818 Chassis

[jbs72697]

I’ll be at the point soon when I actually will be starting to work on my 818S starting with the underbelly aluminum. I’m going to try to tip the chassis on its side as suggested in the manual. My concern is if the door mounts are strong enough to support the weight or should I block around it so it rests on the main chassis

[TheHelixx]

Hopefully this gives you confidence..

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Maybe lay down cardboard so you don’t scratch anything.

[Dave 53]

I suggest knowing exactly how you will mount your seats and seat belts before installing the aluminum. I would have welded in some tabs first if I had a do over.

[jbs72697]

Yes that’s just the kind of advice I was hoping for. Thank you!

[jbs72697]

Thank you.
What were the issues you ran into?

[idf]

For what it's worth, I drilled and riveted all my panels lying on my back. I don't think the manual mentioned lying the chassis on its side when I built mine, and it never occurred to me. If you are unsure about possible frame modifications you can always cleco the panels now and rivet later. I disassembled my chassis dolly but still have the casters if you can use them. Also have a pneumatic riveter if you are interested.

[Dave 53]

Drill the rivet holes while you have an opportunity for easy access but hold off on riveting until you got the seats and belts figured out. You may just end up drilling the X brace, but nice to keep the option open to weld in some tabs later in the build.

My car started out with OEM donor car seats. They lined up well to drill the X brace for mounting and the belt mounts are part of the seat. But any aftermarket seats will have different bolt patterns and no seat belt mount. I replaced the donor car seats with OMP Raid 2 seats (very comfortable, looks good, fits in the car perfectly, but just okay on track). I fabricated bolt in seat and belt mounts, but a more elegant solution would have been to weld in mounting tabs. Super easy to do without the floor in place, pretty much impossible with the floor in place. I thought about removing the floor to weld, but my floor is glued in and breaking a glue seal is difficult.

Along the same lines, I suggest drilling the fire wall rivet holes when it's easy to do so, but don't rivet until you've passed all your go kart test. It's easy enough to drill out rivets, but after the 4th time, I switched to bolts. At a later date, you may need to access the fuel tank (pump, sender, gaskets, hoses) or timing belt. Don't glue it in! I spent a full day with a blow torch and a 3 foot chisel I made breaking the glue seal from the previous owner.

[jbs72697]

A pneumatic riveter, that’d be great and really appreciated!

[jbs72697]

Drill the rivet holes while you have an opportunity for easy access but hold off on riveting until you got the seats and belts figured out. You may just end up drilling the X brace, but nice to keep the option open to weld in some tabs later in the build.

My car started out with OEM donor car seats. They lined up well to drill the X brace for mounting and the belt mounts are part of the seat. But any aftermarket seats will have different bolt patterns and no seat belt mount. I replaced the donor car seats with OMP Raid 2 seats (very comfortable, looks good, fits in the car perfectly, but just okay on track). I fabricated bolt in seat and belt mounts, but a more elegant solution would have been to weld in mounting tabs. Super easy to do without the floor in place, pretty much impossible with the floor in place. I thought about removing the floor to weld, but my floor is glued in and breaking a glue seal is difficult.

Along the same lines, I suggest drilling the fire wall rivet holes when it's easy to do so, but don't rivet until you've passed all your go kart test. It's easy enough to drill out rivets, but after the 4th time, I switched to bolts. At a later date, you may need to access the fuel tank (pump, sender, gaskets, hoses) or timing belt. Don't glue it in! I spent a full day with a blow torch and a 3 foot chisel I made breaking the glue seal from the previous owner.
That is a good point to think ahead to future access of the components, engine, etc
Thank you. I’m looking forward to getting started

[TheHelixx]

I had to get back at the sending units after completion because discovered the secondary leaked near the barb. I had a custom dash that needed to come out if I was to remove the center console and get the firewall out. I ended up cutting an access hatch to get to them right through the carpet and made a cover to close it back up. If I had a second swing at it, I would have cut the firewall at the top of the tank and made it 2 pieces. That way I could easily get to the front of the engine and or the sender units. This way I just need to take out the seats, which is tough enough with a coupe.

For my seats I just made a frame that mated to the x brace of the chassis and the mount holes of my seat. While I was at it I welded tabs for the factory belts as well as a 5 point harness. There’s 2 studs welded to the rear of the mount through the floor. Then 2 5/16 bolts through the front. When you unbolt it from underneath, the seats come out with the mount and belts attached.