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-   -   Make it handle (https://67-72chevytrucks.com/vboard/showthread.php?t=419251)

jlsanborn 07-13-2012 07:10 PM

Re: Make it handle
 
Rob,
I've sent you PM regarding my No Limit parts. Look forward to seeing your column! When do you suppose the first issue date would be? Have a specific topic picked out?

robnolimit 07-20-2012 12:48 PM

Re: Make it handle
 
SHOCKSI'm seeing a lot of talk here lately about shocks, so how about we talk about them here. First we all need to understand what a shock is. A shock is a dampner, or a device used to control the suspesion movement, by regulating how fast the suspension can compress or rebound givin a certian amount of load. The shock works in two directions. Compresion and rebound, or closing and opening. On most cars and trucks, the compresion rate is different than the rebound rate to make the car/truck feel balanced. Some of the forces that come in to play are, the total weight of the vehicle, the corner weight per shock, the motion ratio of the suspesion/shock travel, shock angle, unsprung weight, weight transfer due to braking, acceleration and/or cornering, speed, and size and shape of the road surface, and or bumps.
Here's where we're all screwed - we own trucks. The shock world is focused on cars. Performance, ride quality, testing..., it's all about cars. Except for off road shocks, built for a certain type of truck, still, not for a performance oriented street truck. So, your screwed. - until you learn about shocks AND trucks.
Why is a truck so different? Take a look and remember all tha factors that go into a shock. Your truck is REALLY nose heavy. also, the rear is REALLY light. The truck is too heavy, and the center of gravity us too high. This means it has a lOT more weight transfer under braking, acceleration, cornering, than a car. Truck susension parts are heavy, and we run bigger, heavier wheel and tire combos, so unsprung weight is way up too. all of this is bad. Now remember this, ALL performance shocks are designed for cars.
So, its up to you to think about it, and figure out how to pick shocks that might help. When we started with Romic shocks, They were, and still are, really good about working with us to get what we wanted. Most companies sell "coil-overs", front or rear, whatever, same part. So we kept going back to them - Rear shocks must be softer, again. and front compression must be firmer, again, and again. We would test, they would dyno, build more, we test, ..... Here is what we came up with.
First of all, most springs, on most trucks, are WAY TOO STIFF. They are trucks afterall, and, the aftermarket seams to copy the stock spring, but shorter, and most times, even stiffer. - not helping. This makes the shock problem even harder. Weight is a big issue, so front shocks are way different than rear shocks. For basics, we need a front shock that has a firm compression, and even firmer rebound. On the rear, we need a really soft compression, and a medium/firm rebound.

INSIDIOUS '86 07-20-2012 06:11 PM

Re: Make it handle
 
If i call bilstein can they make a custom shock that will work for these trucks?
Posted via Mobile Device

robnolimit 07-20-2012 07:26 PM

Re: Make it handle
 
Many shock manufacturers can do custom builds, but you may have to tell them what you want. This is exactly why I wanted to start this discussion. Many people have commented how they are happy, or unhappy, with a certain shock. I have found that I need to mix and match to get what I want.
I used to use a lot of shocks from Carrera Shocks. They were bought out by Q-A1. They had some performance spec shocks that you could cutom order based on three things. Length, Mounting, andValving. The valving was based on a 1 to 9 scale, 1 = xx soft, 9 = xx firm. Split valve shocks were, and are available, and when discussing valving, the compression number goes first. I found that most of the trucks we built were very nice to drive with a 6/5 front, 7/6 for big block trucks, and a 3/6, or 3/7 rear shock. Also I learned that gas pressurized mono tube shocks are ok in the front, but are not soft enough for the back. Afco, Speedway, and others offer shocks like this. But WE have to know what to get, and this may require changing some mounts.

fatgump 07-20-2012 08:50 PM

Re: Make it handle
 
Quote:

Originally Posted by robnolimit (Post 5496758)
Many shock manufacturers can do custom builds, but you may have to tell them what you want. This is exactly why I wanted to start this discussion. Many people have commented how they are happy, or unhappy, with a certain shock. I have found that I need to mix and match to get what I want.
I used to use a lot of shocks from Carrera Shocks. They were bought out by Q-A1. They had some performance spec shocks that you could cutom order based on three things. Length, Mounting, andValving. The valving was based on a 1 to 9 scale, 1 = xx soft, 9 = xx firm. Split valve shocks were, and are available, and when discussing valving, the compression number goes first. I found that most of the trucks we built were very nice to drive with a 6/5 front, 7/6 for big block trucks, and a 3/6, or 3/7 rear shock. Also I learned that gas pressurized mono tube shocks are ok in the front, but are not soft enough for the back. Afco, Speedway, and others offer shocks like this. But WE have to know what to get, and this may require changing some mounts.

Is there a shock you would recommend to go with your Nolimit rear shock relocate mounts?

jlsanborn 07-20-2012 09:55 PM

Re: Make it handle
 
So what about us non-racers / daily drivers that wanna stay around a couple hunny for four shocks and buy them at Napa? What would you recommend? Also, how would you calculate stroke length?

jlsanborn 07-20-2012 10:01 PM

Re: Make it handle
 
Quote:

Originally Posted by jlsanborn (Post 5484566)
Rob,
I've sent you PM regarding my No Limit parts. Look forward to seeing your column! When do you suppose the first issue date would be? Have a specific topic picked out?

Rob,
FedX just stopped by. Thanks! Another PM sent.

Mechanic77 07-20-2012 11:42 PM

Re: Make it handle
 
I don't want to complicate the shock discussion too much, but doesn't shock mounting location/angle also affect what valving is required? Like, how much difference for rear shock valving would there be for stock mounting location vs. your relocated mounts that put the shocks considerably closer to the wheels and more vertical (on a lowered truck)?

GMC Canuck 07-20-2012 11:53 PM

Re: Make it handle
 
ok, I'm in the planning stages of a tear down rebuild. I love my truck and it pains me to tear it apart cause I know this is more than a winter project but it's lasted 45 years and if it going to last another 45 some things need to be done.

I like the idea of a complete package. I know my strengths and happily defer to smarter people than me who have put together a system of parts that all works well together not the current mishmash of shinny bits I currently own.

I'm looking at no limits wideride front and fatbar rear or porterbuilts dropmember and tubular trailer arms setup or hotchkis' setup

Rob has mentioned several times about unsprung weight so it seems important (I know it is) and so I like his wideride setup. But for the rear, do I need a huge truck 12 bolt. Nope, the truck is never going to haul much more than a cooler. It's done it's time, paid it's dues and can now settle into a nice midlife crisis. I have a toyota to beat the crap out of. I've looked at irs but a custom setup is beyond my budget and retrofitting something like a mark VIII looks like a huge project with limitations on brake, wheel and ratio options. So is there a solid rear axle with a similar track width but maybe a little lighter? I'm not running any huge numbers for horsepower (375-400)

and thank you Rob and everyone else that has contributed or asked some really good questions.

Grimee 07-21-2012 12:47 AM

Re: Make it handle
 
for my money I would go with Robs Parts first class stuff He talks the talk and most important he walks the walk

jlsanborn 07-22-2012 02:14 PM

Re: Make it handle
 
Quote:

Originally Posted by Mechanic77 (Post 5497133)
I don't want to complicate the shock discussion too much, but doesn't shock mounting location/angle also affect what valving is required? Like, how much difference for rear shock valving would there be for stock mounting location vs. your relocated mounts that put the shocks considerably closer to the wheels and more vertical (on a lowered truck)?

The greater the angle, the greater the disadvantage the shock is at. The shock will have to rotate more at the moutning points as well.

Think of it like this....

If the shock were perfectly vertical, then 1" of spring compression would result in 1" of shock travel and zero rotation at the mounts. Now put that sucker at 45 degrees. The same 1" of spring compression results in much less shock travel and it's had to rotate a few degrees on the mounts. So, your shock now has to "absorb" the same amount of "energy" with reduced displacement.

That's about everything I know about shocks! Actually, I don't know jack about shocks, but the geometry makes sense don't it? :smoke:

robnolimit 07-22-2012 03:30 PM

Re: Make it handle
 
Good one, right on the money. As you change the angle of the shock away from the true path of suspension travel, the dampening rate drops. Here are some calcs from old notes.
Shock angle - Dampening
0* 100%
10* 96%
15* 93%
20* 89%
25* 82%
30* 75%
35* 66%
40* 59%
45* 50%
You can see that the farther you lay a shock over, the more rapidly it looses effective dampening. These factors also hold true for spring rates, such as on a coil over shock. Understanding these relationship can help a chassis builder tune a vehicle suspension. Heres an example. Lets say you want the shock to have 200lb/in/sec (simplified term) dampening rate, but all you have available to use is a shock with a 300lb/in/sec shock. If you were to mount this shock at a 35* angle off of the true suspension travel line, you would reduce its effective dampening to 66%. So, 300lb/in/sec x 66% = 198lb/in/sec dampening rate. This relationship between mounting angle and dampening rate can be a good thing, for those who understand it, or a bad thing for those who don't.

robnolimit 07-27-2012 06:30 PM

Re: Make it handle
 
Got my new copy of StreetTrucks today. looks good. WOW, I've been published! + a btchen C10 on the cover

GEARBOXGARAGE 07-27-2012 07:32 PM

Re: Make it handle
 
Quote:

Originally Posted by robnolimit (Post 5508728)
got my new copy of streettrucks today. Looks good. Wow, i've been published! + a btchen c10 on the cover

nice work!!

Blitz 07-28-2012 11:42 AM

Re: Make it handle
 
Looks like I have lots of reading, rereading, taking notes, comparing notes and editing notes to do. For now, I'm just trying to concentrate on what would make a 93 street truck perform and ride best based on a 4/6 or 5/7 drop in three different scenarios. Budget, Mild and Wild.

gringoloco 07-28-2012 12:15 PM

Re: Make it handle
 
What month? I'm no longer a subscriber, but I'd like to grab a copy
Posted via Mobile Device

robnolimit 07-28-2012 01:03 PM

Re: Make it handle
 
Quote:

Originally Posted by Blitz (Post 5509775)
Looks like I have lots of reading, rereading, taking notes, comparing notes and editing notes to do. For now, I'm just trying to concentrate on what would make a 93 street truck perform and ride best based on a 4/6 or 5/7 drop in three different scenarios. Budget, Mild and Wild.

The first steps of the plan should go like this. 1) Loose wieght, and move weight. Down and back. 2) move weight down - lower the truck, but don't get out of the sweet-spot of the suspension (drop spindles first) 3) Tires are everything. the wider the better. 40 series or shorter. 4) shocks, swaybars and alignment, this stuff is important.

robnolimit 07-28-2012 01:14 PM

Re: Make it handle
 
Quote:

Originally Posted by gringoloco (Post 5509818)
What month? I'm no longer a subscriber, but I'd like to grab a copy
Posted via Mobile Device

it's the September 2012 issue

INSIDIOUS '86 07-30-2012 08:33 PM

Re: Make it handle
 
I see your f*rd is on fleabay! What for?
Posted via Mobile Device

hotrod1 07-30-2012 09:28 PM

Re: Make it handle
 
Rob:

Congrats on the article. You deserve it!

robnolimit 07-31-2012 12:28 AM

Re: Make it handle
 
Thanks HotRod1
Sid The garage is full, the shop is full, the trailer is full, and if you know about so-cal real estate, more space isn't an option. HellBoy took the last spot and Tina's mustang is coming along quickly. Someone else needs to know what it's like to drive a bad ass F-100. ?? Could be you

robnolimit 08-01-2012 12:14 PM

Re: Make it handle
 
How to get the BEST DEAL EVER I made a comment on another thread here about buying an IFS. It may have sounded like I was steering the OP towards our product. Yes, thats how I make a living, but that wasn't my goal. Everyday I talk to people about their projects, and more than half of the stories are not so good. Poor quality parts, bad shop experience, over budget, too long....... Many of them are removing parts they bought and installed, only to be unhappy with the outcome. This is the heart of the problem. So how do you get the best deal without getiing screwed? Do your Homework. Ask the right questions, and if you don't know which ones to ask, ask about that too. Forming a relationship with a builder or retailer will help. Not a virtual relationship, but a personal one. Call them on the phone, or stop buy. But, don't waste their time, be ready, have a notepad and pen, and listen to what they say. Think about why they may say these things. Never buy on impulse. You can get Price, Quality, or Service. - But you can't have all three. Most of us are building what amounts to a 4000 lb. bomb. If you plan on driving your truck on a public road, with your wife, girlfriend, and/or kids, set out to make it safe enough for the HP you put in it. Our goal is to grow the classic truck hobby in general. More people building and driving more old trucks. To do that, we have to finish them, drive them, and live through the experience.
p.s. - never put your wife and girlfriend in the truck at the same time.

jmsaunders 08-01-2012 12:42 PM

Re: Make it handle
 
Quote:

Originally Posted by robnolimit (Post 5517295)
How to get the BEST DEAL EVER p.s. - never put your wife and girlfriend in the truck at the same time.

Not even if they are the same person????? I tend to think of my wife as my girlfriend lol.

CRGRS 66 08-01-2012 12:45 PM

Re: Make it handle
 
Quote:

Originally Posted by robnolimit (Post 5517295)
How to get the BEST DEAL EVERp.s. - never put your wife and girlfriend in the truck at the same time.

:blah::but::blah:

no kidding, one in each ear... sage advice Rob

PBFAB.COM 08-01-2012 12:55 PM

Re: Make it handle
 
Quote:

Originally Posted by robnolimit (Post 5517295)
How to get the BEST DEAL EVER I made a comment on another thread here about buying an IFS. It may have sounded like I was steering the OP towards our product. Yes, thats how I make a living, but that wasn't my goal. Everyday I talk to people about their projects, and more than half of the stories are not so good. Poor quality parts, bad shop experience, over budget, too long....... Many of them are removing parts they bought and installed, only to be unhappy with the outcome. This is the heart of the problem. So how do you get the best deal without getiing screwed? Do your Homework. Ask the right questions, and if you don't know which ones to ask, ask about that too. Forming a relationship with a builder or retailer will help. Not a virtual relationship, but a personal one. Call them on the phone, or stop buy. But, don't waste their time, be ready, have a notepad and pen, and listen to what they say. Think about why they may say these things. Never buy on impulse. You can get Price, Quality, or Service. - But you can't have all three. Most of us are building what amounts to a 4000 lb. bomb. If you plan on driving your truck on a public road, with your wife, girlfriend, and/or kids, set out to make it safe enough for the HP you put in it. Our goal is to grow the classic truck hobby in general. More people building and driving more old trucks. To do that, we have to finish them, drive them, and live through the experience.
p.s. - never put your wife and girlfriend in the truck at the same time.

Rob-

This is one of the main reasons I respect you and your company. It is always refreshing to see another vendor who shares similar principles and values. Sound advice all the way around!

If I were to emphasize anything you mentioned, it would be the planning process. Take your time in the "discovery" portion of the process. Ask LOTS of questions. Know what you are building BEFORE you build it. This will help ensure that all parts will work together to achieve the desired end result. A clear and solid plan will do nothing more than save time and money in the long run!

Nate


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