The GRM Free Lotus Europa - 2GR V6 Swap $2000 Challenge Car

In reply to nocones :

I am interested too! I had done a bit of reading on the Deltawing for weight distribution (72% rear!), but didn't get deep enough for the other details. I hadn't considered the Stratos. The Europa wheelbase is only 6" longer (92" vs 86") so it's a valid comparison, with similar weight too. The Stratos was 63% to 56% rear depending on the website. When I added the rear toe link, I made it longer so it slightly toes in under compression, which should understeer instead of oversteer.

Right now the whole chassis will balance on my jack if I lift under the subframe's front tube. The weight seems pretty centered left-to-right. The body's CG is much further forward based on furniture dolly experiments, somewhere around the driver's thighs. All weight I add from here on out, except maybe battery and exhaust, should help move the CG forward. 

the stratos has strut rear suspension, so you should be slightly ahead on the geometry front

Warning: big wordy and technical-babble post ahead. 

So that twisted frame thing. Here's what I'm talking about. Even though both sides have similar weigh, the passenger side is sitting about 1/2" lower and therefore the upper control arm angles are very different. This amounts to about 1.1 deg of frame tilt, as measured at the UCA frame pivot point, and 0.9 deg at the foward part of the tubular structure. Disclaimer: all measurements and math in this post have been executed with very little precision as evidenced by my Pittsburgh brand straight edges.

The front of the frame is level. I also measured heights of the front UCA pivots to the ground, and they are within 1/16"

If I shim the passenger side up about 1/2", I can get the rear frame level. This should inherently make the front unlevel now.

At this point I started marking the frame for cuts. But then I realized the front frame width is much narrower than the rear, so actual change in heights of the front control arms is much smaller. Perhaps I can exploit this?

I built in some ride-height adjustment for the rear: coilover preload, coilover mount shims, and pushrod length. I took one shim from driver side and added it to passenger side. That's a total of about 1/4" correction.

Then I unlocked the passenger pushrod and extended it a few threads. Another roughly 1/4" of correction.

Now the UCA angles are pretty darn close!

Eyeball test also says the suspension is symmetric now.

I adjusted my VSUSP model ride height and static roll angle until I matched these measured angles. I think I can live with this.

Then I measured the front frame angle. About 0.4 deg. But more importantly, the UCA and LCA mounting point heights to ground are still within 1/8" of each other side-to-side. And the front has much less aggressive camber curve, and I don't want to cut anymore, so let's call this fixed. Of course, all of this will change slightly as I add weight, but this is a good baseline to build on.

Now I was curious about toe, and how that will change with weight and travel. I strapped 4ft levels to the tires and measured the distance front and rear. I can just barely snake the tape measure through the tube frame up front. The front-rear difference, scaled down to tire diameter, should be my total toe measurement. I took a few points through the travel range and plotted it.

Presumably this entire curve can be shifted downward by setting static toe to zero. The vertical line in the graph is roughly where I think ride height will be. Keep in mind travel will be limited to maybe like 3" total by the coilovers, with most of the action happening between 7.5" and 10". Some conclusions we can draw here: as the car squats, wheels will toe out very slightly, then start to toe back in near full compression. But this change is so small I don't think it will be noticeable, and the flat, predictable toe curve during a corner is probably desirable. However during droop, the wheels will toe in. For a mid-engine car, this could perhaps mitigate some lift-off or "snap" over-steer, since as the outer tire gets unloaded during a throttle lift-off, it will start to point inward, causing some under-steer to balance the sudden increase in camber. I don't know, I'm just some guy with a tape measure. Feel free to provide your own insight.

Dumb question, but did you set tire pressures? Right tire looks a bit soft, but it may be a shadow.

In reply to PMRacing :

Valid question, and no I did not.

Rear suspension is done for good, I think. And yes - the tires were aired up properly! To button everything up, I had to take it apart for the last? time hopefully.

CV axle rebuild was first. Both axles each had a torn boot. New and rebuilt axles are available, and a good idea considering the donor car's 200,000 miles, but this is the Challenge so instead I threw a $15 boot kit at each side. Of course the right side axle had a torn outer boot, which meant I had to pull the inner CV joint apart too. That was a good thing though, because that joint's grease poured out like thin used oil. Fresh grease all around should hopefully prolong the life of these axles. 

Then I finished the toe link mount by boxing them in. This is the only modification to the Toyota engine subframe. 

And bolted everything up. The yellow paint might be a bit tacky but it matches the coilover springs and will make it easier to check for cracks on all my homemade fabricated parts. I also cleaned up the brake caliper, re-greased the slide pins, and installed fresh new hoses. Ready to bleed once the fronts are hooked up.

Next major push: get that engine running? That means figuring out the coolant plumbing (already have a bunch of hoses and pieces), fuel system, vacuum line cleanup, intake and MAF housing, and of course the wiring harness.

Put a triangulation on that swaybar mount.  Just a simple pair of 1" x 1/8" strip going to the top and bottom would do it so like 8" of steel per side.   or alternatively you could just go down to the bottom with a piece of tube.  The swaybar will want very rigid mounts otherwise it could result in some weird behavior as it will behave as 3 springs in series.   I also wonder if you going to want triangulation on that Rear square behind the engine.  A sheer aluminum panel will probably work.  Any "twist" going into the chassis will tend to try to deform that section.  A 3/4" tube running across it (even if it needs to be bolt in for maintenance access) will help.  

Otherwise your work and diligence to double check your work continues to impress.   Sorry this input would of been better before you painted, however I didn't know what "done" was until it was painted.  

Brad agrees with your color choice. So does LMP360. I'd say you're in good company

In reply to nocones :

No worries, the community involvement is the main reason why I post.

Yes, the sway mount on the spindle bracket is probably a bit flimsy. I figured the CG being lower and mass being less than the Avalon meant the loads on the sway bar might be less. But also tires will be stickier, so who knows. Now I'm curious about the effective stiffness, so I might have to fire up the FEA software... 

I wonder about that rear square area too. I could probably just drill some holes and bolt in some diagonal tubular strut members (think shock tower bracing), which would make access easier too. Also keep in mind the front vertical plane of the 'tubular powertrain box frame' is triangulated pretty well.

Bleeding brakes is easy when you can reach half the calipers with a hand on the pedal! Only one leak at the rear circuit tee, but tightening it fixed it. 

I love checking in to your progress!  Keep it up.

Are you sure your upper front control arm is assembled right? Mine sandwiched the chassis.  Sorry if I missed a discussion on this earlier.

Ref pic of Stampies car:

In reply to Brotus7 :

Good eye! There was a running change on the suspension arms from "inside the box" to "outside the box". Mine being an early S2 means it has the rear UCA inside the box. It's a completely different UCA design and spacing of the welded bushings inside the frame box.

S2s were different than Twin Cam for upper control arms...

The change was at car 2584. Early cars (type 46, and early type 54) had one arm in the "box".  Late cars including Twin Cam were outside the box.  Same part numbers for the front arms for all but the very first S1's, rear arm changes at 2584 and continued to end of production (S2 and Twin Cam).

Thanks Roddy for accurate change point!

Got the fuel line and vacuum hose hooked up to the engine. The other end of the fuel line connects to the pump and sending unit, but no tank for that yet. Also looped the heater for now and started gathering coolant plumbing parts. 

Heater loop:

Initial location for a filler cap

Fuel and vacuum lines

Idea for hose on the other side of the engine

And while waiting on plumbing parts I started hooking up the harness. I am not tuning this ECU (for now) so I have to deal with the immobilizer. The plan here is the same as Datsaniti - plug everything in, get it running, start unplugging stuff, then trim the harness down to the bare minimum.

The power distribution module wants to exist in the left rear part of the frame above thet trans. The battery will be just forward of that, near the left coilover mount inside the perimeter of the frame. I am planning to use the trusty wallmart U1 lawn tractor battery for both size, weight, and cost. The stock intake will work to get it running, but it's too big to fit under the hood. I will have to cut the MAF mount out of the intake box and glue it to a pipe.

Is where that heater loop is hooked up locations that won't make it path of least resistance? I've seen people loop heater hoses before where all they accomplished was diverting most of the coolant into a circle of hot engine and never getting to the radiator. I plug the heater ports on anything I'm working on to prevent that situation.

In reply to Asphalt_Gundam :

That totally makes sense. I am planning to eventually run the heater core but I can plug the hoses for now.

I'm getting ahead of myself here, but I bought a battery and started hooking up the harness just to see what would happen. I jumpered all the ground points together and tied them to the frame, though I might have missed a few. 

And it's...awake? I was able to key on, communicate with the OBD port, crank the starter until the oil pressure light went away, open the throttle via the e-pedal, and even confirmed spark by pulling a coil out and putting and extra spark plug in there!

Codes: P0504 brake switch circuit a/b corelation, B2799 immobilizer malfunction, P0453 EVAP sensor/switch high, P0113 IAT high, P0102 MAF circuit high.  The first two might might be related to the shifter, which I don't think was fully installed or grounded judging by the lack of shifter lights illuminated in the cluster. There were also some broken wires near the buzzer for keyless entry, maybe related to immobilizer. I unplugged a few vacuum solenoids (engine mount and airbox flapper), and also the MAF was unplugged, so no crazy surprises yet! 

The harness still has the fuel pump plug, but don't have a tank yet. I'm not too keen on just dropping the pump/sender unit into an open bucket of gas, but short of a building the tank or buying an inline pump fed by a hose from a jerry can.

Asphalt_Gundam said:

Is where that heater loop is hooked up locations that won't make it path of least resistance? I've seen people loop heater hoses before where all they accomplished was diverting most of the coolant into a circle of hot engine and never getting to the radiator. I plug the heater ports on anything I'm working on to prevent that situation.

I've seen the exact opposite a number of times, people plug the heater lines which blocks a necessary coolant pathway that the engine needed.   This is very much an engine specific thing and varies.  

Getting closer, exciting to see. Sounds like you will need to build a tank to mount the pump/sender to be able to proceed, completely agree with not being comfortable with open buckets of gas and electric fuel pumps! 

Sonic said:

Asphalt_Gundam said:

Is where that heater loop is hooked up locations that won't make it path of least resistance? I've seen people loop heater hoses before where all they accomplished was diverting most of the coolant into a circle of hot engine and never getting to the radiator. I plug the heater ports on anything I'm working on to prevent that situation.

I've seen the exact opposite a number of times, people plug the heater lines which blocks a necessary coolant pathway that the engine needed.   This is very much an engine specific thing and varies.  

Yeah, I've heard it both ways, so it probably is engine dependent. 

Here's a cooling system diagram. Only difference is mine doesn't have the oil cooler option and its two hoses.

To me that looks like (7 -from heater) heads right back to the water pump and would cause a shorter/easier route that would bypass the radiator.

Yeah that looks like a Plug or obstruct situation.  I need to do this analysis on mine because I just looped mine and it's probably not the right way to go.  

Edit:  And a quick McGoogle confirms I need to obstruct or block mine vs. loop it.  This could explain why It seems that I have low radiator fluid flow.