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View Full Version : triangulated 4 bar or a three link



Young Gun
03-25-2008, 04:05 PM
Which do I wanna go with on the AME frame to get the best handling? if yall could tell me the pros and cons of each i would be eternally grateful! Thanks guys!

Young Gun - Colin

Young Gun
03-25-2008, 07:11 PM
and yes I did read the thread right above it, but I didnt really get a clear cut which is better and why, so if anybody can just sparknotes it for me, feel free to post...or just shoot me a pm and ill be grateful!

Norm Peterson
03-26-2008, 03:51 AM
Cliff's Notes version: The 3-link does a better job of separating the cornering duties of the suspension linkages from the acceleration/braking chores. In any sane geometric arrangement, no link in a 3-link/PHB ever has to resist a lot of both lateral and longitudinal loads simultaneously. IOW, each link need only do one job.

This is not the case with the sharply converging uppers in a triangulated 4-link, never mind that this normally locates the rear roll center several inches higher than where it should be and results in too much axle roll steer in the vehicle understeer direction.

The T4L may have some advantages when it comes to packaging it all (but not always, if your car did not start life that way).


You might want to follow Ford's lead in this - the rear suspension was swapped from the T4L that had been in the Fox/SN95 Mustangs for 25 years to a 3-link with PHB in the S197 cars.

Sam Strano stepped out of F-bodies and into a S197 in 2007 and won F-Stock at the SCCA Solo Nationals by a convincing margin. This year is starting to look like more of the same.

My avatar car is a T4L and I can tell you that while it's OK with doing 'sweepers' and most on-ramps, it doesn't like slaloms at autocross at all.

I'm a little bit biased toward the 3-link, but the handling advantages seemed pretty clear when they first started getting discussed (elsewhere, ~7 years ago). Anyway, I put some money where my keyboard is (hope the link works - I can't get pictures back on my work computer to verify it), though there aren't enough miles on it to be leaning on it much. I do know that the S197 turns in much more crisply in assembly-line-stock condition than the avatar car ever has. Even though the two cars are very close in terms of weight, weight distribution, and wheelbase, and run on wheels of the same width.


Norm

parsonsj
03-26-2008, 04:27 AM
The 3 link only suffers a couple of minor disadvantages to the T4L.
1. The upper link gets into the rear seat area. If you are doing a rear seat, you'll need to go with buckets of some sort.
2. The Panhard or Watts location device can make exhaust routing more difficult.

That being said, if you are choosing between two Morrison products (for which you should be commended), I'd choose the 3 link from now til doomsday. It's just better.

jp

CraigMorrison
03-26-2008, 05:55 AM
What are you going to do with your car? Mainly for the street or mainly a track-day car?

If it is going to be 90%-95% on the street, the tri4 bar will work great for you. We have 7500 miles on our 55 that has it and our 60 Corvette has it too (1.05 skid, and fastest slalom ever tested at source interlink)

If you are building a track-day car, I would say go with the 3-link.

If you aren't going to do this project for a bit, sometime this year we are going to test Matt's 69 Camaro that has the mounts for a 3-link and tri4 bar. Both suspensions will be tested back to back with all other things the same. Should be a great tech piece.

CraigMorrison
03-26-2008, 06:05 AM
If you are going to be at the Pleasanton GG show this weekend stop by and you can have a chance to see both suspensions up close. We are going to have one of our tri5 chassis with the tri4 bar and a MaxG chassis with a 3-link.

parsonsj
03-26-2008, 06:24 AM
If you aren't going to do this project for a bit, sometime this year we are going to test Matt's 69 Camaro that has the mounts for a 3-link and tri4 bar. Both suspensions will be tested back to back with all other things the same. Should be a great tech piece.Hell yeah, it will! More good stuff. Thanks Craig.

jp

gt1guy
03-26-2008, 10:04 AM
Norm,
You got it! Keep me posted on the mods.

Kevin

Young Gun
03-26-2008, 03:17 PM
The 3 link only suffers a couple of minor disadvantages to the T4L.
1. The upper link gets into the rear seat area. If you are doing a rear seat, you'll need to go with buckets of some sort.
2. The Panhard or Watts location device can make exhaust routing more difficult.

That being said, if you are choosing between two Morrison products (for which you should be commended), I'd choose the 3 link from now til doomsday. It's just better.

jp

well the rear seat is a non-issue, we are putting in a cage, so the rear seat is not going to be usable any ways, so I can live with that. As far as exhaust routing, does anybody have examples of what can be done to route the exhaust? IIMuch was actually a huge inspiration in my project... I chose Morrison since I want NoGo to be one of the sickest 3rd gens out there, and I need a top notch suspension for that! anybody know what BP runs out back?

dipren443
03-26-2008, 06:38 PM
well the rear seat is a non-issue, we are putting in a cage, so the rear seat is not going to be usable any ways, so I can live with that. As far as exhaust routing, does anybody have examples of what can be done to route the exhaust? IIMuch was actually a huge inspiration in my project... I chose Morrison since I want NoGo to be one of the sickest 3rd gens out there, and I need a top notch suspension for that! anybody know what BP runs out back?

BP as in Bad Penny??? If so, Penny is running the Lateral Dynamics 3 link.

Young Gun
03-27-2008, 08:56 AM
BP as in Bad Penny??? If so, Penny is running the Lateral Dynamics 3 link.

yah thats what I mean, my bad, thanks for the info!

James OLC
03-27-2008, 02:35 PM
redundant post sorry