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racerguy19
11-19-2015, 01:49 PM
Does anyone have first hand experience with using a welded diff on a fwd road race car??

Opinions welcome!!

Thanks,

Steve
Cornerstone Courier Racing
#54 GT5

terrydale
11-19-2015, 04:32 PM
Does anyone have first hand experience with using a welded diff on a fwd road race car?? Opinions welcome!! Thanks, Steve Cornerstone Courier Racing #54 GT5

"Poor Man's LSD"! :)

Been there, done that! On Minis way back in the 60's.

Huge pull to the right on acceleration; huge pull to the left on deceleration.

Manageable on an ice racer with less grip; downright terrifying on a road racer with slicks!! :eek:

I remember going through T1 once at Mosport way faster than I had ever been through it before after following Fritz Hochreuter in his Porsche through T10 and down the front straight way deep into T1 before realizing that I was going waaay too fast! Briefly letting off pointed me right at the guardrail Driver's Left so I kept it hammer down and drove through under strong acceleration. Terrifying - it took me a very long time before I tried it again on purpose..............but I did!! ;)

slucas
11-19-2015, 05:34 PM
But you developed arms of steel!

terrydale
11-20-2015, 07:27 AM
But you developed arms of steel!

And a couple of other things as well!!! ;)

23Racer
11-20-2015, 08:35 AM
"Poor Man's LSD"! :)

Been there, done that! On Minis way back in the 60's.

Huge pull to the right on acceleration; huge pull to the left on deceleration.

Manageable on an ice racer with less grip; downright terrifying on a road racer with slicks!! :eek:

I remember going through T1 once at Mosport way faster than I had ever been through it before after following Fritz Hochreuter in his Porsche through T10 and down the front straight way deep into T1 before realizing that I was going waaay too fast! Briefly letting off pointed me right at the guardrail Driver's Left so I kept it hammer down and drove through under strong acceleration. Terrifying - it took me a very long time before I tried it again on purpose..............but I did!! ;)

Slightly different, but similar experience in Turn 1. In the previous level of my RX7 I always did Turn 1 with a fairly big breathe down to the apex. As I felt the grip, the breathe would get smaller and smaller. I kept saying that the next session I would do 1 flat. Finally, the stars all aligned, the fuel load was low, the tires were hot, the track was grippy so I kept the throttle flat to the floor. Down to the apex, car started to unwind, yes... Yes... YES... OH GOD NOOOO!!!!!! Back end started to loosen, very quickly ended up almost full lock crossing the exit kerbing, the kerb hooked the rear tires and the car tank slapped 3 times going up into Turn 2. Always lifted a bit from then on, lol.

Eric

fastnx
11-20-2015, 12:52 PM
If you can get a proper clutch type limited slip it would be a big help. My car came with a viscous LSD stock and upgrading from that to a 1.5 way clutch type differential made a noticeable difference, it is so easy to drive. Going from an open diff to a limited slip would be night and day.

terrydale
11-22-2015, 10:02 AM
"Poor Man's LSD"! :)

Everyone knows I mean 'Limited Slip Differential', right?? :cool:

Signed,
Timothy O'Leary

racerguy19
11-23-2015, 02:20 PM
Everyone knows I mean 'Limited Slip Differential', right?? :cool:

Signed,
Timothy O'Leary

Ah ya....sure....we knew that....LOL!!

So if you had the choice of open diff or welded which would you choose??

Steve

terrydale
11-23-2015, 04:13 PM
Ah ya....sure....we knew that....LOL!! So if you had the choice of open diff or welded which would you choose?? Steve

Well..........the welded diff is a definite handful - don't get distracted or into a situation that you need to change your direction quickly and only have time to flick the wheel. You'll be meeting Robin and hearing all about her new truck real quick.

However, you will definitely chop chunks off your previous fastest laps compared to the open diff!!

I would really start looking around for an LSD - someone, somewhere, has one and there is nothing wrong with getting it used. The usual caveat when buying used stuff - especially from racers ;) - applies of course!

Steven Scala
11-23-2015, 05:22 PM
Might be worth mentioning other low-rent alternatives and their drawbacks, like the infamous 'phantom grip' (which I hear is effective for a very short amount of time), and the classic FF quasi-cheat of shimming the living daylights out of the diff.

This all reminds me, I should suss out what the diff situation is in the new iceracer. Hmmm....

terrydale
11-24-2015, 09:53 AM
Well..........the welded diff is a definite handful - don't get distracted or into a situation that you need to change your direction quickly and only have time to flick the wheel. You'll be meeting Robin and hearing all about her new truck real quick.
However, you will definitely chop chunks off your previous fastest laps compared to the open diff!!
I would really start looking around for an LSD - someone, somewhere, has one and there is nothing wrong with getting it used. The usual caveat when buying used stuff - especially from racers ;) - applies of course!

The added load on the drivetrain with a welded diff is very severe as well. Translate that to breakage - axles, cv joints, etc.

Its either 'full on' or................'FULL ON'!!! :eek:

23Racer
11-24-2015, 09:58 AM
For additional input. Terry, don't read the rest, LOL. A hundred years ago when I was racing Firehawk in our 100 hp Swift, we started the year with an open diff as per the rules. Even with only 100 hp, I was spooling the inside front tire coming out of 5 B at Mosport and at Shannonville, about every other corner. We tried all kinds of tricks like changing spring rates, alignment tweaks, etc... and we could reduce the issue but never eliminate it. We also saw that all the fast guys were using some form of welded diff or plate posi, so we had to get one for our car even though it was against the rules. Only one available was a Suzuki Sport 1.5 way Locker. Massive difference to the car. We could now pull out of corners as hard as the motor could pull with no tire spin. The car handled better under power and we reduced understeer as we could go back to some normal spring rates. Dropped at least a second off of our times.

Only negative was the one time we ended up on our roof in Turn 2 and when the car was rolled back on to its wheels, I was advised to return to the pits counter traffic so I had to make a U-turn to go back up the hill in 2. The marshal heard all the clacking from the cogs engaging and releasing and told me that we more than likely hurt the gearbox or halfshaft in the impact. I was all like, Yep, Yep Yep, your right I will get it checked out and tried really hard to keep the wheels straight until I could accelerate and have the noise drown out the clacking. Great benefit to that car and I assume to all FWD cars.

I have a Quaife diff in the Cougar and its smoother and the car has no torque steer, but it does do some odd things if you bash curbs.

Eric

terrydale
11-24-2015, 01:49 PM
For additional input. Terry, don't read the rest, LOL. A hundred years ago when I was racing Firehawk..............Eric


I have always said that the Series Steward only goes to the Year End Banquet in order to find out what really happened! :p

20+ years later is unusual..........but not a record!

Statute of Limitations, Eric! You're OK!!! And then again, maybe I'll have you do a Drive Through Penalty some day - just because! :D

23Racer
11-24-2015, 01:52 PM
I have always said that the Series Steward only goes to the Year End Banquet in order to find out what really happened! :p

20+ years later is unusual..........but not a record!

Statute of Limitations, Eric! You're OK!!! And then again, maybe I'll have you do a Drive Through Penalty some day - just because! :D



I would be laughing so hard if you did that. I more than likely would have to get out of the car.

I think that 25 years is long enough to wait, LOL.

Eric

racerguy19
11-24-2015, 03:03 PM
Steven and Terry, thanks for your input (and your drive down memory lane...LOL!). I've been pricing LSD's and by the time I get one to Canada and have it installed, I'm close to $2000. This is the whole reason behind the welded diff question.
The car I race is a 2001 Ford Focus sedan with a 2.0L Zetec. Last year I had no problem spinning up the inside wheel in a couple corners at Mosport. During the current winter break I will be installing a turbo on the motor which I'm sure will give me even more wheel spin. I'm not looking at monster boost, just enough to help me up the back straight.

Again, I thanks you for your input and knowledge on answering my question.

now the only question that remains is rob a bank or do an investment scam!

LOL!!

Cheers,

Steve

fastnx
11-24-2015, 03:05 PM
Sounds like a fun winter project. Are you staying in GT5? I was happy to see you out on a fairly regular basis this year.

23Racer
11-24-2015, 03:32 PM
Steven and Terry, thanks for your input (and your drive down memory lane...LOL!). I've been pricing LSD's and by the time I get one to Canada and have it installed, I'm close to $2000. This is the whole reason behind the welded diff question.
The car I race is a 2001 Ford Focus sedan with a 2.0L Zetec. Last year I had no problem spinning up the inside wheel in a couple corners at Mosport. During the current winter break I will be installing a turbo on the motor which I'm sure will give me even more wheel spin. I'm not looking at monster boost, just enough to help me up the back straight.

Again, I thanks you for your input and knowledge on answering my question.

now the only question that remains is rob a bank or do an investment scam!

LOL!!

Cheers,

Steve

Why don't you look in the wreckers for a transmission from a Focus SVT? They come from the factory with a Torsen diff that will do what you want. I bought a Zetec box last year for $300.

Eric

terrydale
11-24-2015, 03:34 PM
now the only question that remains is rob a bank or do an investment scam! Cheers, Steve

My advice on that would be to watch a couple of episodes of 'American Greed' on the History Channel. I've picked up a couple of pretty good ideas that would have worked with just a couple of simple tweaks!! :D

matbriand
11-24-2015, 07:26 PM
Why don't you look in the wreckers for a transmission from a Focus SVT? They come from the factory with a Torsen diff that will do what you want. I bought a Zetec box last year for $300.

Eric

This sounds like a much better option to me vs welded diff. Sometimes you want a little slip, if you didn't every race car would run a spool. It would be very hard on the arms and would be dangerous if used on a road track if you ask me. Ice racing with low traction is a different story.

Yes i know racing in itself is "dangerous".

metric1
11-25-2015, 03:07 PM
Hey Steve, buy the KAAZ diff. Stay away from Quaife and Wavetrac. Regardless of the hype, the are NOT racing diffs and will go open as soon as you bounce off the turtles or it gets wet.

racerguy19
11-25-2015, 03:40 PM
Hey Steve, buy the KAAZ diff. Stay away from Quaife and Wavetrac. Regardless of the hype, the are NOT racing diffs and will go open as soon as you bounce off the turtles or it gets wet.

Good to know, Thanks Ian!

Steve

racerguy19
11-25-2015, 03:42 PM
Has anyone heard about the MFactory race diff ?

Thanks,

Steve

metric1
11-25-2015, 04:03 PM
Helical diff. Same as the Quaife. They do have a plate type as well, about the same price as the Kaaz. Coil spring preload vs belleville washer on the Kaaz. I'd go with the Kaaz.

SlotMotorsports
12-06-2015, 08:47 AM
Message me , I can provide assistance or recomdations with your turbo setup and diff options. I would recommend staying away from welding, just bad news. The Quaife works great, I has never experienced a traction issue . Also keep away from the SVT trans, the parts are getting harder to find. The MTX75 is plenty strong , the 3rd gear synchro is the weak link but serviceable off season.

Bart