LFX Engine Swap (GM V6) at GWR

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Ryan @ GWR
Posts: 497
Joined: Fri Oct 17, 2014 11:37 pm

Re: LFX Engine Swap (GM V6) at GWR

Post by Ryan @ GWR »

Just before the holidays hit I was deep in connecting hoses and wiring for the final time. Bit of a mess while sorting through what still needs to be figured out, needs to be tweaked, etc. but here's a quick snapshot of about where we are at the moment:
LFX_inprog.JPG
And, decided to spring for some trick fittings to go hand in hand with the quickly removable front end design, still waiting on parts to arrive but for now here's a teaser of the dry break fittings that will be going on the power steering lines:
LFX_PSdrybreak.JPG
Ryan @ GWR
Posts: 497
Joined: Fri Oct 17, 2014 11:37 pm

Re: LFX Engine Swap (GM V6) at GWR

Post by Ryan @ GWR »

Doing some napkin math for other fun places the car may fit in.

Looking at NASA, when you move above the complicated mess of the lettered classes on up to ST/TT 1, 2, 3 things get much simpler. With a good bit of power taking the tighter-regulated TT4 out of the question it gets even simpler. Basically take a dyno and weight baseline which then applies modifiers for certain mods and you end up with an adjusted power/weight ratio and that's that. Everyone racing in the class has the same adjusted ratio. Obviously this favors a wide torque curve, and this motor should be great for that.

TT2 cars have an adjusted wt/hp of 8.00:1 or more (up to 10.00:1 which is TT3)
2300 lbs with driver / 300 whp = 7.67:1
Relevant adjustments:
Comp weight over 2200, less than 2599 = -0.2
Tire size 245 or smaller (DOT approved) = +0.7 or Tire size 275 or smaller (DOT approved) = +0.3
Non-production vehicle = -0.4

A note on the non-production vehicle bit.. have to take that due to the tubular front subframe, but this comes with some benefits. First, I don't have to take the -0.2 for cutting the rocker for exhaust routing for production vehicles, so it's really only -0.2 more than if it was considered a production car. But more importantly, with it considered a non-production car there's no concern about the tubular/removable front nose being OK.

So, with adjustments, 7.77:1 with 245 tires or 7.37:1 with 275's

Ballasting up to 2375 lbs with 245 hoosiers puts me at an est. adjusted 8.01:1, right at the pointy end of TT2.

TT2 is full of Corvettes and Vipers... always love a challenge! :twisted:
Ryan @ GWR
Posts: 497
Joined: Fri Oct 17, 2014 11:37 pm

Re: LFX Engine Swap (GM V6) at GWR

Post by Ryan @ GWR »

Continuing to wait on a few more parts to arrive, so I took some time to get some of the suspension bits assembled.

Pressed out all of the old polyurethane bushings and now installing for evaluation a spherical bearing kit for the factory control arms from a shop up in Canada.
lfx_bearings.jpg
Spherical bearings within the press-in sleeves:
lfx_bearings2.jpg
I've run into a couple snags with some of the parts in the kit, shot some feedback to them to get those bits resolved instead of having to machine my own solutions, and hopefully we'll get things sorted out. Nevertheless, the majority of the kit is installed and ready to rock.

Also going into the arms are Bauer extended lower ball joints and V8Roadsters rebuildable front upper ball joints:
v8r_balljoints.jpg
Finally, I'm replacing the rear upper arms with V8R's tubular Pro series arms. Feedback from Steve about what they've seen on other cars, the rear upper arms are the ones responsible for wheel hop and other funkiness when putting big power down as that factory arm twists with enough torque. The tubular arm solves this, and the pro series has spherical bearings to match the rest of my arms.

Oh, and in my recent powdercoating frenzy I had all the factory arms done.
thepass_arms.jpg
Ryan @ GWR
Posts: 497
Joined: Fri Oct 17, 2014 11:37 pm

Re: LFX Engine Swap (GM V6) at GWR

Post by Ryan @ GWR »

While waiting on the last fittings to arrive, this past week I've been working on wiring plans in the evenings.

Because race car I'm pulling the entire Miata harness on the chassis side as well and will make a new harness for just the essentials. For the record, if this was a street car with many more factory systems I would keep the factory harness and just add things as needed. But since that's not the case, there's some planning to be done here if I want to wire everything up in one nice clean harness.

The engine harness itself has already been set up nicely for my needs by V8R. They trimmed out anything unnecessary, converted it from auto to manual, added an OBDII port for me and extended a few wires at my request. They also fused anything that needed it and added a main relay. All that's left for me to do on that side is carry a few voltage wires from the cabin/battery over to the engine side.

But, that doesn't get me out of the woods. I still need to sort out a chassis harness which includes several systems like fuel, ignition, etc. as well as the Racepak dash plus the sensor module for the dash. I also need a cooling fan circuit, and I need to get the OBDII port and the drive-by-wire connector into the cabin. To make things easy to service/remove, almost everything will pass through a single bulkhead connector in the firewall.

One unknown I ran into during planning was the question of how much info the digital dash can pull directly from the ECU via the OBDII port. Anything the dash can get straight from the ECU saves me time and wires. The guys at Racepak couldn't make any guarantees, they said you really just have to plug the dash into the car, start it up and see what data it can pull. Well that's great except I can't start my car yet - I need the wiring done before I can start it... but if I want to do the wiring all at once and not have to hack it up and add stuff later I need to know this answer before I do the wiring. Gotta love catch-22's.

Sean had a great idea for a solution - rent a V6 Camaro and wire the dash up to it.
DACB848E-2783-46D3-8BBD-1272BCDD397B_zpslorh3u26.JPG
Turns out it can pull quite a bit of info. I don't need most of it, but here's the full list of what the dash is getting from the OBDII port - noteworthy items that I'll probably be displaying on the dash in bold:

Fuel system status
Engine RPM
Vehicle speed
Calculated engine load value
Short term fuel % trim - Bank 1
Short term fuel % trim - Bank 2
Long term fuel % trim - Bank 1
Long term fuel % trim - Bank 2
Intake air temperature
Intake manifold absolute pressure
Timing advance
Engine coolant temperature
MAF air flow rate
Oxygen sensor Bank 1, Sensor 1
Oxygen sensor Bank 1, Sensor 2
Oxygen sensor Bank 2, Sensor 1
Oxygen sensor Bank 2, Sensor 2
Run time since engine start
Distance traveled with malfunction indicator lamp (MIL) on
Fuel pressure
Fuel rail pressure (diesel)
Fuel level input
Fuel type
Commanded evaporative purge
# of warm-ups since codes cleared
Distance traveled since codes cleared
Evap. system vapor pressure
Barometric pressure
Ambient air temperature
Control module voltage
Absolute load value
Command equivalence ratio
Throttle position
Relative throttle position
Absolute throttle position B
Absolute throttle position D
Absolute throttle position E
Command throttle actuator

In addition to the above bolded items, I'm adding temperature sensors for engine oil, transmission, differential and power steering fluid. These four will tie into a Racepak universal sensor module which transfers the data from those sensors to the dash via one cable. Between the stuff above and these four added sensors the dash should be able to keep an eye on everything important. I can set up warnings on the dash for any of these inputs, so I can focus on driving rather than worrying about checking gauges.

I'm disappointed that oil pressure isn't on that list. The ECU monitors this, but it appears it doesn't send that info to the OBDII port. I'll need to wire up a second OP sensor or figure out if I can piggy-back on the factory sensor's wires. Not sure yet on that front, but overall some good info gained and I can finish up my wiring plans now.
Ryan @ GWR
Posts: 497
Joined: Fri Oct 17, 2014 11:37 pm

Re: LFX Engine Swap (GM V6) at GWR

Post by Ryan @ GWR »

With the last of the fittings arriving yesterday, today I completed everything that carries fluids in the front end. Now that I've finished that up and know for certain how it's all going together I can finally cover each system in its own post.

Power Steering

We begin with V8R's power steering kit. Included are fittings/lines to replace the hard lines that run along the rack itself with steel braided lines as well as fittings and a high pressure braided line for pump to rack. The kit leaves it to the user to sort out the low pressures lines (usually rubber) and reservoir (I've heard the factory Miata unit can be used), so that blue 180° hose barb fitting is supplied for the exit from the rack.
LFX_PSkit_zps4y9g4owu.JPG
I used everything above except the hose barb fitting because this car will use braided lines throughout.

Removed the old lines from the rack and spent a good deal of time cleaning the rack up. The power rack I got from a donor car seemed to have been competing for the coveted title of thickest layer of grime, but it’s shiny now.
56BE0661-DBD2-4EC9-AF33-8415F9B1A5D7_zpszphhfees.JPG
Here’s the rack with the V8R lines added. Also pictured is the early version of the rack to cooler line I made which I later added the in-line dry break to:
4B02A332-C334-45B8-867B-D8A110AB9C8B_zpsm5bf08uf.JPG
Closeup shot. This bunch sit close to the pan once installed so best to leave them loose and adjust the angles once both the engine and rack are in place:
404BCA29-CFFC-43F6-A6EA-6328773430AC_zpsbw0xjktt.JPG
Pic of the power steering pump. The black threaded outlet goes to the rack which V8R supplies a fitting for (that’s what I’m holding in the photo). The port above that is the inlet from the reservoir. That port has a barbed end for a rubber hose in the stock GM form, but as seen in this pic I removed that and drilled/tapped the hole to adapt it to an AN fitting:
E765680C-C745-4453-8DB2-DFCED6FD40DC_zpssefpevkv.JPG
A note on the power steering pump pulley -
To remove the pump from the engine you must remove the pulley from the pump first. This took us a combination of parts from a rather comprehensive pulley puller kit, something most home garages may not be equipped with. Reinstallation of the pulley is equally difficult. I’d recommend leaving the pump on the engine unless you absolutely have to remove it. However, there is a complication if you’re going to add an engine oil cooler; to remove the factory oil filter housing you have to remove the steering pump first because the filter housing’s bolts are too long and can’t be backed all the way out with the pump in place. For shame, GM! Later, when I installed the Keisler oil reroute plate in place of the stock filter housing I swapped two of the factory bolts out for shorter ones and now the plate can be installed/removed with the steering pump in place. At any rate, if you need to remove the filter housing you’ll have to take the pump off at least once.

Now back to our regularly scheduled programming…
The next piece to the puzzle was the steering fluid reservoir. The reservoir needs to sit higher than the pump as it is a gravity feed. The pump’s position on the motor is high enough that there was a good bit of head scratching and lots of looking around at various reservoir options/shapes/etc. to figure out what to do. The solution I came up with uses a Moroso reservoir mounted directly to the top of the pump NASCAR style. This eliminated the need for a hose and guarantees good flow from the reservoir to pump. This reservoir is actually intended for power steering so it has the appropriate internal baffles.

I don’t have a pic of the reservoir by itself but you’ll see it in following pics. The reservoir had an AN bung in the bottom for the drain so with a couple fittings the pump was set up for the direct-mount:
BB854EE8-FB48-412D-A037-214792F5811E_zpsrpkau5o4.JPG
To hold the reservoir in place requires a bracket :) Always up for challenging myself, I decided to make it from aluminum. Here is an in-progress pic about 80% of the way done, just before tack welding the two halves I made together:
F4DD01FE-E31F-46D7-8A64-FEB5E4ED7A36_zpsgwss29pz.JPG
It turned out to be a funky looking little thing but it’s nice and light, piggy backs on existing factory bolts, and does just what’s needed:
4EF0270B-DC3F-4638-B0B4-3372746359A7_zpsjzvufqtk.JPG
Here it’s mounted up with the reservoir. Note the factory oil filter housing is still in place behind there, but that is removed later for the oil cooler:
D36BB589-6998-4301-B588-AF385A0C1FB9_zpsy6fhuvax.JPG
The final piece in the power steering system is the cooler. Most cars doing any sort of performance driving will need one, you don’t want this system overheating and spraying flammable fluid around the engine bay. If you’re doing a more standard street setup with rubber lines there are lots of affordable cooler options with barbed ends built in. For this car I chose Earl’s 40700 cooler, which is a 13”x2”x2” unit, with -6AN ends. I erred on the small side to keep weight down but Earl’s stuff has efficient cores so I think it will do the trick. I’ll be monitoring fluid temp so I’ll know if it is sized well or needs to be upgraded:
32352005-DBB2-4D90-A077-C51DDF5C32AB_zpsum1samez.JPG
Back when I was making the removable nose I made the brackets to hold the cooler in place. With the cooler, pump and reservoir all settled in all that’s left is to connect the dots with the lines. Embracing the idea of having the whole front nose section quickly removable, I picked up a pair of Radium -6AN dry break fittings for the power steering lines:
7C075CF5-D0DC-49ED-AE73-0FF3025884E7_zpssc2cmohs.JPG
Long line below is cooler to reservoir, with the dry break junction fixed to the reservoir side. The short one is half of the rack to cooler line:
3DF54378-B6ED-4924-8B7F-BB56515AF132_zps4sm00mgd.JPG
Here’s the other half of that lower line, I had already fixed it to the rack and didn’t want to remove it for the last pic. This section has a fire sleeve since it's in the vicinity of the exhaust:
F4CF140D-5AE1-4008-BBB9-D77829B5DB6F_zpssnrzrfl4.JPG
Final setup installed:
81686093-065F-4A07-9D0B-41C1E60C6AE9_zpshbhelmx4.JPG
That concludes the power steering setup. Tomorrow I'll write up the oil cooler system.
Ryan @ GWR
Posts: 497
Joined: Fri Oct 17, 2014 11:37 pm

Re: LFX Engine Swap (GM V6) at GWR

Post by Ryan @ GWR »

Oil Cooling

First the hurdle. The factory oil filter setup is a cast aluminum housing that bolts to the left side of the block and extends up to hold the filter canister up near the fill cap. You can see the housing just forwards of the dipstick:
LFX stock pic 1_zps9fzxlafe.JPG
LFX stock pic 1_zps9fzxlafe.JPG (73.27 KiB) Viewed 8175 times
To run an oil cooler we need an inlet and outlet for the lines, but a traditional sandwich plate won’t work here because of the unique shape of the ports where the block and housing meet:
D903E659-2972-4CE2-A207-E701CEA28868_zpsq6aodved.JPG
Conveniently, Keisler Automation has been working on a solution. Here is their oil reroute plate:
571CFB85-1B97-4AF5-A88B-A14B35A8AB59_zps5sm2uiji.JPG
This plate has a pair of M16x1.5 ports to which I added the metric to -10AN adapters. It also has an ⅛ NPT port for a sensor, but I found its location to be too cramped beside the larger fittings (and the GM oil pressure sensor is M14x1.5 anyways) so after this pic was taken I plugged that port and put the sensor in the remote filter plate:
A5593278-B939-4CE7-9F1C-5E950DC3541D_zpsgmlzeiuf.JPG
As I mentioned in the power steering post, the factory oil filter housing can’t be removed without taking the steering pump off because the factory bolts are too long. There’s no getting around this the first time, but when installing the Keisler plate I switched the two forward bolts to shorter ones - this makes it possible to remove/install the plate with the steering pump in place. I forgot to write it down but I believe I used M8x1.25x25mm:
AA3FD5E9-8AD3-4C99-A7FA-9408039AD8DD_zps1todpfoj.JPG
With the in/out for the hoses sorted all that’s left is a remote filter and a cooler. For the remote filter adapter it was important to me for it to be mounted to the engine so that removing the engine requires as little disassembly as possible. I played with a few locations and came up with doubling up the filter adapter on the same bracket that holds the power steering reservoir. Here’s the filter adapter mounted up to that bracket (now powdercoated black) with the steering reservoir not yet mounted:
EBBC51AC-9285-474D-94E6-78B7024111E7_zpst92l3vqu.JPG
Here it is with the steering reservoir in place. The filter location ended up mimicking the factory location a bit. Oil changes will be a breeze:
DB2BEC79-FF1B-480F-A640-789E9B41E302_zpsuctvojta.JPG
Now for lines and the cooler. For the cooler I chose another Earl’s unit - same depth and length as the power steering unit but taller; 19 rows instead of 7.

Just as I did with the power steering system, in order to make the entire nose assembly quickly removable I chose to add dry breaks here. Staubli -10AN units for the oil lines:
DA73C7A0-F6CB-463B-9195-3DF5F26B7420_zps4zkiwjwx.JPG
Here’s the full system just before final install. I fit the dry breaks directly to the cooler so that the feed and return lines remained one line each rather than being split into two. Fire sleeves on the portion of the lines that are anywhere near the exhaust. The short line is oil plate outlet to remote filter inlet and the long lines of course go to the cooler:
3261EA19-D970-4A8F-8E22-D0FF3E24541B_zps69fjcdqs.JPG
Installed:
87BF020F-E03A-4C18-9CF5-4673A808641A_zpshrut50wu.JPG
Ryan @ GWR
Posts: 497
Joined: Fri Oct 17, 2014 11:37 pm

Re: LFX Engine Swap (GM V6) at GWR

Post by Ryan @ GWR »

There's still a bunch of assembly to be done before it's driving (rear end, suspension, interior, etc.) but we're close to first test start. All that's left is wiring... not a small thing but I can feel it getting close!

Current view from the front:
A878583D-A9C7-4450-93D7-51785A817D7A_zpsztykxt3x.JPG
Ryan @ GWR
Posts: 497
Joined: Fri Oct 17, 2014 11:37 pm

Re: LFX Engine Swap (GM V6) at GWR

Post by Ryan @ GWR »

Apologies for it being quiet for a little while, I've been spending long hours building the wiring harness. I wanted to be rid of the hacked up factory wiring mess once and for all so I chose to take the long road and removed every wire from the car, because now was the right opportunity to take the extra time and learn how to build good motorsports wiring from the ground up.

For now, here's a pic from way back on step 1 with wires laid out for the new chassis harness:
F9F0F166-2E84-403D-8E48-34BA77DA94B6_zpslt3kn7zi.JPG
Chuck H
Posts: 154
Joined: Fri May 18, 2012 6:28 am

Re: LFX Engine Swap (GM V6) at GWR

Post by Chuck H »

Absolutely loving following this build. Your car is going to be amazing when it's done! 8)

Just one question. At what point does it cross the line from "swapping an LFX into a Miata" to "building a whole new car around an LFX"? :wink:

Can't wait to see the final product and the track results!
2019 Arctic White RF GT-S
SmartTop, coilovers
Ryan @ GWR
Posts: 497
Joined: Fri Oct 17, 2014 11:37 pm

Re: LFX Engine Swap (GM V6) at GWR

Post by Ryan @ GWR »

Chuck H wrote:Absolutely loving following this build. Your car is going to be amazing when it's done! 8)

Just one question. At what point does it cross the line from "swapping an LFX into a Miata" to "building a whole new car around an LFX"? :wink:

Can't wait to see the final product and the track results!
Haha that's a fair point. I certainly went into it not having plans to do some of the things I later chose to do. Perhaps I'm somewhere in the wide and expansive gray area between the two? :lol:
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