LocostUSA.com

Yeah I see the ITRE is in a bit from the upper and lower control arm inner pivots. The rack steering arm (tie rod) looks pretty darn close to being parallel to the lower control arm.

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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

Speaking only from my build with my #'s in the Wishbone program, bump steer is affected by height and Ackermann is affected by fore/aft location of the rack. I ended up with 0 bump steer and 61% Ackermann. I can move my rack fore/aft a total of 3" but it didn't seem to make enough difference to really matter on mine.

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Gavin

My build: http://www.locostusa.com/forums/viewtopic.php?f=35&t=16005

See attached

Getting back to bracing the engine bay, I once experimented with a bolt in X-brace (spider) to stiffen a Locost chassis. It really helped the open engine bay. The roll bar shown had little effect because of its open sides.

After refitting the suspension and reading what yall are saying I'm going to lower the steering rack and probably flip the tie rods to bring everything in line.(or at least closer)

Seeing Bobbers FEA using 1.75" tube for the engine bay brace is a good reminder that itd be easier to just use the same tube as the roll bar. The engine will compromise the design of placing an X on center and/or not having bends in the tubes, but good to know its been tested to a degree.


Ran out of steel for a couple days so made the templates for the sidings. Looking forward to welding in the paneling but I think that's on of the later steps after rear suspension and seatbelts/seats are finalized, so I'm not welding over access to any captive nuts.

Looks like there will be enough angle to save most problems, also finally stitched the 2 upper bars together with 1" welds spaced evenly then staggered on the other side.

I approve of your choice in engine

And you're making great progress!

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Scratch built turbo V8 hot-rod in progress
http://locostusa.com/forums/viewtopic.php?f=18&t=19549

Mounted the coilovers.

Its 4.75mm plate for the mount tabs then on the chassis its welded in with a thinner 2.75" mount plate. The thinner plate exists because there needed to be more area to weld the large shock tabs to, down the line it will also be the mount plate for and engine bay brace.


Flipping the tierods was as an excellent suggestion, Bumpsteer is much better now. The tierod ends will be rebuilt with a heim and through bolt but this is okay until the tools arrive.

Worked on steering column bracing but still not sure what to do with all that real estate, I'm thinking decide after fitting the pedals.

Good progress mate. Just curious, where do you plan to put your intercooler?

Thinking a water to air unit placed above the transmission.

Looks good.

You might consider some additional gussets for those upper coilover mounts. If you could tie into the side of the square tube, right next to the coilover, they would probably be many times more fatigue resistant. As it is, the upward force from the coilover will be constantly trying to peel the bracket off the top of that tube. Either the weld or the top of the tube could eventually fail, and if that happens at the wrong moment it could lead to a crash.

I'd usually argue for over-engineering points like that, where the loads are high and cyclic.

-Graveyard

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Aedifico ergo sum.

Good for you on putting the turbos outboard, though I realize that just sort of happened by itself due to the exhaust manifolds. Putting them out there moves a whole lot of heat out of the engine compartment, frees up space, aids turbo cooling, shortens the downstream exhaust, and puts them on display.

If it was my project, I'd leave out the intercooler and just go low boost of 7 psi or less. Higher power than that will just make expensive smoke, and not necessarily all of that being tire smoke.

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Midlana book: Build this mid-engine Locost!, http://midlana.com/stuff/book/
Kimini book: Designing mid-engine cars using FWD drivetrains
Both available from https://www.lulu.com/

Any way to fabricate a cross tube to marry the 2 top br@cketz?
FWIW my top front coilover br@cketz consist of a single cross tube welded to the frame and cut out at the ends to receive the top coilover mount. I also manage to incorporate the headlight bucket perches in the cross tube. Here's a pic of build #3, the first 2 builds were similar, I believe #2 build cross tube was on top of the frame rails.

_________________
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

There isn't any good way to tie the mounts together though after Omahas suggestion they will be braced into the sides of the tube aswell if space allows. My thoughts were, the steel plate would disperse that energy along the upper structure and give the shock mounts sufficient area to weld to. Perhaps the shock has too much leverage though, a "strut brace" type deal could be welded in, maybe 1" .120 wall would be enough? With some lattice tying it back to the frame to hold it flat.

Going without an intercooler is probably a good idea to start with. Is not like the engine will be particularly stressed and its got a standalone ecu to adjust timing accordingly with iat.(rather then running a stock ecu and praying to stay out of knock)

The engine turbos were put there because I had a spare engine and a bunch of spare turbos, its sort of the optimal setup for a front sump 1uz modifying stock manifolds. The chassis has been built around the motor, the side rails are 12" high in order to clear the exhaust and the wheelbase was determined by how far the front tires needed to be to not rub the turbos at full lock. Its a bit silly, as mounting the turbos further back would've reduced wheelbase and helped COG but this first car is about learning things the hard way.

The idea is to for-go a traditional lotus body and build something with a hardtop and closed wheel. Learning to draw in inkscape has been a struggle so bare with me on the sketchs.

The body is a separate project once the chassis is fully driveable.

Those drawings are great!

A bracket of this style for the coil over would be ideal. And then a "strut brace" connecting the two would help also.