1967 Dodge A-100 Hot rod sort of rat rod build thread.

Aluminum tractor exhaust rain cap cast in Waterloo Iowa. Hoping I can find a small one just like it for the wastegate exhaust. We can adjust the decel to give fuel on the computer so it will blow fire out the exhaust. I love this thing. It will flap and bang as the motor is idling is my hope.

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I guess you know the old wheel standers use to inject propane in the exhaust for the fire. DON~~~

 

Well I figured this would be a complete s*** show. So my red car that is a running driving car I did some measurements. I just took a flat surface on the lower rear a arm and at ride height I have a 2° angle. This is for comparison only. The angle means nothing. Then I jacked the back of the car up and that angle became 11°. This is with the rear wheels hanging down. Then I took the new airbag shock and extended it as far as I dare still grabbing enough thread so it won't come apart and with the suspension hanging down I have 5°. As you can see in the video the airbag is hitting the upper arm and I will have to relocate it over and in with a custom block. The factory suspension has a single mono I assume fiberglass of some sort spring with some high pressure gas struts like a shock. Those have a travel of 3 and 9/16. My new airbag shock has a travel of 1 and 3/16. That one and 3/16 is prying on it from when it hits a rubber internal bump stop. So once it hits that bump stop it can go further. Travel will be much shorter compared to a stock car. So from looking at all of this I'm going to have very little down travel when the vehicle comes up in the air. I know each drive shaft will be shorter by roughly two and a half inches. Of course shortening that angle. Drive shaft angle on my red car at ride height was only 2°. The drive shaft shop said their drive shafts I'm going to buy can go up to 30°. So I know I will have less down angle but not quite sure how to figure all of this out. Looking at the video of the corvair ramp side truck at least in one part with the suspension all hanging in there it look like the suspension was almost flat like it should be at ride height. I can't imagine not letting that suspension hang down a little bit for articulation. Anyone got any pointers or suggestions?

 

So I was able to just leave one bolt in. Do some clearancing and rotate the other end around. It is a whole bunch better. If I go a little more the airbag will be in the center of the notch on the upper a arm. This video is at ride height. From here I can always either shorten the shock up or add a block of aluminum for more distance if I want more down travel. Seems like the shocks have a pretty short travel and there is not going to be a lot.

 
53 minutes ago, onanysunday said:

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Leave it in its original location and clearance the upper arms. Can't see that small amount of materials going to weaken it in that location.

 
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richard h said:
Leave it in its original location and clearance the upper arms. Can't see that small amount of materials going to weaken it in that location.
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I thought of that but really did not want to cut into the arm. There is not much there and I think it would certainly weaken it. Especially on this truck with the weight bias possibly being more weight on the rear than on the front of the truck. I went just a little bit further and it is centered pretty close. It really only moves that upper mount in and forward slightly. I can't imagine that changing the geometry very much. It's easy to rotate back and forth and drill additional holes if necessary later on. It will not weaken that casting. It is plenty beefy in there. I almost think I'm going to have to get this thing all built and sitting at ride height and then play with spacing and shimming on the shocks. But at least now I can go up or down. One thing is for sure I want the truck sitting at ride height to be the same as a regular Corvette. Meaning the relationship of the a arms in relationship to the cradle. Those GM engineers are some smart fellas.

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onanysunday said:
I can't imagine that changing the geometry very much
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I wouldn't think that would change geometry at all. Only change amount of load support as angle changes imo. Which is a non issue as air pressure can be increased or decreased for desired ride height.

 
Well this is pretty interesting. With the shock on there and no air in it I set it at ride height and just the random length I have set on the shock right now. Let the wheel travel down and the wheel itself moves down 1 5/16. Travel the wheel all the way up from ride height and bound it into the internal bump stop pretty hard and the travel going up is 2 and 1/8 in. So the total travel of the wheel itself is only 3 and 7/16. As mentioned earlier the shock had 1 3/16 itself. So with a setup like this you really have very little travel. 2 1/8 is certainly not very much travel on the compression side. So I wonder if this thing needs to be set up with almost all of it on the compression side. Meaning I need to shorten the shock up and bring it up closer to the ride height I want. I certainly have to know this dimension to make my wheel wells. But in the front I don't want to make those Wells any taller than I need to. Every little bit in the front is going to make a difference. My corbeau seats are here and I just need to go pick them up from amp performance. When I order them I ended up checking every upgrade box they have for those seats. Lol. 1 in shorter on the base. Fifth crotch slot for the belts. Lumbar support. Heaters. Got to keep Mama happy on that one. And the leather sewn into where your arms go whatever they call that so it wears better than just the cloth. I'm guessing a stock Corvette has at least five or six inches of total travel. This setup will be very different.

 
For now I'm going to give it one inch down travel and 2 and 7/16 up travel. I thought I remember the 1/3 2/3 rule. Not sure if that applies here but plenty close enough for now. I have a lot more bigger fish to fry.

 
So now the big question. Let's say I end up with that 2 and 7/16 wheel travel going up before it hits the internal bump stop. On a real hard hit how much further can that wheel travel? I will probably call the manufacturer of these shocks and see if they can tell me. I have to know this to make my wheel wells high enough. So theoretically if I let the air out of the bags and I have a five and a half inch ride height the car will be sitting at around 3 in. And maybe the weight of the truck will compress into the bump stops a little bit more and let it go further. :ng:

 
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Well the mill was the perfect fixture to clamp it all back down. I was able to tap it around and get everything dead nuts straight. Ended up shortening the cradle just under 6 in. One of our better TIG machines in the shop was close and we were able to get it over to the mill.

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Oh yeah. I put big champers in it. All filled in. Now I can start cutting and grinding some more on the bed. Inside the inside on the unibody frame rails is 33 and 1/4 in. Width of where my 2x4 box for the frame and the mounts will be 26 wide. So that leaves a 3 and 5/8 Gap between the new frame rail and the old unibody rail. Not quite sure how I'm going to fill all that in. Unless I angle the rails over so they run parallel with each other. Then gusset around the cradle area

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I was going to do a bunch of bracing before I cut out the rear portion of the unibody. Figured those bed  sides aren't going to give much and it seems to be staying put. I still did support the bottom corners though. I've been looking for a long time for another rear tire and ready to give up. Need to just find any old tire that will go on there for now. Certainly did not want to spend $600 a piece and then have them sit for a couple years while I build this. My front brackets from Rick Dobbertin are on their way. Now I will have no excuses to get this thing built. LOL

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I have decent vision out of the glass but clearance between my head and the roof is maybe 3 in. I think I might be able to drop the seats an inch. This thing will probably end up with a Gurney bubble on my side which is fine.

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Starting to try to figure out how far to tuck the front tires underneath so I have full steering lock to lock. Took my red car and used a square to do some layout. Interesting how the tire moves forward slightly as it turns. The front of the tire as it turns outward looks to be the dimension I have to worry about the most. Of course the inward dimension will be easy to build tubs because the steering will be working at that point.

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