Well, the midlana book might be a good way to spend a couple bucks. He's on the forum here but I can't think of his username right now.
I think he lives on the west coast though.
Well, the midlana book might be a good way to spend a couple bucks. He's on the forum here but I can't think of his username right now.
I think he lives on the west coast though.
Frame horns are heavy. Fabricated strut mounts don't have to be. You are being forced to save weight. Embrace it.
Just a few questions that I'm sure you've already asked yourself. You choose the MR2 as a donor because you saw the way they went through the autocross at this years Challenge right? I assume so because I watched them and felt my pants get tight. How are you going to keep the MR2 suspension with your tube frame? Can you drop the subframes out and then just connect them with tubes? Are you able to keep everything in line? For a real world example I've been thinking of using the 350z front suspension on a tube frame type build. Looking at it the lower A arm connects to the 350z crossmember. That's cool but the upper A arm connects to the unibody as does the top shock mount. Top shock mount is solvable because really I can play close enough and get it in a general area. The uppper A arm mounts not so much Now I'm looking at binding and all kinds of weird suspension movements if I'm off just a 1/16 of an inch. So I've spent a lot of thought on how to make a jig to locate everything off the car hard mounts then build a custom K member type thing to locate them all back in the proper relationship. Now after all that thought think of the rear subframe of the 350z. Four bolts and the top of the shocks and it drops out keeping all the A arms intact. Yeah I'll have to get the shocks somewhat close enough but not that hard to do. All I have to do is make sure my four bolts are square and level to the frame I'm building. Sorry for the long response but these are things to consider. BTW ... something you know more about, the Miata front A arms look to be easier to adapt than the 350z.
In reply to Stampie :
Good thoughts.
No. I did not choose the MR2 because of this year’s autocross. I chose the MR2 years ago because it appeared it would fit, and because they are very nimble.
The MR2 does not have subframes- suspension pickup points are directly attached to the unibody. So yes, it would be a great deal of effort to replicate. The Avalon uses subframes.
If I chose to go tube frame, the MR2 would no longer be relevant. But a tube frame is much more than I want to build.
This is a thought exercise.
In reply to SVreX :
Iirc you still have the Europa front suspension. Have you thought of just building a rear subframe with the Toyota stuff?
In reply to Stampie :
That’s a good thought.
In reply to Stampie :
The problem is it takes me back to my original conflict with the Europa chassis. There is no floorpan, and the spine construction doesn’t give anything to attach a rollover structure to.
It would, however, give me more to start with than building a tube frame from scratch.
Assuming that this is the area of concern:
And keeping in mind this is a 2020 project, not 2023 or beyond, scope creep must be contained.
I would consider adding inner fender braces similar to Frog Arms and then knock that corner back as needed to clear the body. Plate the area back over to re-close any previously boxed structure, and call it good.
https://fab9tuning.com/boss-frog-frog-arms-chassis-braces/
In reply to gumby :
Yup. That’s it.
Thats the thought process in my head. Knock off those corners, or abandon the MR2
Chop it till it ckears, take pictures and post. Then we'll see if mr2 needs abandoning or not. Its not like the mr2 has any value at this point if you ruin it.
Im thinking a simple plate over the chopped sections will be fine, but seeing it is another thing.
In reply to Dusterbd13-michael :
I stopped worrying about ruining it a long time ago!! Haha!
Woody said:In reply to SVreX :
I think Dr. Hess May have the recipe for a tube frame.
This needs repeated.
btw, a solution to the roll cage problem is to make a wide version of that where the driver sits there just like a formula car. The body is just an shell, just as if it were mounted over the mr2.
It will be a pain to get in and out, but at least the roll bar would firmly mounted to the chassis.
edit- one more thing to add, iirc, the chassis is fairly basic in terms of cutting and welding. Very much on par with dropping a body onto a different car.
Dusterbd13-michael said:Chop it till it ckears, take pictures and post....Its not like the mr2 has any value at this point if you ruin it.
Strut tower bracing can be added in the frunk area if necessary as well.
Get crackin' 
Direct quote from you:
I'm only a mediocre builder. I've never built an engine, am pretty good with suspension, body, detailing and finishing, and minor fab work
make the mr2 work. Don't go down the tube chassis rabbit hole because you'll be calling me in a couple years to come get the free europa and I don't need it.
chop chop chop the mr2 stuff till it clears then reinforce as needed. Especially in a shipping container, you're not making a frame table in there that you can move around enough to weld anything properly
May or may not be anything of use to be found in this thread
http://forum.retro-rides.org/thread/186907/attempting-build-worlds-quickest-legal
On the Molvo, I just trimmed the Miata chassis until it fit inside of the Volvo sills. Since I had the same support concerns you have at the corner of the engine compartment to firewall. I created a tube structure that runs all along the sills and into the front chassis. Kinda like a frog leg.
On a fiberglass car like the Lotus, this adds side intrusion protection and a place to hang a roll-bar if that is in the cards.
Pete
Patrick said:chop chop chop the mr2 stuff till it clears then reinforce as needed. Especially in a shipping container, you're not making a frame table in there that you can move around enough to weld anything properly
I'm with Patrick and Michael on this one. Chop it till it fits, then reinforce.
If I were closer I would offer welding, but there's a bit of distance there. I also wouldn't be too afraid of welding, I'm self taught, and I think starting to get the hang of it. The easiest way to learn is practice. Just do it. MIG you just pull the trigger and go. Only 2 settings to adjust on the machine, and listen for the bacon sounds. Just make sure you get a decent auto-darkening helmet. I started with a super cheap one and it was terrible. Got a ~$45 one from Eastwood and it improved things dramatically.
Building a new chassis can be a bit of an undertaking, but it would allow you build a cage around where the soft squishy parts reside. How bad is the stock chassis of the Europa? You could scab on a roll cage, then gut the body to drop over it, sort of along the lines of what Palatov is doing.
Building my chassis didn't take too long to get a roller, but doing all the fiddly bits did take some time:
In reply to RoddyMac17 :
Do you have any more details/ pics of your build?
The picture you just posted is exactly the path I was just considering. Chop the original Europa chassis behind the tunnel, and build a new back half.
SVreX said:In reply to Stampie :
The problem is it takes me back to my original conflict with the Europa chassis. There is no floorpan, and the spine construction doesn’t give anything to attach a rollover structure to.
It would, however, give me more to start with than building a tube frame from scratch.
I can't find it now but when discussing my Lotus chassis with Tom he sent me a picture of what he thought would work. Basically a floor tube going from the center backbone in front of the drivers feet then along the side and then going behind the driver continuing to the backbone again. It may be in my emails. I'll look this afternoon.
In reply to SVreX :
The build log is here: Europa Resto-mod but some of the picture links are broken. Other pictures can be found here IMGBB Photos
In reply to RoddyMac17 :
Hang on...
Your build thread shows full tube frame. The photo you posted in this thread is only a rear half tube.
The tube frame was sheeted in aluminium to allow the use of closed cell foam between the chassis and body.
Here's a concept of caging a Europa chassis (though shown is a 47 chassis): 
You could build the cage and cut the rear chassis legs off, then build a new tube frame section that integrates with the roll cage to accept all the MR2 suspension points. But it would mean a lot of measuring and welding. And, to attached the cage to the chassis, I would weld plates on the ends of the roll cage tubing where it would contact the stock chassis and then weld the plates to the Lotus chassis to spread the load (the stock chassis started off as 16 ga steel).
I'm going to get back on CAD this weekend. Let me see if I can throw something together for a relatively simple back half for a transverse drivetrain to scab to the front of a lotus chassis that also has roll bar/cage consideration. I think you could do it relatively easy..
In reply to nocones :
That would be awesome!
The MR2 isn’t dead yet, but I’m realizing this is a good moment to consider carefully the hole I dig myself into.
I want the car the have a life after the Challenge. A butchered MR2 chassis might limit that. Plus, there are other considerations. The MR2 chassis brings with it a lot of other stuff that adds complications... wiring harness, existing suspension locations, fitting to a chassis it doesn’t belong on, tire wells, lines remaining for emissions, fuel tank, cooling tubing... the list goes on an on.
Most of those things are small problems. But lots of them, which equals a lot of time, and robs the project of simplicity.
Re-using the Lotus chassis would take me back to simple, gain me a finished front end. I’d just have to consider a back half frame that included mounts for the 2GR motor, trans, subframe, and rollover protection.
Yes, the welding is a skill I don’t yet have. But the work involved may actually be less, and the finished product may be significantly cleaner.
I don’t want a chopped up abortion that is only useful to impress a few people at the Challenge. I want to build a resto-mod. If it meant it took an extra year to build, so be it.
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