Spool vs. Diff
#1

OK, I want to make a comment about this. I see this mad rush to the spool diffs in pan cars. They do work but there is a * to that. They work in the right place with the right conditions, car and driver. I would encourage anyone that is new to not try running them until they now when all of those conditions are right.
I have seen racers run them because the allstar at their local track does and they are all over the place. It only takes one incident because you were running that locked diff to negate the advantage you had by running one.
To that all star, make sure you know the skill level of the racer before you suggest he run it. The worst comment is to tell someone is that "I see why you are slow, you are running a diff". Sometimes the diff is faster and I can tell you, ball or gear they are more consistent.
I keep all three available and know when to use them. Help others to know the same.
I have seen racers run them because the allstar at their local track does and they are all over the place. It only takes one incident because you were running that locked diff to negate the advantage you had by running one.
To that all star, make sure you know the skill level of the racer before you suggest he run it. The worst comment is to tell someone is that "I see why you are slow, you are running a diff". Sometimes the diff is faster and I can tell you, ball or gear they are more consistent.
I keep all three available and know when to use them. Help others to know the same.
Last edited by old_dude; 06-28-2018 at 01:56 PM.
#2

I totally agree.
#3

OK, I want to make a comment about this. I see this mad rush to the spool diffs. They do work but there is a * to that. They work in the right place with the right conditions, car and driver. I would encourage anyone that is new to not try running them until they now when all of those conditions are right.
I have seen racers run them because the allstar at their local track does and they are all over the place. It only takes one incident because you were running that locked diff to negate the advantage you had by running one.
To that all star, make sure you know the skill level of the racer before you suggest he run it. The worst comment is to tell someone is that "I see why you are slow, you are running a diff". Sometimes the diff is faster and I can tell you, ball or gear they are more consistent.
I keep all three available and know when to use them. Help others to know the same.
I have seen racers run them because the allstar at their local track does and they are all over the place. It only takes one incident because you were running that locked diff to negate the advantage you had by running one.
To that all star, make sure you know the skill level of the racer before you suggest he run it. The worst comment is to tell someone is that "I see why you are slow, you are running a diff". Sometimes the diff is faster and I can tell you, ball or gear they are more consistent.
I keep all three available and know when to use them. Help others to know the same.
#4
Tech Fanatic
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I started learning to race a few years ago. Nobody told me I needed a spool in the front. I saw that every other racer at the track was running one and decided I should probably go the same way. So I learned (from nearly the start) to use a spool up front. That being said I have tried both ball diffs and gear diffs. In my opinion and through my experience, ball diffs are slower under all but the lowest traction of conditions. I don't race on low traction tracks so the ball diff has no real place in my car.
#5

Is OP talking about pan cars or touring cars, big difference...
#7
Tech Prophet

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i was just wondering the same thing. I don’t think I’ve seen any one run a front diff in the small group I race with. I am kind of curious about these rear diffs for f1(Pancar). And I’m now seeing them for 1/12.
I just recently got a 1/12 Pancar. Haven’t really been able to run it yet. But I’m recently seeing that there are now diffs for them. Just guessing, but that could be a big change. And after last years rubber Tires discussion, I don’t get the impression that the 1/12 crowd is open to changes?
#10

I was never really into onroad much except for a little 1/10 pan car back in the day. On the Black CRC carpet, is there so much front grip in 2wd that the car still steers just fine with no diff? A few years ago ran a front spool on 4wd onroad with a ball diff in the rear and liked it and back in the day, around 1990 or so, ran an Optima Mid offroad with a ball diff in front and a gear diff in the rear. I never had good luck running a tight diff in pan car but that was on asphalt. These carpet tracks must really be different.
#11

The only good spool is a dead spool! No really if I had more diffs all my spools would be in the Landfill
#12

i was just wondering the same thing. I don’t think I’ve seen any one run a front diff in the small group I race with. I am kind of curious about these rear diffs for f1(Pancar). And I’m now seeing them for 1/12.
I just recently got a 1/12 Pancar. Haven’t really been able to run it yet. But I’m recently seeing that there are now diffs for them. Just guessing, but that could be a big change. And after last years rubber Tires discussion, I don’t get the impression that the 1/12 crowd is open to changes?
#13
Tech Prophet

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I forgot. Couple of your touring cars run front diffs. Once I made the move to belt drive from shaft drive, I kinda just got used to front spool. Think I ran them for few months before really realized there was a difference.
#14

1/12 spool versus 1/10th rubber tire spool is a massive difference.
1/12 was tougher to drive, even after adjusting the car to make it easier (softening springs all around). 1/10th rubber was not too much more difficult. This is just one opinion though...
My thought is setup a car that is easiest for you to drive, then once you are over 95-96% consistency (or top 5, 10, 15 laps at a tenth apart at most), start tuning and upgrading to new setups (spool, gear diff, motor, etc).
The ones I see who are crashing everywhere (less than 85% consistency) and think they need a new motor or gear diff......work on your driving.
1/12 was tougher to drive, even after adjusting the car to make it easier (softening springs all around). 1/10th rubber was not too much more difficult. This is just one opinion though...
My thought is setup a car that is easiest for you to drive, then once you are over 95-96% consistency (or top 5, 10, 15 laps at a tenth apart at most), start tuning and upgrading to new setups (spool, gear diff, motor, etc).
The ones I see who are crashing everywhere (less than 85% consistency) and think they need a new motor or gear diff......work on your driving.

#15

Ok folks I should have clarified pan cars. I did edit the thread start to show that.
I have seen the 1/12 newbees trying to run with a spool on their first run at a couple of tracks and it is hilarious and a little sad. I tell them to put the ball diff in and try it for awhile and they are immediately better. I let one track owner know that he should make sure they don't start with the spool. They will get discouraged.
All of my personal driving experience is with the rubber tire cars. At first it was good with the spool but it amplified some issues on corner exit and led me to fixing them with the chassis. Then once those were fixed I went back to the diffs and ran faster than the car with a spool.
I run a front spool 99.9% of the time in my awd car.
I have seen the 1/12 newbees trying to run with a spool on their first run at a couple of tracks and it is hilarious and a little sad. I tell them to put the ball diff in and try it for awhile and they are immediately better. I let one track owner know that he should make sure they don't start with the spool. They will get discouraged.
All of my personal driving experience is with the rubber tire cars. At first it was good with the spool but it amplified some issues on corner exit and led me to fixing them with the chassis. Then once those were fixed I went back to the diffs and ran faster than the car with a spool.
I run a front spool 99.9% of the time in my awd car.