The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 08-27-2013, 12:07 AM   #1
chevybuilder18
Registered User
 
chevybuilder18's Avatar
 
Join Date: Mar 2012
Location: Lincoln, IL
Posts: 880
cutting coils, offsets tie rods?

I've drove my truck a couple times after i lowered it and it sucks on handling. i did cut 1 1/4 coils off so i can drop the front 2 inch's and a half. however i noticed this strange tire squeal going down the road, ever time i accelerated, i would swerve just a hair without losing control. even if i managed that, getting the truck to go over hills was hard especially accelerating to 60... its scary. but my theory is the tie rods are pushed out, and take more abuse on this set up. i have not been driving it, ever since i dropped the LM7 in it, lack of a power steering and alternator on the engine. i didnt figure parts like these wouldnt be laying around. especially after 11 years since the vehicles fitted with these engines could have been wrecked... but anyways the thing is i believe i may be able to fix the short cuts we make to save money and time on new lowering springs. the new tolerances on each cut individual coil has changed. hence the load capacity has dropped. if you have cut your coils and not satisfied with handling, this is why. another factor, is the heat you put on them to cut them, of coarse i made sure mine were cool through the whole thing so it wouldnt take strengths away. i have a remedy that may fix this. since load capacity has changed, and there a lil weaker, the springs are bouncing more, causing the ride height to change in the front but not the back. since this happens, the tie rods are pushed and pulled by the height change. I've noticed this, since our trucks rear leafs and axles aren't independent or as heavy as the front. to balance this, there's coil stiffeners out there on the shelf at autozone, aka coil spacers. these spacers are my tactic to try and stiffen the ride, not only that, but better than factory shocks are going to be needed so will an entirely new way of balancing the tie rods.. any one ever think of this?
__________________
Her name is Quicksilver
1978 Chevrolet silverado, shortbox stepside currently being swapped IN is a LM7 5300 vortec, 4l80E, factory 4.11s, slammed, a dream ride and coined QUICKSILVER
gotta pay $$ if you wanna play
chevybuilder18 is offline   Reply With Quote
Old 08-27-2013, 01:14 PM   #2
SCOTI
Registered User
 
SCOTI's Avatar
 
Join Date: Apr 2001
Location: DALLAS,TX
Posts: 22,068
Re: cutting coils, offsets tie rods?

Quote:
Originally Posted by chevybuilder18 View Post
I've drove my truck a couple times after i lowered it and it sucks on handling. i did cut 1 1/4 coils off so i can drop the front 2 inch's and a half. however i noticed this strange tire squeal going down the road, ever time i accelerated, i would swerve just a hair without losing control. even if i managed that, getting the truck to go over hills was hard especially accelerating to 60... its scary. but my theory is the tie rods are pushed out, and take more abuse on this set up. i have not been driving it, ever since i dropped the LM7 in it, lack of a power steering and alternator on the engine. i didnt figure parts like these wouldnt be laying around. especially after 11 years since the vehicles fitted with these engines could have been wrecked... but anyways the thing is i believe i may be able to fix the short cuts we make to save money and time on new lowering springs. the new tolerances on each cut individual coil has changed. hence the load capacity has dropped. if you have cut your coils and not satisfied with handling, this is why. another factor, is the heat you put on them to cut them, of coarse i made sure mine were cool through the whole thing so it wouldnt take strengths away. i have a remedy that may fix this. since load capacity has changed, and there a lil weaker, the springs are bouncing more, causing the ride height to change in the front but not the back. since this happens, the tie rods are pushed and pulled by the height change. I've noticed this, since our trucks rear leafs and axles aren't independent or as heavy as the front. to balance this, there's coil stiffeners out there on the shelf at autozone, aka coil spacers. these spacers are my tactic to try and stiffen the ride, not only that, but better than factory shocks are going to be needed so will an entirely new way of balancing the tie rods.. any one ever think of this?
Cutting coils increases the springs rate over a given amount of travel (if it took 350# of force to compress the spring 1", now it might take 400# to compress it that same inch).

That being said, cutting the coils decreases the amount of available travel but doesn't increase the spring rate enough to balance the difference. This is why you shouldn't cut more than 1 coil. If it takes more than that to set your ride height, you need coils w/more spring rate.

Did you align the front end after cutting the coils? The toe must be reset since the geometry of things has been altered. Caster/camber also has an impact depending on the alignment specs used. What was the alignment set @?

Using the 'coil spacers' is a bandaid @ best & not a good one. Better shocks w/the correct range of travel are a great idea.

Anything worth doing is worth doing right....
__________________
67SWB-B.B.RetroRod
64SWB-Recycle
89CCDually-Driver/Tow Truck
99CCSWB Driver
All Fleetsides
@rattlecankustoms in IG

Building a small, high rpm engine with the perfect bore, stroke and rod ratio is very impressive.
It's like a highly skilled Morrocan sword fighter with a Damascus Steel Scimitar.....

Cubic inches is like Indiana Jones with a cheap pistol.
SCOTI is offline   Reply With Quote
Old 08-27-2013, 04:27 PM   #3
INSIDIOUS '86
Registered User
 
INSIDIOUS '86's Avatar
 
Join Date: Jul 2009
Location: washington
Posts: 4,178
Re: cutting coils, offsets tie rods?

When our trucks are at stock height the tie rods angle down to the spindles. When you cut the springs they angle up much further making your toe angle get really extreme since the tie rods push out. Try running with your toes pointe to the side kinda hard right? So that squealing is from your tires tring to turn right on the right side and left on the left side. They are fighting each other as your driving which vastly increases your rolling resistance this is why it isn't accelerating for beans.

When I got my truck someone had cut the springs to get a 5 inch drop with no spindles. Which resulted in a horrible ride on the bumps stops and horrible toe out. So they aligned it and brought the alignment back in spec the dealer put in three inch lowering springs and raised the front back up but that brought my toe angle way way in a a result and it never got re aligned. Before I knew much about suspension my truck just ate the front tires up. So take a like at the inside an outside of your tires. They should be even with no feathered edges or rubber eraser dust substance.

My before and after 45* is pretty bad.




My specs are pretty harsh for normal driving. 13* toe out with low profile tires would be great and -.5 camber is a good place to start get as much caster as you can. 7.5* was about the most the can get with mine with the specs I provided but I also have an inch forward on my lca's
Posted via Mobile Device
__________________
377 sbc thumpr cam autogear m23 muncie 3:73 Detroit trutrac
3''spintech prostreet mufflers xpipe 1 3/4 headers
build thread !http://67-72chevytrucks.com/vboard/s...d.php?t=577217
Iroc gauge threadhttp://67-72chevytrucks.com/vboard/s...d.php?t=554511
INSIDIOUS '86 is offline   Reply With Quote
Old 08-29-2013, 07:18 PM   #4
chevybuilder18
Registered User
 
chevybuilder18's Avatar
 
Join Date: Mar 2012
Location: Lincoln, IL
Posts: 880
Re: cutting coils, offsets tie rods?

Quote:
Originally Posted by SCOTI View Post
Cutting coils increases the springs rate over a given amount of travel (if it took 350# of force to compress the spring 1", now it might take 400# to compress it that same inch).

That being said, cutting the coils decreases the amount of available travel but doesn't increase the spring rate enough to balance the difference. This is why you shouldn't cut more than 1 coil. If it takes more than that to set your ride height, you need coils w/more spring rate.

Did you align the front end after cutting the coils? The toe must be reset since the geometry of things has been altered. Caster/camber also has an impact depending on the alignment specs used. What was the alignment set @?

Using the 'coil spacers' is a bandaid @ best & not a good one. Better shocks w/the correct range of travel are a great idea.

Anything worth doing is worth doing right....
yea i just figured the cheapest route wouldnt be a good idea. and no i dont have my front end balanced. i have 3 inch drop spindles which with non cut coils could have offset the balance by a hair, however since i did take a coil.. Insidious is correct. the balance is the right is pointing to the right and the left tire is pointing to the left. if i happen to reset the toe, which is now on the agenda, would i also need to fix the cambar?
Quote:
Originally Posted by INSIDIOUS '86 View Post
When our trucks are at stock height the tie rods angle down to the spindles. When you cut the springs they angle up much further making your toe angle get really extreme since the tie rods push out. Try running with your toes pointe to the side kinda hard right? So that squealing is from your tires tring to turn right on the right side and left on the left side. They are fighting each other as your driving which vastly increases your rolling resistance this is why it isn't accelerating for beans.

When I got my truck someone had cut the springs to get a 5 inch drop with no spindles. Which resulted in a horrible ride on the bumps stops and horrible toe out. So they aligned it and brought the alignment back in spec the dealer put in three inch lowering springs and raised the front back up but that brought my toe angle way way in a a result and it never got re aligned. Before I knew much about suspension my truck just ate the front tires up. So take a like at the inside an outside of your tires. They should be even with no feathered edges or rubber eraser dust substance.

My before and after 45* is pretty bad.




My specs are pretty harsh for normal driving. 13* toe out with low profile tires would be great and -.5 camber is a good place to start get as much caster as you can. 7.5* was about the most the can get with mine with the specs I provided but I also have an inch forward on my lca's
Posted via Mobile Device
your right about the toe on my truck, and sorta scary on rain. does this mean ill have to fix the cambar adjustments as well?
__________________
Her name is Quicksilver
1978 Chevrolet silverado, shortbox stepside currently being swapped IN is a LM7 5300 vortec, 4l80E, factory 4.11s, slammed, a dream ride and coined QUICKSILVER
gotta pay $$ if you wanna play
chevybuilder18 is offline   Reply With Quote
Old 08-29-2013, 08:46 PM   #5
INSIDIOUS '86
Registered User
 
INSIDIOUS '86's Avatar
 
Join Date: Jul 2009
Location: washington
Posts: 4,178
Re: cutting coils, offsets tie rods?

Quote:
Originally Posted by chevybuilder18 View Post
yea i just figured the cheapest route wouldnt be a good idea. and no i dont have my front end balanced. i have 3 inch drop spindles which with non cut coils could have offset the balance by a hair, however since i did take a coil.. Insidious is correct. the balance is the right is pointing to the right and the left tire is pointing to the left. if i happen to reset the toe, which is now on the agenda, would i also need to fix the cambar?


your right about the toe on my truck, and sorta scary on rain. does this mean ill have to fix the cambar adjustments as well?
Not necasarily toe I the last angle set on an alignment as everything else effects it. I dropped mine and before the alignment it would jerk around on bigger puddles and drains and such. As long as camber and castor match side to side you can get the toe set quick and easy
Posted via Mobile Device
__________________
377 sbc thumpr cam autogear m23 muncie 3:73 Detroit trutrac
3''spintech prostreet mufflers xpipe 1 3/4 headers
build thread !http://67-72chevytrucks.com/vboard/s...d.php?t=577217
Iroc gauge threadhttp://67-72chevytrucks.com/vboard/s...d.php?t=554511
INSIDIOUS '86 is offline   Reply With Quote
Old 09-03-2013, 01:32 PM   #6
chevybuilder18
Registered User
 
chevybuilder18's Avatar
 
Join Date: Mar 2012
Location: Lincoln, IL
Posts: 880
Re: cutting coils, offsets tie rods?

thank you. i did however notice the tires stand straight up and down when turned, this may have some positive effects right?
__________________
Her name is Quicksilver
1978 Chevrolet silverado, shortbox stepside currently being swapped IN is a LM7 5300 vortec, 4l80E, factory 4.11s, slammed, a dream ride and coined QUICKSILVER
gotta pay $$ if you wanna play
chevybuilder18 is offline   Reply With Quote
Old 09-03-2013, 02:22 PM   #7
INSIDIOUS '86
Registered User
 
INSIDIOUS '86's Avatar
 
Join Date: Jul 2009
Location: washington
Posts: 4,178
Re: cutting coils, offsets tie rods?

Quote:
Originally Posted by chevybuilder18 View Post
thank you. i did however notice the tires stand straight up and down when turned, this may have some positive effects right?
Turning the wheels won't show toe angle really as much as castor and camber combined

From a handling stand point no. From tire wear standpoint it's fine as long as your not driving like an f1 racer. Take a chopper for example if you imagine when the bike leans that that is camber, and that the angle of rake on the forks is castor. If that bike had the wheels turned and the forks up and down the wheel would be straight up and down. If it had lots of rake on the front fork that wheel would tilt back a little which is great for stability in a straight line and helps the vehicle lean in on a corner and play the tires more.

Our trucks lean...a lot so having some negative camber negates the tendacy for the tire to roll out and not plant square when taking a corner. I will post a pic of my wheel at full lock and you will see what I mean

Back in the early 70s when these trucks were made they had fat sidewall tires and were built strictly utilitarian. Alignments were mad to give efficiency and tire life and good driving characteristics on the highway. As you can see 3.7 castor and +.7 camber and 1/16th-1/8ths toe in was factory specs but was fine for a stock truck with tires of those days. You would be hard pressed to see any car these days that conservative.

What you have to do is spec your alignment to match your tire and body roll. Ideally you want your camber to be zero in a corner at your most common turning speed. About 7* castor is normal anymore and is a non tire wearing angle and helps road feel in a corner and will be more stable at high speeds. Toe in is fine for driving, this will keep you stable on the highway through trucker ruts and such and won't wear tires down. Toe when set is set in a way that when your driving down the road the tires pull the suspension and gets rid of slack and is theoretically zero at speed, theoretically because toe changes with ride hight which is never at the same point when driving doe to bumps and such. Toe out can make the truck a little squirrelly at speed due to driving force pulling the wheels out and increasing toe angle all the more at speed. But a good benefit is increased turn in on a corner which means that the vehicle is more responsive to turning than it would be with toe in

I hope that helps in kinda understanding what all the alignment angles do and how.
Posted via Mobile Device
__________________
377 sbc thumpr cam autogear m23 muncie 3:73 Detroit trutrac
3''spintech prostreet mufflers xpipe 1 3/4 headers
build thread !http://67-72chevytrucks.com/vboard/s...d.php?t=577217
Iroc gauge threadhttp://67-72chevytrucks.com/vboard/s...d.php?t=554511
INSIDIOUS '86 is offline   Reply With Quote
Old 09-25-2013, 04:39 PM   #8
chevybuilder18
Registered User
 
chevybuilder18's Avatar
 
Join Date: Mar 2012
Location: Lincoln, IL
Posts: 880
Re: cutting coils, offsets tie rods?

i see what you mean. what scares me is i looked at my cambar adjustments and noticed something wierd. they are shims with a U fork kinda look, and all of em are on the passenger side!!! somebody adjusted the cambar i believe
__________________
Her name is Quicksilver
1978 Chevrolet silverado, shortbox stepside currently being swapped IN is a LM7 5300 vortec, 4l80E, factory 4.11s, slammed, a dream ride and coined QUICKSILVER
gotta pay $$ if you wanna play
chevybuilder18 is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 09:38 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com