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C1 Motorsports Evo Swap Time Attack Eclipse


Supporting Member
Jan 6, 2007
Central Valley, California
In preparation for the sequential's arrival, I finally spent some time cleaning up the engine bay. While it was funny showing billet parts in an engine bay worthy of a "cash-for-clunkers" 90s tv commercial, it is time to get ready to install some engine and transmission parts.

Before and After ENgine Bay.png

We're a long way from perfect, but the front radiator support will all be cut out soon and there is a good chance the car will likely get soda blasted before paint. The rags used to wipe the car down were soaked red with paint that was easily rubbing off, so it's going to need to be addressed before the final assembly. Before worrying about that though, let's get through the initial assembly :)

Cleaning a car is not exciting, we've all seen that (and to better effect) so what can I share that IS exciting?

We've acquired our Motec electronics package and mil-spec wiring loom ready to go from Powertune in Australia!


The Motec M150 has the GPRP firmware package, which enables paddle shift control of the sequential and flat foot up and down throttle and ignition cut control. This is what will enable the 20-40ms shifts of the sequential to be possible, without intervention or driver modulation of the throttle position for shifting either way. Since this is an integrated feature of the ECU, there will not be a need for an external gearbox control unit, keeping things tidy while enabling even quicker closed loop shift operation with nothing more than the gear position sensor embedded within the sequential's shift barrel.

The solutions this ECU provides in conjunction with the sequential transmission is every reason this project is even taking place, so we are VERY excited to have this in hand.


In addition to the very advanced ECU, we also procured the top of the line C187 Motec Dash. This is a 7 inch datalogger that captures data at an incredible 1 kilohertz! Compared to the 20-25 hertz of DSMlink, that 1000 samples per second is critical for suspension analysis, and you can do really neat stuff with oil pressure logging at that kind of rate. You can see every hit off the gear pump, then you can look at frequency analysis to see if the belt is slipping and you can see if gears are dying, etc. Stuff that was unimaginable before is stuff race engineers are doing on a regular basis.

I am new to all the features this thing is capable of, but talking to Andrew, who deals with these massive data loads for a living, is bringing me up to speed. The cars we all admire at the top of Time Attack really are running on the ragged edge, and that is only possible with data. Data is King!


What you are looking at here is the Motec Power Distribution Module, which acts in a way not too dissimilar to the fusebox you might find in your DSM, in that it distributes power throughout the car. Except it's very dissimilar in that this box is all your fuses, relays, breakers, and has programmable logic for every single power out. Logging is available for the voltage and current of every output, and fuses are programmable in 1 amp increments. Say you set your radiator fan to 18 amps, and it hits 19? The PDM logs this event, and assuming you program this behavior, resets the breaker, return power to the fan attempting to get it going again. It can do this 100 times a second. I remember a day and time I was trying to track down a parasitic draw on the GSX's battery over night. With a PDM, I could have seen every single circuit and known exactly what was causing it and how much current it was drawing. Electrical shorts are a thing of the past. You could see the exact second a wire sheathing started rubbing off and exposing bare wire against the chassis. You could have the PDM keep the car going the rest of your lap by pulsing power output if it was a non critical interruption, or using the dash alert the driver and limp the car back to the pits. It's truly next level stuff.


This box is actually more simple then the rest, as it is an expansion unit that allows more inputs and outputs to expand on the ECU's internal. This unit currently is just connecting the EGT sensors of the car, and transmits this data back to the ECU and logger via CAN.


This is an actually surprisingly advanced piece of hardware. This programmable keypad has 3 LED outputs for each button along with back lighting for the entire unit. The buttons can also be used either as a toggle or momentary switch, which is handy for differentiating say a push button starter motor vs a toggle switching your fuel pumps on. Best of all? Only has 4 wires: Power/Ground/CAN High/CAN Low. Compared to the old dash, which has 2/3 wires per switch. You can imagine how much cleaner the wire will be in addition (or should I say subtraction) to the weight savings in wire.


old dash.jpg



There will be some wiring left for some misc stuff like brake lights and things like fuel injectors and engine loom, but with autosport connectors for ease of installation and removal pre-wired, the final loom should be pretty sweet for years to come.

Hopefully this was informative for those who don't know the Motec product line, as it has been a blast learning about it myself. Can't wait to get this all in the car soon!
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Supporting Member
Jan 6, 2007
Central Valley, California
It's here it's here it's here!!


The whole reason for the chassis swap was for this transmission, so having it here is a big step in the completion of this swap.

We have acquired a 6 speed sequential transmission from our sponsor X Shift Gearboxes. We have decided to go with a close ratio 6 speed with a final drive all picked gear by gear to match the needs of Eastern Creek in particular for World Time Attack Challenge, though it will suffice for domestic events as well with Global Time Attack and Super Lap Battle. X Shift also builds higher torque rated 5 speeds with longer ratios for drag racers. They work with each buyer individually and build a box perfect for their needs taking into account tire sizes and application.

The next steps for the build requires assembly of the transmission clutch housing and final drive, but I didn't want to wait for that to all wrap up before sharing photos of the open transmission while we have the opportunity to see the dog engage straight cut gears.


Super exciting!!
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Supporting Member
Jan 6, 2007
Central Valley, California
I have mentioned paddle shifting sequential a few times and talked specifics on where we were getting the transmission, but haven't talked much about what would be actuating the gearbox. Let me introduce you guys to the MME Motorsport paddle shift kit.


This kit is available in different levels depending on your ECU and throttle body solutions. Since we have a Motec M150 ECU with the GPRP (paddle shift) firmware AND we will have a DBW solution for the throttle body, the ECU can fully control the closed loop system, giving it the ability to actuate the shift barrel, blip the throttle, and cut ignition for lightening quick 20-40 MS shifts. No Automatic or Manual DSM transmission can match that.

Let me explain why I keep quoting 20-40MS range. There is a variance in every shift, that can vary between that range (or more) for each gear. There are two main control system options to complete that shift.

An Open Loop Paddle shift system is hard coded. In psuedo code: a tuner will say close throttle for 30ms, actuate the air relay to shift transmission for, then open throttle again. They go on the dyno, test this for a few hours, adding and subtracting time til it shifts "perfectly" and do that for each gear, trying to take into account as well RPM and such. It works, kinda. Let me explain how this would work. (The tuner would NOT know the exact duration of a shift without a feedback gear position sensor, but for the sake of discussion, we will) Let's say we are tuning the car, and shift. The actuator is supplied with air and begins to move, and the gear selector (barrel) rotates and shifts and this all takes 22MS. "Awesome" you might think, and set the time to keep the throttle closed or ignition cut to 22MS. Let's say you try it again though, but this time it took 31MS. If you were using the same settings as before, you would not have completed the shift, you would have rounded your dog gears a tad, and have a harsh clunk as you completely botch the shift. Tuner then has to set the time delay to 31MS. Realistically, this experiment would go on over and over, OR it would just be set to a conservative number to begin, say 40-50MS so you don't risk ruining the gears. Still, very fast, but if the gear switch takes place at 22MS, and the delay is set to 40-50MS, that is just wasted time. We are building a time attack race car, this is not good.

A Closed Loop system on the other hand, uses sensors and system feedback to calculate all this. The throttle might only need to be closed for 19MS on one particular shift, because the gear position sensor tells the ECU 'hey, I am done shifting now'. The ECU can then resume the driver's previous rate of throttle. Next shift the gear takes 30MS to switch, so the system delays everything for 30MS. The next shift is at 23MS, the delay is 23MS. I don't think it takes a rocket biology degree to understand that a Closed Loop system is far superior.

So because of the benefits of a Closed Loop system, we chose to go with the Closed Loop MME Paddle shift system, and if you consider moving to paddle shifts one day, you should too :)

If you don't have a Motec ECU, MME also sells an actuator and Gearbox Control Unit (GCU) that is external of the ECU, but still has this same control. If you don't have a DBW Throttle body, they also have an actuator and air line hook up for that as well, to blip your throttle body physically/manually in the same manner.

Very neat stuff. This kit included the carbon paddles, the magnetic aluminum milled switches for the paddles, steering wheel mount kit, a CNCed actuator mount specific to the Xshift gearbox, CNC milled shifting actuator, air pump, and air reservoir. They also include the lines, pressure sensor, relay, and fittings to make this install as painless as possible. Really happy with this kit. For more information, check out their website link to this kit:

Til it all gets hooked up, check it out on the work bench:

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Supporting Member
Jan 6, 2007
Central Valley, California
This has been a good week for deliveries to the C1 Garage.

Next to arrive was from friends at Hypertune. We have been working with them for a few months now on a special order for the intake manifold and other goodies to start to wrap up our intake needs for the build.

This intake manifold is modular, allowing us various options such as dual fuel rail and throttle body selection.

IMG_20200603_180307 (1).jpg



This was one of the hardest parts to pick for our build so far and felt the need to share a bit of that story. There are several options available for our platform, but every one we looked at targeted drag racing. They have large plenums and high flow ratings for big horse power, but every one of them lacked an attention to the mid range flow, which is critical for road course racing. The C1 team had a really big job researching flow maps of many popular manifolds for 4g63, including several billet options. The folks behind the best manifolds were great to deal with, and had the flow charts of their manifolds for us to review. On top of the CFM numbers, there are features of some that I really liked, but mid range flow is so vital to our car's performance, as you lose most of your momentum (and therefor time) in the corner of a race track. I have zero issues with the claims and benefits of many of the more popular manifolds for DSMs, but in the end we picked the manifold that best suited our application.

On top of all the independent research we did, Hypertune was present in the 3 time WTAC Pro class champion Tilton Evo. That sealed the deal for us. They too are well above the 1000 AWHP mark, so we knew we were making a good choice.



In addition to the intake manifold, we also picked up a Hypertune Front Mount Intercooler. We picked up their core core and end tanks to a size specced out for our car. Why not pick up a bolt in DSM kit might you ask? Hypertune makes billet end tanks!


IMG_20200603_180614 (1).jpg

The advantages here vs a sheet metal end tank are smoother walls and transitions, less restriction and less turbulent flow, all in the name of even less pressure drop, crisper part throttle response and more horse power! All these little things add up. They have a different tank design based on the inlet and outlet size selection. We're specially loving the Wiggins style clamps that will be used throughout the whole vehicle. There will be 0 (zero, ゼロ, cero, zéro) chance of boost leaks caused by a faulty T bolt clamp. No popping off, no risk. Yes, this is stupid expensive; I remember personally not so long ago I couldn't imagine spending 100s on EACH clamp when a 9 dollar clamp did the "same job". However, I've had clamps pop off at high boost, and that is simply not acceptable in a race car at the level I hope we achieve. This eliminates that even being a possibility.

What's more, is this is even better than a V-band clamp in that the o ring in the connection allows for flexibility in the pipe connection. Imagine for a moment: a rigid V band connection at the turbo, which is mounted rigidly to the moving vibrating motor. That pipe and motor are now like one, vibrating and moving with the motor. That pipe mounts to the FMIC, which is rigidly mounted to the front of the car. Something has to give, and in most vehicles, that is the rubber coupler at the FMIC inlet. That means the rubber is fatigued, the connection is weakened. The whole time, pressure inside is pressing out on the coupler with no backing support.

All of those issues are eliminated by not rigidly joining the pipes. The o ring on the end of this fitting fits inside a joining coupler, and can move a few mm in and out, allowing for imperfect pipe fittings and flexibility in the connection.

Silicon couplers and beaded pipes work, but this is just simply the better way to do it. Bit the bullet and ordered a set for the whole car.


The outlet on our turbo's compressor housing is 2.5", so we have one 2.5" coupler, then that will open up to 3" at the inlet of the FMIC, to a 3" outlet. The fitting at the UICP will stay 3" until it get to the throttle body which is 3.5". This is to help the part throttle response by not being over sized, though by calculations, should be about the minimum piping size to still support 1000 AWHP.

Speaking of throttle bodies, we ended up picking the largest DBW TB on the market that supported high boost applications, an 82mm Drive By Wire unit made by Bosch.


We've comes this far with the Wiggins style clamps, mise well continue all the way to the TB connection. Hypertune once again came up with a solution, offering an adapter specifically for this TB.


Hope everyone enjoys the break down on some of our part selections. If there is any feedback or suggestions though, we're all ears!
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Supporting Member
Jan 6, 2007
Central Valley, California
So cool. Very exited to see this come together. Are you going to be running SD with this and do you have a sensors package planned?

Good question!

Speed Density and Volumetric Efficiency tuning is the way to go. It's the least restrictive in the intake, and it's tune-able in multiple dimensions.

motec tuning.png

As far as sensors are concerned, it's quite a bit, and includes what we already had in the car, and more now! I have still yet to calculate exactly how many sensors our car will have/need to have since with Motec, you get not only the pleasure of buying the hardware, but having to pay extra to unlock it's features...


The logger/dash alone with all features unlocked is not cheap, so before something is unlocked you have to calculate what exactly you need. I suppose it is nice you can buy the hardware for cheaper than the 14,000 dollar price tag with all features unlocked, but it gets expensive real quick as you realize you want or need more features.

I am sharing this to bring attention to the 44 I/O Upgrade for $1,300 dollars.


If we end up needing more than 10 analog voltage and 4 temperature inputs, we'll have to purchase the upgrade on the logger. The advantages of logging everything in the dash is it is capable of 1000 hertz datalogs.


IMG_20200527_092240 (1).jpg

The E888 expander is a separate device that was also included with our electronics package, primarily for its thermocoupler inputs that the original Spyder did not have. However, the E888 expander logs things much MUCH slower. 200 hertz is still very respectable compared to many club level ECU/Loggers, but its 1/5 the speed of the Motec C187 Dash. If the sensor count we have in need of faster logging is greater than what the base C187 offers, we'll have to upgrade.

This might not be a budget build, but homie got a lot of things to buy and support the team with then just shelling out for software upgrades. I'd love to still invest in some things like tire pressure and tire temperature sensors that a few companies have started releasing recently. They are very neat, but depending on if they communicate over CAN or if they need independent inputs might dictate the rest of the system.


One last thing your question reminded me of:


In the Spyder, some of the sensors were remote mounted to reduce temperatures, and increase longevity of the sensors. In the new chassis, we are taking that a bit more serious.


This is a sensor block for 5 different remote pressure sensors. Each is labeled individually and have a single bulk fitting to make removing the main engine harness super simple. Here we have the following pressure sensors:

Crank Case
Manifold Absolute

If I am feel that I can stretch the budget, maybe I'll get 5 new sensors all of the same type/length :tease: but these are all otherwise the same 3 pin fitting making spare sensor budget much cheaper then having 5 different OEM sensors. Lets not forget too how much simpler this makes swapping those sensors. I am still a novice team manager, but after spending last year on a crash course in running a race team, anything you can do to help the team in the paddock between sessions is huge.

We are using a Motec LTC CAN wideband, 12 tooth timing, the OEM mivec 9 stuff and fuel injector plugs, and swapping over the Motec Suspension height sensors from the Spyder for tracking vehicle dynamics around the track. Adding a steering angle sensor and brake pressure as well so we'll have a bit more information on the driver inputs as well. Oh, and we'll be adding 2 more wheel speed sensors now we will be AWD for the traction control.

To be honest, I am sure there is more I am forgetting. I'll add as many more sensors as the team thinks we need, though Andrew really had already added more sensors than any other DSM I had ever heard of already. Now we are stepping into V8 Super Car / Formula level logging and tuning capabilities, I am sure there will be even more data to capture. Our old tuner only had a 2WD dyno and he didn't tune Motec, so I'll need to either upgrade myself from my DSMlink tuning days or find a new tuner. That could also mean new guy wants more stuff logged, we'll see.

Hopefully that was enough info to answer your question. :thumb:

IMG_20200526_190432_01 (1).jpg
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Supporting Member
Jan 6, 2007
Central Valley, California
tube front.png

I think with a fresh coat of paint and rearranging some of the mounts for accessories flipped to the other side, the front of the new chassis will be able to utilize the old Spyder front. Where this mounts to the frame, even with the difference in the frame rails between the two cars, it's symmetrical far enough forward down the frame rail when it straightens out again after the hump over the transmission. I was on the fence deciding which aero kit to install, but if I can just bolt on the original V1 until the new V3 kit is done, that saves a few months of work and gets us testing the mechanical stuff sooner.


Proven Member
Mar 2, 2008
Orange, Texas
Does xshift plan to keep producing a 2g sequential transmission? To my knowledge, I don't think anyone else makes anything like this. Incredible build!


Supporting Member
Jan 6, 2007
Central Valley, California
They make them for the Evo 4g only. There are ZERO new off the shelf options for sequential for a DSM 4g63, hence why all the headache with this swap. If there was an option, any option, I would have done it. I did recently find a used Evo 3 rally car drivetrain by Xtrac I believe it was, with differentials, for 30k. They don't make them new anymore however. If I would have found that before this all started, trust me I probably still would have done that. The problem would have been when I eventually broke something in that, replacement parts may have been exponentially more difficult to procure.

The nice thing about all the work I am doing now with the X-Shift Evo setup is that replacement options won't be exotic or rare, they have Evo drivetrain replacement parts on the shelf. In the long run, this is still the best path as I am sure I will inevitably break things at the power levels we're targeting, just more work to get to that point.

I am really looking forward to my first paddle shifts with Xshift; their parts are beautiful!

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Supporting Member
Jan 6, 2007
Central Valley, California
Hey all! Let me update you on some personal developments for the Eclipse project.

After I began filming for the 3D scanning video a few months ago, I realized quickly what a grand giant project scope this was opening up to. Building a motor, or welding projects here and there was one thing, but to design a tubular chassis on a chassis rig, and create a dry carbon body, would required more space than my garage/workshop would allow.


So since the last post, I sold my house and purchased a new place with a few acres to have space to build a proper sized workshop.

Since time and funds were tied up due to the escrow process, I wasn't able to make much progress on the new chassis.

It's been a few weeks now and my wife and I are still slowly getting unpacked, but I'm excited to get back into the garage again. The attached garage of the new place is no smaller than the old house, so I shouldn't be any worse off, but now we'll have the potential to build a new proper sized workshop. I hope we can get started on that next year.

Til that happens, I can focus on the staged launch of the C1 Eclipse again, where we'll return in a more stock chassis to begin with, and then evolve the aero body and chassis next.

To buffer the time I need to make progress on the car again, I will be sharing photos of new build items from sponsors and great vendors alike that have been continuously collected over the last few months.

Thanks for sticking with us during the dry spell. Our social media pages are working on gaining access to some exclusive Super Lap Battle competitor coverage, and hopefully find some more billet and carbon parts for the C1 Eclipse build to share with you all to keep you guys satisfied!

Lets start the return to posting with more billet! Evo Spec Performance has some custom parts you can't find anywhere else! We will be running their billet dual Evo 9 adjustable reverse cam sensor housings, which will make our cam sensors more reliable by solving a common problem on Evos of the exhaust manifold heat damaging them by turning the sensor around 180 degrees, and providing a neat little cover. They are also adjustable for dialing in the perfect base timing to account for variations with deck height changes over stock, which may or may not creep in with all the custom stuff we'll be doing with billet block and fire rings.


We also got a billet power steering delete bracket, which saves weight compared to the (now useless) heavy OEM bracket. Since almost every accessory has been removed from the engine, this just keeps the timing cover securely in place and belt protected.


stock bracket.jpg




Looking forward to sharing more soon!


10+ Year Contributor
Jul 11, 2009
Some where in, Colorado
Are these billet CAS housings compatible with 6 bolt engines?


Supporting Member
Jan 6, 2007
Central Valley, California

As the name implies, he started with Evo parts, but you can see he's got a few DSM specific parts as well. I am kinda intrigued by the idea of replacing a bunch of the 20 year old suspension bolts with titanium, but I'd probably need to provide him with the various sizes to make up a DSM specific "kit".

As for the cam housing, I don't believe he makes a DSM specific version, but, it wouldn't be a terrible idea to suggest. 7 bolt DSM housing is not adjustable and the fix for the adjustable Evo housing he did would be just as valid for those engines.

Maybe if a few ppl messaged him and he felt it was worth his time he might do it?
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Founder & Zookeeper
Nov 12, 2001
Newcastle, California
I've been trying to get him on board as a supporting vendor here, which would hopefully lead to a few more DSM-specific parts. Maybe you guys can let him know that he has some potential customers here who would love to support his efforts in this community. Be sure to mention the forum, otherwise he'll probably assume you're being referred from social media.


Supporting Member
Jan 6, 2007
Central Valley, California
Hey all!

I have been posting small teasers on social media (link in signature), but I think it is a good time to post a proper blog post update!


I won't be able to start building a new workshop for a good while, so will have to make due with the space I got, which ain't exactly slumming it. Just sucks to take a down grade from my last garage while waiting to build. I cleaned up much space as I could though around the car, and got started on the first major project: fitting the engine in the bay of the RS shell.


So this is the stock Evo idler mount.


Ruh roh..


This was everyone's first mechanic bolt trick right?



Ok, so this looks like a problem to me. Guides I have seen for this swap say to just "flip the 420a motor mount on and it bolts right on" but you can see the bolt holes are way over sized for the bolts from the Evo mount. This might be fine for a street car, but going down to just two bolts and having those two bolt holes over sized for the bolts going through it doesn't fill me with confidence with a 1000+ HP motor hanging on it. I reached out to Andrew from Frontline Fabrication and they will be CNC machining new motor mounts that will fit all 3 bolts and be properly sized. For the purpose of test fitting though, we'll just take a note and continue on.




We will also need to temporarily assemble the Xshift Sequential with the OEM Mitsubishi Evo transmission bell housing. We'll come back to the full assembly of the transmission, but again for now the goal is test fitting in the engine bay.

Was pretty stoked about that ^^ :rocks:

So, unlike the few Evo motor swaps that have been done, there are not a lot of guides with sequential transmission swaps in a DSM. I had concerns with the transmission housing fitting with the subframe, so I wanted to see (and photograph) that and the DSM OEM chassis transmission mount in relation to the evo mount on the transmission.


I actually was not able to get it even close to straight on my first attempt. Of note: The car currently has a GST/GSX subframe in it from the original Spyder chassis. I have heard the RS subframe was preferred for this swap due to transfer case clearencing concerns, but I wasn't expecting the OEM Evo bell housing to cause any conerns.


So, scratching my head a bit on how is it possible it could fit, I looked at the RS subframe, and (at this time of writing is still unknown if relevant or not) it looks like it have more space to fit the transmission. My reasoning:


Top ^^ GST/GSX subframe
Below RS/GS subframe

Maybe I am just crazy, but it seems like there is more space and a flatter protrusion on the RS subframe outside where the steering rack comes through the subframe opening (bottom side on both of these photos). The only way I can confirm this is to take the time swapping the subframes, but considering I need to cut the subframe up anyways to fit the transfer case, I would rather do that to the RS subframe for mock up, since it is likely I will move to a tubular subframe to fit the larger evo 8 Non-ACD transfer case. I chose this transfer case on the recommendation of Tim for its strength, LSD differential, and upgradeability in the future to a ACD transfer case with a Motec ACD controller. ACD adds complexity and they are more prone to issues so didn't want to start with it, but being able to fully control the lock up with the ECU is pretty neat.

As a side note, and just to pass along for those following the build who might want their own Evo swap, research has showed the Evo 4/5/6 transfer case is smaller then the 7/8/9 yet all 6 fit the evo 8/9 transmission. So if you aren't planning on road racing and pushing the car to the ragged edge, that may be an easier to fit option, but they are not interchangeable after the fact, since the two variants will change the drive shaft length and maybe axels? So, make the choice early on which transfer case you want to use and build around that.

With some photos out of the way and a few measurements, it was pretty apparent I was going to have to make some more space in the empty engine bay to fit this power train. The messiest project being the removal of the OEM transmission mount. These are the kinds of things I spend way too much time on (wife was getting mad at me after 4 hours in the garage grinding, so I know it was at least that long), but I wanted to damage the frame rail as little as possible. If I haven't mentioned it recently, the Spyder had actually welded 1/4" bar along the inside of the frame rails to strengthen them, so I'll redo that modification to this car. Knowing that I didn't want to weaken the metal by putting in cuts through with the angle grinder, I used angle grinder to get about half the way down the weld, and then used a dremel cut off wheel to go nearly through the metal. The last step was I then used a hammer and chisel to prey up the "aluminum foil thickness" metal holding the mounted to the rail.

There were 5 spot welds on the mount as well, so for those I used a spot weld cutter. If you haven't seen this before, you basically center punch the spot weld, and then this "drill" cuts the metal around the outside of the spot weld. You pry the part off and then either grind the remaining spot weld flush, or you can drill a hole in the replacement sheet metal panel and plug weld the replacement part. Since we are moving the mount completely from this spot, I cleaned up the frame rail and hit it with some self etching primer to keep from rusting over night.




I spent way too much time on this, but I was pretty satisfied having not cut into the frame rail with the angle grinder. I wish I could say the same for the spot weld cutter, I went bit too deep on that, but holes aren't nearly as weak as straight line cuts. Maybe I should finish drilling through the spot welds, dimple die them and just call them "speed holes" for chassis lightening :p


Next project, I will get the subframe swapped and try the engine in the bay again and see if I can start marking out where to weld the new chassis transmission mount location. Getting the engine in the bay without the pesky engine hoist would be a nice milestone to complete!

Til next time!
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Supporting Member
Jan 6, 2007
Central Valley, California
I am glad to see this swap getting documented. More people will save the 420a once this becomes common place.
Thanks! There are a plenty of reasons we chose to go through the swap, but if it also inspires some more swaps and saves more DSMs, keeping them on the road just that much longer, I am all for it. There is a little bit of info out there on youtube and forum posts from 15 years ago from guys that actually did the swap, but there wasn't anywhere that had the swap documented in a way that was easy to follow. I still think it is one of those "if you have to ask, you shouldn't do it" type scenarios, BUT having ours documented might help those who are on the fence about the project already take the leap. The making it fit part isn't that hard (I think!), and I plan to make some parts available that will make the swap even easier. Time will tell on both of those fronts! :)

All I know is that you're like 5 minutes away from me now so I need to go by and check out the car in person soon.
I am 2 doses vaccinated and ready for visitors, but you'll have to get in line behind all the family for a visit. I am scheduling Saturdays for visits, Sundays for racecar. If you want over on a Sunday, bring some overalls, and I'll have the fridge full of cold beer. If you coming Saturday just to look at the car and kick tires, the beer is on you :p

Jokes aside (or are they? :hmm:) I'd be happy to have you over. Like you said, you are right around the corner!

@snowborder714 is due over sometime this year to put in a little work with me; we'll have to make sure we get you over here for that visit too!


Probationary Member
Jul 13, 2020
Great to hear that man, I am doing my build for similar reasons. I am working on the srt engine swap and documenting it. I initially wanted to do an evo swap but Its too expensive for what I have going on. I have a gtr build going and I dont want the Dsm build to interfere so I decided on a budget swap. I still feel very inspired by this thread however, I cant wait to get back out in the garage and finish it more.


Supporting Member
Jan 6, 2007
Central Valley, California
Oh, btw we are AWD ready in the rear! (Sorry for posting this out of order, it should have been done in the above post).

Aside from the fact I didn't clean anything up, this process all took place in a weekend before I had moved to the new place so I didn't document it as well as I would have liked, so enjoy the photo dump and hopefully next update I do a better job with the photos. Since this has been done countless times on Spyders/GSTs please excuse the lack of detail, but the process of AWD swapping the car is the same for the RS, or pretty dang similar.

I was concerned there might be some differences in the rear of the 420A chassis vs a 4g63, and maybe it is? While swapping the 4 longer bolts of the AWD subframe into the car, the front bolts actually didn't have the re-enforced stand offs the GSX had. So I ended up using the two longer bolts just in the rear. Maybe that is common knowledge? but I thought I be swapping all 4 longer bolts and I didn't need to. Random FYI with my experience, but someone please correct me if I am wrong.


You can see here there is no raised reinforcement on the front bolt like there is for the rear bolt (second photo)


Hanging down too low, so I just used the shorter bolt I pulled from the rear.




I will have to clean the back side of the car up good like I did the front and only then will I get to showing the fun we have in store for the rear differential, but that is it for this post! See ya!


Supporting Member
Jan 6, 2007
Central Valley, California
Best I can share for an update is the the land for a new workshop is under contract but interest rates and adulting sucks. I need space for a chassis rig and lift to build the necessary roll cage, and didn't want to send the car off to another shop to do it. The build process is a huge part of the fun and I like to do things right, so progress has been paused til the finances for the shop are concluded. This is the last time we plan to move the car, so the shop needs to have all the space and rooms to do what I want with the car.

Anyone is free to ask questions about the car if anything peaks their interest. Sorry there isn't much new in the way of progress. Only thing lately car related is billet part collecting.



I'll be sharing a build blog of the workshop build too once that starts. Hopefully we're not too far away; I've already designed the building in CAD and have a supplier!

Other than that, I learned how to fly an airplane this year. I'm signed off for solo but haven't taken my private pilot's exam yet. It isn't a race car, but it's still has plenty of aero, has high g forces, and goes fast!

Solo 3.jpg

Solo 4.jpg

Thanks for the bump, it's a good reminder folks other than me want to see the next evolution of the car!
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