Author Topic: Close vs. Wide  (Read 12110 times)

0 Members and 1 Guest are viewing this topic.

FElony

  • Guest
Re: Close vs. Wide
« Reply #15 on: March 07, 2018, 07:41:05 PM »
The weird thing is, if somebody has a wide ratio toploader and a 3.25 rear gear, nobody complains about it.   If somebody has close ratio toploader and 3.89 rear gear they act like it takes an act of Heaven to get the car moving, but both scenarios have the exact same overall first gear ratio.  Why is that? 

paulie

Could it be that the lower trans gearing makes the pinion climb up on the ring gear harder than the higher trans gear, which might raise the front end more, appearing to have more acceleration?

Barry_R

  • Hero Member
  • *****
  • Posts: 1988
    • View Profile
    • Survival Motorsports
Re: Close vs. Wide
« Reply #16 on: March 07, 2018, 09:06:47 PM »
More likely is that the guy who runs a 3.89 gear expects the car to accelerate off the light - the 3.25 guy knows its gonna be something of a puppy.  Perceived expectation...

Joe-JDC

  • Hero Member
  • *****
  • Posts: 1576
  • Truth stands on its own merit.
    • View Profile
Re: Close vs. Wide
« Reply #17 on: March 07, 2018, 09:25:25 PM »
Second gear, third gear don't feel as quick in the close ratio transmission because of the rear gears don't pull as hard with the 3.25 as the 3.89.  It is the final where the loss of acceleration changes regardless of what the initial equals.  Joe-JDC
Joe-JDC '70GT-500

plovett

  • Guest
Re: Close vs. Wide
« Reply #18 on: March 08, 2018, 07:09:31 AM »
Overall gear ratios.

Wide ratio with 3.25:
9.04/6.27/4.42/3.25

Close ratio with 3.89:
9.02/6.57/5.02/3.89

Rpms after shift with 6000 rpm shift.

Wide ratio with 3.25:
1st-2nd - 4165 rpm (53 mph) *with 27" tire
2nd-3rd - 4228 rpm (77 mph)
3rd04th - 4412 rpm (109 mph)

Close ratio with 3.89:
1st-2nd -  4371 rpm (53 mph)
2nd-3rd - 4580 rpm (73 mph)
3rd-4th - 4651 rpm (96 mph)

So your rpms at the shifts are going to be higher with the close ratio for more power (depending on the engine combination).  And your speeds will be lower.  So less air drag.  I think the close ratio will accelerate harder on the shifts, and accelerate the same on the launch. 

Feel free to check my math.  I'm in a hurry. 

JMO,

paulie





« Last Edit: March 08, 2018, 04:26:47 PM by plovett »

BattlestarGalactic

  • Hero Member
  • *****
  • Posts: 1296
    • View Profile
Re: Close vs. Wide
« Reply #19 on: March 08, 2018, 11:27:09 AM »
If you change rear gearing and change transmissions, yes the gearing works out.  But leave the rear alone and change transmissions.  That is when it all goes sideways.  That is when it feels like it won't get out of its own way.

2.78 x 3.25 = 9.03  (6.27 sec gear)
2.32 x 3.25 = 7.54  (gets close to sec gear of wide ratio) 

Even with my 4.56 gears in my truck it was a horrible feeling taking off.  Was not as quick....unless you can slip the clutch and hold the RPM up.   I would suppose with a lightweight, 3200# car it would not be so significant a loss?
Larry

plovett

  • Guest
Re: Close vs. Wide
« Reply #20 on: March 08, 2018, 04:46:38 PM »
Honestly for a street car, most of you guys are a bunch of pussycats.  How do you think guys back in the late 60's or early to mid 70's drove around?  There were L78 Chevelles with 3.55 rear gears, for instance.  Do you think they just couldn't do it?  It takes a good clutch foot to get an old musclecar out of the hole, but they could do it.  It's not like we're magically smarter than those guys.    You had to balance throttle and clutch and wheel spin.  While I've never had an L78 Chevelle , I've had 3.00 geared and 2.75 geared '69 Cougars with 2bbl 351W's and 3 speed sticks.  I think the first gear ratio on the 3 speed toploader is 2.99:1  so not a lot of overall ratio.  I could drive normally or fry the tires off. I never had to replace a clutch in tens of thousands of miles of driving.  There was no problem.  I feel like our perspective has changed to the point where we expect everything to be sooooo easy. 

JMO,

paulie
« Last Edit: March 08, 2018, 09:54:22 PM by plovett »

e philpott

  • Hero Member
  • *****
  • Posts: 1004
    • View Profile
Re: Close vs. Wide
« Reply #21 on: March 08, 2018, 05:08:48 PM »
.Close ratio box with 3.70 gear would wipe a Sof Loc clutch out in a weekend

FElony

  • Guest
Re: Close vs. Wide
« Reply #22 on: March 08, 2018, 05:37:28 PM »
.Close ratio box with 3.70 gear would wipe a Sof Loc clutch out in a weekend

I street raced a 428CJ (Fairlane) Cobra and a 429CJ Spoiler in the 80's, both with 2.32 first and 3.50 gears. Both had clutches that were already in there when I bought the cars. I pounded them hard. No failures. Maybe it's today's clutches that are garbage. When I see the move away from B&B Long to those phaggy diaphragm (GM-style) clutches, I know the end of the world is not far away. Gimme three fingers, baby.
« Last Edit: March 08, 2018, 06:02:39 PM by FElony »

gdaddy01

  • Hero Member
  • *****
  • Posts: 663
    • View Profile
Re: Close vs. Wide
« Reply #23 on: March 08, 2018, 08:30:04 PM »
I think it might have something to do with a 25 year old left knee versus a worn out 62 year old knee , that the doctors tell me the joint needs to be replaced in the knee and the nut behind the wheel could use some work also .

BattlestarGalactic

  • Hero Member
  • *****
  • Posts: 1296
    • View Profile
Re: Close vs. Wide
« Reply #24 on: March 09, 2018, 05:49:26 AM »
Honestly for a street car, most of you guys are a bunch of pussycats.  How do you think guys back in the late 60's or early to mid 70's drove around?  There were L78 Chevelles with 3.55 rear gears, for instance.  Do you think they just couldn't do it?  It takes a good clutch foot to get an old musclecar out of the hole, but they could do it.  It's not like we're magically smarter than those guys.    You had to balance throttle and clutch and wheel spin.  While I've never had an L78 Chevelle , I've had 3.00 geared and 2.75 geared '69 Cougars with 2bbl 351W's and 3 speed sticks.  I think the first gear ratio on the 3 speed toploader is 2.99:1  so not a lot of overall ratio.  I could drive normally or fry the tires off. I never had to replace a clutch in tens of thousands of miles of driving.  There was no problem.  I feel like our perspective has changed to the point where we expect everything to be sooooo easy. 

JMO,

paulie

Easy has NOTHING to do with it.   My ONLY point was the 2.32 is not an optimal first gear for performance driving, aka: drag racing.  If you want to road race, then fine, it gives you longgg legs in first gear which is great.  For drag racing, it makes it hard to be consistent.  Yes, back 40 yrs ago that was all there was.  3200# clutches, skinny bias play tires and peg legs.  Yup, it took talent to get them to get moving.  That has nothing to do with the conversation I'm having.

In drag racing, it is all about the combination of clutch, tire and traction.   They all have to work together and picking the most consistent one to slip.  Something HAS to slip.  With todays technology with clutches, sticky tires and the infinite possibilities of gear ratios there is no need to work with something difficult.  You mention changing rear gears to match the starting line ratio.  Fine, but you also gain a TON of finish line RPM which is not always doable.

Like I said, only the fact I went from a wide ratio to a close ratio, my starting line ratio went away and I didn't care for it.  It means my clutch(I run a 25 yr old Centerforce DF) has to slip more and I didn't like its manners for a 4100# truck.

My Nash is 3.25 first gear.   Do you think I could get away with a 2.32 toploader and have the car run the same?  Maybe, if I wanted to replace the clutch every few passes.  That ain't happening.  I get 2-3 yrs out of it currently.  Easier?  Ya, I guess.  Cheaper?  Definitely.
« Last Edit: March 09, 2018, 05:56:05 AM by BattlestarGalactic »
Larry

plovett

  • Guest
Re: Close vs. Wide
« Reply #25 on: March 09, 2018, 06:57:33 AM »
I imagine driving a 302 Z28 with a 2.20 1st gear and 3.73 rear gears would have been maybe the most difficult situation back in the old days.  A Boss 302 with close ratio top loader and 3.50 gears would have been easier, in my opinion.  I think the Boss 302's came with close or wide ratio, almost randomly.

JMO,

paulie

My427stang

  • Hero Member
  • *****
  • Posts: 4228
    • View Profile
Re: Close vs. Wide
« Reply #26 on: March 09, 2018, 07:53:18 AM »
I am not a close ratio fan in toploaders, unless maybe in small block road racers, but that is theory only, I don't do that LOL

I did run my Mustang from Vegas to Anaheim and out to Huntington Beach with a 2.32/3.70 rear/12 inch clutch/28 inch tall tire/433 FE with a P-sonic and a 250@.050 108 LSA solid Isky.  It made it, but notice what I did about a year after that run (489/5 speed/4.11 gears LOL)

However, all the guys with wide ratio sets in a C-6 seem disappointed.  It's hard to compare a clutch and solid drive to the gearing with a fluid drive because pre-stall, the torque converter adds torque multiplication

So drag racing, I would expect a wide ratio C-6 might do OK using standard SLR calcs assuming the ratio spread from 1-2 and 2-3 isn't wonky as a result of the deep first

However, on the street, my hunch is that the combination of the converter multiplication and the low gearset makes the low gear looser (lower) and the step from 1-2 more pronounced and in that case, therefore the wide ratio C-6  isn't as happy as a wide ratio Toploader.

Trying to make sense of it, but I haven't found a single car friend who dislikes a wide ratio Toploader and at the same time haven't found a single car friend thrilled with a low gear C-6.  Thoughts from the slush box guys?
« Last Edit: March 09, 2018, 07:56:45 AM by My427stang »
---------------------------------
Ross
Bullock's Power Service, LLC
- 70 Fastback Mustang, 489 cid FE, Victor, SEFI, Erson SFT cam, TKO-600 5 speed, 4.11 9 inch.
- 71 F100 shortbed 4x4, 461 cid FE, headers, Victor Pro-flo EFI, Comp Custom HFT cam, 3.50 9 inch

plovett

  • Guest
Re: Close vs. Wide
« Reply #27 on: March 09, 2018, 08:00:33 AM »
Well said, Ross.  Big difference between autos and sticks when it comes to gear ratios.  That's why I said the manual is much more sensitive in that regard. 

I didn't like my wide ratio C6.  In fact, sometimes I think less gear ratio can sometimes make an auto work better.  I think it can make the converter work better by putting a higher load on it. 

I like to tweak all you super low gear ratio manual tranny guys, but I get that it makes a difference.   It is funny though.  30-40 years ago, it was all close ratio this and close ratio that.  Now, it's all more ratio this and more ratio that.   I think catch phrases are just catch phrases and it's the specifics that matter.    I'll stand by my assertion that the close ratio toploader with 3.89 gears will pull harder in all gears than the wide ratio with 3.25's.  What bugs me is that as soon as someone hears "close ratio toploader"  they've already made up their mind that it's going to be a slug. 

JMO,

paulie

BattlestarGalactic

  • Hero Member
  • *****
  • Posts: 1296
    • View Profile
Re: Close vs. Wide
« Reply #28 on: March 09, 2018, 10:27:59 AM »
It will be a "slug" if you keep the same rear gears(apples to apples).  That is the problem and you have to take that into account.  You can tweak me all you want, but I know what works.   There is nothing wrong with a close ratio, but not for use in drag racing "today".  Not 45 yrs ago, today.  With today's technology.

You can run 3.25 gears with a wide ratio and get on the highway and cruise at much lower rpm.  Try that with 3.89/4.11's and let me know how you like it.  Yes, it might accelerate the same, but that is why everyone bitches about not having OD on the highway.  My truck has 4.56 gears and 29" tires and the 428 runs 3500 rpm on the highway.  Luckily I don't plan long trips with it, but I run the highway whenever the need arises.  It runs in the sweet spot and all I have to do it lean into the throttle and it runs away from traffic.

I agree, automatics seem to work better with less first gear.  Let the converter do the work.   Might build a bit of heat, but the cooler takes care of that.
Larry

Tommy-T

  • Sr. Member
  • ****
  • Posts: 332
    • View Profile
Re: Close vs. Wide
« Reply #29 on: March 09, 2018, 01:08:04 PM »
I am not a close ratio fan in toploaders, unless maybe in small block road racers, but that is theory only, I don't do that LOL

I did run my Mustang from Vegas to Anaheim and out to Huntington Beach with a 2.32/3.70 rear/12 inch clutch/28 inch tall tire/433 FE with a P-sonic and a 250@.050 108 LSA solid Isky.  It made it, but notice what I did about a year after that run (489/5 speed/4.11 gears LOL)

However, all the guys with wide ratio sets in a C-6 seem disappointed.  It's hard to compare a clutch and solid drive to the gearing with a fluid drive because pre-stall, the torque converter adds torque multiplication

So drag racing, I would expect a wide ratio C-6 might do OK using standard SLR calcs assuming the ratio spread from 1-2 and 2-3 isn't wonky as a result of the deep first

However, on the street, my hunch is that the combination of the converter multiplication and the low gearset makes the low gear looser (lower) and the step from 1-2 more pronounced and in that case, therefore the wide ratio C-6  isn't as happy as a wide ratio Toploader.

Trying to make sense of it, but I haven't found a single car friend who dislikes a wide ratio Toploader and at the same time haven't found a single car friend thrilled with a low gear C-6.  Thoughts from the slush box guys?

Like I said before it took me a while to find a place where the wide ratio kit shines. My car has 33" tall tires and 3.70 gears. With my blown deal I really have loads of torque at 3000 rpm up through redline. The high gear drop off in rpm works great in my application now as it drops right into a torque "sweet-spot".
Didn't care for the low gear kit when I was N/A.