10cjennings

iTrader: (1)

When I was looking to upgrade to a better LSD, I didn’t find much information on the MFactory clutch units, with most of the front running SOLO drivers I knew going with the much more expensive OS-Giken unit. I’m putting this thread together to show my experience/impressions with the MFactory 1.0 way clutch thus far and answer any questions.

I’d previously been running an MFactory Upgraded helical. That was a huge step up over an open diff. I’d also had plenty of seat time in a couple almost identically set-up cars running OEM diffs, and the difference in on power push was noticeable, even as this car was making a good bit more power. I had shied away from going with a metal plate LSD initially as I was worried about extra maintenance and poor street characteristics, as I was still street driving the car regularly (More on how wrong I was to come).

Install

First things first, let’s pull the trans!



At the same time, I decided to replace the trans. Here it is on its way home. They might have gone a little overboard on the blue bolt paint…but it was a good deal



Swapping over the ring gear from the EP3 unit to the MFactory…Note the integrated Speedo gear on the MFactory case. Those gears are very thin and often break when trying to pull them off the diff, so that’s a nice, headache saving addition. The LSD also comes with a replacement VSS gear for the sensor itself(I forgot to take a picture), but it easily installs with a C-clip.



The trans stripped down, cleaned and ready to be re-built.



LSD IN. With the new diff bearings it needed to be lightly tapped into place



Back together, ready for the halves to be mated



Another nice, unexpected addition. MFactory included a set of their magnetic drain bolts. The longer one is for the engine oil pan, and the shorter is for the transmission.





I purchased the LSD already set-up by MFactory to the 100% lock up setting, and the faster ramp setting. There are two ramp settings and an 80% lock up setting. I went with what MFactory recommended.

The Break in:

The MFactory recommended break-in procedure is as follows:
1. Fill the transmission with mineral oil 10w30 for break-in.
2. Figure 8’s for 10mins (Clutch disengaged while turning, Don’t exceed 15mph)
3. Figure 8’s for 10mins (Gently apply part-throttle while turning)
4. Full lock circles for 10 mins (To the left, part throttle)
5. Full lock circles for 10 mins (To the right, part throttle)
6. Drain fluid, clean drain plug.
7. Fill with Torco RTF and friction modifier

After that, just brush your teeth to get the vomit out of your mouth and you’re ready to race!

Driving Impressions:

I prefer numbers to some lengthy description on how much of a difference it makes, so it was really the PAX, Raw times, and data logs that put the difference the LSD makes into context for me.

With the only major change being the MFactory LSD, over the last 4 events the average RAW standing at local events has gone from 12th to 4th. PAX results have gone from 14th to 6th, and the car has had its first FTD.

We have a local club that runs the same practice course all year in order to provide good data on how changes are really affecting the car between events. Times on the practice course dropped by over a second. Using the Solo Storm data logger it became clear where most of this time was being made up, corner exit speeds. We are seeing increased exit speeds by 4-9mph with the clutch LSD vs the helical that was previously in the car.

Simply put, if you want to compete in SMF you need power (and this car is still way down on where it needs to be), and power quickly becomes more of a hindrance then a benefit in a FWD car that can’t put it down. The MFactory 1.0way clutch lsd allows the power to be put down much more effectively.

I’m trying to find a way to determine the differences in TPS inputs before/after the LSD but it’s clear that we’re able to get on the gas much sooner, and much more often.

Street Impressions:

I figured I’d throw this in there, this car isn’t street driven much anymore though. But when it was, the fear of a clanking lsd at every stoplight pushed me towards helical LSD. Simply put, with the recommended fluid (Torco RTF + Friction Modifier), I’m not getting any of that. The car drives perfectly fine on the street.

Durability:

I don’t have much to say on this yet, but will update the thread with this info. As of now, I’m thinking that with the limited seat time of a dedicated autox car, this diff won’t need any attention for several seasons, but time will tell. Even if it had to be pulled every year, the benefits of going with a clutch diff over a helical are well worth it. I loved the MFactory Helical I had, but in a race setting the clutch-type is a different animal.

Franshow

Sounds great Chris!! That MF LSD is the ****, the car was quick before but its a different animal now.

DVDr

iTrader: (2)

Great review, thanks for sharing.

MF lsd is in my books of future upgrades if I outgrow the stock unit.

Mr. Spade

Well written review.

I must say after doing work duty on your runs, the car looks a lot more tossable and has fellow corner workers saying Holy Crap whenever you slalom or go into a tight element. The car dances around elements like Michael Jackson on crack.

Also when we think you're going to understeer into oblivion, somehow you don't and actually put power down on corner exit.

Tyler Dirden

iTrader: (3)

What a good review. Just the sort of thing that makes one well informed by a proper user and break in.
The stats are impressive also. Congrats on the improvment.

Franshow

[QUOTE=Mr. Spade;49738754]

"The car dances around elements like Michael Jackson on crack."



LMAO hell yeah!

turntable teknik

excellent review!

10cjennings

iTrader: (1)

Thanks everyone. I'll update the thread with video footage when I have it.

ReDemoN

Well you pretty much talked me into a MF LSD.
Also you changed to a EP3 trans right? What is your top speed in 2nd now? Rev limit?
And why the choice of the 1.0 over the 1.5?

Xian

I was impressed with the MF diff in Billy's ITR powered EF the other weekend. My only gripe with it was that it had some much lockup that it could blow the tires loose pretty much anywhere. I suspect that running Hoosiers would "fix" that though.

solorex

Nice writeup, making me think twice about keeping the Quaife in there on my next transmission rebuild.

10cjennings

iTrader: (1)

I haven't done any testing to try it out, but that's probably where ramp speed and lockup settings come into play. I went with the most agressive settings because that's what MFactory reccomended based off the power I'm making. I believe the standard settings (at least for the k lsd) is 100% lockup and the slower ramp setting. Maybe 80% would better suit that car.

Yeah, the EP3 transmission tops out at 65 with a 23inch tire in 2nd at 8000rpm. I have a chart with all the k series transmission ratios on my computer that you can plug into those online transmission calculators. I'll post it when I'm on that computer. Another great thing is that they are way cheaper then the 6 speed units so you can sell what you have to get a 5 speed and the profit can cover most/all of the LSD.

I'm also running a k24 though. When I had the k20, the Z1 6 speed was pretty good, but with the extra torque and lower rev limit of the K24 I found myself shifting between 2-3 a lot.

And as far as 1.0 vs 1.5. Until recently I had always thought of 1.0 as the way to go in a fwd car and the 1.5 would just cause extra push. There was a discussion on here about using the 1.5 and then setting the car up looser, knowing there would be more off power push coming from the LSD and the potential advantages to doing so. Really, there just wasn't enough to convince me to try an out of the box approach in a car/setting where I wanted more off throttle rotation then most.