Rotary Drag Racing The place to post your racing stories and info

Let's talk IRS set up

Thread Tools
 
Search this Thread
 
Old Sep 2, 2012 | 05:25 PM
  #1  
sk8world's Avatar
Thread Starter
Chasing numbers
Tenured Member 20 Years
iTrader: (5)
 
Joined: Apr 2001
Posts: 5,097
Likes: 4
From: Alabama
Let's talk IRS set up

so I have tried many combos and some worked some were way off. I have been waiting for a Set of hks drag coil overs to come up for sale but no luck. I have been 90% happy with the way the stock touring rear springs and struts work. The 2 issues I have is, they sit too high and the are a tad soft. I feel like I bottom out just a tad. Maybe 25lbs harder would be perfect.

I have used koni yellows with stiffer springs, stockers in rear with stiff coil overs in front and my jic's that are way to stiff.

My stock set up was pretty consistent to 1.3's - low 1.4's on a good track... Good enough fo me..

Just can't take the jacked up redneck look.

So I called jic about converting these stiff coil overs to a drag coil over. We discussed what all would be needed and I decided I would just try myself. Had them deflated to 80psi in the cylinders. Ordered some 8 inch 200lb springs. Installed and it just went to the ground. I had to almost preload the entire spring to get the car to a usable height. So I ordered some 225 springs and added 2 inches (10 inch) I had to preload these (compress the spring) about 2 inches and it sits perfect. I was going to go Friday night to test but ended up running out of time.

My thought are the preloaded springs are going to want to raise the rear too fast or make it bouncy?

I think I may be trying something that just won't work.

Now on to the front.. I have just been using my stiff jic's on the hardest setting. I was reading some last night on a drag chassis set up and it said the front would rise faster on softer springs and less dampening setting? I don't see how but sure I am wrong. I would think you would want to preload the **** out of the front so it would rise fast and have a stiff spring-damping to keep the front up and rear plante?

The rear I would think a double adjustable strut with correct spring weight to allow the rear to squat quick without bottoming out then have the dampening on the rising side set so it rises very slow the entire pass?

Educate me please!
Reply
Old Sep 2, 2012 | 10:55 PM
  #2  
ultimatejay's Avatar
Eats, Sleeps, Dreams Rotary
Tenured Member 10 Years
iTrader: (1)
 
Joined: Nov 2006
Posts: 4,148
Likes: 4
From: California
You'll be hard pressed to run better than 1.3x 60ft on an IRS small tire. I would just leave it and work on shifting and making more power
Reply
Old Sep 2, 2012 | 11:23 PM
  #3  
sk8world's Avatar
Thread Starter
Chasing numbers
Tenured Member 20 Years
iTrader: (5)
 
Joined: Apr 2001
Posts: 5,097
Likes: 4
From: Alabama
Originally Posted by ultimatejay
You'll be hard pressed to run better than 1.3x 60ft on an IRS small tire. I would just leave it and work on shifting and making more power
I 100% agree. Just want a lower stance. Got to look good!

Btw.. I got the shifting dead on with my combo. More power may come later but I have a goal to run 9's on current 67mm turbo, via Mazda driveline, axles, etc...
Reply
Old Sep 3, 2012 | 03:26 AM
  #4  
C. Ludwig's Avatar
www.lms-efi.com
Tenured Member: 25 Years
Liked
Loved
iTrader: (27)
 
Joined: Mar 2001
Posts: 5,269
Likes: 147
From: Floyds Knobs. IN
Originally Posted by sk8world
The rear I would think a double adjustable strut with correct spring weight to allow the rear to squat quick without bottoming out then have the dampening on the rising side set so it rises very slow the entire pass?

This, but front and rear. The spring keeps the car off the ground. The damper controls the motion. If you still have your Konis, I would suggest talking to them about converting then to double adjustable and custom valving them for your purpose. They sell a coil over sleeve for the 42mm body shocks made for the FD so you can go to a custom spring.
Reply
Old Sep 3, 2012 | 08:19 AM
  #5  
sk8world's Avatar
Thread Starter
Chasing numbers
Tenured Member 20 Years
iTrader: (5)
 
Joined: Apr 2001
Posts: 5,097
Likes: 4
From: Alabama
Originally Posted by C. Ludwig
This, but front and rear. The spring keeps the car off the ground. The damper controls the motion. If you still have your Konis, I would suggest talking to them about converting then to double adjustable and custom valving them for your purpose. They sell a coil over sleeve for the 42mm body shocks made for the FD so you can go to a custom spring.

Sold them. I have spoken to koni before on this. After I just decided to pick up some hks drag shocks but it's been hard to find them.
Reply
Old Sep 3, 2012 | 08:45 AM
  #6  
C. Ludwig's Avatar
www.lms-efi.com
Tenured Member: 25 Years
Liked
Loved
iTrader: (27)
 
Joined: Mar 2001
Posts: 5,269
Likes: 147
From: Floyds Knobs. IN
Would be nice if a guy could adapt some Afcos, or something similar. Would probably be cost effective to do the fab work to use a true drag shock versus reworking a Koni or similar.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
trickster
2nd Generation Specific (1986-1992)
25
Jul 1, 2023 04:40 PM
streetlegal?
New Member RX-7 Technical
13
Mar 17, 2022 02:46 PM
matty
Suspension/Wheels/Tires/Brakes
12
Jan 18, 2020 10:39 AM




All times are GMT -5. The time now is 04:37 AM.