Measuring for tube shocks

[3739ford]

What is the rule of thumb for how to measure to get the correct tube shocks?

[paul2748]

I was told and what I use is that it should be static mounted at the middle of it's travel so it has equal travel up and down. Not sure that is the correct way though, but it works for me.

[JSeery]

You need to know the range of the chassis movement. You can jack up the frame until the tire is just about to clear the floor, that would be the maximum travel. The minimum travel is where the frame would contact the bump stop.

[SofaKing]

I was unable to find a tube shock with anything like the travel of a Houdaille. I googled a chart with shock dimensions and bought some for a 99 Mercury minivan, Villlager, I think. Mounting them on the back of my truck taught me the meaning of "compromise". I set mine up so they have compression just in excess of the travel to the Bumpstop, about 6 of the 9 + inches of travel. The rest is extension. They have the mounting eye on both ends. I am pretty close to 15 degrees from vertical but the lower shock eye is very low and visible. I don't claim it's ideal, correct or rule of thumb, it is simply the compromise I made, working ok so far but I don't pull negative g.

[3739ford]

Thanks for the info, I was planning on replacing the Houdaille, with tube shocks. I ordered the axle bumper stops last night and working on installing backing plates so I can get the wheels/tires on. Right now the bare frame has easier access to make the changes needed for tube shocks. I thought I understood how to measure just needed backup from you guys.

[TJ]

Sponsored Links (Register now to hide all advertisements)

Originally Posted by 3739ford

Thanks for the info, I was planning on replacing the Houdaille, with tube shocks. I ordered the axle bumper stops last night and working on installing backing plates so I can get the wheels/tires on. Right now the bare frame has easier access to make the changes needed for tube shocks. I thought I understood how to measure just needed backup from you guys.

If you are still working with the bare frame you don't want to measure for shocks until the body and all accessories are on the car.

[JSeery]

Not necessarily, you are looking for supension extremes to determine shock travel length.

[philipswanson]

Originally Posted by JSeery

You need to know the range of the chassis movement. You can jack up the frame until the tire is just about to clear the floor, that would be the maximum travel. The minimum travel is where the frame would contact the bump stop.

This didn't work for me because the bump stops on my wagon are way higher than the spring would ever allow. Using this method, I would need 18" of travel. You would never find a shock with that and you would never need that much. I settled for using the method of centering the shock in it's stroke to the static position. Worked great using Bilsteins. Bilstein doesn't release upper and lower limits so I had to cross reference an application using Monroe's chart. Turned out to be a 1991 Mitsubishi Montero SUV vehicle.

[Ol' Ron]

The biggest problem I find with shocks is finding a reasonable priced shock of the right travel and valving. Searching through the thousands of shocks valuable, I found that the 70's 8o's mid size Chevys had a 30/70 shock. Unfortunately they were alittle long and had the wrong end on the top. I made an adapter for the aftermarket shock brackets and now have a great ride for around a hundred bucks all around. I like to make things, I should take a pic of these, but their on the truck. However, I have to make another set for a friend and I post them

[19Fordy]

In the thread below there is a Monroe shock length chart;
https://www.fordbarn.com/forum/showt...e+shock+length

[Pete]

Shocks are almost as much a black science as is cam grinding.
Most people just select a shock that mechanically fits in the space available and is recommended by the seller or a friend.
This method has about as much merit as running no shocks at all.
If you want to have your car ride like you think it should, you are going to have to learn how shocks are rated. Different brands use different rating numbers.
Shocks come in different diameters and bigger is not necessarily better.
They are rated in compression and rebound percentages represented by numbers.
You need to learn these numbers in order to locate what you want.
Percentagewise, a good place to start is either 60/40 or 70/30. That means 60 percent compression and 40 percent rebound etc. For example, a certain manufacturer will rate a
60/40 shock as a number 4. etc etc.
A good source of a wide variety of shocks is Ebay.
LOOK FOR RACING SHOCKS.
Don't believe all of the hype that gas shocks are too stiff. If a shock has a certain rating, it doesn't matter what it is filled with. It will have that rating if it was filled with anything.
The number will be different though.
A 2 or 3 inch diameter by 7 or 9 inch long race shock will fit many hot rod applications and
a used race shock will generally last for many years on a street rod.

Another BIG advantage of race shocks is, most mount with the body UP.
This means LESS unsprung weight which is what you want for a more comfortable ride.

[tubman]

Originally Posted by Ol' Ron

The biggest problem I find with shocks is finding a reasonable priced shock of the right travel and valving. Searching through the thousands of shocks valuable, I found that the 70's 8o's mid size Chevys had a 30/70 shock. Unfortunately they were alittle long and had the wrong end on the top. I made an adapter for the aftermarket shock brackets and now have a great ride for around a hundred bucks all around. I like to make things, I should take a pic of these, but their on the truck. However, I have to make another set for a friend and I post them

I think Ron just explained everything.

[alanwoodieman]

I have been using chevy van shocks from the 70/78's, been working for about 25 years so far on my 40 wagon.

[Ol' Ron]

Another thing about shocks. They have a weight rating, although I never see this anymore. at one time they had a chart on the weight of the car the shocks a valved for. You wouldn't us a shock from a Lincoln on a Pinto.

[D. Jones]

I cheated and used the shocks for a 1956 Ford 1/2 ton on my 1945 commercial after I measured the 56 every way I possibly could. I built my own mounts for front and rear and a cross member for the top rear mount. So far everything seems to be working very well.

[philipswanson]

Measure static between mounts, upper and lower. Go to Monroe tables and pick a shock with the same ends you need. Determine the one with your static measurement half way in between the upper and lower limits. Look up the vehicle that this fits. Now go to Bilstein and look up their shock number that fits the same vehicle. You're done. Much better than Monroes. Go to E Bay for a super deal.

[SofaKing]

I have been as unsuccessful finding the valving numbers for shocks as I am unsuccessful finding the country of origin for brake hoses I currently need for my Jeep. The latter I am sure is deliberately hidden, the former probably.

[1948F-1Pickup]

Originally Posted by philipswanson

Measure static between mounts, upper and lower. Go to Monroe tables and pick a shock with the same ends you need. Determine the one with your static measurement half way in between the upper and lower limits. Look up the vehicle that this fits. Now go to Bilstein and look up their shock number that fits the same vehicle. You're done. Much better than Monroes. Go to E Bay for a super deal.

This is basically what I did to order the Viking shocks on my F-1.

[3739ford]

Nice pictures of the shock/mount. I would love to see more pictures guys of your vehicle shocks. I'm still at that point of making shock mounts and purchasing shocks.