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The Buchka 242 Fake Racecar

When you already have a tube chassis, Indycar transaxled, twin turbo V8 242, it would be rude not to use Inconel for the entire exhaust system!
 
When you already have a tube chassis, Indycar transaxled, twin turbo V8 242, it would be rude not to use Inconel for the entire exhaust system!

Seconded!


Got some more parts in the mail. Ordered a couple v-band flanges for the downpipes:
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Got a few really slick oxygen sensor bungs from Reid Washbon. It's the little details and these things are primo. Also came with a free notepad:
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Lunched this bearing taking it off. Cost me $80 and a bruised ego. This is the back business end of a torque tube from a C5 vette and is part of what makes the xtrac magic happen:
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Pulled the drop gear cover off the xtrac to machine a hole in it for the reverse lockout. The small post to the left of the center shaft is the reverse selector shaft, this is what the lockout mechanism blocks from moving.
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The insides of this gearbox are amazing. It's like a jewelry box.
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Had to stop and check wipe a few times during this operation. Screwing it up would have been grounds for ritual suicide.
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Then Karl and I had a potential Corona exposure event so we've been locked in the apartment for the last week. I took the time to order up a mountain of laser cut brackets that arrived today. I've been using sendcutsend.com for the last few orders and they really kick ass. Super clean cuts, excellent prices, and crazy fast delivery. This entire pile took four days from order to arrival.

This heap is mounting brackets for the dash display, current sensor, yaw sensor, heat exchangers, and wastegate actuators, end tanks for the rad, oil cooler, and intercooler, main hoop bulkhead panels, wiring bulkhead brackets, and weld-on rivet strips for various things.
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What are the advantages of an inconel exhaust?
Pro: Super light, heat resistance properties.
Cons: PITA to work with (apperently). Very expensive.

F1 (and some others high end race cars) exhausts at Inconel 625. They can be made extremely thin and therefore light, and also because of the great heat resistance properties.

Also used in nuclear reactor cores and spacemachineshiprocketthings
 
I love this thread, its such a great read........ Oh and by the way, completely by coincidence, I just bought a B8444s to swap into my 240 wagon. :roll:

https://imgur.com/nfUzXAk

I hope you've got the skills to pay the bills. It's an incredible motor for a 240, but its so hard to make it work. It's also easy to find and cheap to buy since the transmissions grenaded on so many of them.

Keep us up to date!
 
I love this thread, its such a great read........ Oh and by the way, completely by coincidence, I just bought a B8444s to swap into my 240 wagon. :roll:

https://imgur.com/nfUzXAk

Thanks! You should make a project thread, I'd love to see your progress.

Everything you guys do is the sexiest thing ever

That's debatable, but thank you!

Ran low on motivation for a stretch but we're back at it now. I had the previous week off in between jobs so I made a big push to finish up the control arms.

I was a little worried I'd gone overboard on the fixture for the arms but after using it for the past few days I actually could have made it a bit more rigid. Welding distortion can exert tremendous force and the 1/4" aluminum base plate does get a little bendy at times.

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The outer pivot is located on the smaller common plate. The larger plates are made in unique pairs for each side of the car. The bearing cups get pressed on to some brass standoffs that both locate the endpoint at the right height and keep the ID from distorting during welding.

Arm construction is fairly simple. 4130 tubes and spherical bearing weld cups. The lower arms have some sheet metal gussets where the damper mounts will get welded on.

Took a few arms to get the process dialed. All the tubes are larger OD than the height of the bearing cups so the ends all got smashed down in the press, then trimmed with the notcher until they fit nicely.

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Welds got progressively nicer as i got into the process. I don't fabricate stuff for a living so I'm really happy that I can maintain reasonable consistency even after a month+ hiatus from the TIG.

So far I have six out of eight complete less damper mounts. The remaining two rear upper arms are a bit more complex to accommodate some less than ideal damper packaging. They will get some additional taco gussets for peace of mind. I fabricated this forming tool out of literal trash I found laying around the shop. It's not the slickest thing to use but I'm only forming a handful of gussets so it does the job.

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Welded up the yaw sensor mount.
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Started adding some paneling.
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Made some jack-screw doodads for the xtrac. Everything on this gearbox has threaded inserts to aid removal, pretty slick.
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Picked up a flush mount fuel filler.
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Spent a bunch of time welding and blending this sweet mounting bracket for the stack dash, then i sat in the car and realized the rim of the wheel blocks the view of the entire tach. Derp.
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Picked up this carbon diffuser from an NSX GT3. It's a bit rough but all the bad parts will get trimmed off anyway. It will actually fit with the bodywork pretty well. Having this part is a welcome constraint to the design space of the rear of the car. It's a good forcing function to derive the design of the rear structure.
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You guys should take a break from all of this FRCing so we can finally finish the pickup bed.

I am still looking forward to never being allowed to drive it! :-P
 
i am continuously and thoroughly impressed with every step and execution thereof. from design to conception, i appreciate (and am inspired) by every detail. well done, keep up the good work.

also, some people who fashion themselves as career welders hardly hold a candle to a one month hiatus.
 
As I've said before, amazing thread!!

We'd talked a little offline about cam phasor locking the exhaust VVT assemblies (My ECU can't run 4x VVT channels) that suggestion was new to me if I'm honest so I went away and have done some googling.

whilst I understand the concept I have a couple of questions,

I've seen a number of the kits available with pie segments inserts to lock the assembly. Is balancing an issue here or not? Would it be better to fill all the voids to better replicate it being filled with oil? Or will that adversely affect the oil flow path in the journal??

Where would be best to lock the timing?? Is there an accepted figure for the exhaust cam?

Cheers

Liam Mc
 
Is that a TR7 on the lift?

That's my contribution to this thread... soiling all of the photos with the visage of a spectral TR7 forever hovering in the background. Mwa ha ha!

For reals though, it was my grandfather's car. Dad inherited it and couldn't keep it. I found it on craigslist randomly a few years ago and bought it back for $500. It's a 1980 with the red & black tartan interior and no rust. :cool:
 
You guys should take a break from all of this FRCing so we can finally finish the pickup bed.

I am still looking forward to never being allowed to drive it! :-P

Pickup work is imminent! Also looking forward to never letting you drive the FRC :-P

i am continuously and thoroughly impressed with every step and execution thereof. from design to conception, i appreciate (and am inspired) by every detail. well done, keep up the good work.

also, some people who fashion themselves as career welders hardly hold a candle to a one month hiatus.

Thanks Brett, appreciate the kind words.

As I've said before, amazing thread!!

We'd talked a little offline about cam phasor locking the exhaust VVT assemblies (My ECU can't run 4x VVT channels) that suggestion was new to me if I'm honest so I went away and have done some googling.

whilst I understand the concept I have a couple of questions,

I've seen a number of the kits available with pie segments inserts to lock the assembly. Is balancing an issue here or not? Would it be better to fill all the voids to better replicate it being filled with oil? Or will that adversely affect the oil flow path in the journal??

Where would be best to lock the timing?? Is there an accepted figure for the exhaust cam?

Cheers

Liam Mc

Liam,

My half baked and hare-brained scheme is to just drill and tap the rotary piston and machine some tangential slots in the cover plate to convert the hydraulic phaser into an adjustable cam gear. This might be a terrible idea but I frankly haven't tackled the job yet so I might be glossing over some critical point. When it comes time to do the job I'll look into it in more detail.

Is that a TR7 on the lift?

Yes, as Duder mentioned earlier it is purely there to soil the background of every photo.

Simply incredible. I hope you guys will bring this out to some event where it can be appreciated.

Thanks! It's unlikely to get driven to any events but we've talked about bringing it to Davis or something one year just for fun.
 
That's my contribution to this thread... soiling all of the photos with the visage of a spectral TR7 forever hovering in the background. Mwa ha ha!

For reals though, it was my grandfather's car. Dad inherited it and couldn't keep it. I found it on craigslist randomly a few years ago and bought it back for $500. It's a 1980 with the red & black tartan interior and no rust. :cool:

I had a 77 TR7 back in the 80's was a fun car to drive, liked the interior. Mine was BRG with black interior, sold it before it gave me any real problems
 
Liam,

My half baked and hare-brained scheme is to just drill and tap the rotary piston and machine some tangential slots in the cover plate to convert the hydraulic phaser into an adjustable cam gear. This might be a terrible idea but I frankly haven't tackled the job yet so I might be glossing over some critical point. When it comes time to do the job I'll look into it in more detail.

I believe the VVT solenoids work via 0-5v PWM, theoretically would it not be possible to rig up an independant but variable PWM feed to the valve and keep them static electrically?? Would allow you/us to externally vary the exhaust timing without altering anything else?

Any thoughts? Or am I being daft? :)
 
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