Hey drag race guys...... - Great Lakes 4x4. The largest offroad forum in the Midwest

Go Back   Great Lakes 4x4. The largest offroad forum in the Midwest > 4x4 Talk > General Tech
GL4x4 Live! GL4x4 Casino

greatlakes4x4.com is the premier Great Lakes 4x4 Forum on the internet. Registered Users do not see the above ads.
Search
Reply
 
Thread Tools Search this Thread
Old March 27th, 2010, 11:37 AM   #1
Nuggets
I fix stuff!
 
Nuggets's Avatar
 
Join Date: 09-15-06
Location: Bay City, MI
Posts: 13,445
iTrader: (13)
Mentioned: 3 Post(s)
Default Hey drag race guys......

I built a 4 link rear suspension for my Honda project and I'm confused about something. The axle goes up and down without issue but it does not articulate worth a shit. I asked somebody at a speed shop about this and they said that he thinks it is supposed to be that way in order to hold the car flat (no twist) during a launch.

Here's my roughed in setup:



Frame will probably set somewhat lower in the final setup. I need to load the front suspension before I set the ride height of the rear.

I don't see any obvious binding or interference. If this style suspension set up is not supposed to flex then I'm on my way to the next fabrication issue.
Nuggets is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old March 27th, 2010, 11:45 AM   #2
jeepnxj96
Senior Member
 
jeepnxj96's Avatar
 
Join Date: 10-16-07
Location: Allegan,Mi
Posts: 2,982
iTrader: (10)
Mentioned: 1 Post(s)
Default

why would you care if it flexed??? You want to eliminate as much twist as possible, the more twist you have, the less torque and power that is translated to the ground.

basically it is like running short arms on a lifted jeep, they only move so far in opposite directions of each other before binding up.
jeepnxj96 is offline   Reply With Quote
Old March 27th, 2010, 11:49 AM   #3
Nuggets
I fix stuff!
 
Nuggets's Avatar
 
Join Date: 09-15-06
Location: Bay City, MI
Posts: 13,445
iTrader: (13)
Mentioned: 3 Post(s)
Default

Quote:
Originally Posted by jeepnxj96 View Post
why would you care if it flexed??? You want to eliminate as much twist as possible, the more twist you have, the less torque and power that is translated to the ground.

basically it is like running short arms on a lifted jeep, they only move so far in opposite directions of each other before binding up.
I really don't care if it flexes. I just want to be sure that this is a trait of this type of suspension before I move on. In other words, I want to make sure I don't have a problem that could lead to failure.
Nuggets is offline   Reply With Quote
Old March 27th, 2010, 11:52 AM   #4
firehawk
Live Action!
 
firehawk's Avatar
 
Join Date: 10-02-07
Location: Clawson, Michigan
Posts: 12,771
iTrader: (43)
Mentioned: 19 Post(s)
Default

You are still gonna need a panhard bar, right?

Otherwise I think it will be fine.
firehawk is offline   Reply With Quote
Old March 27th, 2010, 11:55 AM   #5
Nuggets
I fix stuff!
 
Nuggets's Avatar
 
Join Date: 09-15-06
Location: Bay City, MI
Posts: 13,445
iTrader: (13)
Mentioned: 3 Post(s)
Default

Quote:
Originally Posted by firehawk View Post
You are still gonna need a panhard bar, right?

Otherwise I think it will be fine.
Yep. Gotta fab one up but I'm waiting to set ride height before setting up the panhard bar. I want to get it as close to horizontal as I can at ride height.
Nuggets is offline   Reply With Quote
Old March 27th, 2010, 11:56 AM   #6
firehawk
Live Action!
 
firehawk's Avatar
 
Join Date: 10-02-07
Location: Clawson, Michigan
Posts: 12,771
iTrader: (43)
Mentioned: 19 Post(s)
Default

Quote:
Originally Posted by Nuggets View Post
Yep. Gotta fab one up but I'm waiting to set ride height before setting up the panhard bar. I want to get it as close to horizontal as I can at ride height.


Gotcha
firehawk is offline   Reply With Quote
Old March 27th, 2010, 12:46 PM   #7
Bishop
Senior Member
 
Bishop's Avatar
 
Join Date: 04-12-07
Location: brighton, atlanta, MI
Posts: 3,590
iTrader: (15)
Mentioned: 0 Post(s)
Send a message via AIM to Bishop
Default

I don't know a lot about drag racing, but just from looking at the pic it looks like the reason it will not flex is due to a couple things.

the length of the arms. and the distance between the right set of arms and the left set.
I'm not sure how wide the finished product will be but if it is wider it will seem to flex better just due to the leverage, seeing how the arms are right at the pig.

So to me that looks fine and is doing its job it is set up for.

Last edited by Bishop; March 27th, 2010 at 01:03 PM.
Bishop is offline   Reply With Quote
Old March 27th, 2010, 01:09 PM   #8
Nuggets
I fix stuff!
 
Nuggets's Avatar
 
Join Date: 09-15-06
Location: Bay City, MI
Posts: 13,445
iTrader: (13)
Mentioned: 3 Post(s)
Default

Quote:
Originally Posted by Bishop View Post
I don't know a lot about drag racing, but just from looking at the pic it looks like the reason it will not flex is due to a couple things.

the length of the arms. and the distance between the right set of arms and the left set.
I'm not sure how wide the finished product will be but if it is wider it will seem to flex better just due to the leverage, seeing how the arms are right at the pig.

So to me that looks fine and is doing its job it is set up for.
I think it will not flex because the axle wants to rotate as it flexes. When you lift one side, the other will not allow the axle to rotate thus eliminating flex.

The car will be street driven so my concern is tearing up the rear suspension should I hit a pothole, turn into a steep driveway, etc. If the design of the suspension is robust enough to take the stresses of potholes, etc., I'm not concerned.
Nuggets is offline   Reply With Quote
Old March 27th, 2010, 01:33 PM   #9
95geo
newbie
 
95geo's Avatar
 
Join Date: 11-05-05
Location: dryden
Posts: 5,777
iTrader: (6)
Mentioned: 0 Post(s)
Default

It doesnt flex because you have restricted that range of motion out of it. The parallel 4 link allows wor up and down and side to side but no twist. That's why all vehicles with that suspension use rubber bushing, it allows for the needed deflection. Theres a couple things you can do but none of them leave you with a setup as rigid as you currently have it.

Take one link out and it'll be entirely freed up. I'd look into a rubber joint somewhere to give it a little bit of movement. Upper links are better for rubber than lowers on what you're working with.

If you made the links longer (6" or so) it'll help and also if you move the frame side mounts together. It'll still bind but you'll have more leverage on what's there.

For starters move each link one bolt closer to one another and see if that helps. You might just be stuck having to run rubber or poly mounts to allow a little deflection.

Get the track bar in there too.
95geo is offline   Reply With Quote
Old March 27th, 2010, 01:34 PM   #10
95geo
newbie
 
95geo's Avatar
 
Join Date: 11-05-05
Location: dryden
Posts: 5,777
iTrader: (6)
Mentioned: 0 Post(s)
Default

If you put the uppers at the top ish of the diff you can probably get some flex and remove the track bar too..... Just an idea.
95geo is offline   Reply With Quote
Old March 27th, 2010, 05:31 PM   #11
Nuggets
I fix stuff!
 
Nuggets's Avatar
 
Join Date: 09-15-06
Location: Bay City, MI
Posts: 13,445
iTrader: (13)
Mentioned: 3 Post(s)
Default

Good information 95geo. I've never delt with this type of suspension so I am not sure what I'm dealing with.

As far as bar length, I'm stuck with it. The total wheelbase of the car is supposed to be 79 inches but I stretched it to 80 just to give me a tad more length for my driveshaft.

Once again, I can live without much flex if that is the way the suspension will be. I just wanted to get some input from people that have delt with this type of suspension before.
Nuggets is offline   Reply With Quote
Old March 27th, 2010, 05:38 PM   #12
Bishop
Senior Member
 
Bishop's Avatar
 
Join Date: 04-12-07
Location: brighton, atlanta, MI
Posts: 3,590
iTrader: (15)
Mentioned: 0 Post(s)
Send a message via AIM to Bishop
Default

Well how much does the front travel?

If it has decent amount of travel, you would think that the front would pick up the slack from the rear when pulling into driveways and such. if that's all you are worried about.
Just like a Hi-Low.
Bishop is offline   Reply With Quote
Old March 27th, 2010, 05:43 PM   #13
mboies
BS MUDDERZ
 
mboies's Avatar
 
Join Date: 12-28-08
Location: Quincy, Mi
Posts: 507
iTrader: (1)
Mentioned: 0 Post(s)
Default

Quote:
Originally Posted by Bishop View Post
Well how much does the front travel?

If it has decent amount of travel, you would think that the front would pick up the slack from the rear when pulling into driveways and such. if that's all you are worried about.
Just like a Hi-Low.
thats similar to how a tractor is set up to. If the front moves then the rear will be fine hopefully.
mboies is offline   Reply With Quote
Old March 27th, 2010, 05:55 PM   #14
Nuggets
I fix stuff!
 
Nuggets's Avatar
 
Join Date: 09-15-06
Location: Bay City, MI
Posts: 13,445
iTrader: (13)
Mentioned: 3 Post(s)
Default

Quote:
Originally Posted by Bishop View Post
Well how much does the front travel?

If it has decent amount of travel, you would think that the front would pick up the slack from the rear when pulling into driveways and such. if that's all you are worried about.
Just like a Hi-Low.
The front is a narrowed Pinto suspension. I think that will have plenty of flex.
Nuggets is offline   Reply With Quote
Old March 27th, 2010, 08:36 PM   #15
pitbull2332
Senior Member
 
pitbull2332's Avatar
 
Join Date: 02-02-09
Location: scotts,mi
Posts: 1,166
iTrader: (28)
Mentioned: 0 Post(s)
Default

The 4 link bars are susposed to be 20"-22" in length to work best. I know you are limited in your frame to do that. the longer bars will give you more flex. I would run a wisbone setup on any 4 link setup. Less binding and easier to setup. I have changed my old car to a wishbone setup, And built the new car with one with great results. The suspension is a lot more free moving/less binding.
pitbull2332 is offline   Reply With Quote
Old March 27th, 2010, 09:00 PM   #16
Nuggets
I fix stuff!
 
Nuggets's Avatar
 
Join Date: 09-15-06
Location: Bay City, MI
Posts: 13,445
iTrader: (13)
Mentioned: 3 Post(s)
Default

I'm looking for somebody to tell me that this type of suspension does not have much flex to it.
Nuggets is offline   Reply With Quote
Old March 27th, 2010, 09:14 PM   #17
jeepnxj96
Senior Member
 
jeepnxj96's Avatar
 
Join Date: 10-16-07
Location: Allegan,Mi
Posts: 2,982
iTrader: (10)
Mentioned: 1 Post(s)
Default

Quote:
Originally Posted by Nuggets View Post
I'm looking for somebody to tell me that this type of suspension does not have much flex to it.
no flex in that suspension ??????
jeepnxj96 is offline   Reply With Quote
Old March 27th, 2010, 09:59 PM   #18
bacongrease
Am i still a Noob?
 
bacongrease's Avatar
 
Join Date: 08-28-08
Location: Troy/MI
Posts: 538
iTrader: (8)
Mentioned: 0 Post(s)
Default

arent most drag suspension designed for zero chasis yaw, which is what you would get with parallel links or a wishbone style? "flex" isnt really a characteristic that matters as long as you can cycle without binding or limit the cycle to when it binds.



this setup is alot like yours, except they are using a diagonal link to center the axle instead of a track bar running parallel to the housing, which is probably due how short a track bar will be when using such a narrow frame and shortened tubes.

i think what you have should work, links might be a little short, but the worst thing i see that causing is your anti squat to change more as your suspension moves, which probably wont be very much
bacongrease is offline   Reply With Quote
Old March 28th, 2010, 11:08 AM   #19
95geo
newbie
 
95geo's Avatar
 
Join Date: 11-05-05
Location: dryden
Posts: 5,777
iTrader: (6)
Mentioned: 0 Post(s)
Default

Quote:
Originally Posted by Nuggets View Post
I'm looking for somebody to tell me that this type of suspension does not have much flex to it.
It binds in that range of travel, that means it doesnt have flex.

Take one link out and it'll all make sense.
95geo is offline   Reply With Quote
Old March 28th, 2010, 11:41 AM   #20
firehawk
Live Action!
 
firehawk's Avatar
 
Join Date: 10-02-07
Location: Clawson, Michigan
Posts: 12,771
iTrader: (43)
Mentioned: 19 Post(s)
Default

I would think you don't want it to flex but if you do then 95geo told you how.
firehawk is offline   Reply With Quote
Reply
Great Lakes 4x4. The largest offroad forum in the Midwest > 4x4 Talk > General Tech

Thread Tools Search this Thread
Search this Thread:

Advanced Search

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 -5. The time now is 02:11 AM.


Powered by: vBulletin, Copyright 2000 - 2012, Jelsoft Enterprises Ltd.
User Alert System provided by Advanced User Tagging (Lite) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd. Runs best on HiVelocity Hosting.
Page generated in 0.29563 seconds with 80 queries