1965 COUPE STOCK REAR SPRINGS AND SHOCKS NOT SNG

[gtjoey]

Now my cousin has the bug but is going stock ....
The SNG ones are too high , WOODHEAD? ,MANNERS?
What makes it ride old school but THE RIGHT HEIGHT?
Anyone.
Thanks in advance.
gtjoey1314

[mgcjag]

Joey...you posted a while back that with your SNGB setup the car sat purfectly viewtopic.php?f=4&t=18982&p=153661&hili ... gs#p153661

[gtjoey]

I went to gaz.....
The rears were 2 inches 2 high......
He is looking for an oil shock stock feeland height,The boge/girling shock WAS great but the COIL height was off
Gtjoey1314

[Heuer]

SNGB have bought the Girling company and archives and are now producing branded/boxed shocks to original specs. They also doing the same with cylinders/pistons along with uprated ones.

The only other option was Boge but they have ceased production. Pretty much anything else will change the handling (Monroe, GAZ etc) or ruin it (Koni). The shocks do not dictate ride height, that is down to the springs at the rear or torsion bars at the front. The latter is easy to resolve with an adjustable torsion bar reaction plate, the former requires springs of the correct spec (height).

[gtjoey]

David, Yes I was asking about the SPRINGS........Th sng springs are too high, they only make one spring.

[Heuer]

Ah, OK. David Manners supplies Woodhead springs IIRC.

The SNGB springs have a rate of 313lbs and the originals 269lbs. Spring rate being defined as the force (weight) it takes to compress the spring by 1 inch.

This was the original spec of springs:


Original springs: 10 coils, 0.432" (11mm) dia wire, 2.9" coil diameter, colour code 'Red'.
SNGB springs: 10 coils, 0.475" (12mm) dia wire and 2.9" coil diameter.

The torsional modulus for any steel likely to be used in car springs is the same, so wire
size matters. Spring rate varies with wire size, no. of active turns and mean coil diameter. A high spring rate will mean the weight of the car will not compress them as much so affecting ride height.

You can use this to calculate spring rate: http://faq.f650.com/FAQs/ShocksSpringRa ... Calculator

When Norman Dewis was testing the E-Type he had a choice of springs (identified by red, yellow, blue, green and white paint blobs on the coils) to choose from. He signed off on 'Red'.

Why not use the original springs; just measure them and if the free length is 10.5" you are good to go? Also the 2+2 cars apparently had spacers on the springs to compensate for the extra weight but I don't know the part number or whether this is true!

Anybody have a known original spring photo, compared to an SNGB one even better?

[mgcjag]

BCC or CMC.......I know cars with springs from both with correct ride height.....but then iv also had correct height with SNGB Springs.....both their standard and Girling that iv worked on....never had a spring that gives 2in too high ride height......Steve https://britishclassiccarparts.com/coll ... spring-set
https://www.classic-motor-cars.co.uk/pr ... uspension/

[Heuer]

I believe CMC had their own springs made as they were unhappy with the specs of others out there and as are close as you will get to the originals.

[Tom W]

Rear dampers do affect ride height as they’re coil overs. Specifically the relationship between the spring seats and the eyelets needs to be correct. It’s the same principle as using adjustable platform dampers to adjust the ride height.

[mgcjag]

Toms post above just reminded me....i have seen a car sitting way to high as a result of useing SNG standard springs on the adjustable height Gaz shocks.....these shocks are designed to use a shorter spring....Steve

[Jeremy]

I believe CMC had their own springs made as they were unhappy with the specs of others out there and as are close as you will get to the originals.

I bought the CMC springs for my restoration on that understanding. Ride height is spot on, comfort and handling (with the Boge shocks) are excellent.

[Allrand]

Rear dampers do affect ride height as they’re coil overs

Sorry to disagree Tom, shocks do not affect ride height, nothing to do with them being coil overs, unless they're non-standard, adjustable height or gas filled which exerts lift.

[bitsobrits]

Sorry to disagree Tom, shocks do not affect ride height, nothing to do with them being coil overs, unless they're non-standard, adjustable height or gas filled which exerts lift.

I think you and Tom actually agree: They do affect height if they are not made correctly, i.e. if the spring seat is too high, which you call non-standard. Parts may be labeled as suitable for a particular application when they are not to OEM spec.

[Heuer]

If you only install the springs without the dampers you should get the correct Factory ride height. Adding spacers to the spring mounts will increase ride height, cut the springs and you will decrease the ride height. The shock absorbers, when fitted, are there to moderate the effect of the springs and no more. Adjustable shocks alter the stiffness of the damping.

There was a monster thread on Jag Lovers covering this subject; check it out if you want confirmation: https://forums.jag-lovers.com/t/e-type- ... ocks/71370

[mgcjag]

Just had a quick skim through that JL thread....there is some real nonsense in there. ........If were not carefull then this thread will go the same way as the JL one..with most thinking the same thing but it comeing across as we all have different ideas..........Steve

[Tom W]

Agreed, a lot of miss information there.

I think most of us agree, but for clarity, there are three things combined that go together to make up the rear ride height on an E-type.

1. The distance from the top eyelet to the top spring perch.
2. The laden length of the spring
3. The distance from the bottom spring perch to the bottom eyelet

Change any one of those three and the ride height changes. Points 1 and 3 are dimensional characteristics of the damper component because of the coil-over design. The damping rate in both compression and rebound makes no difference to the ride height. Adding packers or spacers effectively changes points 1 & 3.

Changes in spring rate, spring free length and laden weight affect point 2. Using gas charged dampers reduces the load experienced by the spring so, for a given spring, there’s an increase in laden length.

[dlgis]

I had the opposite problem with SNGB standard springs on mine with the car sitting too low. Replaced all 4 rear shocks/springs with SNGB Girlings and it seems spot on to me.

[mgcjag]

Lots of replies and info but no response from the OP Joey .......Steve

[Series1 Stu]

I'm keeping out of this one, despite there being so much bad logic here.

It's not worth the derision.

[gtjoey]

I had asked the question after many calls...
The SNG coils sit at 275.compression rate
The Moss and CMC are at 233. compression rate
Im running GAZ so Im out, but remember my car was sitting the same 2 inches too high thats why I switched. He will be trying the Moss springs which are the same supplier from England where the SNG are made from a separate supplier.
Supposedly the Woodhead are the same as Boge on the shock side but the spring is the same as the Moss spring.
Hope this helps.
Spring will set the height the shock is just the hedge .....it all works together.
But ALL are supposedly one supplier EXCEPT for SNG .
Once he jumps on it I will forward pictures....
gtjoey1314