rear suspension? 4 link? caltrac mono leaf? street lynx?

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MOPARCODY

MOPARCODY

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im to the point to where id like to upgrade the rear suspension. right now the car runs mid 11s and works very well. Im building a motor that is going to be turbocharged and will make over a grand. what do you guys prefer for higher hp cars. this car gets driven on the street a lot. but i also drag race the car quite a bit.

should i just 4 link it?
should i buy the rms street lynx kit?
will caltracs/mono leafs work for what i want to do?

sorry if this is the wrong subforum
 
What’s the goal for the car? And what tire will you have on the back? Caltracs and monoleafs can work well and there are guys going 5s on em with a drag radial. More street than race, I would go that route. More race than street and a slick I would look at a multi link and coil over set up. Either way spend the money on adjustable shocks.
 
Sounds like drag is your ultimate goal, with that in mind, I say 4 link it.
 
TT5.9mag said:
What’s the goal for the car? And what tire will you have on the back? Caltracs and monoleafs can work well and there are guys going 5s on em with a drag radial. More street than race, I would go that route. More race than street and a slick I would look at a multi link and coil over set up. Either way spend the money on adjustable shocks.
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the car is mini tubbed with/6 springs in the rear with some old school 50/50 competition engineering shocks. it works well at the 400hp mark. the tire is a 325/50/15 et street r radial.
 
MOPARCODY said:
the car is mini tubbed with/6 springs in the rear with some old school 50/50 competition engineering shocks. it works well at the 400hp mark. the tire is a 325/50/15 et street r radial.
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Don’t know what you want to use for a 4 link, but to get one in there is a ton of work. I used and unequal 4 link because the shorter top bar made it easier to get it all in there.

Some pretty fast dudes running leaf springs. I think I’d spend the money on getting rid of the /6 springs in the rear. You need a much higher spring rate back there than that, especially when making the power you are talking about.

So I’d go a Calvert split mono spring. Then I’d order a set of Assassin bars. They have the most adjustability of all that style of traction bar out there, and you need some adjustability.

Then I’d spend the money on some Viking double adjustable shocks for all 4 corners. Again, the ability to adjust as much of your chassis as you can is a big deal.

Then I’d invest in an ignition where you can ramp in the power to help control the application of power.

I’m a huge 4 link fan. Making them fit, and fit correctly is a beeeotch. The learning curve with a 4 link is steep. It’s not a set it and forget it system. Just getting the instant center where it should be is work. And it’s not where most people think it should be. Then the tuning begins.

You should also get as many chassis books as you can find. Read them all. I always plot out a 4 link on the shop floor and then move it paper after that. You need to know what every hole combination gets you for IC. You can’t guess. And every IC will take different shock settings.
 
I run some local street car stuff with my n/a Dart and have done well in the past and can still hold my own against n/a cars. The boosted cars are hard to handle with all the electronics controlling the launch.

That being said I've considered building a 65 Dart I have to run in the class, figure I can lose 500 pounds over what I have now. If I do it will have a four link, no questions about it. Considering the Mustangs that seem to dominate the class for all intents and purposes come from the factory with a four link.

My fear is that if I start beating some of these guys they'll cry and get the rules changed to eliminate back half cars from the class. Then I'd have a bracket car with tags on it.

I hate to admit it but I've considered using my motor in a late 90's, early 2000's mustang just to get the rear suspension. In the long run it makes more sense dollar wise.
 
The street lynx kit is not what you want.

Its lower bar is in the way for mini tubs, it dose not adjust easy and i dont think it would hold up under the power you want.
 
justinp61 said:
I run some local street car stuff with my n/a Dart and have done well in the past and can still hold my own against n/a cars. The boosted cars are hard to handle with all the electronics controlling the launch.

That being said I've considered building a 65 Dart I have to run in the class, figure I can lose 500 pounds over what I have now. If I do it will have a four link, no questions about it. Considering the Mustangs that seem to dominate the class for all intents and purposes come from the factory with a four link.

My fear is that if I start beating some of these guys they'll cry and get the rules changed to eliminate back half cars from the class. Then I'd have a bracket car with tags on it.

I hate to admit it but I've considered using my motor in a late 90's, early 2000's mustang just to get the rear suspension. In the long run it makes more sense dollar wise.
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There is very little room in the early A’s. I loved my but man, getting a 14x32 tire in there, and the 4 link and then fitting a clutch pedal and building headers...lotsa work.

Still my favorite race car though, even though the four letter blasts from smashing my hands, trying to fit it all in there...that was still my favorite car.
 
440outlawdart said:
ladder bar,hooks the hardest,4 link pain in the ***
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440outlawdart said:
ladder bar,hooks the hardest,4 link pain in the ***
Click to expand...


The ladder bar is way too short, not very adjustable and a good set of Asassin bars will do every thing a ladder bar will do.

A 4 link is relatively simple. It’s not a bolt in and go, but it will do anything you ask of it.
 
Ok, didn’t see the street lynx thing and I’d pass on that all day long. As Cope said the bottom bar is in the way of the tub and it’s not adjustable.


Holy CRAP that’s a ton of money. For 2 grand you can do what I said above and have money for lunch left over.

That suspension is for street rod stuff.
 
Street lynx was designed more for handling. It improved my 60' time but I was nowhere near your power level. I'd put something in it designed for the track if it were mine.
 
so caltracs mono leaf with some good adjustable shocks sounds like what you guys are leaning towards. i really dont want to back half the car.
 
MOPARCODY said:
so caltracs mono leaf with some good adjustable shocks sounds like what you guys are leaning towards. i really dont want to back half the car.
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If you are wanting a turbo, I’d seriously look into the Asassin bars. Again, they are much more adjustable, and anything you can do to get the suspension to do more work, the less power you have to take out at the hit to get it hooked.
 
1000 hp? You need all the adjustability you can get. IMHO i would go 4 link and custom valved double adjustables for your final combination. BUT- First i would wear out the phone calling every good chassis builder i could think of to get seasoned, professional advise on this deal. Same with the shocks. I am on my fourth upgrade for rear shocks going from 10s to mid 8s. Get a lot of professional input to make sure you end up with the best combo your$$ will buy.
Once you head down a certain road on this, a lot of $$$ will be committed and it will be tough to correct a less than optimum choice in parts or chassis design.
 
Consider the fact that you are making a quantum leap in power, and have experiance so far that is of little value for your new motor. What you need most is a mentor with experience and proven success in building and tuning a car just like yours AT LEAST as fast as you expect to go.
 
I’ve owned a couple 850+ Hp turbo cars. Nothing this old. So I could definitely Use some guidance
 
MOPARCODY said:
I’ve owned a couple 850+ Hp turbo cars. Nothing this old. So I could definitely Use some guidance
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I agree with Greg. I’m not sure it’s worth any upgrades right now if you are going to make that kind of power. You’d be spending money twice.

For what you want you need the best shock you can get, and it will probably take a couple of tries to get the valving right, and you’ll need a 4 link.

If you don’t have a chassis book, my two favorites are the very hard to find Chris Alston chassis book, which is pretty basic but it has some great info in it.

The other book I like is Dave Morgan’s Doorslammers book. You will learn how important shocks really are, and how to correctly lay out a 4 link. He did make one mistake though, which in late 2002 or early 2003 when he was the editor of the IHRA weekly magazine he corrected.

In his book, he claims that when you install the 4 link, you want the bottom bar parallel to the ground. This is not only wrong, it’s dead wrong, and he admitted this.

Dave’s theory was if the bottom bar was parallel to the ground, you could just raise and lower the top bar and move the Instant Center forward and backwards and not raise or lower the IC at the same time.

The problem with this install is that a parallel bottom bar almost always (99.99999% of the time its wrong) the IC will be too high, no matter where the IC is set relative to its forward postition.

I install/set the bottom bar so that if you draw a line through the bar, that line will intersect with the lower ball joint on the front suspension.

In that position, the bottom bar gets more leverage over the suspension, and you can use the upper bar to set the forward position of the IC.

As an example, in 1986 I converted my car from the worthless ladder bars to an Art Morrison 4 link. The Art Morrison default IC position is (I should say was as I don’t think they even do race car parts anymore, but they may, and I haven’t discussed this with them until I figured out how wrong it was in 1990) half the wheel base forward and cam high up! Holy crap...that will beat the hell out of the tire on even an honest 450 horse engine. And I fought that for several years. I couldn’t get a shock to control the suspension. I forgot, Art Morrison was also big on getting the bottom bar parallel so it wasn’t only Dave Morgan who taught this.

So...on my shop floor, in full size, I laid out all my 4 link positions. I was stunned at what I saw. I learned I needed to get the IC way further forward. With the bottom bar parallel to the ground like that, to get the IC forward to just under the front suspension (that was my best guess at that time...I was running a clutch so getting help on chassis was near impossible) which on my car was 106 inches out. Couldn’t do it. There wasn’t a hole position to get there, and keep the bottom bar parallel.

As I looked at the lines on the ground I realized the IC need to be lower, much lower than cam high. So...to make a long story less long, I moved the back of bottom bar up a hole on the axel, and the lowered the bottom bar one hole on the chassis.

Now, the IC can be any where I want it, as long as it’s not cam high. I can’t think of a situation where a cam high IC would even be close.

I ended up on my best chassis/clutch/shock settings the IC was about 112 inches out and about 3 inches off the ground, and the bottom bar was never parallel to the ground. The shocks (some Koni’s that were ok...nothing like what even a Viking is today) could now handle the speed of the axle movement, where before you couldn’t get the shock stiff enough in rebound or bump.

Ok, that’s my rant on 4 links and 4 link set up. Once you do a full scale layout of all the IC possibilities you can have with a 4 link, you’ll see why the parallel to the ground bottom bar is a horrible starting point.

That is some of what you’ll learn in the Morgan and Alston books.
 
yellow rose said:
I agree with Greg. I’m not sure it’s worth any upgrades right now if you are going to make that kind of power. You’d be spending money twice.

For what you want you need the best shock you can get, and it will probably take a couple of tries to get the valving right, and you’ll need a 4 link.

If you don’t have a chassis book, my two favorites are the very hard to find Chris Alston chassis book, which is pretty basic but it has some great info in it.

The other book I like is Dave Morgan’s Doorslammers book. You will learn how important shocks really are, and how to correctly lay out a 4 link. He did make one mistake though, which in late 2002 or early 2003 when he was the editor of the IHRA weekly magazine he corrected.

In his book, he claims that when you install the 4 link, you want the bottom bar parallel to the ground. This is not only wrong, it’s dead wrong, and he admitted this.

Dave’s theory was if the bottom bar was parallel to the ground, you could just raise and lower the top bar and move the Instant Center forward and backwards and not raise or lower the IC at the same time.

The problem with this install is that a parallel bottom bar almost always (99.99999% of the time its wrong) the IC will be too high, no matter where the IC is set relative to its forward postition.

I install/set the bottom bar so that if you draw a line through the bar, that line will intersect with the lower ball joint on the front suspension.

In that position, the bottom bar gets more leverage over the suspension, and you can use the upper bar to set the forward position of the IC.

As an example, in 1986 I converted my car from the worthless ladder bars to an Art Morrison 4 link. The Art Morrison default IC position is (I should say was as I don’t think they even do race car parts anymore, but they may, and I haven’t discussed this with them until I figured out how wrong it was in 1990) half the wheel base forward and cam high up! Holy crap...that will beat the hell out of the tire on even an honest 450 horse engine. And I fought that for several years. I couldn’t get a shock to control the suspension. I forgot, Art Morrison was also big on getting the bottom bar parallel so it wasn’t only Dave Morgan who taught this.

So...on my shop floor, in full size, I laid out all my 4 link positions. I was stunned at what I saw. I learned I needed to get the IC way further forward. With the bottom bar parallel to the ground like that, to get the IC forward to just under the front suspension (that was my best guess at that time...I was running a clutch so getting help on chassis was near impossible) which on my car was 106 inches out. Couldn’t do it. There wasn’t a hole position to get there, and keep the bottom bar parallel.

As I looked at the lines on the ground I realized the IC need to be lower, much lower than cam high. So...to make a long story less long, I moved the back of bottom bar up a hole on the axel, and the lowered the bottom bar one hole on the chassis.

Now, the IC can be any where I want it, as long as it’s not cam high. I can’t think of a situation where a cam high IC would even be close.

I ended up on my best chassis/clutch/shock settings the IC was about 112 inches out and about 3 inches off the ground, and the bottom bar was never parallel to the ground. The shocks (some Koni’s that were ok...nothing like what even a Viking is today) could now handle the speed of the axle movement, where before you couldn’t get the shock stiff enough in rebound or bump.

Ok, that’s my rant on 4 links and 4 link set up. Once you do a full scale layout of all the IC possibilities you can have with a 4 link, you’ll see why the parallel to the ground bottom bar is a horrible starting point.

That is some of what you’ll learn in the Morgan and Alston books.
Click to expand...

ill have to pick up an alstan book. Theyre local to me so i might just stop by and see if they have one laying around. the whole idea of me wanting a leaf spring is to not have to back half the car. can a 4 link be done and keep most of the factory metal in the rear?
 
MOPARCODY said:
heads up street/drag racing..
Click to expand...

Cal tracs or assasin bars, monoleafs and good shocks and a good drag radial tire. Get the weight down. And do something for engine management with traction control. If you make 1000hp you’ll need it.
 
TT5.9mag said:
Cal tracs or assasin bars, monoleafs and good shocks and a good drag radial tire. Get the weight down. And do something for engine management with traction control. If you make 1000hp you’ll need it.
Click to expand...

car is 2840 without me in it but thats with the old iron 360 motor, the new bullet is a 370ci all aluminum motor and an aluminum reid case power glide. car has a fiberglass front end. will eventually have fiberglass deck lid and door skins as well.
 
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