Launch Suspension

3ponyshow

Founding Member
Jun 26, 2002
319
1
18
Las Vegas
I'm researching possible options to improve my launch at the strip and I noticed that quite a bit has changed in the theory of weight transfer since even just a few years ago. There seems to be very little regarding SN95's anymore and I don't want to assume principles for S197's are the same as ours. If anyone has some good general information or articles they could point me to, I'd appreciate it.
 
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start with the basics... get a good LCA like MM Extreme duty LCA...Uppers are also preferred when drag racing.. do you already have springs? if so what kind? a launch spring will obviously be the one to get if not... then find yourself a nice set of MT ET's or a really meaty DR... that would be a good start a nice set of drag shocks/struts will help you out as well...

im a road course guy but that should help you get started
 
start with the basics... get a good LCA like MM Extreme duty LCA...Uppers are also preferred when drag racing.. do you already have springs? if so what kind? a launch spring will obviously be the one to get if not... then find yourself a nice set of MT ET's or a really meaty DR... that would be a good start a nice set of drag shocks/struts will help you out as well...

im a road course guy but that should help you get started

+1 a call to Maximum Motorsports may be in order. They sell a Street & Strip Box that contains SFC's, MM adjustable LCA's & FRPP HD UCA's, soft springs, CC plates, and adjustable tokico drag shocks. That would cover the basics...
 
What is your combination at the strip now? What are your 60' goals? These are huge factors to determine what you need.

Mustangs have a reasonably good drag race suspension from the factory, but you need sticky tires to do anything. My stang has gone 1.7 60' times with just nitto drag radials and a removed front sway bar. With slicks, 1.6's should be no problem for a mustang with the power and gearing to make it happen.

If you really are serious about it, here is a series of 3 articles with very simple modifications that will let you go 1.4 60' times: Making Your Mustang Hook, Part 1
 
Thanks for the feedback, guys!
What I'm looking for is the best launch I can get while keeping the car safe and reliable. I had the car at 420+ to the rear wheels but backed it off because it was too much for the rest of the drive train. Balance is the key. I have plenty of hp to get into the deep 12's and want to focus more on weight reduction, weight transfer and suspension. That's why I'm trying to learn as much as I can to make the best choice for my application.

I have a stock auto with 2500 stall and shift kit, stock 28 spline rear, Koni yellows (5 way adjustable) with sport springs that I run on the softest setting to launch, MM full length sub frames, Nitto 315's 555R's (20 lbs) and putting 361/365 to the rear tires. My best 60' is 2.00 flat that I ran on 275's. I haven't tried the 315's yet, but I broke the 275's loose even after melting the hell out of 'em.

I already wrote to MM but haven't gotten a response yet. I also sent a request off to Koni requesting more detail on each setting, but nothing there either.

I understand (I think) what CC plates do, but don't understand how they benefit a launch?
What is the advantage of removing the from sway bar?
How high could I launch with a line lock without ripping everything apart?

bhuff30, thanks for the articles!
 
With the NT 555 (non R) I've had the best luck with street PSI (32 or whatever they are I forget) and no burnout (just a quick spin to kick the rocks off).

I don't have any of the fancy suspension stuff, but I've got tokico blues front and rear, stock rear springs, and UPR K and Coils up front at 14 175 I think.

Any way best launch I've got is a high 1.9 60'. Every time I tried doing burnouts or messing with PSI my 60' has stayed in the 2.0 to 2.2 area. Granted the track I go to has questionable prep on the line, but I think with a better driver and near street PSI you could get low 1.9s or even high 1.8's on my setup.

I thought alot of people run the 555Rs in the 15-18 psi range? 20 seems a bit high as does your 60' with DRs.

What I'm getting at is you should have better 60's than I am on my setup.

Are you driving around the box and then backing into the water? Have you played with your launch RPMs? You have most of the intermediate pieces for a good launch, I would expect you to be able to net 1.8s at least?

I'm still new to the suspension side of things at the track so I could be way off base.

*EDIT* CC plates will just align your wheels more accurately if you dropped the front at all. Unless you have coil overs I'm not sure that you would benefit from them as drag cars typically aren't lowered much?
 
Was the 275 you were running before the 555R or just a street tire? I couldn't really tell from your post.

What kind of blower do you have? If you have a centrifigual blower, then it can be a lot more difficult to get into boost in the 60', requiring a looser converter and/or steeper gears.

With the 555R, you shouldn't have much of a traction problem. You do need to get them nice and hot though. When you do the burn out, burn them HARD and make a big'ol smoke show. Just when you think they are hot, go a little longer. This tire likes to be hot. I run 18-20psi in my nittos, but didn't notice much gain going lower. Going higher, I tend to spin a little more. When you launch on the nitto, you have to launch a little more carefully. It might help to pre-load the drivetrain, by holding the engine against the brakes, maybe to 2000rpm. Then, roll onto the gas on the green light, to get a smooth start. Shocking the driveline will cause tire spin, especially on the 555R.

I suggest practicing your launch and making that work well before playing with the suspension... but to answer some of your suspension questions: CC plates are simply for allowing better alignment of your car, especially if it is lowered. Thus, it isn't useful to improve your drag times. Removing the front sway bar helps the front end lift up, and improve weight transfer. You can just disconnect it at the track for most of the benefit, but taking 35lbs off the nose helps a lot too. ;). Set your front shocks to the softest setting, and your rear shocks to the firmest setting. More firm in the rear will help prevent the back from bottoming out, and softer in the front helps the front end rise.

I think the main thing, will be to work on your launch technique. You can not shock load the 555R. Make a gentle smooth launch, and if you can break them loose by slowly rolling on the gas, I would be shocked. With my 245 width nittos, I've gone quite a few hp limited, high 1.7 60' times.
 
myponyrocks said:
What I'm getting at is you should have better 60's than I am on my setup.

You're right. I'm sure the 2.0 60' has something to do with the quality of driver. :rolleyes: If you're way off base, you still clearly have a better understanding than I do.

To clarify, I've always run the Nitto 555R's. The 275's are what I was braking loose. I've tried several different combinations of psi (20-32), I tried launching from idle (500 rpm) up to 2300 rpm brake load (max with my TC) and just can't find that sweet spot. I do smoke 'em up though. (See avatar) That's why I went with the wider Nitto' s.

A key point you mentioned is the shock load to the rear tires. Clearly that is a consistent (bad) symptom of what's wrong. That's why I thought it would be a good idea to have a better understanding of effective weight transfer (which my record supports a complete misunderstanding on my part) and weight reduction. As for the weight reduction, I know that's always beneficial, but there's always an associated cost also. A K-member is an idea, but from what I understand, I'd have to change my Koni setup for coil overs. Loosing the front sway bar sounds like a possible idea, but how does that affect driveability both on the track and off?

Thanks for spending the time on this guys! Everything I learn brings me one step closer.
 
I cut consistent 1.8's on my set up. Minor bolt ons, shifter, 4.10's, line loc and the old Nitto drag radials at about 30-34 psi, depending on the weather and track prep for the night. That's at Orlando Speed World. I havn't raced since I have moved to MI.
 
A K-member is an idea, but from what I understand, I'd have to change my Koni setup for coil overs.

The UPR K Kit is a pretty good deal comes with springs and everything. Pretty sure you'd still be able to use your struts, then just throw the springs on fleabay. It's a pretty big wieght difference amd the front is a good place to go on a diet :)
 
yes the konis you have can handle a pretty high spring rate if you decide to go coilover so that will save you some change in that dept :nice:

like i said before im an open track guy, but i doubt you'll have to go with a high enough spring rate that will make you have to change shocks/struts..i could be wrong there :shrug:
 
I cut consistent 1.8's on my set up. Minor bolt ons, shifter, 4.10's, line loc and the old Nitto drag radials at about 30-34 psi, depending on the weather and track prep for the night. That's at Orlando Speed World. I havn't raced since I have moved to MI.

What RPM do you launch at?
What size are your DR?

Some good info in here. I just recently got a set of 275 Hoosier DR. Pre-loading with the line lock around 2500-3000 rpm and cutting a 2.10 60'.

I kept lowering my psi at the track after each pass and it lowered my 60'. I ended up around 18psi.
 
You should get a set if track only wheels and put a full slick on them and quit messing with radials. I launch at 5600 on stock suspension and cut mid 1.6s all day

I've been tempted to make changes like that, but again I'm not looking to cut 60's at all costs. I'm looking for the most efficient lauch to match my application. I want the car at the strip to be the same car at the street light. No mods for the sole purpose of et's.

Alot of the feedback I've gotten so far has identified several things I could do differently and changes I could make without substantially sacrificing driveablity.
 
What RPM do you launch at?
What size are your DR?

Some good info in here. I just recently got a set of 275 Hoosier DR. Pre-loading with the line lock around 2500-3000 rpm and cutting a 2.10 60'.

I kept lowering my psi at the track after each pass and it lowered my 60'. I ended up around 18psi.

275's and I launch anywhere between 3000 and 4500 rpm's, again, depending on the track prep for the night. Orlando speed world really sucks. Once I can afford to start driving my car again the Nitto's are going to be used for street use and I am going to get some better tires. I find that they are really inconsistent.