Differences in Paul Guard Torqbias/Quaffe?

Brant · 11-30-2005, 07:21 AM

Another diff question.
I'm hoping Mr. Guard see's this thread, because I have the up most respect for his products.

but without calling him and personally bugging him.
Does the list have an opinion about the differences in the two different brands of Torque - biasing differentials?

does one brand weight more/less?
are they made the same, or is one using better technology?
does one style use better materials?

tia

Brant · 11-30-2005, 01:17 PM

Are they the same units then?
no production differences?

does anyone know?

JP, which did you buy and why?

brant

John Rogers · 11-30-2005, 02:34 PM

Well I am not an expert, but I have one of each. I noted the Quaiffe was NOT finished as well as the Guard, installation was about the same amount of time for my shop and to tell the truth I could not tell any difference when I switched transmissions. The biggest change I expected would have been under throttle out of a slow corner and they both make the car want to understeer so you better be pointed where you want to go. I use Goodyear slicks so I get a pretty good bite. One thing is they both generate some extra heat which is why I installed the pump and cooler.

Brant · 11-30-2005, 02:50 PM

thanks for the info John... I seriously do appreciate it.

let me ask one clarification question...
when you say;

" The biggest change I expected would have been under throttle out of a slow corner..."

do you mean change between quaffe versus guard
or do you mean compaired to an open diff.

I'm trying to figure out which brand of TB to get
brant

J P Stein · 11-30-2005, 04:24 PM

Brant:
As you know, I have 0 emperical data to add to any discussion about the pros & cons of the 2 different TB units.

About all I can do is regurgitate what Mr. Fordahl said.
He liked the Guard unit as he thought it was better built
and more well "finished". He also said that effect of transfering torque to the outside rear wheel (the more loaded wheel....which is why it's torque biasing) tended to make the car tighten it's line, thus you can get back OTG earlier.......which is about the opposite of what Mr. Rogers is saying. I went for what Fordahl said and bought the Guard TB unit.

So, once again we morons are left to the old "you pays your money & you takes your chances" school of car modifing.

Come April (or so), I'll have a better answer for you

Brant · 11-30-2005, 09:06 PM

JP,

cool..
thats good to hear that the guard unit is better made.
I would have assumed that but wanted to hear it before purchase.

believe it or not I did a little investigating since the thread 2 weeks back and am currently convinced that I want a Torq-bias style of diff over the ramp style/zf for TRACK use...

Not trying to start a flame war on my own thread....
just made up my mind after reviewing some actual data from a trusted source...

but like you say; "pays your money... take your chances"

Now I'm pirating my own thread aren't I...
back to topic. thanks again... Mr Guard it is then.

John,
I'm sure this is a repeat from your previous threads.
but one more question if you don't mind
seems like a clutch style would generate a lot more heat than open...

but why does the TB style generate so much more heat.
whats slipping in there.
I thought the unit was all gear driven with no slipping.
granted more gears than a stock open diff, but why so much heat.

(just so you know, I'm convinced on type of diff and brand of diff... but I'm still exploring the heat and trans cooling issue)

guess I need to spend some search time looking up your old threads.

brant

John Rogers · 11-30-2005, 09:34 PM

When I teach my computer classes, my disclaimer is "I am a software engineer" so I know some about hardware, but little. That applies to the dif in the race car too. They both work well I imagine and I have not put the Quaiffe through the same races such in Mexico with 1st gear turns so I can't say if it would heat more? I would be willing to rent out my two boxes for a "diff shootout" if someone would cough up the $$$$$$ to cover the costs of the transmissions, etc. Seriously, I think the Guard was much better built and I'm happy with it.

Brant · 12-01-2005, 06:27 AM

John,

thanks for taking the time to edumicate me.
I really do appreciate it.

I haven't had time yet to search out your trans cooling threads. (yet)

but did you have any data on oil temperature difference between an open diff versus either of your torq bias types?

brant

jluetjen · jluetjen's Garage

Quote:

Originally posted by Brant

I'm sure this is a repeat from your previous threads.
but one more question if you don't mind
seems like a clutch style would generate a lot more heat than open...

but why does the TB style generate so much more heat.
whats slipping in there.
I thought the unit was all gear driven with no slipping.
granted more gears than a stock open diff, but why so much heat.

Here's how I understand it in regards to diff heat generation....

* Coolest option: Spool -- because there are no surfaces rubbing against each other.

* Next Coolest: Open -- because while the gears are rolling across each other there is a minor amount of friction, but not much. When accellerating in a straight line there are no parts rubbing or moving against each other and so there is essentially no friction compared to a spool.

"Hot options"
* Plate type diff's (such as the factory style LSD) are open under minor load (depending on the pre-load) and generate heat as the clutches rub against each other. Under high load (depending on the ramp rates) the diff locks up and it runs very cool since it is then acting like a spool with no surfaces rubbing or moving against each other. In straight line acceleration there is no movement between the clutches and so there is no friction.

* Torque biasing diff's when open generate a fair amount of heat as the gears are moving against each other. Keep in mind the movement is a spur gear against a screw gear. This arrangement only moves when the screw gear is driving the spur gear. When the spur gear has more torque it doesn't move the screw gear. If there is any differential action quite a bit of heat is generated as the gears move against each other. This increases as the friction between the gears increases (as the diff smoothly increases the locking ratio) up to the point when the diff "locks" when the spur gear has surplus torque.

Obviously if Geary contradicts me, I'd go with what he says!

Brant · 12-01-2005, 10:55 AM

cool John...
thanks for posting on this.
seems like a constantly slipping clutch type (low ramp ratio) would create more heat than gears...

hmmm...
going to have to call my life line again to get some temp numbers.

bratn

Vintage911Racer · 12-01-2005, 12:43 PM

I use the Gaurd one myself.
No problems with Understeer. In fact, it turns very well. When you feel the back end start to slip, just give it more gas. It pulls you right through it.

You will get more tire wear. Meaning they will wear out faster in the rear.

Brant · 12-01-2005, 03:31 PM

ha.... not more tire wear than my locked diff I currently use...
but off topic again

Mark,
do you have any temp numbers to compair regarding GT versus Open on your tranny oil?

brant

KTL · 06:10 AM

Brant,

This is a good read

http://auto.howstuffworks.com/differential.htm

Tells you how the different differentials work in relatively basic terms. Good place to start learning about a LSD or T-B diff.

This one's pretty technical, but it gives a good description of what goes on inside a torsen diff.

http://auto.howstuffworks.com/framed.htm?parent=differential.htm&url=http://www.sonic.net/garyg/zonc/TechnicalInformation/TorsenDifferential.html

http://www.torsen.com/products/products.htm

Vintage911Racer · 12-02-2005, 07:20 AM

Brant, I do not. But I will tell you I have had no issues with heat in the box. I have run it in several 2 hour enduros with no problems.

I am also using Motul Gear oil. A bit off topic but I was told it helps to reduce temps in the tranny. I guess similar to redline gear oil.

Cory M · 12-02-2005, 07:25 AM

I've seen both disassembled side by side and the Guard unit appeared to be nicer with more detailed machining, I believe it was lighter as well.

Geary · 12-02-2005, 08:07 AM

Brant

I have sent out a few flyers to people who specifically ask to see the differences between the GT and Quaife Torque-biasing diffs. The differences are rather startling (but I WON'T be posting the photos on the internet).

The primary difference are that the GT unit is 2+ pounds lighter, and the internal machining is FAR superior.

Comparisons in operation between a TBD and LSD have been discussed ad naseum, and one only need do a search to find numerous discussions. But regarding the difference in heat generated between LSD and TBD, that's an interesting question. I don't know.

Keeping in mind that all locking diffs (as opposed to FULLY LOCKED diffs such as a spool) generate heat in proportion to the amount of work performed, my best guess would be that in a race of 2 hour duration, the oil would be heated an additional 20-30 degrees F with a TBD (over a plain open diff), and 60-70 degrees F with an LSD.

Brant · 12-03-2005, 10:46 PM

Quote:

Originally posted by Geary
Brant

I have sent out a few flyers to people who specifically ask to see the differences between the GT and Quaife Torque-biasing diffs. The differences are rather startling (but I WON'T be posting the photos on the internet).

The primary difference are that the GT unit is 2+ pounds lighter, and the internal machining is FAR superior.

Comparisons in operation between a TBD and LSD have been discussed ad naseum, and one only need do a search to find numerous discussions. But regarding the difference in heat generated between LSD and TBD, that's an interesting question. I don't know.

Keeping in mind that all locking diffs (as opposed to FULLY LOCKED diffs such as a spool) generate heat in proportion to the amount of work performed, my best guess would be that in a race of 2 hour duration, the oil would be heated an additional 20-30 degrees F with a TBD (over a plain open diff), and 60-70 degrees F with an LSD.

Thanks so much for the post..
I really appreciate the info.
and kinda backs up my theory that the LSD would create more heat. (personally, I don't want to add cooling due to weight of the pump and extra oil... if I can get away without)

Mark,

also good to hear that your not experiencing problems with temp on enduros. I'm going with a somewhat unique tranny set up that potentially will place more stress on parts of my tranny and want to avoid overheating as one more factor.

thanks all.
brant

jpachard · 12-04-2005, 06:42 AM

The issue of heat only comes into play if you plan on running longer races(1.5hrs +). I have a Guard ZF LSD and have had no problems with overheating the transmission during a 1.5hr enduro. Keep in mind that I also change my gear oil every 10hrs. and use Redline which has given me the best results as far as shifting goes.

Cheers, James

Brant · 12-04-2005, 04:06 PM

James,

we have one event annually that is over 2 hours.

brant

jpachard · 12-04-2005, 05:11 PM

Brant, I'm 90% sure you would be fine unless you are running at a very high ambient temp. ie 90deg F plus. Please feel free to e-mail me with any other questions at jachard at skipbarber dot com.

Cheers, James