Coilovers!!

TheBac

Why do I keep doing this?
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Apr 19, 2008
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Thank you for all the information, Luke! I will shoot Jon an email when the time comes for suspension work.
 

408.Luke

Joined the DARKSIDE
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Well I have some good news about a direct bolt in kit for the Duramax, I have a set of ridetech's coilovers on the way for testing. I probably wont get to put them on the truck until the beginning of April and hopefully by the beginning of May testing will be done and the kit will be available. If this kit works out it will be 100% streetable/daily driveable and will be able to tow and do everything a stock truck should be able to do. My truck is being setup up quite low, however to get the low stance we will be using 2" drop spindles. With stock spindles and my "33 in" micky ATZ's ride hight will be around 37 1/2" and 25 1/2" with the drop spindles, this way the kit will be useful to a lot of people.

Some info on the kit, Ridetech single adjustable shocks, 1150lb hyperco springs (12" I think but maybe 10" cant remember what it ended up being), Direct bolt in with no need for a top stud adapter, and no extra parts needed. Kit cost from what i can tell shouldn't cost to much more than the QA1 setup most are running (can anyone tell me what they are paying for the QA1's?) However we will be welding up the upper shock mount and will suggest this for anyone buying the kit.


Front Ride hight w/ 2" drop spindles 25 1/2" from ground to fender in the center of the wheel.

IMG_0103_zpsb70fe14e.jpg


IMG_0101_zps00a9b0b7.jpg
 

TheBac

Why do I keep doing this?
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Apr 19, 2008
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Bringing this back up to ask for advice.

With a 14" extended, 10" compressed height shock, what length spring should I be looking for? Is 10" optimal? Will 8" work ok as long as the block height is 4" or more? Ideas on weight rating? Ideas on manufacturer? Ive been looking online for a while now.

Im looking at the QA1 DS402 shocks. Have to use the urethane bushing model due to their requirements for adding the lower T-bar mount.

Thanks for any help.


BTW, I found a 12", 1000# spring if you're interested: http://www.racingsprings.com/12 inches tall/PAC-12x2.5x1000/item/111
 

408.Luke

Joined the DARKSIDE
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Bringing this back up to ask for advice.

With a 14" extended, 10" compressed height shock, what length spring should I be looking for? Is 10" optimal? Will 8" work ok as long as the block height is 4" or more? Ideas on weight rating? Ideas on manufacturer? Ive been looking online for a while now.

Im looking at the QA1 DS402 shocks. Have to use the urethane bushing model due to their requirements for adding the lower T-bar mount.

Thanks for any help.


BTW, I found a 12", 1000# spring if you're interested: http://www.racingsprings.com/12 inches tall/PAC-12x2.5x1000/item/111


Is this for the 1500? You will probably want a 8", thats what we run on pretty much everything. Id guess ~800 on spring rate but that all depends on weight and where the coilover is mounted. I would avoid QA1's, all the ones ive seen leak.
 

Chevy1925

don't know sh!t about IFS
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Oct 21, 2009
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Bringing this back up to ask for advice.

With a 14" extended, 10" compressed height shock, what length spring should I be looking for? Is 10" optimal? Will 8" work ok as long as the block height is 4" or more? Ideas on weight rating? Ideas on manufacturer? Ive been looking online for a while now.

Im looking at the QA1 DS402 shocks. Have to use the urethane bushing model due to their requirements for adding the lower T-bar mount.

Thanks for any help.


BTW, I found a 12", 1000# spring if you're interested: http://www.racingsprings.com/12 inches tall/PAC-12x2.5x1000/item/111

Minimum you want half the shock stroke for spring height to keep you out of trouble. You ought to be able to get away with a 12" spring as well Tom. I'm running 2 7" tall springs on a 6" stroke shock with a 1/2" tall guide in between the two springs since its setup for dual rate and could fit a 16" tall spring if I wanted.

What is the weight your looking at on the front end? Where do you want the ride height to be? Since your running a 4" stroke shock your either Gunna have to limit up travel or down travel of the suspension, that will help determined ride height as well
 

TheBac

Why do I keep doing this?
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Apr 19, 2008
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Is this for the 1500? You will probably want a 8", thats what we run on pretty much everything. Id guess ~800 on spring rate but that all depends on weight and where the coilover is mounted. I would avoid QA1's, all the ones ive seen leak.

Minimum you want half the shock stroke for spring height to keep you out of trouble. You ought to be able to get away with a 12" spring as well Tom. I'm running 2 7" tall springs on a 6" stroke shock with a 1/2" tall guide in between the two springs since its setup for dual rate and could fit a 16" tall spring if I wanted.

What is the weight your looking at on the front end? Where do you want the ride height to be? Since your running a 4" stroke shock your either Gunna have to limit up travel or down travel of the suspension, that will help determined ride height as well

:doh: Yes, its for the 1/2 ton. I think around 1500lbs per front corner, but it could be less. I figured at least a 900# spring, 8" long.
Coilover would be mounted in place of the stock spring/shock like most people do.
I have no idea how to figure out ride height right now, since the body is off the frame, but hoping for the top of the 265 tire to be right even with the top of the wheel well when its done.

James, a 12" spring on a 14" fully-extended shock? Are you sure? Wouldnt the coils be almost in a bind situation with a spring that long on a shock that short?

Ive got to email the guy at DB what he thinks. Maybe Id be better off using the stock suspension for the time being, and wait until the truck is road-worthy to figure out the proper coilover.
 

Chevy1925

don't know sh!t about IFS
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Oct 21, 2009
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Oh yeah. It would mean you can preload that coil at least 2". It works the opposite of what your thinking. A 8" coil will have a block height at 3.75" or more depending on spring rate. That means that you won't be able to hardly put any preload into it without getting coil bind at full shock compression.

Take the spring out of the front end, throw a fender on, throw a tire on and jack that front arm up to where you want ride height. Measure from the frame mounting point to the LCA mounting point and add in a 1/2" if your using the stem to eye adaptor and write it down. Then fully compress the suspension and re measure in the same spot and write it down. And also a measurement of the tire to fender gap at ride height and at a theoretical full drop of the suspension of the shock extended out (basically take measure from where i was telling yoh before for the shock measurements, drop the suspension till it hits 14", then measure your tire to fender gap) Give me these measurements and ill tell you based on weight what spring and how much preload is needed.
 

Chevy1925

don't know sh!t about IFS
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Oct 21, 2009
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Ill pm you my number Tom so if/when you really wanna dive into it, ill walk ya through the whole setup and get ya figured out. Once you see what I'm talking about, it's easy to understand. Just takes a bit of math.
 

408.Luke

Joined the DARKSIDE
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:doh: Yes, its for the 1/2 ton. I think around 1500lbs per front corner, but it could be less. I figured at least a 900# spring, 8" long.
Coilover would be mounted in place of the stock spring/shock like most people do.
I have no idea how to figure out ride height right now, since the body is off the frame, but hoping for the top of the 265 tire to be right even with the top of the wheel well when its done.

James, a 12" spring on a 14" fully-extended shock? Are you sure? Wouldnt the coils be almost in a bind situation with a spring that long on a shock that short?

Ive got to email the guy at DB what he thinks. Maybe Id be better off using the stock suspension for the time being, and wait until the truck is road-worthy to figure out the proper coilover.

your probably going to find that a 14" fully extended shock will be to long, the ones on my duramax are a 15" fully extended and your talking about a 1/2 with smaller bits and pieces. Im running a 8" spring on the duramax with a 4" stroke shock and im no where near coil bind, and I have zero preload on the coil. What you are going to run into with a 12" or even possibly a 10" coil is its going to be very difficult to get on shock because it will need preload. Most of what we are running doesn't take a lot of preload if we have hit the right spring rate. This is probably the best picture of the ridetech 1500 setup that I have. It's a 8" spring on I think a 3" travel shock but could be 4". you can see it has plenty of adjustment both ways.






It will probably be best to wait until you have the motor in and the fenders on to set ride hight. Once all of thats done pull the springs out of the front and use jacks to get the truck to sit where you want it. Then measure from the underside of the upper mounting plate to the center of the lower shock mount plate. This measurement will be shock length at ride hight obviously. Im running about 60% compressed but you probably want to shoot for more like 40% or 50%. So if you get 10.5" and you run a 3" shock your looking at 12 extended and 9 compressed. You are going to lose a lot of wheel travel (especially on the extension side of things) but it doesn't matter for a street truck. On the spring rate it may take 900 and it may take a few trys to get it right without corner weighting it. There are calculators where you put in all the Shock distance measurements and corner weight and will spit out a decently close spring rate.

here is mine fully extended, goal was 14" at ride hight but i decided that wasn't low enough, hence why im at ~60% compression. I may step up another 100lbs on the spring rate to get a bit stiffer ride that im looking for, but would have to get a shorter shock to have the spring under minimal rest tension and keep my current ride hight so Kinda on the fence about it.

 

GeneralTJI

Turbo Todd
Jun 1, 2010
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Check your mounts now and then!! I had to pull my coils, and go back to bars. The lower mount gets its a$$ kicked. Bent that bolt on each side and was chewing through it because it destroyed the bearings in the ends of the shocks (busted them up after wearing out the spacers). Im not too sad because I needed to raise my front end back up a little - bad wear on my tires.... But just mentioning it... Keep an eye on everything
 

408.Luke

Joined the DARKSIDE
Sep 19, 2009
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Check your mounts now and then!! I had to pull my coils, and go back to bars. The lower mount gets its a$$ kicked. Bent that bolt on each side and was chewing through it because it destroyed the bearings in the ends of the shocks (busted them up after wearing out the spacers). Im not too sad because I needed to raise my front end back up a little - bad wear on my tires.... But just mentioning it... Keep an eye on everything

:thumb: Thanks for the info! i have been keeping an eye on them, but i don't think i will have as big of a problem as you have had. I put in some bigger bolts for the coilovers than what was through the stock shock. We haven't had any problems with the bearing mount on the ridetechs, but then again we haven't had anything this big on them.
 

hondarider552

Getting faster
May 28, 2008
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James, I need coilovers on the single cab.... :happy2:

Only a year late, Measured the OEM crap and James put together a list of shit to buy. I run stock keys all the way down. Nothing fancy as far as lowered.



http://www.summitracing.com/parts/eib-12002500900s

http://www.summitracing.com/parts/hal-dd501

http://www.amazon.com/gp/product/B005TTZIH2/ref=oh_details_o01_s00_i00

http://www.amazon.com/JEGS-Performa...spell&keywords=Coilover+spanner+wrenchfor+QA1

My front end weight currently is 3,480lbs with 2,020lbs on the rear. From what everyone says about the weight of the Tbar group, front end should be less than 3400lbs once done.
 
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Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
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There is a reason we went with the longer shock as well, no mistake there incase anyone is wondering ;)

Sent from my iPhone using Tapatalk
 

PACougar

Active member
Jun 27, 2012
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El Dorado Hills, Ca
Only a year late, Measured the OEM crap and James put together a list of shit to buy. I run stock keys all the way down. Nothing fancy as far as lowered.



http://www.summitracing.com/parts/eib-12002500900s

http://www.summitracing.com/parts/hal-dd501

http://www.amazon.com/gp/product/B005TTZIH2/ref=oh_details_o01_s00_i00

http://www.amazon.com/JEGS-Performa...spell&keywords=Coilover+spanner+wrenchfor+QA1

My front end weight currently is 3,480lbs with 2,020lbs on the rear. From what everyone says about the weight of the Tbar group, front end should be less than 3400lbs once done.

Finally getting on team coilover:D