Ultra cool FPS diff reinforcing (TOP SECRET)- Doug Lewis

[zach44102]

So way back when when i had my diff reinforced by doug at FPS I remember asking for pics of his work when I was told no, that he does not want his secrets and techniques out in the public. Well here are those ultra cool diff pics.

Not much secret here.

 

[zach44102]

Is this original drilled spots? or is this the so called drilling he did for more lubrication?

 

[kevinspann]

Not sure on the drilled holes, I'm too lazy to pull out the diff I have.

However: That ring gear has been off of that diff. It's put together with bolts instead of rivets. Not sure if Doug had to do that or not. If not, that trans has been apart more than once for sure. I wonder if it was shimmed well or not, to shred third like that.

Edit: I pulled a diff out and looked, those are holes that he must have drilled.

So at least he did what he said.

 

[Frisbeeguy]

I thought you just did that to the Gen 3's?

 

[zach44102]

Not sure on the drilled holes, I'm too lazy to pull out the diff I have.

However: That ring gear has been off of that diff. It's put together with bolts instead of rivets. Not sure if Doug had to do that or not. If not, that trans has been apart more than once for sure. I wonder if it was shimmed well or not, to shred third like that.

Edit: I pulled a diff out and looked, those are holes that he must have drilled.

So at least he did what he said.

Wow so this looks like to be a pretty beefy stock diff. The trans was shimmed so.... Idk if it was accurate or not but it was shimmed.

 

[Ishodu]

The drilled holes will help with getting **** to the center of the diff where the whole issue begins. But in reality those little tabs welded on there have no leverage to hold the diff pins in if the roll pins were to break IMO it would do very little at that extreme angle.

 

[zach44102]

The drilled holes will help with getting **** to the center of the diff where the whole issue begins. But in reality those little tabs welded on there have no leverage to hold the diff pins in if the roll pins were to break IMO it would do very little at that extreme angle.

Well I put the diff through ****. and the roll pins and diff pins are secure. He replaced the roll pins with hardened steel pins as well.

 

[rubydist]

the original pins are hardened steel roll pins too.....

 

[St Louis SHO]

The problem with the diff is not the roll pin. It is the way the spider gears rub the diff pin itself wearing it to the point of it welding itself. When the spiders spin and weld to the diff pin, it shears the roll pin and launching the diff pin through the case. IF he inspected the diff pins for wear, drilling the diff for more lubrication would be plenty to make it live.

OTOH. Welding to the diff pin is like trying to secure that wedge with bubble gum. Take a hammer and wack the weld at the pin. $1000 says it breaks off... Asked me how i know..

 

[intimdatr]

Why did he replace the original rivets with bolts?
Or i guess i should be asking as to why he had it apart??

 

[kevinspann]

The problem with the diff is not the roll pin. It is the way the spider gears rub the diff pin itself wearing it to the point of it welding itself. When the spiders spin and weld to the diff pin, it shears the roll pin and launching the diff pin through the case. IF he inspected the diff pins for wear, drilling the diff for more lubrication would be plenty to make it live.

OTOH. Welding to the diff pin is like trying to secure that wedge with bubble gum. Take a hammer and wack the weld at the pin. $1000 says it breaks off... Asked me how i know..

What this guy said. When I got my TYSHO diff ready to go in, one of the welds was loose. I had it rewelded, but I sure as shit don't trust it. A stock diff will be going back in this trans some time this winter.

 

[AREA 91]

Wow, I feel mutch better about my reinforced diff's out there.

 

[Phoenix]

Wow, I feel mutch better about my reinforced diff's out there.

Amen to that , it looks like it was welded by an apprentice.

Ring type reinforments ftw.

 

[Michelle]

It held up to some good abuse it sounds like, so I would say it has done its job.

 

[Vnuk1]

It held up to some good abuse it sounds like, so I would say it has done its job.

Agreed...

 

[zach44102]

It held up to some good abuse it sounds like, so I would say it has done its job.

My point exactly. About 60+ passes on the strip and not being affraid of the burnout box. About 15kmiles of DD, one wheels peels and mountain runs. I think its a pretty beefy stock diff. it did its job. im happy.

 

[LJRuddy]

My point exactly. About 60+ passes on the strip and not being affraid of the burnout box. About 15kmiles of DD, one wheels peels and mountain runs. I think its a pretty beefy stock diff. it did its job. im happy.

FWIW, I did this on my first MTX SHO with a completely stock diff and stock clutch. It held up just fine in the 60ish thousand miles I owned it too. Anything can happen.

 

[-DVP-]

FWIW, I did this on my first MTX SHO with a completely stock diff and stock clutch. It held up just fine in the 60ish thousand miles I owned it too. Anything can happen.

95? Broken pressure plate, I drove it 30 miles like that. Front tires were bald, rear tires were 90%... Car was driven hard to say the least. Trans still shifted fine on the way home. That thing is sitting in my garage as the spare.

 

[SHOtime2511]

I'm still wondering what is up with the bolts? better metal/surface to weld to maybe?

 

[LJRuddy]

95? Broken pressure plate, I drove it 30 miles like that. Front tires were bald, rear tires were 90%... Car was driven hard to say the least. Trans still shifted fine on the way home. That thing is sitting in my garage as the spare.

lol that was my second MTX. It was driven a lot nicer than the previous. Never did burn outs or spun the tires in the snow/rain. Front tires were bald as I was too broke to buy new ones at the time. In hindsight, that was a good thing as my ******* ex roommate blew the clutch later in the month.