You give some good info, so lets keep it at that.

quote:

Originally posted by HS professor:
I'm not a liar or a cheat and I'm as red as they come so please

Stop that shyt

You give some good info, so lets keep it at that.

You're red? What are you in a gang?

I'm as conservative as they come. If people of good conscience had stood up every single time these freak lefty's raised their ugly heads,as the founders suggested, we wouldn't be having these lefty freak corona hoax problems, now would we?

Lying and cheating freaks got a grip on it now, don't they?

Oh well, we'll reap what we sow right? Karma right?

quote:

Originally posted by HS professor:
What gear/tire dia are you strictly 1/8 mile guys running ???

4.40 / 32x14 ….. 1.49 / 6.3x @ 112 I prefer slightly more mph than the et.

HS, can you not leave at a higher RPM for reaction time increase?

I run a 4.71 rear gear, 1.80 trans, 1.30 60', 5.90 in heat @ 116. 2750#. 14.5x32 tire.

I run this 1/8 and 1/4. I have never ran it wide open in 1/4 only on the stop. it goes 10.90 at 141 crossing at 7500 in good air and 7300 in crappy air.

i ran a 5.13 gear with a stock trans years ago and it was done at 1000 feet 1/4 mile and only making noise. the 4.71 will pull to the end.

ep-current engine is 427 and old engine years ago was a 406 iron head engine. for what it is worth

quote:

4.40 / 32x14 ….. 1.49 / 6.3x @ 112 I prefer slightly more mph than the et.

That's very similar to the Firebird

I ran it last week and it went 1.50 deep staged 6.37 @ 110. It usually goes 111/112 ish but it was 100 degrees lol

What rpm you go through at ???

Ya'll are hussling people out of win lights, is what you're doing!

quote:

HS, can you not leave at a higher RPM for reaction time increase?

To a point yes, but it seems to hit a point where rpm has little effect on reaction time.

One track we frequent is very, VERY tight for deepstaging only. Something to do with beam height and a starting line crown. Problem is cant leave low enough deepstaging to be green and cant leave shallow without being better than .060. It's close too, usually teen to .00 red deep. Very frustrating ............

This is all footbraking

I changed from 4.56 to 5.13 with 29.5x10.5 tires because I couldn't get better than .545 reaction time shallow. After the change I can now go red shallow. I say try it if it works you don't have to be worried about getting in DEEP.

Bob, please don't take this as a slight in any way but I have never understood why people have to deep stage. They haven't allowed deep staging around here for 25 years and I see people racing 10 second 1/8 mile cars having no problems on the tree. North and East it seems lots of people have to deep stage. Just strange to me is all.

There is one guy who races a Ford dually in Sportman that has been track champ a few times and he hits it shallow.

I understand about getting to a point where RPM doesn't help though. When I'm running high gear only after about 3600 it doesn't change for me.

quote:

I changed from 4.56 to 5.13 with 29.5x10.5 tires because I couldn't get better than .545 reaction time shallow. After the change I can now go red shallow. I say try it if it works you don't have to be worried about getting in DEEP.

That's the information I was hoping for !!! If I can get close to that I'll be good. Thanks !!!

quote:

Bob, please don't take this as a slight in any way but I have never understood why people have to deep stage.

Trust me Curtis, I wish we didn't have too, it truly does su ck, I hate it !!! Big disadvantage to us. Vehicle weight and front end travel are probably the biggest culprits. A .500 pro tree tells the story ...............