PontiacBonnevilleClub.com

I was tossing around the idea of suspension modifications for improved ride and handling. I am convinced, at this point, that no coil spring/strut/shock mod will change the suspension vibration displacement on this vehicle, it is inherit by design (probably when GM switched to using aluminum control arms with steel coil springs, etc. etc etc.). This is also largely due to the environment where the vehicle is driven, but it is what it is. I've already tried different coil combos front/back, and switched out the rear air shocks with gas/oil shocks. The ride is different but still unacceptable, for me.

Its not so much the vehicle involved in the mod. its more in the satisfaction of customizing things for a given purpose and application. I probably will air bag, but will attempt to maintain the stock heights. This will mean longer bags for less air to soften the ride. I know there are some costs and welding work involved, but I need to look into it when the weather breaks. Anyone familiar with this process for this purpose? It is not the typical reasoning that most people go to airbags.

For me, I am really tired of the feeling that I am driving/riding in a train, I guess I'm getting really old or something...

Check with GXP Venom. He put bags on his car, mostly for car show purposes, but he has a good amount of knowledge and experience with them.

Air bags , on the rear aren't that difficult. Remove the rear spring, the airbag has one bolt on the bottom. Slip it through the hole in the suspension arm and fix in place with two large washers and a locking nut. It has two bolts on top which you drill holes in the upper bracket to receive. Take the airline off the rear shock and cut the fitting that attaches to the shock leaving about 3 inches of air line. Put a compression plug on each end of the cut line. tuck the line that goes to the ELC compressor up out of the way and ziptie. Put the small piece of airline with the compression plug and the shock fitting on it back on the shock and let the car down. There is now enough pressure in the shock to assist with the ride. It doesn't mater if it has a real slow leak, if an older one. Zero pressure at you selected ride height will still allow it to work when compressed and expanded as the car goes down the road. Your leaving it in place more for vehicle stability than ride height. That will now be handled by the air bag. You remove the ride height link from the leveling switch and zip tie the switch all the way up so the ELC pump doesn't kick on. Now the next part. Air to the bags. Your ELC compressor wont work for the airbags. You must put a 12V air compressor (I have two) and a holding tank in the trunk.And fill and dump 12 electric solenoid valves between the airbags and the air tank. I have a total of 8 for fill and dump control of all 4 corners. And pressure sensors with digital readouts for exact leveling from inside the car.

Now ride comfort. Ride comfort can be much softer with rear air bags. Or harder. Depends directly on what pressure you put in them, and there is amount of slack as to pressure vs height. I have custom made struts on the front with "airbag collars" that replace the front springs. I want to make it clear here that front air collar struts are only for ride height adjustment. They are much, much stiffer than OEM. At any pressure that will get them to lift the body off the tires. As well the the mounting tabs have to be fabricated. With mounting holes placed by someone with a great deal of experience in doing them, and knowing how to take in consideration of the camber that changes dramatically as the car goes up and down. It isnt a backyard " I think I can do it" type of deal. You get one shot and these air collar strut kits are very expensive. I'm not saying for staying near stock height you cant use the old struts as a guide and get away with it. But If you want to lower, there is a very good chance when done, you dump the air out, lower the car, and dig the body right into the tires. Mine were done by someone who has done it for years and you can see in the pics below how close the car is to the tires in a hard turn. As the strut is lowered the camber forces the top of the tiire out very quickly. You have to get a good balance or either the body will hit the tire, or you will chop tires to shreds from the tire pointing in to far. Welding the tabs onto the strut bodies need to come from a trusted source with "Certified Welding" capabilities. It's your life hanging on these 2 /2 inch wide tabs welded to the strut body. And it's easy to burn the interior seals of the strut.

When done right, with the money and resources, the following pictures are possible.

The lowest Bonneville ever made, and sitting on 4 corner adjustable air.

Thanks for the info Archon and GXP. The rear sounds do-able and I would do a modified gas/oil shock or strut with the bags.

GXP what do you think of the assembly (and company) in the link below? They say its direct bolt-on for the front, but I don't see how it can be that simple. The assembly does include their version strut (and a huge cost). But if its true, it would probably pan-out with the cost of time/mod. labor/material/welding.

A concern is the tire clearance with the air strut base (not with the body because I am not using it to lower) as compared to the existing spring coil base-to-tire clearance on the existing stock strut (or also if I went with a bigger wheel). Its very close right now as it sets stock. Maybe 1.5 inch from strutbase to tire w/16in. wheels. I heard that the air strut base is much smaller in diameter and will not interfere with tire clearance, but it seems that can still be an issue because the plane of the tire travel as compared to the sharp angle the strut base sets (directly above the tire). Right now the stock strut base is at a sharp angle and this angle also allows for tire clearance--the base on the air strut shown below has no anlgle to its base.

And finally, the most critical question-- what is the possiblity/probability of an airbag blow-out if you hit a pot-hole on the highway at 70mph? And my visual of that one is not a good thing! Ok here is the link:

http://airbagit.com/product_info.php?products_id=3963
http://airbagit.com/popup_image.php?pID=3963

Thats a good company and I see they now make airstruts for some Bonne's too. But not the GXP. 3 years ago when I did mine there wasnt that many models to choose from. That price is standard pretty much across the board. Tire clearance should not be an issue with a premade kit. But as I said before, front airstruts are for lowering for the most part, or raising for a Donk. Either way they are way stiffer than OEM. The modern car airbags are modeled right off the ones used by semi trucks and very durable and DOT approved.

Ok, ok I gotcha now. Then my plan becomes to bag the back end, and for the front I will get some longer coils made and maybe some chunky thicky-thick spring isolators. Thank again.

BTW that Bonneville does look awesome, cool color too.