Vorshlag Build Thread - 67 Mustang Pro Touring/Track Car

[cabudge09]

Originally Posted by slimjim

So I see you went the way of the AJE k-frame. did you also use their control arms and suspension or still plan on something a little better?

Just their K member. Terry is looking at spindles and will fab the control arms in house once we decide on a spindle. We will significantly improve the suspension geometry over stock while also giving ourselves a little more room for wider tires up front. The plan is to also add wheel speed sensors for ABS and we are converting to EPAS. Terry sold me on the idea of EPAS as we both have seen fires due to power steering fluid getting on headers. No more power steering pump overheating and spitting fluid in the engine bay on track days.

Adam

[slimjim]

Originally Posted by cabudge09

Just their K member. Terry is looking at spindles and will fab the control arms in house once we decide on a spindle. We will significantly improve the suspension geometry over stock while also giving ourselves a little more room for wider tires up front. The plan is to also add wheel speed sensors for ABS and we are converting to EPAS. Terry sold me on the idea of EPAS as we both have seen fires due to power steering fluid getting on headers. No more power steering pump overheating and spitting fluid in the engine bay on track days.

Adam

Very neat, I look forward to seeing what sort of setup you choose, I like the AJE K-frame as they're the only company who allow drop in fitment of an ecoboost engine

[ur-n-8]

You don’t seem too fond of the wilwood brakes, what would be a quality brake?

[cabudge09]

Originally Posted by ur-n-8

You don’t seem too fond of the wilwood brakes, what would be a quality brake?

We are going to run with the S197 14” brembo brakes and spindles.

[Fair]

Project Update for May 28th, 2020: A lot has happened with this project since we began work last November. We have the AJE tubular front crossmember installed, 18x11" wheels are on hand that fit under the stock bodywork, a 427" LS7 dry sump crate engine has been installed with a manual transmission, the Radium Engineering fuel cell is installed, and we have started work on the roll cage.

​​

We have also removed the old front suspension & brakes and sold it, removed the old 302/T5 drivetrain and sold it, installed composite doors, fixed the floors, designed and built new front suspension, and installed modern Brembo brakes / hubs / spindles from an S197 Mustang.

​​


We did much of this work this Spring while we were semi-shut down, with our crew working about half their hours to create a bit of social distancing, and already spread pretty thin on a number of ongoing projects. But we have great progress, and you can see that in the update below.

PICK FRONT CROSSMEMBER + SUSPENSION DESIGN

I talked about front suspension options last time, after we looked at a lot of "modern" replacement front crossmembers / suspensions / brakes, and felt that for this build we needed something... a little different. While it would have been fun to spend $20-30K on some of the really fancy Corvette based front "suspension in a box" kits, they just didn't fit this car's budget or needs. This is to be a track car, not a show car. There are no "Design and Engineering" judges to impress - just looking for lower lap times, more reliability, and and superior driveability.

​​

Our engineering group here at Vorshlag looked at all of the options and we picked the AJE tubular front crossmember made for the 1st gen Mustang. We talked to the folks at AJE and they agreed to send us one of this units but not powder coated, in case we need to move suspension pickup points and/or weld something onto their fabricated piece here. It arrived in a few weeks and the construction and welds looked great.

​

This is normally paired with their SN95 Mustang spindles, their control arms, some drag type struts and top mounts, and SN95 Mustang brakes. Of course we aren't building a drag car here, and had another spindle in mind to use with a modified strut design - the 2005-14 Mustang S197 spindle. This offers more modern brake options, better hubs, and more advanced geometry.

​​

This tubular design seems a bit lightweight compared to the OEM crossmembers we have worked with in the past on S197 and S550 Mustangs. We might add a little more steel to this AJE assembly, as we plan to put lateral grip from 315mm tires through this thing. But remember - the '67 came in here with NO lower crossmember up front, so this is already much stronger than what it had. Time to get this installed.

WAIT... FRONT STRUTS?

Yes, we are converting this car to have a modern version of a McPherson Strut front suspension. This will replace a front suspension system designed in the early 1960s that packages very poorly and has pretty poor geometry. I am sure some of you are rolling your eyes, but remember - strut cars don't necessarily suck. We have sold thousands of high end strut and shock setups for a variety of cars that have won thousands upon thousands of races.

​​

If you think we are going to make this car somehow slower with this "lowly strut suspension", you haven't been paying attention to race results. This '67 will will have the same struts / brakes / ABS / spindles as our 2011 GT above, which did pretty well in NASA, Optima, and other competition arenas - along with hundreds of other track focused S197s we have built or supplied. The '67 will also have 315mm tires, but be one thousand pounds lighter than our 2011 GT, and it will have more power.

REMOVE EXISTING DRIVETRAIN

This work started November 14th, 2019. The car "drove" into the shop with a running, carbed "late model" 5.0L HO engine from a 1985-93 Mustang. It had a T5 Z-spec 5 speed behind it with a hydraulic master/TOB conversion driving the Ford 9" built by Currie. The exhaust was off when it got here, however, and it was having some tuning issues, so I didn't get to drive before we tore it down - but the owner had done a number of track events with this built engine and T5 trans before.

​​

The brake balance was so poor on track (made up of all Wilwood bits) that it turn the tires into "squares" every time he tried to use the brakes hard on track (he tracked a late model GT350 before this car). Ideally I would have liked to have driven the car beforehand, maybe put in some baseline laps at MSR or put it on a chassis dyno for a baseline power number. After building / owning / tuning / driving a number of engines and cars from the Fox Mustang era, and looking at the parts list, I suspect it made around 275-325 whp. That range seems low by today's standards, but that's a somewhat lofty number for a '85-93 5.0L with a cam and heads. A T5 won't live long with much more than that, as many people know, so the upper 325 whp number is probably opimistic.

​​

Brad and Evan removed everything ahead of the rear axle in the drivetrain. Fluids were drained, we scarified a chicken to the Ford Gods, and began the "travesty" of yet another LS swap. Driveshaft out, then it was time to dig into the MSD, distributor, and all of the rest that would never go back into this car.

​​

Care was taken to not damage any paint, existing chassis wiring, or any of the parts we were removing. Our customer is not on the Book of Face so we were taking pictures of the drivetrain to help him sell it - to help fund the work here.

​​

The owner was chasing some exhaust leak issues, but Brad found the leak, at the header. The composite cowl hood was removed before we began and will not be going back onto this car, as the extra height is not needed with an LS engine. A flat composite hood will do just fine.

continued below

[Fair]

continued from above

​​

After a little work we had the drivetrain out and intact, ready to live life in another Ford car some day. Engine bay looked pretty cleared out at this point, but we needed to keep going.

​​

One of the more industrious Mustang parts hustlers in Texas - who had bought a nasty Fox Mustang chassis from me before - came and got all of this drivetrain as well as all of the suspension / brake / bodywork shown below.

REMOVE SUSPENSION, PREP FOR STRUT CONVERSION

During the same week as the drivetrain work above happened the aftermarket front suspension and brake parts came off this car for the last time.

​​

The "double A-arm" front suspension in the 1st gen Mustangs has an unusual layout. First, the spring sits ABOVE the upper control arm, which gobbles up a LOT of inboard wheel room up front. Then there are the two lower control arms, which includes the "Tension Control" rod. It really is a hot mess, but hey, it was designed almost 60 years ago. All of that came off, including the "spring pocket" above the control arm. We aren't going back with anything like this.

​​

The main lateral control arm's lower mount is a wrap-around structure that forms the inner shock towers as well as the lower structure, shown above right. These were original welded bits held in place with dozens of tack welds. Ford didn't really do corrosion protection all that well back in the 1960s, but this car spent most of its life in Texas so the raw metal underneath was mostly just dusted with surface rust.

​​

Evan fought this battle for a couple of days: finding and marking spot welds, center punching them, then drilling them out. The spot weld cutter gave way to a unibit for most of this work. The inner shock tower structure that tack welds on was removed but the "strut tower" structure was left in place. If we needed the room for the LS swap we could take out some of this to make room (we didn't need to).

​

At this point we mocked up the AJE crossmember with some clamps. There was some fore-aft adjustment we could use on the crossmember if we needed to alter the engine placement or control arm pickup points. But those front "TC" rod mounts had to go next.

​​

Even used more spot weld drilling and a little prybar work to get those brackets out of the way. The lower radiator support was still in good shape, too.

​​

There was some inner shock tower "rings" that were removed (on box above right) but I missed that step. We had more work planned for the strut towers later. The welded structures were all kept to show the customer, then made their way to the scrap metal bin.

​

Jason, Myles and I looked at the placement of the crossmember and figured the LS engine would "tell us" if we needed to move this forward, to clear oil pans or alter the control arm placement. For now we left it where AJE intended.

​​

Since the old front suspension was now "gone for good" our crew made some "skates" that bolted to the front frame rails. These help us roll the car around the shop between stations and tasks. We do not have an unlimited number of work bays so we juggle cars around between fab areas, 2 and 4 post lifts, and "storage" areas.

​​

To help expedite the sale of the old suspension (and to make room in our shop) I posted the control arms, steering rack, spindles, brakes, engine and trans in January of 2020.

​​

The same guy bought all of it plus the steel front fenders and the cowl hood, which was a nice haul of parts for him. I wasn't a huge fan of the cowl hood and the owner agreed - we will stick with a simple OEM style hood (but likely composite). The sale of all of these parts funded the build for several months, too.

ROLL CAGE, GUTTED INTERIOR, & COMPOSITE DOORS

This '67 came into our shop with a 4-point roll bar welded in place, but built around the stock interior. We were looking at possibly just repairing some of the design aspects that we felt were incorrect or less safe than they could be.

​

For a dual purpose street/track car, a properly designed 4-point roll bar (or "half cage") is a great alternative for track use. It gives you some rollover protection plus a solid place to to hang shoulder harnesses from, all without putting steel tubes next to your head, arms and legs - which can do more damage than good when street driving without a helmet / 6-point harness. But this one had some issues...


continued below

[Fair]

continued from above

​

The main hoop was too far forward, pushing into the seats. The horizontal harness bar was mounted too low, which is pretty obvious when you saw the seats / harnesses it came in with. This can lead to a compressed spine when the shoulder belts are pulled tight in a forward crash. The rear "downbars" are also more of a drag race style that land way back in the trunk, near the rear bumper.

​​

The owner of this Mustang (Adam) came by in late November for a seat "fitting", and we talked about modifying his 4-point roll bar to make it safer. We looked at his existing Corbeau seats (above left) which were sitting WAY too high. Then mock up a lower mounted seat using a Sparco (above right), which gained him a lot of headroom. We also showed him where an upper door bar tube would run if we built a cage ahead of the 4-point.

​​

I was more than OK letting this car leave here with the 4-point, if we cut out out, relocated the main hoop, raised the harness bar, added a diagonal in the main hoop, and made changes to the rear down tubes. We have done a LOT of these in dual purpose street/track cars, and I stand behind those setups as the better compromise for a car that is street driven. But in the month since we started the build on this '67, Adam got the bug to go further with the safety upgrades, and the scope creep began...

​​

We saved him a chunk of money by not going with an expensive "front clip in a box" that he felt it could be better spent on more serious safety upgrades. Full fire system, full cage, gutted doors (that then morphed into composite doors), and a stripped interior. This was all Adam, but since he waited quite a long time to get his car in here, it was hard to say "No" to more safety.

​​

Brad removed the seats, headliner and carpets - the flammable bits that make a street car more livable but a race car more dangerous. This car had some work done previously and the front "tar paper" insulating materials seemed new. The rears were not. Brad used heat and gentle scraping to remove the tar paper, which is no longer needed when you have the carpets removed. Read more about removing this vile stuff here.

​​

Brad removed the same stuff from the trunk and back seat areas along with the floor mats, visors, some speakers and some other bits.

​​

All told we removed 43.3 pounds of carpet and insulation, not counting the seats (which would go back in - or something similar to these). That might offset a chunk of the weight we will add by changing from the 4-point bar to a full 6-point roll cage.

​​

At this point the interior was stripped, and we had cut out the 4-point roll bar. I will show more of the cage construction in a future post. Before that work began, we had to deal with the floors.


continued below