Coil Over Spring Rate (truck Weight Front And Back)

[silverblaz]

OK i have searched this for a good week before posting trying to look back and see if anything has been said and i have found a few things but nothing for sure.

I am going to do coil overs front and back on my SYTY powered blazer ( 2wd) QA1 makes a bolt in kit for the front but i need to figure out the weight of the FRONT of the truck for the spring rate because everyone i have talked to said the 300 lb springs are to light???? i dont know this for sure but its not just for drag i will be driving it alot.

Now has anyone weighed the front and back of there trucks or ever do coil overs in the rear and know the spring rate used.

I have read the kits that used the mono leaf to center the axel then the coil overs in the rear but would the spring rate be different because of the leaf in there??? hmmm alot of questions but if i dont ask i will never know

 

[dgoodhue]

Re: Coil Over Spring Rate (truck Weight Front And Back)

300# is really light. As the spring is compressed the rate will go up. A smaller spring rate will need to be really compressed. The PEP coilover used a 450# spring and you really need to compress the spring quite a bit to get anywhere close to a reasonable ride height, I have 600# springs with a set of tubular a-arms. I think Jeff Scott uses a 750# spring on his TTV8 Typhoon.

 

[canadian]

Re: Coil Over Spring Rate (truck Weight Front And Back)

See if you can stop by one of the weigh stations along the QEW and park the front of the Blazer on the scale and see what it says.

 

[silverblaz]

Re: Coil Over Spring Rate (truck Weight Front And Back)

OK i did the total weight with me in the truck last week and it was

3600lb TOTAL

Then i tried pulling the front on then the back on yesterday (half tank of gas not full this time)

FRONT was 1940lbs

REAR was 1640lbs

TOTAL was 3580lbs so DAMN close if i do say so myself

 

[Loeryder]

Re: Coil Over Spring Rate (truck Weight Front And Back)

Sounds like your weight is similar to that of a SyTy.

I just bought a brand new SyTy specific kit and it came with 550# springs recommended.

300 is way too light for how heavy your ride is.

If you like it stiff I would try the 600# but I wouldn't stray too far from 550 - 600 without consulting a Suspension Tech.

 

[rodent]

Re: Coil Over Spring Rate (truck Weight Front And Back)

I have the 600# springs on my RPM kit and I think they're way too stiff. Looking for softer springs...

 

[fivetodrive]

Re: Coil Over Spring Rate (truck Weight Front And Back)

What are the lenghts of the springs? I have a set of penske coilovers that I will be putting on crispy... Someday...

 

[dgoodhue]

Re: Coil Over Spring Rate (truck Weight Front And Back)

What are the lenghts of the springs? I have a set of penske coilovers that I will be putting on crispy... Someday...

The length of the spring, how compressed the spring will be install make a big difference. One of the big difference in JS and RPM Coilovers (beside the ball joint angle) is the mounting point of the coilover shock. JS is about 1" higher than RPM. So the common QA! shock with Hypercoil 600# spring will need to be compressed quite a bit less than on the JS suspsnesion vs RPM's.

 

[Daveman2]

Re: Coil Over Spring Rate (truck Weight Front And Back)

300# is really light. As the spring is compressed the rate will go up. A smaller spring rate will need to be really compressed. The PEP coilover used a 450# spring and you really need to compress the spring quite a bit to get anywhere close to a reasonable ride height, I have 600# springs with a set of tubular a-arms. I think Jeff Scott uses a 750# spring on his TTV8 Typhoon.

This is completely true, I have 450s on my ex-4WD blazer that's probably about 3200-3400lbs and they're comfortable but too light for the time being and too low as mentioned, but I'm looking to get weight near 3000 and relocate stuff like the battery to the rear, so they should work well for me then, 300s would probably make your blazer sit super low, I have to crank mine alot to get to proper suspension geometry.
I'd say something like 525 would be nice if

 

[jpalmer]

Re: Coil Over Spring Rate (truck Weight Front And Back)

the ones i had for my 2wd were 500# and then i went to 450# and liked it better, but it was lifted so i would guess 500# is pretty close

 

[fivetodrive]

Re: Coil Over Spring Rate (truck Weight Front And Back)

The length of the spring, how compressed the spring will be install make a big difference. One of the big difference in JS and RPM Coilovers (beside the ball joint angle) is the mounting point of the coilover shock. JS is about 1" higher than RPM. So the common QA! shock with Hypercoil 600# spring will need to be compressed quite a bit less than on the JS suspsnesion vs RPM's.

For now I would be putting them on stock A-Arms. I couldn't pass on the penske coil over's since I got them for a great price and they are a great shock. So what length spring would give me the best fit for the stock arms?

 

[silverblaz]

Re: Coil Over Spring Rate (truck Weight Front And Back)

Well put the coil overs in this weekend WORK GREAT 450lb spring rate and its perfect for the truck only thing to do now is adjust ride hight a little bit and dial in the adjust ment on the shock a little more to see what changes

 

[fivetodrive]

Re: Coil Over Spring Rate (truck Weight Front And Back)

So did you use a 10" spring?

 

[JSM]

Re: Coil Over Spring Rate (truck Weight Front And Back)

I see you ran 450's front.

For comparison, my 4k lb truck I use 750 front, 300 rear (going from memory on rear). Might do 650lb in front if I get bored to try.

 

[Daveman2]

Re: Coil Over Spring Rate (truck Weight Front And Back)

I see you ran 450's front.

For comparison, my 4k lb truck I use 750 front, 300 rear (going from memory on rear). Might do 650lb in front if I get bored to try.

yeah light blazers like the 450 I guess, I have 250s out back and it feels pretty balanced right now.

 

[silverblaz]

Re: Coil Over Spring Rate (truck Weight Front And Back)

daveman with the 250 lbs in the back how is the truck on choppy roads? is it really bouncy and do you have a 4 link? 5 link what set up you running

i am going to be running a parallel 4 link with pan hard

 

[Trapper]

Re: Coil Over Spring Rate (truck Weight Front And Back)

Silvrblazr any pics of your coil set up on the front?

 

[Daveman2]

Re: Coil Over Spring Rate (truck Weight Front And Back)

daveman with the 250 lbs in the back how is the truck on choppy roads? is it really bouncy and do you have a 4 link? 5 link what set up you running

i am going to be running a parallel 4 link with pan hard

Sadly for now only fiberglass leafs. I want to run a 4-link at some point with a pan hard, but don't have anywhere near the amount of $$$$ I'd need for that right now.

It is surprisingly comfy, but my car is pretty raked and there's virtually no weight in the back (no rear seats or spare) so sometimes it does get a little bouncy in the rear. I'm also running crap shocks out back for the moment so that doesnt help.

They ride MUCH MUCH softer than my old belltech springs did, you just don't notice bumps in the road as much, and the wheels stay on the ground really well.

I'm doing a battery relocation soon after I fix my wrecked front end, and leveling out the ride so Ill have a better picture of the spring balance then. If you want to see how my springs handled in the auto-X I have videos in my thread under brick racing.

 

[silverblaz]

Re: Coil Over Spring Rate (truck Weight Front And Back)

Trapper my truck is a 2wd not 4x4 but i can get you pics if you want let me know?

I will be doing a 4 link with pan hard over the winter need to pay off some things just got bought an 09 matrix as an every day car so gotta save up.

When i do my 4 link i will post pics as i do it so you can see, the main Pain in the ass is going to be remove the stock ( shock mount, gastank) crossmember and putting in a new square tubing one to mount the coilovers to and re mount the gastank as well. well removing it wont be bad actually a saws all should take care of it .... i still need to get a plasma cutter for the shop.

 

[jstblz]

Re: Coil Over Spring Rate (truck Weight Front And Back)

im running 600# in front, but I also have a 4x4 with a v8 in a 2nd gen blazer.