Stuff my dog says; on second thought I'll just build a race car

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Drew the new modified front view right next to the one I did earlier. Lowered the cowl three inches and narrowed the grill by 4 inches. I rolled the top edges more and changed the way the wind screen base is done too. I'm liking this one way better, looks more race car and less 33 Ford Hi Boy.
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Less pleased with the profile now, but I have hope that my objections are only to the drawing and won't be to the finished product. I'm thinking the lack of depth to the 2D drawing and forced low perspective are to blame for the massively slab sided look of the drawing. It's a shame I'm not a better artist.
...if I were a better artist I would have remembered to include the rear axle arm in the profile.
 
Lot's of stuff today, actually car parts not just drawings and theory. To start off though another picture, I added a silhouette of a person roughly my size beside the car for scale to the MS Paint deal from last night. I do think adding that in for scale makes the car look better.
MS paint Antoine.png I named him Antoine and gave him a back story too if anyone is interested.

The plan today was to go in and cut the Wagoneer brackets off the axle tubes and disassemble the transfer case to make sure what I'm planning will work the way I'm thinking it will.
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Plasma cutter, what an amazing tool. Spring mounts were easy to cut off the tubes, then just have to grind/sand the remainder off. The old shock mount is the bit to the right of the obviously torched bit, it proved more stubborn and is flush to the tube so no plasma cutter with it.
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My son sanding the left overs from the spring perches, he doesn't like having his picture taken and I surprised him. I told him Thursday night he was going to go and help me today, but he had an opportunity to take off and spend the night with a friend last night and didn't take it. I was expecting him to find a way out but he actually purposely stayed to help which is fantastic. Spent about six hours outside the house today working and going to lunch together and he never complained about it so maybe he's growing up.
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While he was working on the axle tubes I took the transfer case off the transmission. This bit here proves my theory for the ease of bypassing the transfer case. The main input gear for the transfer case is actually a part of the transmission and uses all it's support bearings so there is no having to create bearing races or anything when making the bypass housing. You can also see the dog gear that locks the input and output shafts together.
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Input side of the transfer case. The transmission and transfer case actually share gear oil with this setup, there is no sealed output shaft from the trans or input shaft from the transfer case. Old school way of doing things, but super effective for me now.
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The output housing and shaft, comes complete with the vent for the transfer case handily enough. Also houses the speedometer driven gear, though I have no use for one of those. Big wide driven gear, the cut shows the dog engagement with the transfer case in 1:1, then the slider would move and cover the wide teeth with it in 2.06:1 low range. The nice thing there is that now unused wide section of teeth is a beautiful place to tack weld the shift collar so that it stays locked in 1:1.
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All that was left was to grab this little bugger and throw the rest of the transfer case away, the shift collar. It was as easy as taking the bottom cover off, pulling the intermediate shaft and intermediate shaft gears out through that hole and then the shift collar will pop out. At least that's how it's supposed to work. I had to use a pry bar.....and then a hammer.......and then a slide hammer to get the intermediate shaft out of the transfer case housing. Jordan ended up having to hold the transfer case because even with the slide hammer shocking the shaft it was still just pulling the whole deal across the bench.
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Did I say simple matter? I mean a simple matter of using the plasma cutter to cut a hole in the case big enough to get the shift collar out because nothing I was doing was causing that intermediate shaft to budge. A soothing dose of fire fixes everything though.
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There is the stuff lined up to the back of the transmission now. Need to cut a flange plate to mate up to the transmission, I ordered a transfer case gasket set this evening to be able to use as a pattern for that. Then we've got a 5 1/2 inch ID piece of thick wall steel tubing I can procure and use for the body of the thing, then just weld another piece of steel to the back side to be able to bolt the output housing to. The wrench in that plan at the moment is the low range gear is bigger than the hole for that output housing, but not needed the gear I should be able to cut it away from the needed part of the collar.

Having got that bit sorted I went and helped Jordan on the axle. We got all the mounts cut off and went to town trying to get some of the rust off. After a bit of that I figured I'd kept the boy away from his friends long enough so I sprayed it down with some phosphoric acid to further attack the rust and we headed on our way.
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I was expecting him to find a way out but he actually purposely stayed to help which is fantastic. Spent about six hours outside the house today working and going to lunch together and he never complained about it so maybe he's growing up.
Enjoy that while it lasts. Maybe he'll learn some along the way. :D
 
Is the roll bar behind the head still an option? It may add a bit of "Cool" factor.

It probably needs to be simply for safety's sake. Also if I ever do try to autocross or anything it may have to be there for whatever technical checks they do. The purist in me says the cars didn't have them back then so this one shouldn't either. At the same time authenticity certainly isn't the name of the game here. Short answer I guess is safety equipment has thus far been an afterthought.
 
Finally got metal ordered today. $440 worth and ended up having to get 11 gauge .120 wall for everything. Disappointed it'll be so heavy, but I do want to build it and gotta work with what I can get.
 
Looks like the 67 I had.
Had a 68 too, but that was a different body.
Edit: thinkin' past the cobwebs... mine was a 66. :doh:
 
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‘66 or ‘67?

'66
It's got a 424 cubic inch hydraulic roller cam engine that did 492HP and 540lb-ft on an engine dyno and a 5 speed Tremec manual transmission. I had a picture of the engine bay but apparently deleted it. It's a Tri-Power induction car too.

On to other things though, I've been doing math.
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Most of that is irrelevant, I just wanted to show everything that was involved in getting the spindle and control arm angles/lengths figured up. I knew about where I wanted to be and knew the height of the wheel and tire and back spacing of the brakes so everything from there was really just trial and error. This page was nearly all error, the drawing isn't really close with the spindle and upper arm so the camber curve was too extreme.
I kept changing numbers and recalculating from there. Find the length of the upper arm then find the lateral deviation at my expected suspension articulation. Then find the distance between the upper and lower ball joint, then plug the lateral deviation number in with the offset of the ball joints and get the resulting angle. Compare that angle with the static angle between the ball joints and that gives me the amount of change in angle at those suspension compression/extension numbers.
The trick obviously is having some sort of target for the numbers in the first place. I had some values tumbling around my head and I honestly couldn't tell you where they came from at this point. What I started out going for was a two and a half degree camber gain with a roughly twelve degree steering axis, and then trying to get the scrub radius as minimal as possible given the limitations imposed by the wheel/tire combination. Interestingly, in an attempt to verify the intelligence of those numbers (guesses) I found a thread where a gentleman promoting himself as an engineer on a race team was going through describing the suspension design process he uses and gave some numbers. It's an amazing amount of information, but a tough read really or at least it is for me. I find myself going back through the posts over and over trying to organize the information in my head.

https://www.physicsforums.com/threads/race-car-suspension-class.326355/

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There's what I ended up with, I ended up having to adjust my numbers based upon what the above link was preaching. Amusingly for me, I didn't have to adjust things all that much. Trying to get a number for roll center right now but wanted to get all this typed out before I call it a night. Looking forward to getting started building.
 
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Each box is 2 inches, so that's probably 1.6-1.7 inches above the pavement. I believe that info suggested 1.5 to 2.5 inches for a stock car on a flat track and less for a formula style car. I'm thinking given the architecture of this it's more analogous to a stock car. Again interesting is that if you add in the 2 degree static camber to the outer ball joint locations you get a scrub radius of 3.5 inches which again is what that guy suggests. He did say that he goes for a 1.4 degree per inch camber curve which is less than what I have, but he also said that with taller section or soft sidewall tires (old bias ply tires for instance) you would need a more aggressive camber curve. His steering axis number was 13 degrees where mine ended up 13.5.

Just to point it out again, I'm not a chassis engineer so I'm more than a little flattered at myself in this context. This could all be an exercise in futility too, just because that guy says he knows what he's talking about doesn't mean he knows anything more than I do. He may be even more full of shit than I am for that matter. There is also the fact that I'm purposely running skinny tires and a lot of unsprung mass with a solid axle in the back, so maximum grip clearly isn't paramount. Really I just see videos of these old race cars sliding through tracks back in the day and think that looks cool I just want my car to do that.:cheers:
 
You know what, it was late and I'm a moron. Each square represents two inches and the intersection point is roughly a square and a half up from the ground. I checked that with my abacus this morning and it turns out that's actually just over 3 inches:doh:

I also forgot to include last night that this other gentleman said the same thing about bump steer that I was thinking about using it to change toe in on turn which is apparently called Ackerman Angle.

Another edit, I was thinking last night after I went to bed that the shock mount will have to move vertically up because the way the Heim joint will have to mount in the control arm is going to interfere with the lower shock mount I had drawn.
 
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Just curious on the tubing... did you give any thought to 4130 chromolly seamless? There's a place here in KC that ships worldwide.
Airparts.

I'd love to go with that if I had the money, even without shipping that would triple the cost of the tubing. When it comes time to make the suspension arms they'll absolutely be made of seamless though. It probably sounds crazy but I'm still hoping to keep costs way down. Also I don't plan on crashing into anything, or even being in a situation where that is a possibility so using the cheaper tubing shouldn't be an issue.
 
I'd love to go with that if I had the money, even without shipping that would triple the cost of the tubing.
Yeah.... always comes down to money. Considering how much stronger seamless 4130 would be, 1.5" by .095 wall would have been overkill. Would have cost almost $500 plus the cost of shipping. :yikes:
But... 73 ft would have been 105 lbs. :D
 
Yeah.... always comes down to money. Considering how much stronger seamless 4130 would be, 1.5" by .095 wall would have been overkill. Would have cost almost $500 plus the cost of shipping. :yikes:
But... 73 ft would have been 105 lbs. :D

I'm still hoping to convince someone of higher means to fund a 60s mid engined formula car at some point and make an aluminum monocoque for it. Gonna save the performance aspirations for that.
 
Moving shit around some more and found another goof up, I had adjusted the bottom of the spindle the wrong way calculating the camber with the one inch extended suspension. The real number is .974 inch positive gain. Maybe I should re do everything just to be safe at this point?

I was looking through all this junk again because the roll center was bothering me and I kinda want it down. I don't have a lot of contact patch and it'd be nice to use it efficiently. Raising the roll center causes shear on the tire instead of loading the tire vertically. Think of a giant imaginary circle centered around the roll center (which also happens to be imaginary). Where that circle intersects the ground ideally would have a tangent perpendicular to the ground, obviously moving the roll center up takes that intersection point farther around the arc so that the tangent starts to noticeably point toward the inside of that other imaginary line of the vertical centerline of the vehicle which is hopefully the lateral center of gravity. Anyway I can lower the roll center by lowering the inside mounting point of the lower control arm. Dropping the control arm mounting a half inch lowers the roll center an inch or so to something real close to 2 inches. That changes the camber arc too though.

With the roll center down an inch that tangent is approximately 2 degrees more vertical. The camber arc drops down from 1.7 degrees per inch to 1.28 degrees per inch. Which one is more important? The other thing to consider is that the further the separation of the roll center from the vertical center of gravity the more the tendency for the body to roll in a turn which in turn loads that outside tire with more force onto that more vertical vector. More body roll also makes a more aggressive camber curve necessary.
So fixes, rotate the upper control arm up in relation to things by moving both the inner and outer anchor points vertically up and lengthening the arm. That increases the scrub radius. It'd also be hard to accomplish with any sort of controlled precision because it probably needs to be moved distances measure in hundredths of an inch. I could just lower the lower arm an inch. That would keep the camber arc and move the roll center down. I'd have to also move the lower arm towards centerline of the vehicle to clear the wheel which is also going to increase scrub radius and decrease the amount of room available for the shocks. Option C is to leave the roll center up and say fuck it.
 
Man, you're pretty deep into this.
Out in the barn (somewhere) I have an old '80s vintage chassis design handbook. It helped me to understand what I needed to do on my Vega. Very involved, complicated stuff. Had to play around with heavy springs and negative caster, to get proper steer feedback with the heavy SBC engine.

Chassis designers, career path stuff...
 
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