STUDY! STUDY! STUDY!....Questions for Porterbilt and others "in the know"...

[-Greg72]

I've been doing a LOT of reading on these message forums lately. I'm a lurker here mostly since I rarely have the expertise in the 2WD Chevy world to chime in with much helpful advice.

I am doing some preliminary planning research to drop my '72 Burb and have a few random questions at this point:



1. Is there a version of the "Dropmember" that works with a BBC? I saw some talk about it in a few threads, but never saw a definitive answer.

2. Is there a solution to use the rack-and-pinion setup with something as heavy as a 'Burb and BBC setup? The Mustang and MustangII racks seem to be too light-duty to do it safely.

3. Does anyone use their vehicle for towing with an airbag setup and large diameter wheels/tires? The "look" is awesome, but I wonder if you can get those "steamroller" tires in a Load range "D" for safe towing, or if they'd overheat and burn up/blow out?? I need to tow around 7500Lbs from time to time.

4. How close to the ground can I get without cutting up the rear floor areas (or center tunnel)? Laying frame is not one of my objectives, though I'd certainly like a LOW stance on occasion. The Burb must remain practical and useable as a tow rig and people hauler....so there is a limit to what I'm willing to cut. Getting within a couple of inches from the ground would be fine with me....

5. Does anyone have some nice side profile shots of a 'Burb with the larger diameter tires that they could post? I like the look of some of the Porterbilt trucks with their 20s/22s...but I doubt that would ever work for towing. I'm thinking I may be in the 18s/20s-range or maybe even smaller diameters to be able to handle the heat (and load range) for towing. If people have photos and specific tire sizes used, that would help a lot.


Thanks! There are a lot of amazing trucks here....and it's great to see the AirRide representatives talking in the forums and offering advice.

[PBFAB.COM]

Originally Posted by -Greg72

I've been doing a LOT of reading on these message forums lately. I'm a lurker here mostly since I rarely have the expertise in the 2WD Chevy world to chime in with much helpful advice.

I am doing some preliminary planning research to drop my '72 Burb and have a few random questions at this point:



1. Is there a version of the "Dropmember" that works with a BBC? I saw some talk about it in a few threads, but never saw a definitive answer.

2. Is there a solution to use the rack-and-pinion setup with something as heavy as a 'Burb and BBC setup? The Mustang and MustangII racks seem to be too light-duty to do it safely.

3. Does anyone use their vehicle for towing with an airbag setup and large diameter wheels/tires? The "look" is awesome, but I wonder if you can get those "steamroller" tires in a Load range "D" for safe towing, or if they'd overheat and burn up/blow out?? I need to tow around 7500Lbs from time to time.

4. How close to the ground can I get without cutting up the rear floor areas (or center tunnel)? Laying frame is not one of my objectives, though I'd certainly like a LOW stance on occasion. The Burb must remain practical and useable as a tow rig and people hauler....so there is a limit to what I'm willing to cut. Getting within a couple of inches from the ground would be fine with me....

5. Does anyone have some nice side profile shots of a 'Burb with the larger diameter tires that they could post? I like the look of some of the Porterbilt trucks with their 20s/22s...but I doubt that would ever work for towing. I'm thinking I may be in the 18s/20s-range or maybe even smaller diameters to be able to handle the heat (and load range) for towing. If people have photos and specific tire sizes used, that would help a lot.


Thanks! There are a lot of amazing trucks here....and it's great to see the AirRide representatives talking in the forums and offering advice.

Greg-
To answer the first two questions... The Dropmember and BBC combo is possible and being done. I am yet to do one in house, so there are currently no motor mounts or detailed instructions/pics for the procedure provided by me.

The MII and vehicle weight issue you are inquiring about is an important question. The MII rack and pinion I use, are supplied by Maval Manufacturing (Unisteer). It has been recommended to me, by them, that on a vehicle that has a front axle weight greater than 1800lbs. the MII rack is not recommended. If the front axle weight is near or at 1800lbs. a manual unit is recommended. I was also told that tongue weight or towing weight is not a factor, just front axle weight. With a BBC full of fluids and the burb itself the weight on the front axle will be approaching the limits. I would recommend weighing it to make sure.

From the description you've given, as far as the intended use and application, I really don't think a Dropmember will benefit your application. I would recommend an air suspension all around and spindles up front, and possibly a c-notch in the rear... depends on how much you are really going to be towing.

[-Greg72]

Thanks for the info....

I had planned to go with the full compliment of AirRide gear....C10 StrongArms up front, C10 StrongArm Rear (Tubular Link and C-Notch) along with the LevelPro controller.... so it seems like you and I can still do some business after all, eh?

The ideas that I liked about the Dropmember were that it narrowed the track width from stock, seemed to have better suspension geometry (for handling) over stock, and incorporated a much cleaner looking rack-and-pinion setup. Perhaps it is all just a "matter of degrees".....the ART components will probably be a VERY nice improvement from stock, and that may prove to be enough for me.

I really do appreciate your candor about the Dropmember, it sounds like overkill for what I'm doing.....but it is a beautiful piece of work nonetheless. Thanks again.


Anyone else want to chime in with answers to some of my other inquiries??

[Tony@AirRideTech]

adding the drop member in the front should not be an issue.... I mean in the real world a big block is only a couple hundred more pounds than a small block... thats not even equal to one fat chick. As far as the 7500lb tow capacity..... the total weight of the trailer is not a concern like the actual tounge weight. The total weight needs to be considered on the braking and engine torque aspect. If your tongue weight is still less than 500 lbs you are still in the play ground and also by the time you add that much tongue weight, your front axle will take less air..... until you rail the brakes that is

[-Greg72]

Tony,

I'm thinking that tongue weight is going to be more like 750Lbs (10% of total trailer weight as tongue weight is the rule-of-thumb I've heard). I will probably be adding a load-leveler/sway control setup if that matters.

In your opinion, is the extra load out back merely a problem of selecting a higher rated airbag for the rears, or does the problem become larger than that?

You kind of lost me on your initial comment about the dropmember...or were you referring to the front StrongArm setup being OK for towing, etc????


.

[PBFAB.COM]

Originally Posted by -Greg72

Tony,

I'm thinking that tongue weight is going to be more like 750Lbs (10% of total trailer weight as tongue weight is the rule-of-thumb I've heard). I will probably be adding a load-leveler/sway control setup if that matters.

In your opinion, is the extra load out back merely a problem of selecting a higher rated airbag for the rears, or does the problem become larger than that?

You kind of lost me on your initial comment about the dropmember...or were you referring to the front StrongArm setup being OK for towing, etc????


.

I believe Tony was saying that the front axle weight shouldn't be an issue for the MII rack and pinion, and thus Dropmember. The weight wasn 't my biggest concern, but more the comments about not looking to plant the frame and cutting things. I am trying to find some specs for the front axle weights and will post again when I find em.

The Strong Arms are superior to the factory arms in strength and there will be no issues as for towing.

[Tony@AirRideTech]

actually it will probably be less than 10% as long as the trailer is balanced and loaded porperly over the axles. What rear end are you running in this thing?

[-Greg72]

I understand....

The Dropmember will dump the front potentially ALL the way to the ground, but without serious mods out back I won't get the rear down that far.... probably doesn't make sense to buy the DM unless I really want it for the rack-and-pinion solution. (I'm still reading....not sure I fully understand the benefits yet)

I was planning on buying a set of 4-corner scales before too much longer....so I will be able to get accurate measurements before I start buying the parts.

EDIT:

Tony, I'm running the stock Eaton rear end currently (8-Lug 3/4Ton). I was thinking about either a 12-Bolt or D60 rear to get the 5-lug pattern I'll need, and something with either a full-floating axle or retainers to hold the wheel in place if I ever broke an axleshaft. Losing a wheel while towing would probably be fatal....

[Tony@AirRideTech]

I would try to find you the 8 3/4" 12 bolt rear out of the 88-98 chevs. They put it in the "heavy half" 1/2 ton trucks and the 454SS trucks. I would imagine they were produced for the earlier heavy half trucks but I am not positive.... I know my 90 has one under it. That way you can also get the 5x5 bolt circle and a heavier duty rear end.