Good Setup for Wide Wheel/Tire Combo

I have been looking at doing 18x10.5 up front w/ 275s and 18x12s out back with 315 or 335s. From the measuring I have done I know they will physically fit, especially at a stock to close to stock height.

My question then becomes I think I can massage/cut enough to run this combo with a 3/5 drop.

Here is what I have been looking at suspension wise to achieve this.

98+ Blazer Stock Spindles(for C6 Z06 Brake Swap)
UB Machine Uppers w/ C10 Balljoints
Anyone have a recommendation on a lower for a coilover setup
QA1 Coilover, what spring rate for a 5.3 swap?

Out Back
3" Drop Springs
2" Block
QA1 Shocks

Now my only other option that I have considered is doing a full Ride Tech setup up front and out back. May consider doing a 4-link with Coilovers if I can achieve what I want without having to go air.

Truck will be daily driven and also been taken out for spirited drives and a couple track days

I'd suggest a tall lower ball joint as well.

I also steer most people away from the hybrid coilover style that QA1 has for our trucks.  The shock and the spring centers aren't lined up on our trucks and it causes all sorts of issues with that style of coilover.

My 2 suggestions:

1. Use stock springs, ZQ8 puts you in a good rate range at 590lbs. From my calculations in the past that gives a similar rate and ride frequency to a Corvette. 1.5" drop from springs and another 0.5" from the tall lower ball joint will give a total 2" drop.  Not quite your 3".   Add in a drop Blazer spindle? Or does that not work well with the Corvette braakes? It has been awhile since I really researched that, but I do know the Blazer drop spindles are $$$$.

Another stock spring option would be to take a lower rate spring and cut it to get the drop and rate you want.  That could take some experimentation, but would be able to use the stock lower control arm with improved bushings and the factory spring seat without the shock problems using the hybrid coil over design.  I have a list of some of the S10 spring rates.

If my memory serves me, Robert has also found a company or two that build custom rate stock style springs. Maybe he can chime in here too.

2. Cut up the spring pocket to use a traditional coil over.  I put some thoughts together in this thread:
http://www.pro-tourings10.com/index.php?topic=1587


Either route you take I'm shooting for 600lb springs on my Blazer with the 5.3 based on the calculations I did comparing wheel rates and ride frequencies on the Corvette.

More spring rate discussion here:
http://www.pro-tourings10.com/index.php?topic=1161

For a LCA for a coilover setup I prefer the old ART Strongarms that I have.  They're a nice clean design without anything hanging down below the structure of the arm.  I look at some of the newer arms with the spring/shock pocket and I cringe thinking about that hitting something on the road like a cement block... I have experience and I bought a new frame because of it.

I thought the c10 ball joint in the upper arm using the UB Machine arm was considered using the tall upper ball joint.

I don't have to exactly be 3/5 but want to get as low and wide as possible. I don't care about how stiff the ride is because I used to daily a few different hard tail motorcycles and a lowered C4 vette.

I would like to have a set of tubular upper and lowers so I will take a look at a few different options that are out there. Will g-body lowers work? I know there are a few different options if I'd go that route.

I run almost the exact same setup you're describing except for the wheel/tire combo. I use 17x9's with 275/40's.

I agree with Harley on the QA1's - if you're starting fresh, go with the ridetechs or a stock style spring setup. If you do go with the QA1's get the 650 lb springs (or 600's if they make them, I'm not sure they do). I have the 550's and could probably use them a bit stiffer for auto-x but those were the heaviest ones they offered at the time.

I would also avoid UB Machine. The arms are fine for the price but their customer service is awful. Budget a few months minimum to get your parts.

I have Spohn coilover LCAs and they work fine. The spring mounting pocket has started to bow on mine but I bottomed out my shocks a lot at some point while trying to find the proper spring rate.

The C10 upper joint is the same as a tall upper, but you do need a custom set of upper control arms to use it.  UB Machine is the only company I know that provides that.

I'm also suggesting a tall lower ball joint.  Actually the tall lower does more for ride height and handling than the upper.  The upper mainly gives the extra height between the ball joint pivots, which improves camber gain on our trucks, but on top of that the lower gives you a drop as well as improving the bumpsteer some.

I believe G Body arms kind of work, but the S10s use larger bolts at the frame.  Some bushings can be drilled out to the larger size, but other cases may require a new or custom set of bushings to work.  I do remember discussing using high end bushings designed for a G body at least once around here, but it has been awhile and I have no idea where to start looking.

I also want to mention that spring drops can only take you so far.  From my experience 3" typically puts you on the bump stops and I don't recommend anything above a 2" drop with springs.  There is just not enough travel as well as the fact that it starts to drive the roll center below ground, which tends to be detrimental to handling.  It isn't perfect, but the rule of thumb I typically use is keep the LCA (ball joint to frame mount) parallel to the ground at ride height.  There are other factors at play, but I'm not deep enough into ride theory to speak to it currently.

Well I have been looking at the RideTech stuff because I know most of the guys down there.

Looks like maybe a set of their Lowers w/ tall ball joints and a set of UB Machine uppers w/ C10 ball joints will fit the bill right. Using either their TQ Series Coilovers(seem to mount the correct way and a conventional style coilover), or using a QA1 and having to fabricate an upper mount.

I may just buy another frame and start from scratch and build up over time. Might also narrow the rear frame rails 2-3 inches to allow the wheels to sit inward a little more and run the 335 like I want. Would also allow only a small mini tub to be in the bed and to be somewhat lower to the ground.

Might also make it a little easier to stuff a 4-link w/ watts link or panhard bar and coilovers. Decisions decisions

I ran the Ridetech setup for a months, but ran into a number of issues and ended up returning it back to stock ZQ8 suspension. I am definitely a fan of stock style spring and shock setups. Something like a G-body lowering spring or Blazer Xtreme coils would net you about an inch of drop while maintaining a good spring rate (~600lb/in). You could combine that with with the Belltech Blazer drop spindles to get the 3" of drop you want.

If you're going to the effort of a complete frame build then I suggest this:



http://www.pro-touring.com/threads/37235-First-Gen-S10-Corner-Carver?p=992714#post992714

Like Ryo mentions in my other thread, moving the lower shock/spring mount out improves your motion ratio.

Only reason for suggesting a new frame is because it would be easier than taking my old one and trying to backhalf it in a weekend vs a couple of weeks. I love the adjustability of coilovers and air, but I almost wonder if you could run a ridetech front air setup and achieve the same performance as moving everything around to fitting a traditional coilover. I may be reaching here, but just not 100% sure.

I have setup back halfs before and they are pretty straight forward to me as long as I know what the vehicle is being used to. From reading that thread over on PT.net I can only assume we want to move the lower mount for the coilover out as far as possible and move the upper mount out as well to try and get a vertical setup.

This makes sense in the rear to me for wanting a vertical setup, but not so much in the front. Anyone care to explain a little more. I always thought you would want a 10-20 percent tilt to them to achieve best use of the shocks(not over or under using the shock for what it designed to).

i agree with what was said above, 3" on springs up front is way too low at stock geometry. I have some pics floating around somewhere when i did my first track day with 3" springs. significant body roll even with the 33mm bar. I overcompensated the next round, which i forget where i was height wise, but it was closer.

shocks, move them as far outboards as possible, with as vertical as possible. you want the closest to 1:1 motion ratio you can get, which is difficult in itself for a stick axle. especially in 1 wheel bump.