Back to the Future-Ron and Sydney's 1985 5L Mustang Build

Ron Earp

I've been off for many years doing lots of things, mainly racing. Last year I managed to win our SCCA SARRC points racing series with my SCCA ITS Mustang. So this year I'm talking a bit of a break and doing other projects. Good thing too, because my daughter turns 16 in several months and she'll need a car. Which starts this build thread. I'm a few weeks late bringing it to this forum but it is still early.


A long time ago I had a car. It was a pretty cool car for the time, a 1985 Ford Mustang 5L notchback. Notchbacks, or more properly sedans, were fairly uncommon being out produced around 10:1 by the hatchback/GT cars. This particular 1985 sedan was unique as it had all the LX trim options, power windows, "good" stereo, trim, and it had all the go fast goodies from the GT - 5L HO carbed roller cam V8, SS tubular headers, better shocks, springs, bars, and the Goodyear Gatorback tires. Even better it was lighter than the hatch cars.

Our family was the second owner of the car, acquiring it in 1986 with about 7k on the clock. The first owner had painted a matte black stripe down the hood to make it look like a GT. Here it is back in the day.


I drove the car from the late 86 time from up until around 1994, so about eight years, and covered around 140k in it. The car was bulletproof - fuel, oil, sparkplugs, one water pump, and brake pads/shoes were the only consumables.

Lots of stuff happened in that car, way too much stuff to cover here, but I did have it when I met my wife and she also traveled many a mile in the old five oh. It went to NY, PA, FL, SC, TN, VA, OH, GA, WVA, generally carrying four folks on some sort of road trip. All I know is when I remove the interior my daughter won't be present.

In 1994 my then girlfriend, now wife, drove it to Ohio to visit the Air Force Museum. Along the way the engine overheated and developed a pretty nasty ticking sound, but, we got there just fine. Once there we visited the museum we got hit on the right front quarter by an uninsured driver changing lanes into us. We nursed the car back to Virginia but I was scheduled to take a job with Dow Chemical in Louisiana inside of two weeks, so, the decision was made to sell the car.

This picture is from the day I sold the car, notice that the front emblem is missing. I liked the car so I did two things, took a rubbing of the VIN and took the front Ford emblem. Dude who got the car asked me what happened to it, I just shrugged and replied I had no idea, must have flown off last night on the way home.


That Ford emblem has traveled all around with me since that day and can always be found someplace in whatever I have as a workshop. For the last fifteen years it's been attached to a TV in my garage, here it is today.


Now over the last few months I've been contemplating a car for my fifteen year old daughter Sydney. She likes cars, and I'm determined to use my car skills to provide her with something memorable. We've been talking about projects on and off, I'd like for it to be some sort of hands on experience, and about the best I've come up with is a few restorations or creating something that doesn't exist, like a manual tranny Jaguar XKR or similar.

Then one day I was fishing around in my old watch box I found the old registration for my old Mustang. That was it, I knew what the project had to be and set off looking for the car which is detailed here I'm looking for a car I used to own...

And here we are.

So the car has been owned by the same fellow in Mebane NC since 2009/2010. He received the car as a gift for work he was doing on another fellows car, basically a trade arrangement. When he got the car everything worked - AC, windows, etc. and his wife used it to commute back and forth to Burlington. Around 2012 the rear main seal began to leak and the transmission was hard to get into third, so, the car was parked under a cover. January of 2016 the fellow uncovered it, moved it back into his garage, and began to get it back in working order to sell. They've got five kids, want the project out of the house, so when they got my letter in the mail looking for the car they were happy to give me a call about it.






It needs a lot of work but mostly it is all there. He has dash parts, all AC, etc. everything it appears to making it a driving car again. Just needs a lot of work. I'm not sure exactly what the plan is, except to pick it up weekend after next and it's going to occupy the place where my green ITS Mustang resides.

So, it's on.

Ron Earp

The green ITS car has been gone through and prepped to live on the trailer. It could be unloaded from the trailer to the race track with nothing but a tire change and will probably be used at the Feb Tarheel Sportscar Club event. It's not being sold, heck, you can't get a can of beans for an ITS car.

This is the weekend for car retrieval. Should be a good one.

I found another picture of the car from it's time in VA. It's being overshadowed a bit by me showing off my new scoot.


Ron Earp

The car has been retrieved and is in the shop. Jeff G, Sydney, and me rolled down to pick it up yesterday. When we arrived the family had already pushed it out of the shop.


Loading, it took a village. Fortunately the previous owners were fruitful and multiplied.



Happy new owner


The car came with a few go fast goodies that can be sold to bring the purchase price down a bit: aluminum driveshaft, 8.8" rear end with 3.55 gear, tubular subframe, camber/caster plates, two ally intakes, two carbs, and some other odds and ends.

Our paint guy Fred will visit this weekend and I hope to have the interior stripped before that visit, and by the end of the weekend the engine bay cleaned out. From that point it'd only be six to ten more hours of work before it'd be ready to head to the paint shop.

Ron Earp

Plan made and interior stripped less dash and doors. She liked the chart idea of planning the project and might have learned something valuable there.







Ron Earp

Some progress. Went to the Mustang Parts Superstore, aka, the storage space above the garage, and brought down two damaged transmissions we got from Dave Brown, Ford Guru Extraordinaire. We've got a lot of storage space above the garage, and a winch, but getting up there is a bit challenging for those of us that are vertically challenged, my daughter and I both. The stairs have almost kicked her ass more times than I can count.


We took apart the original box that was in the car. The PO indicated it was broken, but near as we can tell its in decent shape. It has damaged shift forks, a bit of an abrasion on a third gear tooth, but certainly serviceable. Sydney got the hang of the air tool and we took three boxes down to their component pieces with the help of Jeff G who helped out in the middle of the process.


The box shown on the left, the dirty one, is THE ORIGINAL box, the one that turned the wheels of the chariot while I ranged around the greater NC area.


The Dave Brown boxes are mostly toast but between the three we've got a good set of gears, countershaft, main shaft, and housings. We plan to build the new box using one of the later housings (the original box has the funky T5 reverse spring), and will stick with the 0.68 5th gear set instead of putting a better V6 0.73 5th gear in the box. We'll be using the 3.55 gears in the 8.8" axle so we might need a highway gear.

Ron Earp

We made quite a bit of progress on Saturday. Sydney and I tore the engine down and it was an educational experience for her. She learned a lot about using tools, and of course some understanding of how engines work. Not that she needs to know that since we'll all be in electric cars within 20 years. But it's about the journey, not the destination.




The engine is in good shape for a rebuild. My guess is the PO disassembled, cleaned it up, and put it back together with new bearings and rings. Not exactly a rebuild but it would have run well enough. He might have used a dingleball hone on it but it's difficult to tell. We're going to take it down to the machine shop for a full checkout of all the round stuff. Once done we'll reassemble. I've got a set of new aluminum heads on the way for the build and plan to order a Air Gap intake.

Sydney headed out for some other activities while Jeff and I continued work. First on LeChump where we pulled the motor out of it for inspection from its failure last weekend at VIR. Munched bearings. Then we put the notch on the lift and started disassembly of the front and rear suspension. I'm hoping we'll finish that up later today.

I bought 2" square steel on Friday so that we can make a dolly for the body. Once the car is completely stripped it can sit on the dolly for blasting and paint.


Ron Earp

I've been away on some business travel but we have been making progress. Just haven't had time to post.

One item of business that needed tending to was a high-quality dolly to roll the car around on. Jeff G and I welded this up in a few hours while Sydney was at jazz band rehearsal. Naturally we had to put in on the scales and once you remove externals weights from the calculation the tub will weigh about 1000 lbs.






The dolly is nicely done and rolls well. We added some small square steel tubing to locate it fore and aft. It can't slide off now and we also welded on some loops for tie downs. I need to give it a quick coat of paint.

Stripping of the car continues and we are now down to the the last remnants. We're off to paint this weekend.




I've got a Ron Francis 1985 Mustang specific wiring harness headed our way to replace the hacked up factory stuff. 60% of the factory wiring will not be used (emissions, external voltage regulators, more emissions) so I think this is the way to go for a neat, simple, and reliable harness.

Meanwhile, the 8.8 was rebuilt and "detailed", meaning it got degreased, painted in primer, and then in chassis black. We installed the torsen and kept the 3.55 gear set.


Gear pattern came out very nice, nicer than any we have setup for the race cars.


And wiring stripping continued while rear end work was happening.


Sydney making some progress on the wiring.


And we are getting closer to having the tub stripped. We lack the doors and a few odds and ends.



Ron Earp

Work continues. Interior stripping was completed with the door panels. Transmission rebuild is underway, and the rear end is finished. The 8.8 I scored came with one of those TA covers that preloads the bearing caps. I'm sure it is overkill for this application but it looks sexy. It does have drain plugs which is a nice feature. Tranny rebuild will happen today and I also plan to get after port matching the Air Gap manifold with the low buck ally heads I decided to try.




Randy V

Staff member
Lifetime Supporter
What a cool thread this is.... Projects like this with our children are the very best!
Yes - It's about the journey!!! :thumbsup:

Ron Earp

The car is headed to our painter tomorrow so we had some final prep to finish up. The back seat brace had broken free from the chassis so we needed to weld that up. Good opportunity for Sydney to learn a new skill so I put her to work. After showing her how to do one she did alright. Made a few mistakes, but that is how you get experience.

Suited up

She did the prep on the piece and learned most of welding is prep.

And a bit of spot weld repair getting done here.

And the rest of the time was spent removing last minute trim pieces and taping up items we didn't want painted.

Meanwhile, over the weekend, the gear box was rebuilt and is ready to go.




Ron Earp

Thanks for the congrats with the Father/Daughter project. So far it has been working out pretty well. At the end of the day it isn't about a specific skill she learns, but more about confidence she might develop to complete any project that she decides to tackle. My dad didn't race or restore cars. He repaired cars regularly, as many needed that in the 60s and 70s, fixed anything around the house including building additions etc, and offspring were fully expected to help. He had hobbies of course - electronics/ham, aircraft, shooting sports, radio control, and we took part in all of those as well. The main thing we learned is you can do anything you want to do if you fully engage yourself.

The chassis went off for paint last week. The dolly got high remarks from the paint guys and they want to buy it. Hoping the car is back in about a month.


Ron Earp

Thanks LKQ for propping up all the Mustangs with a wheel so that the trunk floor can’t be harvested from the car. Yay. The 85 needs a new spare tire well, which I was aware of, but I had no idea that it’d be a bit difficult to obtain one. At least, difficult to get on a trip during my lunch hour with a sawsall, drill, and no jack. I’ll be back with more tools.


Ron Earp

Off at the beach for some R&R but before leaving all the parts came in for the engine build which will commence on Sunday. I also got down to the machine shop to pick up all the parts. What I'm planning is a slight warm up to the stock engine while ditching some weight. The basics are:

*Stock block, stock forged pistons and rods (the block had a tiny bit of taper and ridge that needed a bit of honing, stock pistons still within specs to use)

*Flo-Tek aluminum heads, 203505s, 180cc runners, 1.94 intake, 1.54 exhaust, stud mount rockers. These were given to my head man for a once over and for the price they are reasonable pieces. I port matched them to the Fel Pro gasket.

*Comp Cams CCA-35-514-8, 216I/224E, .544"I/.555"E, big improvement over the 210/210 stock at around 0.448" lift.

*Crane 1.6 roller rockers

*Edelbrock Air Gap intake, port matched to Fel Pro gasket

*Holley Sniper EFI

We're shooting for around 260-300 rear wheel hp from the combo and I think that will get us there. We've got to do some volume work on the heads and piston relief to figure out what gasket we want for an approximately 10:1 compression ratio. Also need to clay it up to make sure it'll work correctly. But all that stuff, setting the rocker wipe pattern, etc. comes with the assembly.

Work continues on the Mustang. We use any chuck of time, from 20 minutes to a couple of hours, to continue making progress. It all adds up. So over the course of a day we were able to get the block painted up and the crankshaft in and torqued up.

We had a couple of mismatched Ford Blues so we corrected that to a uniform dark version.


All the parts laid out for the build. Hopefully we'll turn this into an assembled engine by weeks end.


Setting those bearings in place.


After a lesson in clearances and scratching her head how to use a tool to measure 0.001" I introduced her to plastigauge. She was impressed and it matches her nails.


Torque those mains! Welcome to the Earp Garage and Gym. She's learning something about torque.


Ron Earp

Work progressed quite a bit over the last day or so. Mucho progress. We got the crank in last night and after school today we continued with the rotating bits. Sydney learning how pistons go in the bores.


Setting bearings in the rods.


Learning how to use her grandfather's ring compressor to put those pistons in the block. And yeah, that ring compressor sucks but it still works. Just have to be a bit careful with it. And hit harder.


Rotating the crank around for better rod to journal position. Took a bit of learning to understand that part.


Torquing those rod bolts. Doesn't take much and we learned that one of our wrenches if off quite a bit on actual value.




And meanwhile on the other bench some nasty work of cleaning up the stock arms for good bushings and weight jackers continued, with some beer fuel and help with Jeff G.



And, across Cary, work by Fred is happening with the body.




Things are happening. I still don't know if we can hit that August running date but we are damn sure going to put in the effort. And I think Sydney is on board with that too. Next up, heads on, oil pan, and front dress.

Ron Earp

More things are happening. I know it is seeming like the motor build is taking a long time, and it is, but lots of learning is happening along the way. I think we'll be done with it this weekend. We still have to clay up the piston to valve clearance and measure the valve reliefs for an accurate compression ratio check. That involves a bit of arithmetic and ingenuity on how to determine the relief sizes. I'll see what she can come up with there. But in the meantime the engine cam was degreed and installed.




We're making the rings that support the threaded perch at the correct angle. These will be welded to the arms in another segment.


And over at the body shop the repairs are all done. Fred had to work one some floor repair, hood repair, and put on a new trunk lid and fender. It's all on, squared up, and primered ready for sanding.



Ron Earp

Stoked, paint is happening! I know there is still much to do before it'll be done but I am looking forward to getting the car back in the garage and getting on with the build. we've been busy with subassemblies but the engine, tranny, and rear are all ready to drop right in and allow me to clean up the garage.



Ron Earp

Sydney has been tied up with AP exams but work has continued on the front suspension. We're building the front arms just like hte SCCA cars we've done so they will have adjustable perches for corner weighting, ride height adjustment, and they'll use the springs we have lying around thus putting those to good use.

Step one, make yourself a pair of shims by cutting a 22 degree section from a piece of properly sized pipe.


Buy yourself two weight jack plates with 1"-8 thread, cut them down to about 3" width, and weld each one to the shim making this:


Get your front crossmember and arms out on a table so you can mock up the alignment. Hand the arm, put at the point where they will be for proper ride height, and sit the piece you made on the arm. Clock the piece so that it points to the upper spring perch. Using the weight jack bolt will help. Onc clocked weld it in place.




Then go make the arms pretty with some chassis paint.



And this is the end result. Two arms with weight jackers and spring cups. Why put these in this car? I dunno, cause we can I suppose. Eventually I think the car will end up being my toy and it'll go to a track day or two and AutoX, so, it might as well be setup to handle well. However I plan to use isolaters on the springs here where as we do not on the race cars. Cut back on some chassis noise.



Meanwhile the engine assembly is progressing and Syd and I have clayed up some parts for compression ratio calculations. Without taking into account the area from the top of the piston to the first ring we're coming up with around 10.6:1, so that'll drop a little bit in reality. Next up will be getting the pushrod length straightened out and looking at the wipe patterns on the valve tips.


And I stopped by the paint shop yesterday to get some better pictures of the car in color. I think it's looking sharp. Color looked much better out of the booth than in.