I know that there are VERY few real upgrades available to the '99 H-bods... but since I am swapping a tranny in the next few weeks... I figured I'd ask.

I see various members are having bad things happen with their subframe bushings. Since I live in a rust prone area, and I need to remove at least one bushing, I figured the others may soon follow. It seems to me that the bushings are a dealer-only item. Are there any subframe bushings out there that fit a '99 Bonneville SLE that will firm up things. I assume the originals are rubber. Do H and W body bushings interchange at all? I know they are different in number. Would, say, bushings from a GTP Comp G be a upgrade (assuming they fit...)?

Next, I'm curious about front springs/struts. What is the best upgrade available for them? I feel my springs are likely tired, as the car is sitting much lower that when it was nearly new. I like the lower height... but not bottoming out. I'd rather not cut new springs. Any of the strut offerings out there worthwhile?

I don't mine some minor tweaking to get stuff to work, if the payback is there... as long as any mods are reasonably safe.

The rear setup is going to have to wait... its out of my budget for now.

Thanks in advance.

BKNJ

www.coilsprings.com will make a set of one off drop springs for you.
Energy suspension makes a front endlink kit.

If you do get springs don't go past 1.5". I did 2" and factory replacement shocks could not keep up.

I found out that you can run W-body front shocks/springs with 00+ Bonneville knuckles. More info here:
http://95nasta.infiniteboost.com/wp-...grade_1pt1.pdf

I added drag bags to the rear to keep it from smacking the ground everytime I smacked the throttle. Did urethane endlinks and center bushings on the front and rear sways to stiffen them a bit.

95NA kinda owns the universe on dropping though. He did a serious drop.

Lots of polyurethane lol

Hi, I just wanted to know if you knew if the W-body shock conversion would work on the 00 up Bonne'*, if your using the knuckles from them anyway?

You need to modify the shock mount. Check out 95'* link it'* all there.

I read the whole thing and if I already have an 00 up car, do I need to change the calipers to F-body for this to work or is that just an added bonus?

I have an 01 Bonne that I would like to do your W conversion to. If I am understanding this all correctly, since I already have the proper year knuckles, all I would need to do is get the W strut and spring, and it says that the top of the H and W spring has the same size coil so theoretically i would be able to use my stock mount with some tweaking for the diameter of the piston size. If the 99 had the same spring as 00 up of course. But my main confusion is your spring itself, it said that you used a spring that would have lowered a W car 2 inches , but that your car lowered 3? Is that because of the swap or is that because you used used parts? I just want to make sure I got this right. I'm scared if I buy the W spring that says a set drop I don't want it to end up being an inch more and having it rub. So thank you in advance and it was an excellent write up about the conversion. Its nice to have some mods we can do to Bonne'* other than engine once in a while. Thanks again

I just wanted to clarify this is only for the front.

As long as the top inside diameter of the 00+ and the 92-99 H body springs are the same, GP strut mod will work. But, I'm unsure of the 00+ strut shaft diameter, so you maybe on your own for the correct shim.
The easiest way to confirm the spring ID is to hit up a wrecker or autoparts store.

I'm going to have to assume that a drop on the 00+ will be even more than a 92-99 due to the added weight. The 92-99 H weighs a few hundred more lbs than the 97-03 W, and that'* where the extra drop came from in my case.

I would suggest getting very minimal GP drop springs for an 00+. You're not going to know for sure what the drop is until you bolt it all up.

Which is all fine and dandy, provided you can find it. IIRC, the only thing polyurethane clearly available for the H-bodies is sway bar bushings.

However... it appears that Energy Suspensions has cab body bushings for *-10 based Blazers. SteveX used these polyurethane bushings for his subframe bushings.

I'd really like to try this... but I'm unclear of the sizes of the subframe bushings in the H-bods. Are all 6 subframe bushings functionally the same? I see a lot of posts showing different GM part numbers for each bushing. Anyone know about this?

After looking over the Energy Suspensions catalog really closely, I suppose one could use the generic parts to piece together a polyurethane kit for the control arms... if one had measurements for the stock pieces.

BKNJ