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Front Suspension Thread & NBS kit discussion

105K views 138 replies 36 participants last post by  HackMcMASTER  
#1 · (Edited)
First up is the proper design of a control arm suspension. The upper arm will be shorter than the lower arm and the distance between upper arm and lower arm frame mounts will be shorter than the upper and lower ball joints. This will keep instant center for each wheel on the opposite side of the wheel. this way your roll center will be a few inchs off the ground.
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if you begin to raise the upper arms to eliminate camber, you will cause bad geometry and have a terrible handling truck even if lowered. You can raise the arms until you get close to the point of being parallel. once that happens the instant center becomes so far away from the vehicle that it is virtually nonexistant and the roll center raises causing more body roll.
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If you raise the arms too high, where the distance between the upper and lower arm frame mounts is greater than the upper and lower ball joint distance, you cause the CG to be higher and the instant center for each side to be on the same side. this puts the roll center below the ground causing the truck to seem very top heavy even though it is lowered. The higher the arms are lifted, the more severe the handling will be.
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It is also very important that the upper and lower arms are NOT even length. This keeps the load bearing tire from rolling as much as the body does when turning. For example, a proper, uneven length arm setup will allow the load bearing tire to move only 2* while the body may roll 5-6*. This will give much more even tire wear as well as give much better traction while turning.

These are MY OPINIONS on front suspension setup's for the NBS trucks. reason I emphasize my opinion is because I don't want to have a bunch of arguing about me being right/wrong about them.

I will start with the ones I am most farmiliar with
All of these kits require the spindle to be reamed for the lower ball joint to come through the bottom

Distinct Fabrications
Hector's kit is very reasonably priced. Track width is narrowed 2" and is designed to lay on 24's with stock spindles and stock upper arms. adding Belltech 2508 drop spindle will allow 295/30/26 or 275/25/28. the kit flips the lower ball joint, comes with Heim steering, and tabs to raise the upper arm. its much more reasonably priced compared to all the other kits. I just got his lower arms and the tabs because i already had the heim steering. i love the quality. the down side is you have to do a lot of measuring and weld all the tabs on individually. you can buy the kit with or without shocks, and also with or without matching upper arms
this is an easy way to contact him or I can pm you his phone number.
http://www.facebook.com/distinctfabrications

Ekstensive Kit
This is by far the easiest kit to install and comes with everything you want. again 24's on stock spindles and 26's and 28's on 2508's. upper and lower arms, heim steering, shocks, and bracket. The bracket has all the tabs welded on and is very simple to install. the track width is narrowed 3" with this kit. It is a little more pricey at $1100, but for a good product with very simple fabrication skills needed, this is the way to go.
https://www.ekstensive.com/store/pr..._info.php?cPath=38_144_48_158&products_id=287&osCsid=s09sc9udedkvosqnlu90gi8p71

MMW (Michigan Metal Works)
With the Jeebus Joint upper joint and flat plate arms, the MMW kit is a very nice kit to look at. 24's on stock spindles and 26's and 28's on the 2508's. The Jeebus Joint allows you more articulation than the standard ball joint and you don't have to worry about greasing or busting boots. Like the Distinct Fab kit, you have to weld on all the upper tabs on individually. So the fabrication skill set is a tad bit higher. Also the lower ball joint is moved foward almost 1", so measuring with the lower arm and spindle installed is recommended. This kit is a little over priced at $1200 since you get no shocks or steering components like the distinct fab and ekstensive kits provide. This kit narrows the track width 1.5"
http://michiganmetalworks.com/store/index.php?route=product/product&path=60_65&product_id=103

Choppin Block
This kit was being priced at $1600 last time i checked with them. From what I can tell, they are nothing special. its about a copy of the Ekstensive kit, the only difference is you are suppose to get spindles as well for that price. here's their site for contact information
http://www.choppin-block.com/contact.html

Control Arm options using stock mounting points.

Stock arms with flipped uppers and McGaughy 16” drop spindles are a cheap and effective front setup as long as the wheel and tire combo isn’t very large. 29” is the biggest I would go on a set up like this. This keeps all you suspension geometry intact and working properly.

RideTech Strong Arms (ART arms)
ART arms are designed to keep extremely good geometry at lower ride heights. The track width is narrowed ~1”. The ball joint angles have been tweaked a little to provide better movement without binding up in the cycle they are designed to work in. which is not laying out. These arms will be an improvement over stock arms and they will provide a nice advantage if you use the McG 16” spindle. Of course on these arms, you will not be able to use the spacer to get full 2” of drop out of them. This is still a big help to those wanting the best overall suspension geometry while laying. Going with a set of these for your 22’s would be perfect. Going bigger than that will cause a little more camber than desired but as long as you’re keep your set ride height in mind when driving, tire wear shouldn’t be an issue. At $1000 they may seem pricey but that’s about the norm for a good quality set. You get no shocks or shock tabs with these
http://www.ridetech.com/store/trucks/?subcats=Y&features_hash=V287.V32

MMW budget arms
Like the front kit, the budget arms are also flat plate arms. These arms are very good for 29” wheel and tire combos. The advantage over the Strong Arms is mostly just price. At $700 (raw) or $800 (pc’d) they are cheapest of the straight bolt in arms that are worth anything. You get no shocks or shock mounts with these arms
http://michiganmetalworks.com/store/index.php?route=product/product&path=60_65&product_id=112

KP Components LayArms
KP Components is now offering front suspension setups for trucks to get the front laying as well. These arms are good quality arms. I recently got to look at the actual NBS set of arms since the website doesn’t show the actual picture. The arms look quality and they offer a bunch of different options for their setup. You can order it with/without bags, with/without sway bar, with/without drop spindles, and you can upgrade the standard shocks to single or double adjustable Varishocks. The only down side to the kit is price. The basic kit which has arms, bag cups, shock mounts and shocks is a whopping $1229. That’s extremely high for something that isn’t going to be much better than any other set of arms.
http://www.kplinks.com/product.php?productid=384&cat=104&page=1

Now I’m going to move on to the companies that sell their arms on the slogan “lay out on 24’s”. this statement is the most misleading statement there is. You can lay the truck on 24’s on factory arms. If all you are concerned about is the way your truck looks laid out, I.E. show truck, just build some long uppers and be done. Don’t expect anything else out the truck but to look good laid out though.

Choppin Block
These arms have a reputation that has followed them since they came out. Ask anyone that’s used them and they will give the phrase, “they’re pretty much a tubular factory arms”. You get no narrowed track width to help tuck the wheels and from my emailing with them, they aren’t the best at customer service. Again $800 is cheaper than most arms, but I would spend a little extra money and get a better set of arms.
http://www.avsontheweb.com/product.php?productid=738&cat=478&page=1

Cando Specialties
These arms aren’t talked about as much. They are a nice looking arm, but the upper and lower ball joint seems to be tweaked way too much. It will give you better camber laid out but will hurt the truck once you begin to lift it. The big downside is the $1000 price tag. For just a set of raw metal arms, that’s too high.
http://www.candospecialties.com/

Now for my final company report

Dallas Hotrod Parts
DO NOT BUY FROM HIM!!!!! Previously Barnyard Customs, Mike has no need in building arms to be sold over the internet. His welding looks good, but he messed up my arms and a couple others as well
 
#7 ·
I see brett
I had BS with my old beltech 17+ while i was static,and had a good amount of NC,if i didnt bag i would have swapped spindels a long time ago,but sold those and on stockers now,talk about the best damn spindels ive ever owned :)
yeah, but you went passed the point they are designed to work. 4" drop is the lowest the spindle is designed around. you'll have bumpsteer with anything setup thats cambered. the McG 16" would be the only spindle you could have went to, to cut down the bumpsteer.
 
#8 ·
Ok. I have a 03 nbs. Chopping block uppers, stock lowers, bag cups ,re7 . with 265/40/22 . 16 inch spindles. What exactly would I need to do to decrease camber when laid out? Raise uppers? Do I need to shorten the lowers or replace? Thanks for all your info!

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#9 ·
Ok. I have a 03 nbs. Chopping block uppers, stock lowers, bag cups ,re7 . with 265/40/22 . 16 inch spindles. What exactly would I need to do to decrease camber when laid out? Raise uppers? Do I need to shorten the lowers or replace? Thanks for all your info!
that tire size is causing a ton of the camber for you. if thats the tire size you plan to run, then you will want to go back to shorten the lowers 1/2" and see what that gives you. I advise you to step down in tire size and not mess with moving your mounts or shortening your arms for 22's.

If you plan to step up to 24's, then you probably need to just deal with it until you get 24's and redo the front suspension all together with one of the kits I listed above.
 
#10 ·
the ekmw kit uses stock spindles for every wheel
 
#11 ·
No one said you can't use stock spindles for 26's or 28's. but you won't have the same suspension geometry though out every wheel with the same spindle.

Using the drop spindle creates better geometry for the larger wheel while allowing you to stay in the same series tire as you jump sizes. Instead of running a 275/25/26.
 
#12 ·
Thanks for the input. I had 265 35 40 series tires and the ride was terrible. I also didn't like how little they looked in the wheelwell. So just shorten the lowers and not move the uppers at all? I want to run the 22's. I like the rubber for the ride quality. Thanks again!

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#13 ·
Thanks for the input. I had 265 35 40 series tires and the ride was terrible. I also didn't like how little they looked in the wheelwell. So just shorten the lowers and not move the uppers at all? I want to run the 22's. I like the rubber for the ride quality. Thanks again!

Sent from my SPH-D710 using Tapatalk 2
yeah, shorten the stock lowers no more than 1/2". if that doesn't get you were you want to be, then you'll need to raise the uppers, but depending on the spindle, it will be a different amount
 
#19 ·
yeah, but you went passed the point they are designed to work. 4" drop is the lowest the spindle is designed around. you'll have bumpsteer with anything setup thats cambered. the McG 16" would be the only spindle you could have went to, to cut down the bumpsteer.
Just wondering my truck has pretty bad bump steer when riding low and i have the 17"+ spindles. If i switched it to 16" spindles would that help wit the bump steer? And will there be any adverse effects of switching?

Also what is the advantage of running Heims on the steering?

Thanks
 
#20 ·
Just wondering my truck has pretty bad bump steer when riding low and i have the 17"+ spindles. If i switched it to 16" spindles would that help wit the bump steer? And will there be any adverse effects of switching?

Also what is the advantage of running Heims on the steering?

Thanks
you will loose a little bumpsteer.

heims don't need greasing, have more articulation, and are tighter than traditional ball joints.
 
#22 ·
#23 ·
hey Brett, have the KP front kit, Belltech spindles with 24" rims( HELO HE866 24.00" x 9.50"+35) running 295/30R24 tires. I have a lot of camber. How do I fix it?
 
#24 ·
Front Suspension Thread & NBS kit discussion

hey Brett, have the KP front kit, Belltech spindles with 24" rims( HELO HE866 24.00" x 9.50"+35) running 295/30R24 tires. I have a lot of camber. How do I fix it?
If you want a good front suspension then you have to Redo the entire front suspension. The kp kit isn't any better geometry than stock arms, and the belltech spindle isn't good for bagged vehicles either.

I tried to tell you all that back before you built the truck.
 
#25 ·
Re: Front Suspension Thread & NBS kit discussion

If you want a good front suspension then you have to Redo the entire front suspension. The kp kit isn't any better geometry than stock arms, and the belltech spindle isn't good for bagged vehicles either.

I tried to tell you all that back before you built the truck.
They were free parts, I spent nothing on them.
Since I am goiong to need to start over what is the best to buy, or can my KP arms be modified to fix the problem?
Why are belltech spindles (99-06 GM 1/2 Ton 00-06 Tahoe/Suburban/Avalanche 2" Drop Spindle Part #: 2508)not good for bagged trucks?
 
#26 ·
Re: Front Suspension Thread & NBS kit discussion

They were free parts, I spent nothing on them.
Since I am goiong to need to start over what is the best to buy, or can my KP arms be modified to fix the problem?
Why are belltech spindles (99-06 GM 1/2 Ton 00-06 Tahoe/Suburban/Avalanche 2" Drop Spindle Part #: 2508)not good for bagged trucks?
I understand they were free but the arms don't do much for you except look good.
And no, the belltech 2508 spindles are not good for bagged trucks unless you build the front suspenion for the spindles. the spindles are 1.25" taller than stock and the taller the spindle to worse the camber curve will be if you do not alter the front suspension mounting points.

the only way you're going to fix the camber, with the arms you have, is to make new upper control arm mounts. If you want to really build a nice front suspension, you need to get the lower arms modified to have the lower ball joint to come through the bottom of the spindle and make new upper mounts. then go to hiem steering.

you will have to do this one off if you want to use the arms you have.