Vorshlag Blog

What on earth has he brought to the shop now? This 1966 Honda S600 coupe is one of Honda’s first sports cars, heck one of the motorcycle company’s first ever production cars. And we have one, and we’re going to do something cool and crazy with it – which you can read all about here.

This unusually smol car came from the factory with a super high revving (9500 rpm!) motorcycle based engine, but that is long gone in our car. So we’re going to do what many folks have done with this chassis – swap in a modern 1000-1200 cc sport bike engine! The 1200 cc inline 4 in the S600 roadster above gives you a glimpse at how small the engine bay is, and what we have to work with. We discuss two possible Honda motorcycle engines to use – including one with a DCT transmission! – in the forum build thread’s first post.

We also talk about the possible suspension upgrades we have in store, as our coupe is sitting on a temporary frame and Miata front and rear subframes, which we will likely incorporate in our final design but in a much narrower format. We’ve got some rust removal in store using a “LASER” later this week, and we will show more of this ugly duckling soon – and hopefully it becomes a beautiful swan when we’re done! You can read more starting here.

At the end of 2024 we had our barn find 1995 BMW M3 – which we dubbed Project #Hellrotten – running once again with the original BMW S50 3.0L inline six. The Vorshlag crew had done a good bit of restoration to get it to this point, and a set of Motion Control Suspension “RR2” coilovers with Vorshlag top mounts had improved handling dramatically at the first Track Test. This is where the latest 6-part Forum Build Thread starts…

It was late December 2024 and we had a little more than 3 months until the first SCCA Time Trial event in Texas for the 2025 season. So during an already busy time at the shop we managed to transform the M3 from an E36 with a stock drivetrain and bodywork into a widebody, big tired, Link ECU EFI, custom exhaust, and very lightened race car. We started off with some ABS repair work after we had a fault at the previous track test.

Externally we made some big changes, including a fiberglass Fitment Labs Phase 3 widebody overfender kit. This was installed and track tested with 18×11″ wheels and 315mm A052 tires all around, and we finally had a “drama free” track test #2, followed immediately by a baseline dyno test with the stock drivetrain – all covered in the forum update. Back at the shop after that test, a custom splitter was built and installed with double canards up front, and a Nine Lives Racing 71″ wide wing out back. The overfenders and sunroof delete panel were refinished in the OEM Hellrot red color.

Then a custom exhaust was built using stainless long tube headers and a proven dual 2.25″ into single 3″ mandrel bent stainless exhaust – that both dropped 57 pounds and picked up 30 whp at the peak. We were able to tame this with a Plug-in Link ECU system that we show the installation of in this update. With some clarification on rules we were able to knock another 123 pounds out of the interior and still be SCCA “Level 2 Safety” legal. We also refinished the headliner, rear deck panel, and the A- and B-pillar coverings in microsuede, and it looks really nice. An RTD shifter went inside, too. We had all of this work ready and tuned just before the March 29th event we were aiming for. It was a major thrash for those 3 months, and we chronicled every step – every image inside the forum thread can be clicked for higher resolution images or videos. Thanks for reading!

We have been busy on the little 1988 Mustang LX notchback this summer and we’re close to firing it up with 3x the engine displacement and heading back to MotorSport Ranch for more test laps before we dive into the suspension development work we have in store.

In the latest Forum Build Thread update for our 21st Century Fox project we cover the dismal June track test we did with the original 2.3L four cylinder, which lasted four laps before the engine began sputtering and shutting off. Max speeds of 74 mph, slowest lap time we ever recorded – just awful. Shortly after getting the Fox back to the shop we found the cause, and dove into an engine swap using an “all aluminum V8” and a Tremec TKX manual transmission – with the goal of a “quick upgrade” to get back to the track for a proper baseline test with the stock suspension. Best laid plans…

Things quickly snowballed and this turned into a full on 500 hp upgrade, which is the opposite of what we advise our customers to do (chasing power is last!), but we have our reasons – explained in the Forum update. The V8 swap went pretty far afield, with an 8.8″ limited slip axle upgrade, complete fuel system, new cooling system, hydraulic clutch conversion, and much more.

It happens – just a simple plan that snowballs, as one upgrade leads to needs in other areas. We cover a lot of these systems, the decisions and actual work, in the latest update. Even if you have no interest in this chassis or even this engine, many of these techniques we show in detail could apply to your project. Who knows?

One of the wildest revelations from this “quick upgrade” to the drivetrain was how heavy the 1980’s iron four cylinder and T5 manual were compared to the modern aluminum pushrod V8 – the latter was actually lighter, which we did not expect. Lots of weights are given and great detail in the thread.

We covered about three months in this 4-part forum update, which is chock full of pictures and video. Lots more to cover next time, as we’re ahead of where we left off already – but have so many other build threads to update. Thanks for reading!

The latest 5-part entry into the massive S550/S650 Development forum thread covers work we did on our 2015 Mustang Time Attack Car we call #Trigger in the first third of 2024. Yes we know, we’re behind, but these entries are massive undertakings with hundreds of images and videos, and tens of thousands of words. You can catch up with what we have written starting here.

We cover in detail the addition of a roll cage, carbon widebody fenders, and massive 18×13.5″ wheels and 345mm Hoosiers to the existing setup, which included 315mm A052 “200TW” tires on 18×12″ wheels. There was also a Haltech based adjustable traction control system that Billy at Rapscallion Motorsports added and helped dial in.

Ever wondered what it took to add massive tires? The flare addition is the easy part – the REAL work is underneath the flares! We show this step-by-step in exhaustive detail starting in the latest forum build thread entry.

In the first 4 months of 2024 with this car we fought with front end lift, added vents in numerous places, had faulty clutches, wore out some synchros, cheap coils, a bad starter, chased an ABS fault, tires rubbed, and we did a bunch of track tests and competitions. It wasn’t all bad, as there were some wins, and more wins followed later in 2024 – which we will cover next time. Again, you can read the latest entries here – thanks for reading!

We have been cooking up plans to tackle some major suspension changes to the Fox and SN95 generation Mustangs for some time. We started gathering parts for the 21st Century Fox project in 2016, then we got busy with many other things and we paused this work for a mere eight years…

In 2024 we got back to this project using this development mule, a 1988 Fox Mustang LX with a lowly 2.3L four cylinder. This is Terry’s 8th Mustang, and it is an ’88, so we call this car #TheOcho – He is not right in the head, with his irrational love of Fox Mustangs, especially the notch back versions!

This Fox is part of a Concept of a Plan we began a few years earlier, and we have been gathering cars from the 1980s and 1990s to tackle some 21st Century suspension and design updates. All four of the cars shown above have been utilized to create new Vorshlag products, and we’re just getting started on the Fox Mustang. We even list the other build threads for the E30, E36 and 3rd Gen inside the new SN95/Fox build thread. And yes, we’ve already done some product development work on a 1995 Mustang, from the SN95 generation.

This forum thread covers what we have planned and what we have completed so far on the Fox and SN95 Mustangs. We will continue to update the Fox/SN95 Forum Build Thread, our YouTube build diary entries, and post about the work on our socials as we progress. Thanks for reading!

At long last, after a Summer and Fall of maintenance and repairs, our little BMW E30 was ready for the track. This car is a 1991 BMW 318is that we used for development and autocross competition from 2007-09, then it went away and changed hands many times. But in 2024 we had the chance to buy it back, and we did!

After restoring the car enough to get it street worthy, we had one task left – replace the 13 year old tires that were cracked and aged out. We went a little overboard with these fat 225mm Bridgestone RE-71R tires, but wow – the GRIP! These 200 Treadwear tires have come a long way since 2007. And we had to do some things to “make them fit”…

We hadn’t driven this E30 on track since 2008 and it was JUST AS MUCH FUN tracking it in 2025 as it was then. Likely more fun, as the grip levels were much higher with modern rubber. The old AST dampers held together for this track test and of the two drivers that day, Amy Fair came out on top. In the latest Forum Build Thread entry we cover all of the upgrades, tweaks, test drives, and track videos.

In this latest update we discuss an engine upgrade – to something newer and more powerful, yet hopefully not too heavy or “overdone”. We only show the LS1 V8 above to show how small the J-series Honda SOHC V6 really is (we will absolutely not LS swap this car). A lot of measurements, testing, and research sadly led us away from this potent and lightweight V6, but we do have something more interesting and spicy in mind.

Link: https://www.vorshlag.com/forums/forum/vorshlag-motorsports-discussions/vorshlag-project-cars/59265-vorshlag-bmw-e30-development-thread-1991-bmw-318is?p=59282#post59282

Clink the link above to see what we’re up to. Thanks for reading!

When we dropped the Bilstein brand (due to a completely loss of faith in their stocking ability) in 2025, after carrying it for dozens of years, we already had a replacement German monotube brand in mind to fill that entry level coilover gap – H&R!

H&R carries a catalog FULL of very robust, inverted monotube strut coilovers and shocks. We began exploring this brand in early 2025 with the S197 Mustang offering, then after digitally rating the included springs and offering these assembled with Vorshlag top mounts (for our “StreetPro” replacement, above) – we immediately began to add our own twist on these with replacement springs that have a stiffer spring rate.

This “TrackPro” offering replaced the missing suspension option for this S197 chassis that we used to fill with a Bilstein B6 monotube that we modified heavily to turn it into a coilover. Over $1600 less than the least costly monotube coilover we carry for this S197 model, the H&R fill a niche for some of our customers.

After selling the first few sets of H&R for the S197 chassis, we dove into the next car model: the S550 Mustang. We have already made the StreetPro and TrackPro versions of these, and will keep expanding our coverage with H&R into other car makes and models.

And while these are just ride height adjustable, with no damping adjustment, for some folks that is a good thing. We also sell each setup with only one spring package, not a choice like with other brands we carry. No knobs to turn and no spring rates to choose = less chance of tuning yourself into a corner! Call us at Vorshlag if you have questions about these entries or other car models.

In this 3rd chapter to our huge Forum Build Thread and series of GRM magazine articles we cover some major prep work to the Pontini Racing 2014 BRZ. This time they have a roll cage built, and we dive deep into the choices for doing this critical and required safety step.

After the method of having the cage built was decided, the shop picked, and the deed completed the team jumped into prepping the floors and cage to be painted. We cover 3 methods to paint the cage and 2 methods to remove tar paper off the floors. Then the window net was installed, then the fire system mounted and plumbed.

The team also installed a motorsports style defroster, tow hooks at both ends (including a custom soft rear strap), Lexan rear window, multiple CNC cut and hand made aluminum panels for various controls and switches, and all manner of other details. Then the car was weighed and off to the track the team went for Track Test #3 – one week before their debut ChampCar Endurance race! Hundreds of pictures, tech tips, in-car videos, and more are covered in Part 3 of the Forum Build Thread. Thanks for reading!

This might be a blast from the past for you long time Vorshlag fans – we purchased this 1991 BMW 318is back in August of 2024 that we sold in early 2009. Purchased originally in 2007, this was one of the first four cars we built up when we started Vorshlag. We had a Forum Build Thread for this car that we started in 2007 but decided to kick off a new E30 Development Thread for this new chapter.

This one had been sitting for several years in the hot Texas sun, which baked off the paint and damaged some things like the dash. But we couldn’t just let this car rot away and the sellers were happy we could buy this back and restore it to its former glory.

While restoring this car we are also using it to develop some new products for the BMW E30 chassis, like these brake cooling deflectors (above), new seat brackets, and much more to come. We have even picked a Time Trial race class to build towards, with an eye towards competition later in 2025.

After replacing brake rotors, pads, hubs, and other fluids we got to work on the interior. Now this E30 has a new dash pad, Sparco tilt back seats, Sparco harnesses, a MOMO steering wheel and NRG quick release. The paint needs some serious attention but we will attack that, all in good time.

We have chronicled ALL of this work from August of 2024 to February of 202 in this new Forum Build Thread. The forum coverage stops right before we got these 225mm Bridgestone RE-71RS tires mounted, earlier this week. We have done several test drives and the car is loaded up to go to MSR Cresson for some baseline lap testing later today. Thanks for reading!

As of January of 2025, we have discontinued all of our Bilstein based website entries. This was not a choice we made lightly, as we have been a Bilstein dealer for over 15 years and have developed numerous unique products using their dampers. The availability of the Bilstein dampers has been extremely limited, and once they run out of stock we have to wait months (sometimes 6 months or more) before product is available again.

As a small company, we at Vorshlag can only afford to hold a limited amount of stock of Other People’s Parts (OPP), and we rely on being able to restock frequently direct from the manufacturer or a wholesale warehouse. The way Bilstein is functioning the last 8+ years we would have to buy a full years’ worth of stock for every part number we need from them – then hope that we can sell it, or that we don’t run out.

With so many Bilstein based kits we listed on our site, we constantly ran into long lead times for items that our customers ordered. With the “Amazon-ification” of online shopping habits, customers have nearly zero tolerance for waiting. Those delayed orders inevitably turned into cancellations and refunds, which costs us both time and money – and it hurts our reputation with those customers.

We were happy with the quality and function of the Bilstein monotube OEM replacement dampers and PSS coilover kits, but we simply rely on their inventory. To complicate things, Bilstein has an extremely low profit margin for their authorized dealers (due to a very big gap between their set MSRP and allowed MAP pricing). That is almost acceptable if we can order products as needed (and add something to them like our top mounts, to make some sort of profit), but that slim margin does not cover the holding costs to have a full years’ worth of stock sitting on our shelves.

We recognize this creates a hole in our suspension offerings for our lower cost of entry “StreetPro” kits (see above), the PSS ride height adjustable coilovers, and even the modified coilovers we made from their monotube B6 dampers we called the “TrackPro” (see below) – which we built when Bilstein didn’t make a PSS kit for a particular car model.

We have identified a potential replacement supplier of quality, monotube dampers with ride height adjustability and a huge model range. We will be testing this more attractive option soon, but we also need to verify inventory of this brand before we add them to our website. Stay tuned!