'85 Merkur XR4Ti Rally Car

Dude!  That is epic.

Seriously!  

I would have cut that damn thing off or just said berk it and bought a new one.

Well done.

The first thing that needed to happen this weekend was changing Chief's front brake pads- which wear out every 15k miles like clockwork.  I felt like a doofus having the lift occupied for this, but at least Chief can squeeze in so that I can close the door:  

Then it was back to rally car stuff.  The strut housing that I bashed the insert out of needed to be retapped, which was sort of a moment of truth since if the hole was blown out past 10mm then I spent hours ruining the end of that insert for nothing:  

Success!  The threads retapped nicely, since the ones on the insert were softer than the steel the housing is made of.  Then I cleaned out the old grease and dirt from the housings, using nasty chemicals and my special "rag duct taped to scrap steel" high tech rally strut tool:  

Then I did the "wiggle and look for less than .003" test John mentioned on the last page- and both struts have between .004 and .008" of play in them.  I'm waiting for responses from a few people to determine what my next step is there, since at this point I need bushings for both as well as a new rod for the one insert.  

Next, I put the turbo and remaining miscellaneous lines on the engine while Sara reassembled the front subframe:  

Then yoinked the transmission, clutch, and flywheel from the old engine:  

Hoisted new engine onto subframe:  

Put the clutch and flywheel on that:  

Put the transmission on that, got dollies under it, wheeled the hoist away, and took a blurry awful photo because damn that transmission is heavy and the fat 10 spline input sucks to align while you're holding it:  

Rolled the whole business under the car, not because I'm going to put it in yet but because I've never had the luxury of a lift for installing an engine/trans combo and looking at it makes me happy:  

Then, on our new workbench which Ian F retrieved from his neighbor's curb and delivered to us (thanks Ian!) I pulled the Supra LSD apart again:  

I had been waiting for Weir Performance to get back to me about their preload kit, but after emailing and calling a couple of times I was getting nothing so I decided to see what I could do on my own.  This LSD, assembled with the plates stacked correctly, has a breakaway torque of about 75 ft-lbs, and supposedly the ideal number for a heavy rwd rally car is somewhere around 200-250 ft-lbs instead.  

First, I made some assumptions- I assumed that the spring in the middle of the LSD is linear, and that its' relationship with the clutch packs is such that the breakaway torque increases linearly with spring force.  This means that, if I can shim the spring appropriately (and my assumptions are right or close to it), I can get whatever breakaway torque I want.  So, I went to my favorite racing parts retailer, also known as Tractor Supply, to acquire some shims:  

These bushings are almost exactly the same size as the base of the spring, and I bought the 6 pack of 14ga as well as a pair of 18ga (for fine tuning) for less than $4.  The kit I was trying to buy previously cost $75, for reference.  I knew from measuring the amount of spring preload that I needed about .330" of spacers in order to achieve just over 200 ft-lbs of breakaway torque, so I stacked 4 14ga bushings and an 18ga to get this:  

A quick check of the spring seems to indicate it won't hit coil bind when I assemble everything, so I dropped my shims in and bolted  the LSD unit back together:  

I don't have a torque wrench that goes to 200+ ft-lbs, but the breakaway is beyond 160 ft-lbs and I can just barely get it to slip with a bigass breaker bar so hopefully I'm in the ballpark.  I stopped here since I want to clean everything really well when I put the diff back in the housing, and cleaning things really well is better "beginning of next weekend" work than "holy berkeley I'm tired" work.

I was not aware that Tractor Supply had such a selection of "racing parts".  This is good to know!

Great score on the work bench....the patina is perfect!! You've set the ring and pinion 'lash' before I take it? Tractor Supply is a remarkably resourceful establishment.....probably don't go as often as I should. 

759NRNG said:

You've set the ring and pinion 'lash' before I take it?

Yes, but I'm not changing anything that has to do with the positions of the gears so it should go back together and be the same without me having to change anything.  In theory.

Very nice, I wish Tractor Supply had stores near me....

In reply to ¯\_(ツ)_/¯ :

If you’re going through brake pads on a Suburban every 15k, something is not right with them. You might want to check your calipers for drag, etc. 

I’ve owned three of those wonderfully oversized wagons, and I’ve never had one go through a set of brakes that fast.

In reply to Recon1342 :

I thought the same thing a while ago, and replaced the calipers, lines, and hardware- and it has continued eating pads at the same rate.  The roads around me are twisty and lots of the miles on this truck are done with a trailer, so I guess it's not that crazy, and the pads are cheap and easy anyway.

I would bet even money this is a "driving style" issue. 

In reply to mazdeuce - Seth :

That too... it has the police pkg sway bars for a reason!

Can you say 'left foot' braking......I knew that you could

Suburbans are under braked from the factory, and as a result they eat brakes if you don't drive like a grandma

The front strut inserts are on their way to Delta vee in Michigan for rebuilding- since they're old 41mm units, if they need anything super expensive I'll be developing my own struts using more common 40mm escort bits.  Fingers crossed that they don't need much so I don't have to do that (although I kinda want to see if I can).

Not a lot got done on the car this weekend, unfortunately.  It really only got worked on this afternoon, but we put the new (ancient) workbench to good use rebuilding a pair of axles, which I have no photos of because axle grease and cameras don't mix.  It went pretty smoothly with Sara cleaning the components and me reassembling with fresh grease and boots.  Here's the bench after degreasing all the tools:  

The diff also went back together, and now has the adapters bolted up- they still have masking tape on them since I didn't want to paint the contact surfaces.  Since we had issues with drivetrain fasteners vibrating out in the past, the axle adapters have both serrated flange nuts and loctite, and the driveshaft adapter has nordlocks and nylocks:  

In reply to ¯\_(ツ)_/¯ :

Red paint and green wrap..... Looking all Christmass-ie

Is that truly your tool box in it's entirety sitting on the grosh floor????

In reply to 759NRNG :

Yep, full of only the finest Harbor Freight crap.  Obviously I have some power tools too, but pretty much all of my hand tools are in there- I've never been a fan of big tool boxes.  That little box has taken apart and reassembled more cars and motorcycles than many people will ever own; sometimes I need to get creative but four drawers worth of tools is enough for almost anything.

In reply to ¯\_(ツ)_/¯ :

Agreed on the tools. I’m one of the senior mechanics at work, with one of the smallest boxes- a four-drawer rollaway with a five drawer box on top. I can accomplish quite a bit with a handful of wrenches...

I am at least partially responsible for the lack of rally car productivity this weekend.  Chris used Chief to help me get a vortec 350 for the Roadmaster.

Not just any Roadmaster- a manual swapped, hearse suspensioned, conversion van wheeled, all terrain tired, limited slip differentialed Roadmaster wagon.  Which needs a thread.

¯\_(ツ)_/¯ said:

Not just any Roadmaster- a manual swapped, hearse suspensioned, conversion van wheeled, all terrain tired, limited slip differentialed Roadmaster wagon.  Which needs a thread.     

Amen, the sooner the better!!! Chris, you may have already stated this before, but what are you looking at hp/lbft with this new bullett(rally car)???

In reply to 759NRNG :

The new rally car engine?  In theory, it should be in the ballpark of 230hp/300lbft but I'm not really shooting for a number.  Throttle response and area under the curve are more important than peak numbers for this sort of thing.

The new Roadmaster engine... no idea, but even a totally stock Vortec 350 (which is what Chief is pooping out in the photo) should be pretty exciting compared to the old bone stock engine with its' tiny cam and silly little ports.

Sorry the Merkur.....never was really all that  saavy on these motors...so obviously a way flat Tq curve is the desire, and no it's not a sillylittleportturbo'd go fast thingy 

Out of curiosity, are you intending to make WMWR this year, assuming snow?

In reply to irish44j :

I think the limiting factor will probably be the struts- if I have the car together by February I'll probably go, but I'm not sure that's going to happen.  I'll be happy to crew if I'm not racing.