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-   -   Front bag cup size (https://67-72chevytrucks.com/vboard/showthread.php?t=142636)

kdogg 02-24-2005 04:55 PM

Front bag cup size
 
Hey whats up guys. Just wondering if anyone can give me the dimensions of their front lower bag cups. I.E. the total height, along with the diameter of the tubing used. Any help would be appreciated. Thanks.

Alvin 02-24-2005 05:34 PM

Most guys like double D's, but I've always been a fan of the smaller ones...

oh wait...

Alvin 02-24-2005 05:50 PM

4 Attachment(s)
Here's what you're looking for. I just so happen to have two pairs of cups, each from a different manufacturer. The first one is from ***************** and is built like a tank, but it's a little big. It is 5.5 inches across and 2.5 inches tall. The cups from AirRide Technologies are 5 inches across and 1.75 inches tall (more like 1 5/8, but I round up :rolleyes: ). I will say that I prefer the way the AirRide bags sit in the pocket on the control arm. I just wish I had the smaller cups made out of the thicker material, but no sense in buying a third set.

kdogg 02-24-2005 07:56 PM

Wow that was just what I needed to know and you even put in pictures. :metal: Thanks a lot for your time.

TheFabShop 02-24-2005 08:37 PM

I use 5" od by 1/4" pipe also on theses trucks works great.The height is going to depend on your over all tire height.

XXL 02-24-2005 09:11 PM

Quote:

Originally Posted by TheFabShop
The height is going to depend on your over all tire height.

What does tire height have to do with bag positioning? The bag location is defined by the geometry of upper and lower control arms... which are in exactly the same place whether you're using 175/80-R13's or Monster truck tires.

TheFabShop 02-25-2005 11:32 PM

Ok XXL if your lower cup is too tall it may not lay all the way out with a say 28" tire but it will lay out with say a 27" tire do you understand now?

ricecop425 02-26-2005 04:15 AM

i got the suicide doors and just cut an inch of the bottom

XXL 02-26-2005 11:58 AM

Quote:

Originally Posted by TheFabShop
Ok XXL if your lower cup is too tall it may not lay all the way out with a say 28" tire but it will lay out with say a 27" tire do you understand now?

Yes, I understood what you said in your previous post, and it was incorrect. I also understand what you're saying here... which is that tire height (divided by 2) is directly related to overall vehicle height. Thanks for the clarification.

TheFabShop 02-27-2005 12:36 AM

So you are sayin I am wrong?

XXL 02-27-2005 01:16 AM

Quote:

Originally Posted by TheFabShop
So you are sayin I am wrong?

In your first statement, yes. You are wrong. The bag height has zero effect on the size of the tire. The bag height determines the height of the spindle (as it arcs in the geometry made up by it and the upper and lower control arms). I can set the bag and cup at 8" ride height and that'll be 8" ride height whether I use a spare tire off a '76 Honda Civic (about 15" tall) or a tire off of Bigfoot. Tire size is simply irrelevant.

Having said that, you did correct your statement in your follow-up post. I thought that we were going to move forward from there, but your last post sounds like a "calling out." So you've called me out.

/no reply necessary

TheFabShop 02-27-2005 02:32 AM

The height on the lower cup DOES matter.If the cup is too tall and you are running a tall tire the truck will not always lay out.This is true if it wasn't every cup would be the same height and they are not.87 down trucks have a plate on top and cup on bottom if cup size doesn't matter lets see you run a 22 with a 265/35/22 and a 5" lower cup and lay it out it won't happen.Now if you cut some off the lower cup what happens(the truck sets lower) you see what I am getting at!

XXL 02-27-2005 09:49 AM

Quote:

Originally Posted by TheFabShop
The height on the lower cup DOES matter.If the cup is too tall and you are running a tall tire the truck will not always lay out.This is true if it wasn't every cup would be the same height and they are not.87 down trucks have a plate on top and cup on bottom if cup size doesn't matter lets see you run a 22 with a 265/35/22 and a 5" lower cup and lay it out it won't happen.Now if you cut some off the lower cup what happens(the truck sets lower) you see what I am getting at!

Yep. I understood you 2 posts back... and I told you thanks for the clarification. I understand very well that a tire height has everything to do with the overall height of the truck (divided by 2). And so I'll say it again, and then drop if you still don't get it... your FIRST post in this thread indicated that the height of the bottom cup was dependent on tire height. I say again... no it isn't. The cup height (along with bag inflated height) define the suspension's ride height. That's it. It has nothing to do with the tire size. Now, when you tack on a tire, you further define the vehicle's ride height (again, divided by 2).

TheFabShop 03-02-2005 12:21 AM

the bottom cup was dependent on tire height. I say again... no it isn't .I am saying that if the lower cup is too tall and not the right height it will not lay the truck fully if the tire is too tall!

Shane 03-02-2005 01:13 AM

It won't lay frame cause the tire is too tall ... NOT because the cup is too tall.

A deflated bag is a deflated bag ... regardless of whether the cup is 1.75 inches tall or if it's 2.5 inches tall ... now, if you have 22 inch tires on that same vehicle, then THAT is what is going to prevent the vehicle from, as you kids say, "laying frame." Not the cup.

99% of the bags that are used in the front application will compress to less than 3 1/2 to 4 inches of overall height in a fully-deflated position, some will deflate and compress EVEN MORE ... add that 2 inch cup and you still ONLY have 6 inches of space being taken up at MAX. There is ALOT more than 6 inches of space between the top surface of the top pocket and the bottom A-arm when the suspension is fully compressed (67-72 suspension).

You can even take the lower cup completely out and a stock suspension won't "lay frame" on a set of 15 inch wheels! (earlier debate - does not pertain to this one) It will "lay" the STOCK front crossmember ... but NOT the frame rails.

XXL hit the nail on the head. If you have a 22 inch tire ... divide the OVERALL HEIGHT BY 2, then that will give you the measurement of the portion of the tire (contact patch) that is touching the ground and the centerline measurement of said tire. The larger the tire, the larger the centerline number will become. The larger that number becomes, the more the suspension has to "drop" when you deflate your bags in order for you (again as you kids like to call it) to "lay frame."

For agument's sake, let's use JUST the wheel O.D. & NOT taking into consideration the tire's overall height (rim size +sidewall x 2=O.A.H.)

15 inch wheel / 2 = 7.5" centerline height
22 inch wheel / 2 = 11" centerline height
11 - 7.5 = 3.5 inches

Now, moving right along to the cup heights mentioned earlier.
2.5 - 1.75 = .75 inch

.75 (3/4) of an inch difference on the cup height is NOT going to give you 3.5 inches more travel in your suspension. Simple math says it just won't work.

The suspension geometry is a FIXED number mathematically ... the tire size is the variable.

XXL 03-02-2005 09:49 AM

Quote:

Originally Posted by Shane
...as you kids say, "laying frame."

:phat: :aiiet: :bling2:

Slammed67 03-02-2005 03:43 PM

This is another example of how some people design things just to get "the look" without any emphasis on functionality (and safety in some cases). You should set up your air bag suspension so that the truck is at ride height when the bag is at the recommended ride height. If you are adjusting the lower cup height just so it lays out (frame and/or rocker) with a certain wheel/tire combo regardless of anything else, then it's probably going to ride like crap when the truck is raised up to a decent/safe ride height.

XXL 03-02-2005 06:07 PM

Quote:

Originally Posted by Slammed67

Is part of you bleeding again?

:agree: :phat: :Own:

TheFabShop 03-03-2005 12:36 AM

These trucks will never lay frame in front anyway without xmember sectioned or frame z'd.Yes your suspension will only cycle a certain amount but if lower cup height doesn't matter why doesn't everyone make their cups the same height.I don't know who you are referring to as a kid either.I was just giving the guy some dimensions of what he asked for.I am not trying to be a smart ass or anything but I know how I lay out trucks daily at my shop and things are done right.I am not getting into a pissing contest with anyone here just stating what I know!

TheFabShop 03-03-2005 12:40 AM

Here is a link to some of my work if anyone thinks I don't know what I am doing.http://streetsourcemag.com/im/viewus...?id=TheFabShop
Thanks

Shane 03-03-2005 09:59 AM

Quote:

Originally Posted by TheFabShop
I don't know who you are referring to as a kid either.

Chill Tonto ... it wasn't necessarily meant as a "put down." I didn't realize "you kids" were so age conscious.

Quote:

Originally Posted by TheFabShop
I am not getting into a pissing contest with anyone here ...

uh ...ya sure? :rolleyes:

XXL 03-03-2005 10:08 AM

Quote:

Originally Posted by Shane
Chill Tonto ... it wasn't necessarily meant as a "put down." I didn't realize "you kids" were so age conscious.

Most people don't know this, but Shane is 113 years old... so everyone is a kid to him. Apparently he also recently won some kind of trophy ;)

http://www.co.fairbanks.ak.us/Parks&...arkel%2091.jpg

Shane 03-03-2005 12:56 PM

Trophy was awarded for best engineered and safest suspenion system for the category of senior citizen transportation devices.
(compressed air sub-category - wheel chair/Wal Mart lend scooter).

I would like to thank the Academy for this prestigious award. ;)

raggedjim 03-03-2005 01:36 PM

Shane's a fraud! That's my grandpa and his 60 yard dash trophy...

Rg

XXL 03-03-2005 02:58 PM

:tj:
Quote:

Originally Posted by raggedjim
Shane's a fraud! That's my grandpa and his 60 yard dash trophy...

So your grandpa is Shane? Cool!


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