LFX Engine Swap (GM V6) at GWR

Miata Parts, Intakes, Superchargers, Headers, Exhausts, Shocks, Springs, Sway Bars, Brake Kits, Autocross and track mods.
Ryan @ GWR
Posts: 497
Joined: Fri Oct 17, 2014 11:37 pm

Re: LFX Engine Swap (GM V6) at GWR

Post by Ryan @ GWR »

LFX Price List

One of the big questions everyone has had since the new drivetrain plans were announced was "what does it cost to do this swap?" I couldn't accurately answer that until the swap was done. When we're 'keyboard racing' and comparing swap options it's all too easy to add up the big ticket items and figure that gets it in the ballpark, but anyone who has done a swap knows that there are dozens of items you don't think of and they all add up. Therefore, just about every swap out there costs more to really do than people guess. To help demystify this subject for the LFX, I promised I'd post the real costs of the swap when done.

That time has come! However, a lot of details on the HyperMiata are irrelevant for the next guy doing a fun street/track build. So, to give a good representation of an "average" swap I've put together the cost list below:

LFX Swap Items/Costs

I trimmed out the pure race car stuff and subbed in options that I'd be choosing for a good average build. The list assumes minimum fabrication ability and includes any off-the-shelf options that make the swap easier, such as V8R's plug and play radiator and ECU with tune. Yes, you could definitely do an LFX swap for less than this list shows if you trimmed it down to the necessities and did a budget version of some items. Costs for fabricated items like the coolant hard lines and the exhaust are estimates that assume having the work done at a shop.

The only fabrication item not listed is the cutting of the rear corners of the engine bay and then welding in the frame rail corner caps - but the cost of those caps from V8R are listed. I think most DIY guys would tackle this bit in their garage.

Not listed here is a solution for gauges. The race car got a digital dash, a custom wiring harness and an array of extra sensors - not stuff you need for a street car, but in a way it made the job a little easier rather than trying to get the stock gauges to play nice with the new electronics. V8R lists a set of gauges in the works on their site, so there may be an easy solution for this in the future.

Finally, I've included all of the random incidentals that I came across - stuff like the new GM speed sensor, clutch slave, front differential bushing etc. etc. (all things that turned out to need replacing in the parts I got from the junkyard). These unplanned items will be different for each person, but I'm including all of mine to serve as a realistic and comprehensive example for the swap.
Carguy123
Posts: 6
Joined: Thu Nov 30, 2017 6:43 pm

Re: LFX Engine Swap (GM V6) at GWR

Post by Carguy123 »

A question on your clutch, flywheel.

As i was rereading the thread it struck me at how thick the flywheel was. You mention it needed to be that thick to replace the flex plate, etc. Are the engines different Automatic & Manual?

None of the Camaro flywheels I've seen appear to be that thick. If you'd gotten a manual engine could you have just used a stock aftermarket unit?
Ryan @ GWR
Posts: 497
Joined: Fri Oct 17, 2014 11:37 pm

Re: LFX Engine Swap (GM V6) at GWR

Post by Ryan @ GWR »

The engines are the same between manual and automatic so there's really no avoiding needing the thick if I want to run SPEC's flywheel. Because we're talking about the "base model" V6 Camaro, I actually don't know of any other clutch MFGs offering an aftermarket clutch for this engine/trans. If more option sprout up in the future I'll be interested to see if/how they differ from this one.
Ryan @ GWR
Posts: 497
Joined: Fri Oct 17, 2014 11:37 pm

Re: LFX Engine Swap (GM V6) at GWR

Post by Ryan @ GWR »

We have the shifter feel/return-to-center issue finally pinpointed!

Trans #1 had a seized pivot on the shift rod from the start. We just didn't know it because it was our first experience with a trans from this family. With trans #2 (and MV5 I bought to take comparison measurements from) and trans #3 (an MV7 to replace the one in this car) in our hands it became immediately clear that these pivoted differently than I recalled #1 doing. With the car back in the shop and on the rack I was able to disconnect the shift linkage last night and confirm the difference.

That pivot allows for the off-axis motion the shifter makes as it moves side-to-side. Without the pivot the shifter is binding with just about any motion.

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

Re: LFX Engine Swap (GM V6) at GWR

Post by Ryan @ GWR »

Cooking up a bunch of improvements, currently in crunch mode because I'd like to get the car out to Streets of Willow in just two weeks (!!). Will have updates for you guys when I get some time to sit down, but for now here are a few more great pics that surfaced from Superlap Battle, courtesy of Motolyric:

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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 »

Ok time for some updates.

2017 was a big success, and I'm really happy to have some solid baselines and results in the bag. Now, it's all about refinement and MORE in equal parts. In Decemeber with SLB fresh on my mind I did a fresh examination of the car and rulebook and identified anywhere I had room left on the table to maximize performance.

Big on my list is to really hone the chassis and suspension to the maximum possible, within the Limited class rules of course. This goal encompasses both the systems on the car as well as the track-side setup and tuning. A car with all the potential in the world won't do much without putting in the testing and tuning hours to get everything working in unison.

Enter 949 Racing. They need no introduction, these guys are good at a lot of things, but perhaps what they're the best at is setting up a car and extracting every bit out of it. That's not a small talent. Breaking new ground in an underdog chassis, I think a key to success is going to be in getting more out of the car than the competition, and there's a lot I can learn from these guys.

With 949 on board comes a change to the suspension to extract everything possible allowed by the rules; GTA Limited allows 3-way shock adjustment. Ergo, XIDA triples:

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I quite like the look of the coaxial top mounts in the engine bay:

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Doing sub-1:50's at Buttonwillow has me looking for more roll resistance, even on the street tires. With the downforce I'm seeing race tire cornering loads, and scraping the outer sides of the aero on the track. There's no avoiding I need to go stiffer. The XIDAs come with another jump up in spring rate from my previous setup.

The front sway bar also gets an update. It was one of the last things that's carried over in the build from pre-2017. At GWR we've been working with Karcepts, who make some really nice sway bars for the ND and a couple other chassis. I took some rough measurements and ran a few numbers and worked out that I just might be able to adapt some of the pieces of their ND sway bar to put together a 3 piece NASCAR style bar for this car. I ended up ordering a pair of their beautiful ND arms and their brackets/bushings for the S2000 because the measurements for those looked like they would work best, and a custom Speedway center tube:

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Many times in and out figuring out dimensions, checking full range of motion, etc. Had to make a pair of adapter brackets for the sway bar brackets.. here everything is about 90% sorted but I needed to move the endlink bracket on the control arm forwards to shift the pivot slightly. No problem there because those lower arms need to go anyways...

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In my factory lower arms I've been running an evaluation kit of press-in spherical bearings that replace all the bushings. Great concept, but unfortunately it turned out to not be the best execution in the product. Most people didn't know that in the final week before SLB I discovered a critical problem in the bearings in the rear lower arms so I ran SLB (and Chuckwalla after that) on factory rear lower arms with 100k mile factory rubber bushings - because it's what we had available at the last minute. Definitely not ideal. Time to get those arms out of the car and replace the front lowers as well to get the last of those bearings out and move on to something trouble-free.

V8R tubular pro series arms arrived. These arrived in bare steel so I could do the custom endlink mount on the fronts:

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Then they went off to powdercoating to get finished up. Far more robust bearings in these, strong, awesome:

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Just about everything is installed and sorted out at this point, and I'd love to show some pics of everything installed buuuut can't really do that right now because this is the current state of affairs:

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Yep, two weeks to go before first track testing of the year, still cranking away on things feverishly ;)
Ryan @ GWR
Posts: 497
Joined: Fri Oct 17, 2014 11:37 pm

Re: LFX Engine Swap (GM V6) at GWR

Post by Ryan @ GWR »

Pic to illustrate why more roll stiffness is needed. This is just a steady corner, not coming down off a bump or anything. Dragging the outer corners of the aero on the ground. At Chuckwalla I could actually hear the scraping as I would turn into "dropzone" at the end of the back straight. I run disposable delrin sliders on the underside of the splitter so I don't destroy it, but am wearing through those quickly:

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During post-season inspection I also found scrape marks on the outer front corners of the side skirts. Not sure what corner that was happening in, but definitely a sign of lots of roll.
Ryan @ GWR
Posts: 497
Joined: Fri Oct 17, 2014 11:37 pm

Re: LFX Engine Swap (GM V6) at GWR

Post by Ryan @ GWR »

Last weekend, with two weeks to go before the first track testing of this season, I was debating whether I should swap in transmission #2. From my post back in January, when trans #2 arrived I was able to confirm that the shifter rod was supposed to pivot - and that the pivot on trans #1 in the car was seized. That's been the cause of my clunky/stiff shifter feel, which is one of two transmission issues I've been dealing with. Issue #2 has been with clutch disengagement, and this one everyone has noticed because you can hear the gear grinding in my videos. Having checked out everything outside of the transmission, we feel confident the issue must be in the relationship between the throwout bearing and the clutch. Can't know for sure without getting in there. January was stuffed full with getting all of the updates/changes in the suspension and brakes on the car because so I can start out early season testing with all of that in place, so this is the earliest I've had a chance to turn attention to the transmission.

I already had measurements for the transmission side of things from trans #2 sitting on the bench. I even bought an MV5 (Camaro version of the transmission) to take the same measurements and confirm first-hand there weren't any differences between the two variants (I'm using the Cadillac MV7):

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To get the full picture, we also needed to measure the clutch and flywheel. Based on the nature of the clutch disengagement problems, we expected that when we got in there we would find the throwout bearing is too far from the clutch fingers, and that would be an easy fix - you just shim the slave/TOB assembly to the correct position. On Sunday I dropped the engine/subframe/trans:

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I expected I'd pull a long day and have everything back in the car by night with the TOB shimmed to the correct location. With everything out, I measured the clutch and flywheel height, and that threw a wrench in the plans. The TOB wasn't too far from the clutch, it was too close, and by a massive amount. With the trans bolted to the engine and everything at rest, the TOB would already be compressing the clutch fingers by 0.200" (and the fingers only have an intended range of motion of about 0.400"). So the problem is the opposite from expected; I'm over-stroking the clutch.

Left everything on the ground and called SPEC Monday morning. Based on their notes, the stack height from flywheel/crankshaft surface to clutch fingers for their clutch/flywheel assembly should be 3.800" +/- .005". Mine is 4.1"

With the window of time to get everything back together quickly shrinking (The car still needs to visit the alignment shop and the dyno prior to the track) I shipped the clutch and flywheel back to SPEC. They're working on it now, no word yet but it would appear they manufactured the flywheel with the wrong thickness.
Ryan @ GWR
Posts: 497
Joined: Fri Oct 17, 2014 11:37 pm

Re: LFX Engine Swap (GM V6) at GWR

Post by Ryan @ GWR »

Corrected items arrived back from SPEC yesterday. They say it was a machining error inside the pressure plate that affected the pivot. As soon as it arrived I measured things to verify, finger height from crank surface is now 3.85x" which leaves the TOB about 0.030" of a gap from full compression. We're in the ballpark now.

Reattached engine and trans last night. Should have the engine back in the car today, at which point I'll be back on-track where I was a week ago, but now with one week to do two weeks of stuff. Still holding my breath, I won't declare the transmission issues fixed until I've actually driven it on the track, but if they are then it was all worth it.
Ryan @ GWR
Posts: 497
Joined: Fri Oct 17, 2014 11:37 pm

Re: LFX Engine Swap (GM V6) at GWR

Post by Ryan @ GWR »

Drivetrain is back in the car as of today, filled with fluids, test fired, bled, etc. So far I can say for the first time that the shifter feels great! Return to center in neutral feels natural and all of the "clunky stickiness" I had before is gone now. The shift rod pivot was definitely the problem there. Fingers crossed that the clutch engagement issues are equally fixed!

Didn't take any pics today but in other news, SuperStreet just released their coverage of Superlap Battle LINK HERE so here's a shot from them of the engine bay, which is where I've been spending my evenings lately:

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