LocostUSA.com

Not a programmer, but still hoping I can get some use out of the book. The second looked like it would be useful given the frame pictured on the cover. But yeah, I know I already have fixed dimensions in the spindle geometry, but I'm confident I can compromise around any issues that come up. I mean so far, I'm pretty happy with it.


Cold day here, but I managed to finish up the control arms tonight:

Few minor things arrived.. New front hubs, and pads/rotors all around.


Been fiddling quite a bit with the suspension and steering geometry. Found a good place to get a custom rack built, so I have been working on the steering geometry too. Not quite ready to start welding yet, but so far the numbers are encouraging. 5" of rack travel will get me a very nice turning circle (still need to decide on a steering ratio though). Getting 4 degrees of caster with plenty of adjustment plus/minus. With 1deg of static camber, I am getting the outside to be at 0* in a hard turn, and the inside wheel has 1-2* of -ve camber. I think I can live with that. Added a bit of anti-dive, but might put a little more. I also had to put the rack slightly back of the centerline between steering pickups on the spindles, but that has a nice side bonus of, amazingly, basically perfect ackerman. And essentially no bump steer. So if anyone asks, I meant to do that......


Next step is to decide on wheel rates and spec out some shocks!

As light as your Seven will be you could easily reduce the anti-dive by half. Heavy sedans with soft springs and a heavy motor run that much anti-dive. Your typical Seven is sprang pretty stiff.
I'm running about 1.2* I would also kick up the caster, unless this is a track only car.
Most Seven's are set up with about 5/8 to 3/4" frame rake, which effectively reduces the caster.
Dave W

Hm, interesting. The book I linked above suggested the anti-dive angles should cross at the center of gravity. I thought that was excessive.. will do more research.

It will be a track-only car but I'm sure I can get more caster if need be. What's the reason for the frame rake? I hadn't factored that in at all.

The frame rake is typically used to as a way of adjusting wt transfer on the rear.
Being a track car, I would suggest that you look at running RU1&2 tubes horizontally Vs at an angle. That way you can mount the pandard rod lower. i.e. a lower roll center.
Also for a track car you may want to look at increasing your ackermann.
Dave W

Good advice, thanks. RUs are already welded in and to be honest I really like the look, so I will leave it as one of the few concessions to style.

Had a rough day at work today so decided to test fit my axle. Strongarmed the thing in there on my own. So far so good, I think. The trailing arms will be level with the car at ride height, I just didn't have any wood the correct thickness.




You can also see how I figured out the panhard rod. The chassis-side mount will be on the opposite frame rail. Hopefully that LCA bolt stud doesn't hit the frame at full droop. Don't think it will, but need to check. If it does, I will put a hole through the panhard bracket so I can feed the bolt in through that side. It's fully boxed so I'd have no concerns. Also, I am just using standard nuts for test fits, don't want to wear out the nylocks.




Really hoping to start on the front suspension soon. Though I may focus on getting the engine mounted first, because then I can get a driveshaft and build a tunnel for it.

I suppose I should update this again. I have been working hard over the summer and even harder now that it's winter again. I decided to paint the chassis now because I won't be able to sandblast it later on in the winter, and most of the major welding was done. Where I need to add a small bracket here and there, it's easy enough to grind the paint away, weld, and touch it up later.

I kept the wheels and tires from my RX8 for the purposes of test fitting. They are 245/45 on 17x8 SN95 Mustang wheels. Not exactly the ideal size, but for the purposes of test fits and perhaps initial road testing, they should be okay.

I am currently working on the pedal box and mounting the fluid reservoirs. Once that's done, I will likely plumb in the brake lines, followed by the fuel lines, leaving electrical to the end.

https://drive.google.com/file/d/1n22YY9 ... sp=sharing

Ah, I see the attachments are displayed in the reverse order of uploading, haha.

Could not see the vid; "invalid parameters".

What dampers are you using? I'm always looking for cheaper alternative adjustable coilovers.

The top of the dampers should mount as far out as practical (i.e. effective angle). A low effective angle requires higher than necessary damping adjustment and stiffer/heavier spring rates to compensate. Yours appear to be about 50% effective at that angle.

Ideally, the rear damper upper mount should be forward of the lower mount to prevent a falling rate, where the suspension gets softer as it compresses (axle moves forward in bump).

A motorcycle engine may not be allowed in your state to title for public road use. Some have complained here that they could not get their bec on the road when they never asked about registration. It varies.

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Miata UBJ: ES-2074R('70s maz pickup)
Ford IFS viewtopic.php?f=5&t=13225&p=134742
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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

Oh boy, I have been terrible with updating this thread. I have been focused on finishing it up in time to enjoy as much of the summer (and local autox events) as possible. I'm pleased to say, I am booked in for the safety inspection later this week! Fingers crossed everything goes well.

https://youtu.be/1ncUqjvzq3c

I got a temporary 'in transit' permit that allowed me to take it out for a spin to try and shake out any issues before the inspection. I had to go back and spend a bit more time on my initial wheel alignment, but I got everything pretty close in the end. I'm very happy with the steering feel and the suspension feel, so I think I managed to get pretty close to the mark with my suspension and steering geometry, spring rates, etc. One thing I did not expect is the level of engine braking from the bike engine. Apparently it's normal for bike engines to have a good bit of engine braking, but I was not expecting to be able to rely almost entirely on that while driving (gently) on the road. I also need to get used to the feel of the pedals, the clutch friction point and so on. I feel as though I am at a bit of a disadvantage having no experience with motorcycles, but I'm sure I will catch on eventually. Already loving the feel of the sequential gearbox!

Hey ZiG
Where you at? I'm thinking Southern Alberta? Are you on the Alberta 7's list?

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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

He's gotta be hey. I doubt people are driving to far to drop a grand on a Haler frame.

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Trochu Motor League

Yeah I'm in Calgary, and yes I am on the list.

I got it registered! I was careful to read the rulebook as I went, so thankfully that paid off and it was found to be compliant. Alberta requires a windshield wiper, sprayer and defogger. The sprayer was easy enough, and I took a page out of Jack's book for the wiper. It clips onto the upper frame and is fully automatic, as is required. For the defroster, I bought a very cheap 12v heater. It and the wiper can be removed and placed in a bag until needed.

I had to sew my own boot cover, and although I have never been accused of knowing my way around a sewing machine, I am happy with how it turned out.

I also needed to rebuild the rear end when some metal shavings got in there. My own dumb fault, and a long story. I took the opportunity to press in new bearing races (something I'd not done the first time around) and installed a clutch type LSD.

After getting the car registered, I promptly went to an autocross event the next day. It was a ton of fun, but I was way over the noise limit and was not able to run in the second half of the day. 95.9 decibels and the exhaust was on the opposite side of the car from the meter! I have ordered a Car Chemistry muffler insert, fingers crossed it helps. The drone is almost ear-splitting at highway speeds, too.. But, beyond that, the car did great. I did resist the urge to push it hard, and I can tell I need to reduce my tire pressure from the 30psi I started at, but it feels like it's going to be fast.

I also went to a weigh scale today. 290kg (638lb) front, 370kg (814lb) rear, 660kg (1450lb) combined. That was with a quarter tank of fuel, myself, and some tools on board. After subtracting my and my tools weight (I won't say how much was me vs the tools), the car comes out to 1250 lbs! Very pleased with that number. For the purposes of useless bragging rights, that puts me just under a Hellcat in terms of lbs/hp with no driver, haha.

Here's a video of the third and final run at autox. Forgive the terrible start, it's a brand new clutch and I am very much not used to it. https://youtu.be/u_0MxUgB5jg

Nice video. I'm impressed with your job on the boot cover. It looks completely professional.

Cheers,

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Damn! That front slip angle is way too large and the Ackerman is just a muddle.

Build Log: viewtopic.php?f=35&t=5886