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robnolimit 04-23-2012 12:02 PM

Re: Make it handle
 
As to welding on a swaybar, I am not for it, if your talking about it welding anywhere in the center of the bar, such as narrowing the bar. But, if we're talking about cutting off the factory end, and welding on new tabs for the link, then it's OK in my book.

INSIDIOUS '86 04-23-2012 04:30 PM

Re: Make it handle
 
Quote:

Originally Posted by robnolimit (Post 5331108)
As to welding on a swaybar, I am not for it, if your talking about it welding anywhere in the center of the bar, such as narrowing the bar. But, if we're talking about cutting off the factory end, and welding on new tabs for the link, then it's OK in my book.

A sway bar is basicly a torsion bar or uncoiled spring. By welding on a part that twists like the middle or on the bends can compromise the bar and change how it acts or cause it to break.by welding tabs on the ends there shouldn't be an issue with compromising strength as long as the welds are strong, since tends go up and down and there is hardly any twisting action.

Any issue with what's stated above?
Posted via Mobile Device

robnolimit 04-24-2012 11:43 AM

Re: Make it handle
 
I have to agree with that. - better stated than me, thanks.

INSIDIOUS '86 04-24-2012 12:13 PM

Re: Make it handle
 
Say rob how about showing us ways to diagnose handling issues and how to tune them out? Like oversteer and understeer loose entry or exits etc...
Posted via Mobile Device

Matt R 04-26-2012 07:56 PM

Re: Make it handle
 
Quote:

Originally Posted by robnolimit (Post 5331108)
As to welding on a swaybar, I am not for it, if your talking about it welding anywhere in the center of the bar, such as narrowing the bar. But, if we're talking about cutting off the factory end, and welding on new tabs for the link, then it's OK in my book.

Cool that will be a great tuning tool to put in the tool bag!

duallyjams 04-26-2012 10:52 PM

Re: Make it handle
 
I have a question regarding the track bar , I don't see anyone using a wish bone instead.

robnolimit 04-28-2012 06:08 PM

Re: Make it handle
 
While wishbones are used in many applications, they can be somewhat complicated. There are two types, 'coupled', and 'uncoupled'. A 'coupled' wishbone also acts as the upper or lower bar set, sort of like a triangulated 4-bar. An 'uncoupled' wishbone must be fabricated with a 'slide' section to get shorter/longer so that it doesn't bind with the 3 or 4 link bars during travel. Coupled wishbones do move straight up and down, with no side to side movement, as long as both tires are moving up/down the same. If the axle 'tips', say in a corner, then the coupled wishbone tends to do goofy things trying to steer the rear end, and or bind up. These issues, combined with the complicated nature of fab, install, and packaging in the vehicle, are why you don't see to many around.

robnolimit 04-28-2012 06:37 PM

Re: Make it handle
 
Quote:

Originally Posted by INSIDIOUS '86 (Post 5333224)
Say rob how about showing us ways to diagnose handling issues and how to tune them out? Like oversteer and understeer loose entry or exits etc...
Posted via Mobile Device

OK, good one. I've been working on a chart to hand out and put in the goody bags at shows for this, so you guys can tell me if this stuff makes sense to you.

First of all, he said WHAT? Oversteer, understeer, loose..... ???? Great place to start. Oversteer, or a Loose condition is when the truck rotates more than the corner your in. This can also be called being Loose. you turn the wheel, the truck turns in with the front tires, and the back tends to come around, or rotate, causing the truck to be pointing too far into the turn, or a spin. (see video of the Hell Boy @ Del Mar) Understeer, or a Push, is when the truck rotates less than the corner your in, trying to go straight. Such as, you turn the wheels, the truck goes straight, or Pushes forward.

Trucks have weight balance issues that cause them to 'push' into a corner, and be 'loose' on the way out.

We need to talk about this corner also. If you do it right, so I am told, you brake before the corner, slowing down, then turn the wheels, then, smoothly apply power coming out of the corner and let the truck 'unscrew' itself onto the straight. Thats what they tell me. So, the truck is decelerating into the corner, weight shifting forward, and accelerating out of the corner, weight shifting back. Thats why you truck acts different at different places in the corner.

Tuning is all about finding the best balance of these for your truck. Somethings you can do easy, and for some you have to build another truck. And, if we built them 100% purpose built to go around corners, they would look like corvettes, what fun would that be. Can't haul the big party cooler in a vette.

Tires pressure and alignment are cheap.

TIRE PSI
In general, if you have 'push', lower the front tire pressure/raise the rear. If the truck is generally 'loose', raise the front psi./drop the rear. Try this in 1 or 2 psi changes. Also, get a tire marker (yellow lumber crayon will do) and color a 1/2" wide stripe across the tread of each tire, drive it around the block and see how it wears. Center clean = psi to high, outsides clean = psi to low.


Good so far?

Andy4639 04-28-2012 08:26 PM

Re: Make it handle
 
I like that. I understood all of it. My dad told me the same thing when I was just starting to drive to brake before a curve and never in it unless all else fails. Also to gas it to pull it out of the turn and get it straight.
Good info man. I like the crayon to!
;):chevy:

GEARBOXGARAGE 04-29-2012 04:39 PM

Re: Make it handle
 
Going back a ways in this thread, Rob (robnolimit) referenced a quote from Days of Thunder. "Tires win races." A tire is only going to hold so much traction, even in perfect world conditions. Cole Trickle thought he was fast because he didn't lift his foot and was over-riding the tire's ability to use traction for steering through the turns. (Something my boy will be getting a lesson in this year at the local kart track) The same goes for braking. If you're braking through the corner, the tire's ability to change the direction of momentum is being taken away by the traction used in the braking action. Pick a favorite corner and experiment with different points to start braking from. If you have a buddy that can time you with a stop watch, that will be even better. You're probably going to find that, even though you feel slow going through the turn, it will actually be faster by the stop watch. Once you find you sweet spot, focus on repitition. If you're hitting a favorite local track, you can do this for every corner, then all you have to worry about is connecting the dots between turns.

Andy4639 04-29-2012 07:11 PM

Re: Make it handle
 
As the old say goes...sometimes you have to slow down to go fast!

One thing that I keep in mind is my ablitity to feel the truck are vehicle that I'm driving.
My wife wouldn't dare take a turn at over 60 MPH no matter what, she has no feel for the vehicle. I do it on a regular bases because I can feel the vehicle.
As back to the movie Dats of Thunder
Trickle couldn't tell them what the car was doing while on the track.
;)

66shortwide 04-30-2012 10:24 AM

Re: Make it handle
 
As it was explained to me, when a vehicle understeers(pushes, tight) the rear has more grip than the front, and when it oversteers(loose) the front has more grip than the rear. So the balance is what we are looking for - equal grip front and rear, but just as mentioned earlier weight transfer affects it also.

robnolimit 04-30-2012 11:32 AM

Re: Make it handle
 
Yep, thats the basics. Now here are some rules to follow. 1. Work on the problem. Sounds simple, but we can easily be led a stray. If the front has a push, work on the front, don't tighten up the rear to make it loose as a solution. 2. One thing at a time. This is another tough one for us. Don't start throwing parts at your truck, springs, shocks, swaybars.... Just do one at a time, and log the results. 3. Stopwatches are smarter than you. This also means Test-Test-Test. You may make a change that feels faster, but actually slows the truck down. Jerky and twitchy feel fast, but aren't. Find a place that you can consistantly run through, set start and stop points, and test. There are some cheap I-phone apps now that will use GPS and time a section for you. - BE SAFE. 4. It's all about happy tires. once the tire is unhappy, your done. A givin tire can only provide so much traction, thats it. Your job is to use as much of that as you can, as efficiently as you can, for braking, turning and acceleration. 5. Learn to drive. We all think we can, but really, what do you know? A good driver can get more out of your car/truck than you ever dreamed, trust me on this one. High performance driving schools are expensive, but worth it if you can do it. Try going go-carting on a regular basis, we go once a month, it helps. So thats the rules we try to follow. Notice I said try. We're all human. Get a little notebook and start keeping track of things, it's the nerd way, but it works. Be Smooth, Be Steady, and Be Fast.

INSIDIOUS '86 05-02-2012 12:32 AM

Re: Make it handle
 
http://www.classicparts.com/1971-87-...nfo/74%2D157B/

What do you guys think of these? Looks like the spring pocket is located aft to keep the spring straight. Don't think I have seen anybody else offer something like these for the squares
Posted via Mobile Device

robnolimit 05-02-2012 01:07 AM

Re: Make it handle
 
Well, actually I think thats a really good sign. I haven't seen these before, and I don't know how long they've been around, BUT, others are starting to get it. You can't just copy a stock arm from tube and say it's better. The manufacturer is not stated. If the quality is good, this is propably a nice upgrade. Has anybody here run these?? The other thing I learned from this is, I need to raise my price on a-arms. lol

INSIDIOUS '86 05-02-2012 02:02 AM

Re: Make it handle
 
Quote:

Originally Posted by robnolimit (Post 5348451)
Well, actually I think thats a really good sign. I haven't seen these before, and I don't know how long they've been around, BUT, others are starting to get it. You can't just copy a stock arm from tube and say it's better. The manufacturer is not stated. If the quality is good, this is propably a nice upgrade. Has anybody here run these?? The other thing I learned from this is, I need to raise my price on a-arms. lol

Haha if you can make me a cheaper set I'm in!
Posted via Mobile Device

gringoloco 05-02-2012 10:36 AM

Re: Make it handle
 
Quote:

Originally Posted by INSIDIOUS '86 (Post 5348498)
Haha if you can make me a cheaper set I'm in!
Posted via Mobile Device

Was thinking that, too. What's a set of NoLimit arms run?

Those are CPP arms, btw...

GEARBOXGARAGE 05-02-2012 02:38 PM

Re: Make it handle
 
Quote:

Originally Posted by INSIDIOUS '86 (Post 5348415)
http://www.classicparts.com/1971-87-...nfo/74%2D157B/

What do you guys think of these? Looks like the spring pocket is located aft to keep the spring straight. Don't think I have seen anybody else offer something like these for the squares
Posted via Mobile Device

If I remember right, Classic Parts is a distributor of Classic Performance Products (CPP). Those look exactly like what I just ordered for a customer's '66 C10. He just finished up the install and I went to check them out. Many of the magazines have run articles on them and the quality definately seems to be there. Seems like they give about a 5-6º caster gain. Hope this helps.

robnolimit 05-03-2012 11:41 AM

Re: Make it handle
 
Have you drivin on these arms? Mark Turners green C-10 is using these. I beleive, and it was very impressive last year in texas at the GoodGuys autocross.

robnolimit 05-03-2012 11:53 AM

Re: Make it handle
 
OK Tuners, CASTER
Caster is the 'rake' of the front spindle. like a bike fork. The lower ball joint should be a bit in ahead of the upper ball joint and the angle that the spindle leans back is the caster. Caster is used for stability and handling. As a basic rule, More caster will increase stability, but, at some point the steering will get tighter, and the edges of the tires will start to wear. I would say that 5 to 7 deg is a reasonable street setting.

robnolimit 05-03-2012 12:26 PM

Re: Make it handle
 
Caster vs. cross weight (wedge)
Now, those of you with a lot of cirlce track experience, be gentle with me. Cross weight, or wedge, on a circle car, would be the percentage of weight carried on the right front/left rear, and is used to tune the cars handling. more wedge will tighten the car (more rear grip), and less wedge will loosen the car (more front grip) Keep that in mind.
On street cars/trucks, we usually want a base set-up with even cross weight (wedge), at appx 50%, so that it will turn the same left or right. Now then, Caster has an effect on wedge. Lets say you have 5* caster, and you turn left (for the circle guys), the caster angle will have an effect on the tire loading, adding down force on the 'inside' or left front tire. This effectively 'lowers' the wedge % on the right front/left rear. this would tighten the car, and improve corner entry, but, may make the car loose through the middle of the corner. Remember that we started with 50% wedge, or nuetral, so the effects of this will be the same for both a right and left turn. Wheel and tire width / offset / and scrub radius will also come into play here. Also, too much caster will make the truck dart into a turn. So, again, this is a test & tune.
You don't always need an alignment rack. If your truck is aligned, you have a baseline. To increase the caster, add one shim to the front stud, and remove one from the rear. (same thickness each) The camber/toe wil not change much. Then go drive it. If you like it, go for more. Again, bust out the lumber crayon and check the tire wear. If you run out of alignment room, then it's time for different A-arms. Keep count of the spacers you add/pull, and you can go back to your original alignment any time.

robnolimit 05-03-2012 03:22 PM

Re: Make it handle
 
http://youtu.be/alZdqiJcrZw

Learning to post video. haha. this is from the Hell Boy last tues night. We need more light.

INSIDIOUS '86 05-04-2012 02:30 PM

Re: Make it handle
 
Quote:

Originally Posted by robnolimit (Post 5350817)
Caster vs. cross weight (wedge)
Now, those of you with a lot of cirlce track experience, be gentle with me. Cross weight, or wedge, on a circle car, would be the percentage of weight carried on the right front/left rear, and is used to tune the cars handling. more wedge will tighten the car (more rear grip), and less wedge will loosen the car (more front grip) Keep that in mind.
On street cars/trucks, we usually want a base set-up with even cross weight (wedge), at appx 50%, so that it will turn the same left or right. Now then, Caster has an effect on wedge. Lets say you have 5* caster, and you turn left (for the circle guys), the caster angle will have an effect on the tire loading, adding down force on the 'inside' or left front tire. This effectively 'lowers' the wedge % on the right front/left rear. this would tighten the car, and improve corner entry, but, may make the car loose through the middle of the corner. Remember that we started with 50% wedge, or nuetral, so the effects of this will be the same for both a right and left turn. Wheel and tire width / offset / and scrub radius will also come into play here. Also, too much caster will make the truck dart into a turn. So, again, this is a test & tune.
You don't always need an alignment rack. If your truck is aligned, you have a baseline. To increase the caster, add one shim to the front stud, and remove one from the rear. (same thickness each) The camber/toe wil not change much. Then go drive it. If you like it, go for more. Again, bust out the lumber crayon and check the tire wear. If you run out of alignment room, then it's time for different A-arms. Keep count of the spacers you add/pull, and you can go back to your original alignment any time.


Now isn't caster a non tire wearing angle? Or does the caster effect the camber as the wheel is turned causing more wear?
Posted via Mobile Device

robnolimit 05-04-2012 03:55 PM

Re: Make it handle
 
Caster is a 'non wearing' angle, as long the wheels are straight forward. When you turn the wheels, the caster angle adds or subtracts from the static camber. So, too much caster can wear the edges of the tires. This is where a heat gun comes in handy, and it's cheaper than new skins up front.

robnolimit 05-08-2012 11:41 AM

Re: Make it handle
 
How about TOE. Toe in, or toe out. If anyone has ever set the toe at dead 'O', you know thats not the answer. The steering is less than responsive, and the truck/car tends to wander. With 'O' toe, there is nothing to keep the steering joints 'taught', and the truck can wander around a bit. There are alot of differnt ideas about how toe should be set, and they change with tire size, suspension type, driving style....... Remember that the toe setting has to work in harmony with the caster/camber and others too.
A little toe in will keep it going straight, no wandering, but, the steering may be a bit slow to respond. This is a good factory style set up, for the average driver thats not paying attention too often. A little toe out will keep things going straight, but the car/truck will 'turn in' much quicker. Adding more toe out can help to increase the ability to make tight low-to-medium speed corners (autocross), but will make the vehicle react VERY quickly to any steering input at speeds.
Toe is something that I think is overlooked a lot at short track events, or even in our daily driving. A toe change is easy to make, and, don't panic, you don't need any guages or measuring equipment. IF you start with a known toe setting, lets say you've had it aligned, and you know where it is, you can make changes, try it out, and change back to the known set up any time. Start with a paint pen, or center punch, and make a mark on the front edge of the adjuster sleave for the tie rod end. Do this on each tie rod. From your 'known' setting, loosen the lock bolts and rotate the sleave 1 full turn, so that your mark isback to its same location. do this on each side. It is true that you may not know the measured toe setting, but you do know that it is +1 from your base setting. Any time you want to go back to the base setting, just loosen the lock bolts and go one full turn back. I ALWAYS do the same adjustment to each side, 1/2 turn, or full turn, that helps me keep everything balanced. Try it out, and watch the tire wear. You will never get an alignment shop to set your truck up just for you, they will always go to factory spec. (sorry Doc, there may be some exceptions) If you want it to fit you, you'll have to do it yourself.


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