Thoughts on this style of Coil Over

[fisch]

I don't know jack about coil overs, but I need to think about it as when I get my 510 inspected they give me a hard time because the cut front springs move around when the car is jacked in the air. And in MA you don't want to give them an excuse to fail you.

 

Anyway, this seems like a pretty swell idea. No need for welding or even a Splitcollar. It has a cap with a hole that slides over your existing strut tube (Gotta cut off the old perch naturally.) and three allen head set screws that hold it in place.

 

I know of the ebay ones and the T3 and the GC and on and on, but this seemed novel. I guess I could also just cut the perch and use a split collar to raise it up.

 

Any one know who makes them?

 

 

[datzenmike]

I believe the allen screws only space the threaded sleeve evenly on the strut tube, they don't support or hold the weight of the car, at least I would never risk this! Get $25 split collars and set them on the strut tube underneath and let those sleeves sit on them. Way safer.

 

I MIGed a small weld under the split collars just for insurance. These can easily be ground off later if need be

[Laecaon]

My coilover springs still rattle when I lift the car.

 

There are a few cars that will do this OEM. This actually just came up on a Datsun facebook page about a week ago.

[fisch]

I wondered that. I wondered if I tightened the perch high enough to take up the slop so the spring won't move, would that also raise the height? Silly really because it isn't like you can get teh spring out with the strut tube running through the center of it.

[RedBanner]

That is how you raise the ride height.

Great art tho.

[datzenmike]

The only true fix would be a slightly longer spring and re-adjust the height again. Unless they raise the vehicle with the wheels hanging free, no one will know.

[fisch]

The only true fix would be a slightly longer spring and re-adjust the height again. Unless they raise the vehicle with the wheels hanging free, no one will know.

That is what they do. The raise the wheel off the ground to check the ball joint play. That is when they see how lose the spring is when there is no pressure. The last guy paused, but in the end just told me not to go over any jumps and passed me. LOL.

 

Banner, that is what I figured. I just couldn't think of a way around it.

[datzenmike]

Well you could raise the ride height just enough so the spring isn't loose when raised and then lower it again after.

[q-tip]

They make "helper" springs that completely compress when the car is on the ground but take up the space when you jack it up. Down side is it lifts the car whatever the fully compressed length of the spring is.

[Three B's Racing]

I'd use the split collars fisch as those allen set screws I would never trust. So it the 510 now road worthy? I'm in Southern NH, we should take a drive up to Chris's sometime. Next year is the 20th East Coast 510 Meet at Summit Point, you should make plans on attending as it should be a really good one. You and I could caravan on down if you'd like. It would be like old times with Chris.

 

Lou

[thisismatt]

I was going to suggest helper springs as well. You just lower the perch to compensate for the added length.

[Dime Dave]

Longer springs alone aren't going to help unless you soften the spring rate up. If the rate stays the same, the seat will just be lower down the tube when adjusted to the same ride height.

 

This may be over simplified but say you have a 250# spring rate and the front of the car weighs 1000# (500#/side). Sitting on the wheels, each spring supports 500# each and at the 250#/inch rate, the springs compress 2". If you lift the car by the body so the suspension droops, any droop travel beyond 2" will produce a loose spring.

 

Most suspensions when sitting at ride height are designed to have 50% droop travel (wheel moves down relative to the chassis) and 50% bump (wheel move upward). Typically the struts used in a 510 have 6-7" of total travel. Using 6" of total travel, in a perfect set-up you would have 3" of bump & 3" of droop. If this is the case with your car, it gives you 1" of free play at the spring when you lift the tire off the ground by jacking up the chassis.

 

To take up the 1" of loose spring travel you would need to either raise the ride height 1" or change the spring rate so it compresses 3" with the 500# load sitting on it, or 500#/3" = 167#, or a 150# rate would work.

 

Now if the car has stock-ish spring rates, say 100# springs, they would need to compress 5" to support the 500# load at ride height. With only 3" of droop travel the spring needs 2" more extension to become loose. That 2" more extension @100#/1" equals 200# pressure on the spring seat. This is why spring compressors are needed to remove softer rate stock springs.

 

In reality the springs are captivated by the strut going thru the center of them. There is no way they can fall out. Not sure why the inspection guy is cranked up about them being loose when you jack up the car.

[DaBlist]

Limiting straps

[fisch]

LOL this thread became way more informative than I thought it would. Very cool. And Dave, that makes total sense to me. Inspectors here in MA are all on a powertrip. They enjoyed my car, cause they've never seen one (young) but were surprised it passed. (Which probably has to do with Chapman's uhhh... 'patina'?) I think part of it is that the wheel has some up and down movement with the cut springs, so when they check balljoints they feel that and it puzzles them because they usually only inspect new cars and feel nothing that dramatic. Twice with two different inspectors it has been noted, but they both let me pass. Makes me wonder if they CAN'T fail me for that. Ball joints are fine after all.

 

And Lou, Chapman is running aces right now! I haven't driven him more that 20 miles away in my ownership though. Chris has been helpful the last few weeks advising me on Chapman, even 5 years after he sold it. Great guy. Be a hoot to drive it up to see him. Built a hell of a car here. It was a joy to rip around on it today. Something to think about. I jokingly said to my wife that she should drive the 510 Wagon down to Summit Point, and me in Chapman, and well, she didn't say no, so who knows? If so I will totally let you know.

[ByStickel]

Limiting straps

 

I was going to suggest large zip-ties to hold the spring to the springs to the seats.

 

What goes on in these Mass inspections? I'm about to move that way and am wondering if my N.C.street-legal road race car (no inspections, here) with a carbureted 1964 V8 has a chance at passing. And are they careful where they lift the car, or are my rockers going to get crushed once a year?

[fisch]

Tail lights, turn signals, reverse lights, high beams, low beams, signals. The usual. They jack the car to check the ball joints. They asked me where the jacking points were thankfully. They don't look under the hood.

 

Where they've failed me is:

 

-Windshield washer fluid. Yup, it has to squirt if it came with your car stock.

 

-Seatbelts for all seats. THey check that they work.

 

-And I was failed because I had a rust hole the size of a pencil eraser on my rocker panel. They claimed exhaust could get in the cabin. Which is silly.

 

-I also had too much rust on the tail gate of my 521.

 

For instance the factory hole plug was missing on my floor in my truck. He said I had to be covered, again because exhaust could get in I guess...

 

I think some are more assholeish than others. I've been to three different ones. All had their issues.

 

Good news at least is no smog for cars older than, heck maybe 94 by now.

[ByStickel]

Thanks for the info.

 

I was looking at Northampton, which is really close to you. I might bother you for some local info, if that's OK.

[Roadster-ka]

Zip ties break, been there

[datsunfreak]

Zip ties break, been there

 

Safety wire?