Lowering the Nose of my TCS

[thehackmechanic]

While my '74 Federal-spec TCS is off the road over the winter, one of many projects is to address some front end issues. These include ball joints and tie rods that have had the boots completely dissolve during the car's 40-year dormancy, and a broken front sway bar upright link.

But while I'm doing that, I wanted to address the fact that, since it's a Federal-spec car, the nose is as high as a boat on plane.

I've read many posts about lowering the nose. Below is my understanding. Do I have it right?

--Unlike the vintage BMWs I'm familiar with, I can't simply put shorter springs in the front or cut a few coils off the springs I have, because the spring perches are fixed to the shocks, so the car won't just settle on the shorter spring.

--Thus I'd need shocks (e.g. Spax or Avos) with adjustable spring perches. (Although I assume that if I had Spax shocks with the big threaded non-adjustable perch on the bottom, I could make some sort of a spacer to shorten the springs, right?)

--Even with that, it seems maddeningly difficult to find posts where people say "THIS is the name and part number of a set of front lowering springs that settles down the nose a few inches."

--And even if I DO that, I need to do something with the front sway bar to make the upright links adjustable since the length will need to change if the ride height changes, right?

Is that the basic gist of it?

Thanks.

--Rob Siegel

[Certified Lotus]

Rob, I have AVO shocks with adjustable perches and 10 inch springs on the front of my 72 Europa. Prior to the 10 inch springs I used 8 inch springs because I really like the low stance, but the sway bar kept hitting the road on medium bumps and I was always hitting the bump stops. I went back to the 10 inch springs and haven’t had a problem since then.

Great to meet you at LOG39 this summer. Did you fix your overheating problem?   We spoke about the direction of the fan blades on your electric radiator fan.

[thehackmechanic]

Yes, I remember meeting you and chatting. Thanks for asking about the overheating issue. The fan blade orientation appears to be correct, but someone else diagnosed that it appeared that the fan simply wasn't pushing air all the way through the radiator, likely because it was a cheap ill-designed Chinese-made fan. I bought a proper Spal 10" pusher fan, but haven't had the chance to install it yet.

[BDA]

As you say, original shocks don't have adjustable spring perches. If you wanted to keep those shocks you could lower your front end by cutting some coils off your springs. Cutting your springs will increase the rate so might then want to readjust the balance by increasing the rate of the rear springs. Having done that, you may find that your shocks are no longer stiff enough for your stiffer springs.

Lowering the front will increase the danger of your anti-roll bar getting hit if you hit a pothole or a speed bump too fast. I've lowered my car fairly drastically and I haven't had a problem yet. You can make adjustable drop links by cutting off the top mount and threading the drop link and screw on a female rod end to replace the top mount to raise the bar but the shock mounts on the bottom of the shocks is still a potential problem. There are ways to mount the bar above the steering rack with drop links to the lower shock mount bolt.

There are several ideas about what to do with your shocks and springs. I believe Europa Engineering and SJ Sportscars have shocks and springs that are "updated and lowered." Dave Bean and r.d. may also have similar kits. They would certainly be able to advise as to adjusting shocks and recommended ride heights. My advice is to check in with those folks and pick the set that seems the best for you.

[surfguitar58]

There are several threads in this forum discussing what the proper shock and spring combo is. I am patiently waiting for the post that starts: "And so we agree, the perfect shock and spring set-up for a TCS  is... [specs and part numbers]". Still waiting...

Has anyone tried lowering the front with adjustable shocks, along with fabricating shorter anti-roll bar links to keep the sway bar up? Somebody here recently said the Japanese seem to have figured out a good looking TCS stance. What does "Technical Shop Happy" do for front suspension?

Tom

[1970EuropaGuy]

Hi Rob,
On my S2 I just cut the springs down and it worked out great. I'll have to look to confirm but I cut approximately 3 inches off and it lowered the front about 1 1/4 inches. I noticed a very "nice" increase in front end stability as well. The car just settled to the new ride height. I'm thinking of buying some new shorter springs next year if my wife will let me!!! Yeah, it's the cheap way to do it but I'm a bit of a hack mechanic as well.

I have enjoyed your Lotus Europa articles by the way. I miss my BMW 2002!

[EuropaTC]

There are several threads in this forum discussing what the proper shock and spring combo is. I am patiently waiting for the post that starts: "And so we agree, the perfect shock and spring set-up for a TCS  is... [specs and part numbers]". Still waiting...

Has anyone tried lowering the front with adjustable shocks, along with fabricating shorter anti-roll bar links to keep the sway bar up? Somebody here recently said the Japanese seem to have figured out a good looking TCS stance. What does "Technical Shop Happy" do for front suspension?
Tom

now that first question is a good one.......   with as many answers as forum members !   

So on the second point - yes, photos attached.  Unless you re-site the roll bar (Rod did that ?) then the limit is when it comes up against the front shield plate to the chassis, but you can still gain an inch or so of added clearance.

The lowest part is still that pin attachment at the lower wishbones, but that's fixed to the suspension and travels with it, the height not determined by your ride height but the wheel radius.  Low profile tyres and it's dropping but if you retain the OEM rolling diameter when changing tyres - eg going 175/70x13 to 195/50x15 (a guess, not checked but you get the idea) then you'll have the same clearance at that point all the time.

Lowering will bring the central parts down because being fixed to the chassis they don't move like the outer point, so adjustable links do make a difference there. I made mine so I could retain the same geometry at the outer fixing points, no other reason. If you lower suspension without doing so it means the rest position of the flat portion of the bar is at a slight angle & compressing one side the rubber more than the other.  I realise it does that as it moves but I just wanted it to be "looking as it should" at normal ride height.

Brian

[Pfreen]

I have lowered my front end and raised the sway bar as far as possible.

My front height measured to the lower A-arm bolt is 5-7/8” and the sway bar is as high as it can be with it mounted under the closing plate.  The bar misses the closing plate folded edges by an 1/8” or so.   I made the adjustable drop links by cutting off the upper bushing eyes and threading the 1/2” drop link with a 1/2-20 die.  The links attach to the upper A-arm bolt with rod ends threaded onto the drop links. 

I have the SJS protech shocks.  I have SJS springs up front.  I don’t know the free length but they are 250lb/inch rate.  I also have sjs shocks in the rear but I recently changed the stock spring to Dave Bean’s 13” long, 115lb/inch spring.  This allowed me to lower the rear to the measured 6.5” distance between the lower link transmission mount bolts and the ground.

I have the SJS springs set at 8 clicks firm.

I am very happy with the stance and the handling. I have stock tcs tire sizes.