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Ho, ho!!!! I beg to differ!
I've had many arguments with myself whilst building 7's. Only consoling factor is one of myselves always wins.

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Perry

'If man built it, man can fix it'
"No one ever told me I couldn't do it."
"If you can't build it safe, don't build it."

Perry's Locost Super Che7enette Build
Perry's TBird Based 5.0L Super 7 L.S.O
Perry's S10 Super 7 The 3rd
Perry's 4th Build The Topolino 500 (Little Mouse) Altered
Perry's 5th Build the Super Slant 6 Super 7
Perry's Final Build the 1929 Mercedes Gazelle

So it has been a while as I got distracted with my daily driver Dajiban build and getting it ready for a family road trip to Knox Mountain Hill Climb. I also put a new engine in my RX8 so that is working again.

As for the Seven, I've done a bit though as I now have a self supported rolling chassis, nothing underneith. I still have a ton to do to finish up the front suspension, today however was good enough for it's first test and it works!

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Convincing yourself you can do it is one thing, convincing your wife it is a good idea is another. Glad I have a great wife!

1999 Dajiban build
Autcross car currently 2009 Mazda RX8 R3.

Build is a plus 4" width, 13B Renesis. Wish me luck.

Update with more detailed shot of my suspension, and I now have my steering column mounted.

Question, I have not found info on this but it was mentioned to me, any one know the legality of extending a steering shaft, my plan was to use DOM tubing and have the two cut ends of the shaft inserted about an inch on bother ends(near press fit) then weld. Someone told me steering shafts can not be welded?

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Convincing yourself you can do it is one thing, convincing your wife it is a good idea is another. Glad I have a great wife!

1999 Dajiban build
Autcross car currently 2009 Mazda RX8 R3.

Build is a plus 4" width, 13B Renesis. Wish me luck.

The adapter needs to be locked to prevent rotation with another bolt or pinning. A rocker setup would solve the problem.

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Miata UBJ: ES-2074R('70s maz pickup)
Ford IFS viewtopic.php?f=5&t=13225&p=134742
Simple Spring select viewtopic.php?f=5&t=11815
LxWxHt
360LA 442E: 134.5x46x15
Lotus7:115x39x7.25
Tiger Avon:114x40x13.3-12.6
Champion/Book:114x42x11
Gibbs/Haynes:122x42x14
VoDou:113x44x14
McSorley 442:122x46x14
Collins 241:127x46x12

I originally thought so too, but the bolts being in opposite axis seems to be fine, and makes the adapter act like a single pivot. The force on the lower mount I assumed would also be fine as the car will actually weigh less then half of an RX8. Please correct me if I'm wrong.

_________________
Convincing yourself you can do it is one thing, convincing your wife it is a good idea is another. Glad I have a great wife!

1999 Dajiban build
Autcross car currently 2009 Mazda RX8 R3.

Build is a plus 4" width, 13B Renesis. Wish me luck.

My concern is the nut on the lca loosening from the adapter rotating a small degree back and forth with suspension movement. The lca is moving around on the bushings dynamically under the various loads and there isn’t anything to keep the lca stud from rotating a little relative to the adapter. I’d be cautious about making the nut super tight due to the casting. If the adapter had a spherical on the end would fix that but then it could flop back and forth in the coilover clevis. Definitely easier to go with pushrod at this point but I might be over-estimating the force and arm acting on the adapter, so it may take a lot longer to loosen up. If you don’t want to go with pushrod, use locking fasteners to hold the adapter on the lca and check the torque regularly. Regular nuts could drop the suspension quickly after initial loosening from rotation.

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Miata UBJ: ES-2074R('70s maz pickup)
Ford IFS viewtopic.php?f=5&t=13225&p=134742
Simple Spring select viewtopic.php?f=5&t=11815
LxWxHt
360LA 442E: 134.5x46x15
Lotus7:115x39x7.25
Tiger Avon:114x40x13.3-12.6
Champion/Book:114x42x11
Gibbs/Haynes:122x42x14
VoDou:113x44x14
McSorley 442:122x46x14
Collins 241:127x46x12

I did not consider the dynamic movement of the bushings. Definitely something to consider. I may do locking fasteners and check it all regularly, the factory actually loctites the lower shock bolt, on an RX8. I did not want to do push rods as I need the room of where they would go for a fuel tank these engines are thirsty little buggers and I'd like a range of more then 50km. I will consider and revisit that option under your suggestion. (I always like the adjustability of pushrods, hence my front setup )

_________________
Convincing yourself you can do it is one thing, convincing your wife it is a good idea is another. Glad I have a great wife!

1999 Dajiban build
Autcross car currently 2009 Mazda RX8 R3.

Build is a plus 4" width, 13B Renesis. Wish me luck.

So, I have been quite for a while, but it does not mean progress is not getting done.

I have got my firewalls done, clutch a brake Master cylinder's mounted, plumbed all brake and clutch lines, mounted my proportioning valve, made clutch and brake pedals, mounted the RX8 throttle pedal, made all parking brake cable mounts and placed the hand brake (all functions great). I am debating what to tackle next.

Engine cooling - thinking a EG civic half rad, upgraded to a double or triple core aluminum unit (I've seen 13b builds with this). I have 2 RX8 oil coolers to also mount. I was thinking of having the oil coolers right up front and sliding the rad in between the front crossmember and the engine. Was wondering if I should do the opposite though?

Drive shaft - this is a big one, the RX8 comes with a CF drive shaft, I like the safety factor of this because it spins just 3-4 inches from my hips. CF is fairly non destructtive if it fails and a metal one becomes a massive weapon of destruction. Does anyone have experience shortening a CF driveshaft? Stock is 42.5 inches and I need it just 19" between ujoints. I figure it may be worth exploring as the rotary is a low torque motor and the car will weigh an estimated 12-1300lbs (2000lb less then an RX8). This is about as low force as any driveshaft will see is it not? What would be a reasonable way to go about this, I'm open to ideas?

The cost of getting a custom drive shaft has scared me a bit. I have taken this (low)cost thing very seriously and between selling off parts and things I am probably just $5-600CAD (not including shop supplies like welding wire, gas, grinder discs ect.) into this and a drive shaft will more then double that if I just buy one.

_________________
Convincing yourself you can do it is one thing, convincing your wife it is a good idea is another. Glad I have a great wife!

1999 Dajiban build
Autcross car currently 2009 Mazda RX8 R3.

Build is a plus 4" width, 13B Renesis. Wish me luck.

I would think you could very, very carefully cut it near the diff end, leaving a few inches for a mating center plug.
Cut your section out, then machine a plug that could be epoxied in to join the ends. Maybe rivet to the plug through the walls?
Surface prep, wrap with epoxy soaked thread, have it balanced, and then hope it all works.

If you're lucky, then the u-joint end is already an "epoxy in place" style, and the machined join plug wouldn't be needed.

They're cheap enough on the used market that I would try it, most people toss them when they go V8 conversion.

I've never done it, so there are a few dozen assumptions in there.

I had a similar idea for sure. It looks like it may be an epoxy in place u joint but I'm not 100% sure how to know without diving in to cut it up. I'm wondering if I should cut it in the middle to have a look inside as well and get a better idea. This would still leave enough shaft left that if I can get the factory ujoints out I can just attach it to the one half that was left in place with the slip yoke.

_________________
Convincing yourself you can do it is one thing, convincing your wife it is a good idea is another. Glad I have a great wife!

1999 Dajiban build
Autcross car currently 2009 Mazda RX8 R3.

Build is a plus 4" width, 13B Renesis. Wish me luck.

As I built the lower A arms myself, these things are incredibly light, and my DS is just over two feet, I don't think my DS is going to fail. So with that in mind, I took my steel unit to a shop to shorten, weld, and balance. Think he charged me just over $200.00. If it does fail, I've got the transmission tunnel tubes and steel skin it would have to go though first before it get to my legs.

Your car and comfort level obviously, but a failing DS is going to be the least of my worries while driving.

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Trochu Motor League

Okay, I have not cut up my drive shaft yet, but found pictures of a broken one, and one taken apart. It really looks possible, I just need to find a bonding epoxy, that can handle me plugging the one end back in. I'm trying to make sure I can do this before I start cutting stuff up. Any further input is appreciated as I am convinced it has to be harder then this is seeming (it can't be just a cut and glue? Then get balanced. Or can it?)

Edit after some reading, could this be true? I have found it is rumored to be a press fit, no adhesive?

Oh yeah, Also on the cooling question? Oil coolers in front or rad in front? What would be more effective?

_________________
Convincing yourself you can do it is one thing, convincing your wife it is a good idea is another. Glad I have a great wife!

1999 Dajiban build
Autcross car currently 2009 Mazda RX8 R3.

Build is a plus 4" width, 13B Renesis. Wish me luck.

I figured it would be splined. Yes, it could be just a one-shot press fit so make sure the yokes are in phase. I'd probably seal the end so no water can get in and corrode the steel or become a dynamic balancer and add a paint stripe/witness mark across the tube and yoke to check down the road for any slippage.

I'd also mod the rear, not the front incase it doesn't work out. I'd rather have a problem with the rear rather than have my car pole vault if no safety hoop.

_________________
Miata UBJ: ES-2074R('70s maz pickup)
Ford IFS viewtopic.php?f=5&t=13225&p=134742
Simple Spring select viewtopic.php?f=5&t=11815
LxWxHt
360LA 442E: 134.5x46x15
Lotus7:115x39x7.25
Tiger Avon:114x40x13.3-12.6
Champion/Book:114x42x11
Gibbs/Haynes:122x42x14
VoDou:113x44x14
McSorley 442:122x46x14
Collins 241:127x46x12

Thanks a ton for the safety tip on doing the rear, (that is what I planned anyways but good to have a reason) also my tunnel is closed in on the bottom so it would not pole vault no matter what. My access point is from the driver's side as this is what I needed to do to fit my shortened PPF that I have maintained. Yep I kept the PPF so my entire drive unit (engine, trans, and diff) bolt together as one solid unit just as it did in an RX8, Miata and 3rd gen RX7.

_________________
Convincing yourself you can do it is one thing, convincing your wife it is a good idea is another. Glad I have a great wife!

1999 Dajiban build
Autcross car currently 2009 Mazda RX8 R3.

Build is a plus 4" width, 13B Renesis. Wish me luck.

I have confirmed it is press fit... I have carefully by hand cut down the drive shaft so I just have to see if I can press it in.

Sand down the rough edge
Make sure it is lined up
Press in
Hope it all works

This could turn into the easiest driveshaft shorten ever, or end in epic disaster.

_________________
Convincing yourself you can do it is one thing, convincing your wife it is a good idea is another. Glad I have a great wife!

1999 Dajiban build
Autcross car currently 2009 Mazda RX8 R3.

Build is a plus 4" width, 13B Renesis. Wish me luck.