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SCrazy
08-29-2011, 08:45 PM
Alot of the stock suspension cars really squat at launch, mine is pretty extreme. I have vogtland springs and Koni shocks that are adjusted full firm but the car still rotates alot on launch.

Is there something short of new springs & shocks that can be done to get this under control?

XR7 Dave
08-29-2011, 09:18 PM
Do you have the fronts on full firm also?

rzimmerl
08-29-2011, 09:40 PM
Do you have air bags, are the bushings all stock?

Kevin Leitem
08-29-2011, 10:31 PM
Alot of the stock suspension cars really squat at launch, mine is pretty extreme. I have vogtland springs and Koni shocks that are adjusted full firm but the car still rotates alot on launch.

Is there something short of new springs & shocks that can be done to get this under control?

drop it off at my place after the shootout and it will quit doing that

VicRattlehead
08-30-2011, 12:02 AM
whats the tire doing? if its planting and bouncing up thats not good. got any video?

SCrazy
08-30-2011, 08:28 AM
The attached picture is typical of what I'm talking about....looks as though the rear suspension is bottoming out. I don't think the wheels bounce, I've not felt that anyway, and unfortunately I don't have a video that shows a good view of the launch.

Front and rear shocks are all set firm now although I think in this pic fronts were pretty soft.

Bushings have all been changed...MN12 performance kit from a few years ago

Somehow I knew Kevin's "ulimate" solution would rear it's head...someday maybe!!

Airbags??? Can I just chuck a couple of air bags in there and make this better?

Ira R.
08-30-2011, 09:00 AM
Mine does the same thing. Stock suspension all around.

That is a great picture Brian.

Ira

mellbutler
08-30-2011, 09:14 AM
about a month ago when I took my black car to the track it was doing the same thing, rebuilt stock but upgraded bushings...now my red car which is lowered 1.6in not so much. Suggest lowering with proper lowering springs...casue when I bought my red car it had cut springs and still had the squish they were just shorter. The lowering springs seem to be tighter, less flex therefor less squat. jmo:)

kenewagner
08-30-2011, 09:17 AM
That is a great picture Brian.

Ira


I agree. If i had a picture of mine doing that I would frame it and hang it on the wall. Not being a die hard racer I would think that the rear dropping like that would be perfect as it looks to be planting the rubber right into the track rather than spinning and loosing traction. Just my thought

Ken

Ira R.
08-30-2011, 12:49 PM
I agree. If i had a picture of mine doing that I would frame it and hang it on the wall. Not being a die hard racer I would think that the rear dropping like that would be perfect as it looks to be planting the rubber right into the track rather than spinning and loosing traction. Just my thought

Ken

You mean like these? Speak with Sally, the godlike woman with the camera :)


http://i112.photobucket.com/albums/n161/irar_6971081/Shoot%20Out%202009/DSC_0186-1.jpg


http://i112.photobucket.com/albums/n161/irar_6971081/Shoot%20Out%202009/DSC_0110.jpg

seawalkersee
08-30-2011, 01:06 PM
THere does appear to be a difference in the two pix of the cars. One of Brian's car showing the suspension at (what appears to be) full travel, and Ira's is close but I think there is a bit left. Only way to measure that would be to raise the front end and see what the difference is in the drop.

So to answer your question for the suspension; Once the front end is that high, a majority of the weight is now put on the rear suspension. Without going to a stiffer spring (pretty sure you do not want that on the rear of an IRS car) or to put air bags in. The suspension can only handle so much weight and that is actually increased over the weight (its actually force) as the vehicle takes off since the rear end is trying to climb under the car towards the front.

So...go on a diet or add some air bags would be my suggestion. However, what is the problem with what is happening? Are you getting too much bite right of the line and causing a bog or are you just concerned about the way it looks?

SWS

ganuolfthegrey
08-30-2011, 01:33 PM
you turbo guys are starting to sound like honda owners.

real men race from a dig. if you have to go from a roll. you can't drive for crap.

rzimmerl
08-30-2011, 01:36 PM
you turbo guys are starting to sound like honda owners.



I don't see any turbo guys posting in this thread:confused:

neverfastenough
08-30-2011, 01:48 PM
Our presence is just known, Ryan.

SCrazy
08-30-2011, 01:58 PM
what is the problem with what is happening? Are you getting too much bite right of the line and causing a bog or are you just concerned about the way it looks?

SWS

I guess my real concern is that my 60' times in this car are at VERY best high 1.6s. Car launches hard off a trans break and two step, sticks pretty well, weighs less than 3400#s. Maybe I'm expecting too much but I don't think so and I trying to figure out what's keeping the 60' times higher than I would like.

Seems like I'm burning energy rotating the car in lieu of pushing it here.

kenewagner
08-30-2011, 02:08 PM
I guess my real concern is that my 60' times in this car are at VERY best high 1.6s. Car launches hard off a trans break and two step, sticks pretty well, weighs less than 3400#s. Maybe I'm expecting too much but I don't think so and I trying to figure out what's keeping the 60' times higher than I would like.

Seems like I'm burning energy rotating the car in lieu of pushing it here.

It seems surprising to me as well. I am in the 1.6 range for 60 foot but the diffrence is my car weighs 3800 lbs without me in it. Sounds like you should be a little quicker not only in the 60 foot than me but overall ET as well. Less than a tenth of a second between us. Maybe your concern is justified

Ken

BLOWN38
08-30-2011, 02:30 PM
More stall, more gear, higher shift point? Tires screwed down? Mark the tire and see if its turning on the rim. I just screwed down the inside of mine and it seems to be working fine that way.

Do you have a data log we can look at? Sorry if I missed it in another thread. Your torque is kinda low in your sig. I have 440 torque at 4k and pull low 1.6's high 1.5's at about 3900lb race weight. Mine doesn't squat as much as yours in the pics I've seen. Stock shocks on firm and eibach springs.

SCrazy
08-30-2011, 02:44 PM
Chris:

Both data logs I posted in the "Tuning at the Track" thread were both high 1.6 60' launches.

Converter stalls at about 3800 and I've been launching at 3400 which has yielded the best results, gears are 3.73. Last year running around 12s I was trapping at a little over 6k rpm now at 11.6 I'm down around 5700....I might have room there for a gear change...not sure.

See now....it's 60' #s like this I hear from you and Ken that make me think I'm missing something.

I've not checked to see if the tires are slipping on the rim but I'll do that.

rzimmerl
08-30-2011, 03:06 PM
I pulled consistent high 1.6's at the shootout last year. With the trans brake and 2 step I'd expect you in the 1.5's with that converter for sure.

r429460
08-30-2011, 03:15 PM
If you are running lowering springs your car is probally bottoming out the rear suspension.
The front end lift can be limited. This gives a better reaction time, its also slows your 60'.
My guess get rid of the lowering springs.

SCrazy
08-30-2011, 03:16 PM
I pulled consistent high 1.6's at the shootout last year. With the trans brake and 2 step I'd expect you in the 1.5's with that converter for sure.

You guys are feeding my insanity here.

rzimmerl
08-30-2011, 03:27 PM
I can understand the frustration, as your car is well more setup then mine and Ken's. The factor that I can see is the torque, if you rule out the tires, and maybe the springs. I'll see if I can find the shots of my car launching last year, running 1.6" Vogtlands and KYB shocks. How much boost is it making off the 2 step?

Kurt K
08-30-2011, 03:37 PM
More stall, more gear, higher shift point? Tires screwed down? Mark the tire and see if its turning on the rim. I just screwed down the inside of mine and it seems to be working fine that way.

Do you have a data log we can look at? Sorry if I missed it in another thread. Your torque is kinda low in your sig. I have 440 torque at 4k and pull low 1.6's high 1.5's at about 3900lb race weight. Mine doesn't squat as much as yours in the pics I've seen. Stock shocks on firm and eibach springs.

My results are close to yours...low 1.6s to high 1.5s, and close to the same race weight, maybe even a bit heavier. I haven't screwed my tires and probably should be checking rotation.

What rpm do you try to leave at? I usually stall mine to 2800-3000 before the lights change and I leave. If I try to start at a lower rpm and let the converter flash, I get worse results usually caused by tire spin.

SCrazy
08-30-2011, 03:39 PM
Car is at about 16psi sitting on the rev limiter at launch...the vogtlands I have are the 3/4". I also have a set of 1.5" eibachs laying around somewhere but not sure if they would help or hurt.

Kurt K
08-30-2011, 03:45 PM
Car is at about 16psi sitting on the rev limiter at launch...the vogtlands I have are the 3/4". I also have a set of 1.5" eibachs laying around somewhere but not sure if they would help or hurt.
Duh!, forgot about the 2-step. How tall are your tires? forgive me if I missed it.

Edit: Wait a minute....I'll gladly help you after the Shootout ;) :D

rzimmerl
08-30-2011, 03:50 PM
Whats your 2 step set at if its on the rev limiter at launch? The way I understood your previous post is that it was at 3400:confused:

SCrazy
08-30-2011, 03:54 PM
Tires are 27".

I gotta find away to nail that 11.5 index so I have a shot against the fabled black car with white hood.

SCrazy
08-30-2011, 03:56 PM
Whats your 2 step set at if its on the rev limiter at launch? The way I understood your previous post is that it was at 3400:confused:

Yes, that right. Two step at 3400, Tq conv stall is 3800.

kenewagner
08-30-2011, 04:03 PM
Tires are 27".

I gotta find away to nail that 11.5 index so I have a shot against the fabled black car with white hood.

Your so mistaken;) My car is red:D

Ken

SCrazy
08-30-2011, 04:16 PM
Your so mistaken;) My car is red:D

Ken

You don't come strutting onto the track like Fonzarelli with the fancy "Track Champion" jacket on so I must admit I find Kurt more intimidating.

mellbutler
08-30-2011, 04:19 PM
our presence is just known, ryan.

omg lol!!!

Kurt K
08-30-2011, 04:27 PM
Tires are 27".

I gotta find away to nail that 11.5 index so I have a shot against the fabled black car with white hood.

Hmm, mine tires are 27" also.

btw, it is a gray hood:p

David Neibert
08-30-2011, 04:33 PM
Brian,

From looking at the picture I would have thought your 60ft times were in the 1.5s and I've always been dissapointed that mine doesn't squat that low coming off the line. I think Chris might be right about the tire slipping on the wheel. Easiest way to reduce the squatting would be to add air bags.

I was pulling high to mid 1.6s last year launching from 1800 rpms with no boost, on a 2800 stall converter with a heavier car and a pig rich tune. I'm expecting high to mid 1.5s with the new converter, 28" Hoosiers and a good tune.

BTW, I've got H&R springs, with air bags and stock shocks left on the auto setting.

David

nickleman60
08-30-2011, 04:46 PM
My last run down the track in Dec. 2010 netted me an 11.15 with a 1.53 60'. Car then weighed 3880 with me in it, 4.10 gears, 27" M/T slicks, 100 shot of nitrous off the line and launching at around 1100 rpm's. Car seems to squat pretty far but not as far as yours, I have stock suspension and Eibach springs.

This years unknowns in performance due to changes - 28" Hoosier slicks, rollbar added and relocated my nitrous nozzle location.

Pic is from 2010 Shootout, car has 28" tires on it.

BLOWN38
08-30-2011, 04:46 PM
I would get some 28" tires and some 4.10s. I'm on the foot brake to 2000 rpm not in boost. I wish I could get this WOT box to work how I would like. So I could come off the line in some boost.

I can almost gauruntee you are turning the tire on the rim. How much I don't know, but when I checked mine earlier this year they moved abour 2 inches in 5 passes. I would suspect yours to be worse with the 2 step and trans brake.

nickleman60
08-30-2011, 04:51 PM
our presence is just known, ryan.

yep...............for breaking...:rolleyes::D

SCrazy
08-30-2011, 07:26 PM
I can almost gauruntee you are turning the tire on the rim. How much I don't know, but when I checked mine earlier this year they moved abour 2 inches in 5 passes. I would suspect yours to be worse with the 2 step and trans brake.

Do you have tubes in your wheels, I do not, do you think I could just throw some screws in and not worry about this? Is a couple inches of slip enough to make the kind of difference we are talking about in this thread?

SCrazy
08-30-2011, 07:27 PM
I was pulling high to mid 1.6s last year launching from 1800 rpms with no boost, on a 2800 stall converter with a heavier car and a pig rich tune.

.....killing me.....

XR7 Dave
08-30-2011, 07:40 PM
Slap some air bags in there and experiment with pressure. Moving the tire a couple inches isn't costing you ET. Now if you were spinning in the rims, that would be a different story. Limiters on the front suspension would also help a lot.

SCrazy
08-30-2011, 08:00 PM
Slap some air bags in there and experiment with pressure. Moving the tire a couple inches isn't costing you ET. Now if you were spinning in the rims, that would be a different story. Limiters on the front suspension would also help a lot.

I'm a little concerned about running screws through my Holeshot drag wheels, I'm gonna contact Brad about it

I'm definately going to drop in some air bags....does anybody have the size handy...if not I'll go searching I'm sure it's here somewhere.

I've traded alot of info in this thread but interestingly there are no clear answers as to why my car 60 foots 0.1 to 0.2 seconds slower than everybody thinks it could be.

rzimmerl
08-30-2011, 08:06 PM
I've traded alot of info in this thread

Thats what this club is all about, share some info, talk some smack, and then show it on the track.

XR7 Dave
08-30-2011, 08:09 PM
You are getting way too much suspension movement and it is absorbing energy. Cars with less power, less converter, etc. don't rotate the chassis as far or as quickly and therefore put more energy into forward motion.

You get that thing to leave the line proper and it will be a lot quicker.

SCrazy
08-30-2011, 08:44 PM
You are getting way too much suspension movement and it is absorbing energy. Cars with less power, less converter, etc. don't rotate the chassis as far or as quickly and therefore put more energy into forward motion.

You get that thing to leave the line proper and it will be a lot quicker.

You see.....that's where this whole deal started three pages ago...and now we've bounced ideas (and BS) around and come right back to where things started. It was my original feeling going into this discussion that this could be the largest issue.

We are going to find out.....

SCrazy
08-30-2011, 08:45 PM
Thats what this club is all about, share some info, talk some smack, and then show it on the track.

Yup....I love this stuff

CurtisPaulfrey
08-30-2011, 09:08 PM
http://i35.photobucket.com/albums/d180/CurtisPaulfrey/SCRUN2.jpg

I'll put this up because I wanted to post with the cool kids

sts70004
08-30-2011, 09:15 PM
http://i35.photobucket.com/albums/d180/CurtisPaulfrey/SCRUN2.jpg

I'll put this up because I wanted to post with the cool kids

Whats goin on with the lip on the back bumper? Are you dragging it on launch?

racecougar
08-30-2011, 10:08 PM
I'm definately going to drop in some air bags....does anybody have the size handy...if not I'll go searching I'm sure it's here somewhere.

http://www.sccoa.com/forums/showpost.php?p=535997&postcount=20

BLOWN38
08-30-2011, 11:35 PM
The wheels I have now do not have tubes in them. One of them leak down slowly, not enough to affect a drag day. I screwed the inside down and the one still leaks down the other is fine. I only but 8 screws in.

Summit sells a kit with a plate to mark the holes. http://www.summitracing.com/parts/SUM-G1497-1/

David Neibert
08-31-2011, 12:47 AM
My last run down the track in Dec. 2010 netted me an 11.15 with a 1.53 60'. Car then weighed 3880 with me in it, 4.10 gears, 27" M/T slicks, 100 shot of nitrous off the line and launching at around 1100 rpm's. Car seems to squat pretty far but not as far as yours, I have stock suspension and Eibach springs.

This years unknowns in performance due to changes - 28" Hoosier slicks, rollbar added and relocated my nitrous nozzle location.

Pic is from 2010 Shootout, car has 28" tires on it.

Great picture Keith...do you still have the front sway bar attached ?

David

seawalkersee
08-31-2011, 01:58 AM
I'm a little concerned about running screws through my Holeshot drag wheels, I'm gonna contact Brad about it

I'm definately going to drop in some air bags....does anybody have the size handy...if not I'll go searching I'm sure it's here somewhere.

I've traded alot of info in this thread but interestingly there are no clear answers as to why my car 60 foots 0.1 to 0.2 seconds slower than everybody thinks it could be.

I actually have a set I will sell you if you want to shoot me a PM. I will dig them out tomorrow.

SWS

nickleman60
08-31-2011, 05:36 AM
Great picture Keith...do you still have the front sway bar attached ?

David

Yes it does, I was thinking of removing it since I'm not a road racer.....:rolleyes:

SCrazy
08-31-2011, 08:33 AM
http://www.sccoa.com/forums/showpost.php?p=535997&postcount=20



Summit sells a kit with a plate to mark the holes. http://www.summitracing.com/parts/SUM-G1497-1/



Thanks Rod & Chris

KYSal
08-31-2011, 10:41 PM
[QUOTE=Ira R.;956996]You mean like these? Speak with Sally, the godlike woman with the camera :)

Awe shucks Ira, you are too kind. ;)

CMac89
08-31-2011, 11:03 PM
I would suggest getting some good coil overs of some sort. I don't understand why people don't want to get something that you don't have full control over. There isn't a shock out there that is built to reflect your full expectations, without dual adjustment capability.

Surely Strange, AFCO, QA1, and so on, has something that would work. They do custom stuff every day.

VicRattlehead
08-31-2011, 11:24 PM
my qa1 in front full loose. the stock shocks in back are killing me, but h&r springs and airbags. 0 issues with traction 0 issues with wheelhop and still cuts 1.6 60' times with less hp/tq then anyone in this thread. leaves at 4k off the transbrake. my only issue is i need stiffer springs up front, need to put a limiter on there somehow and really need to do something about the crap rear shocks.

SCrazy
09-01-2011, 08:31 AM
I'm committed to installing Air Bags and I'm looking at different ways to do travel limiters in the front (strap or cable).

Question about the travel limiters...how do they effect the track of the car. Say one is a 1/4" longer than the other or something is this going to cause the car to pull to one side. What happens if one side stretches or fails is the car going to pull hard to one side or the other??

Since the front is coil over already am I just better off getting a proper set of shocks/springs?

XR7 Dave
09-01-2011, 08:49 AM
What Casey is talking about is a fully adjustable coil over that takes a universal spring which you can buy in a variety of spring rates. Will Smith has these on his car, I believe there are pictures somewhere. What this does is allows you to easily change spring rates up front and make them as stiff as you want all while adjusting the shocks for maximum control.

The Koni's are only adjustable on rebound. A fully adjustable shock will he adjustable separately on rebound and compression.

SCrazy
09-01-2011, 09:06 AM
What Casey is talking about is a fully adjustable coil over that takes a universal spring which you can buy in a variety of spring rates. Will Smith has these on his car, I believe there are pictures somewhere. What this does is allows you to easily change spring rates up front and make them as stiff as you want all while adjusting the shocks for maximum control.

The Koni's are only adjustable on rebound. A fully adjustable shock will he adjustable separately on rebound and compression.


Understood.....If I have a proper spring/shock combination I could control the front end without the use of a travel limiter...correct? Or am I missing somthing?

I don't think I have that option in the rear since coil overs would not be a simple bolt-on installation.

XR7 Dave
09-01-2011, 09:09 AM
The rear is more complicated. You won't be able to do coil overs in the rear but you might be able to use a Cobra double adjustable shock and then simulate stiffer springs with the air bags.

Front suspension travel is limited by shock piston length which may or may not be sufficient. Most drag racers still experiment with limiters because the shocks tend to extend too far unless they are specifically designed to limit travel.

CMac89
09-01-2011, 09:15 AM
You wouldn't need travel limiters with coil overs. You'll be controlling the rear-end's squat with the spring rate and the shock. Just by removing the stock, rear springs and switching to coil overs will get rid of most of the squatting right there. Moving the spring further outward from the fulcrum point of the lower control arm allows for more proportionate dampening of forces. It doesn't require a heavy spring to hold the car.

If your front shocks are full tight on extension, then they need re-valved or are insufficient valving for the car's weight. For these, you don't need a compression adjustment unless you are doing wheelstands. The compression adjustment, for the front, just allows for a smooth landing whenever coming off of a wheelstand. You can get single adjustable shocks, for the front. Are they steel cased or are they an aluminum body? If aluminum bodied, you can have them re-valved by any shock company.

As far as rear shocks go, I'm more than certain that they're the same as the Mustang shocks; only mounted differently, but that isn't a problem. The only thing that needs verified for that is the overall extended length. If someone knows the SC's extended length, then I can figure it out.

392Bird
09-01-2011, 10:04 AM
I had a very serious squating problem with mine. It was bad enough, that it showed in the rubber left from the rear tire, with it being narrower than it should be from camber changing during the squat. I added air bags to the rear springs, and with them set at 15 psi, the tires stay flat. I run QA1 coil overs in the front, and the rear camber set at "0". The air bags also allow you to tweak the suspension for level straight launches

I am thinking about putting a solid axle and mini tubing it over the Winter so I can go to some real rubber on it.

XR7 Dave
09-01-2011, 10:12 AM
Casey, I think you are talking a different language. He has stock shocks in front. They are Koni's but they are stock replacements. He does not have the coil overs you are thinking of.

On the rear, you can't install coil overs. Well, you could install them in the stock shock locations but that part of the body isn't strong enough to hold the whole car. It would require some significant remodeling. I was just suggesting that the use of a Cobra adjustable rear shock would help control squat along with airbags.

In the front he would have to convert to an aftermarket coil-over shock system. Which definitely can be done, but I think that the aftermarket stuff still may have too much travel and require a limiter. The type of shock housing and mounting etc. limits choices on which units can be used, or perhaps I should say "have been used".

seawalkersee
09-01-2011, 02:11 PM
Are your rear shocks factory style or are they aftermarkets? I have the factory cobra ones in the rear of my car. They are a good deal stiffer than the factory ones for the bird. Not sure if your car will overpower them or not.

SWS

VicRattlehead
09-01-2011, 02:20 PM
Dave

The double adjustable qa1 for the cobras, will those bolt up right? I looked at doing them few years ago but haven't pulled the trigger yet as they are kinda pricy, and I was unsure if they will bolt on.

XR7 Dave
09-01-2011, 03:08 PM
Not speaking from personal experience, but I've heard that people do use Cobra shocks on SC's.

David Neibert
09-01-2011, 03:19 PM
I had a very serious squating problem with mine. It was bad enough, that it showed in the rubber left from the rear tire, with it being narrower than it should be from camber changing during the squat. I added air bags to the rear springs, and with them set at 15 psi, the tires stay flat. I run QA1 coil overs in the front, and the rear camber set at "0". The air bags also allow you to tweak the suspension for level straight launches

I am thinking about putting a solid axle and mini tubing it over the Winter so I can go to some real rubber on it.

Bruce,

You really need to bring that car to the Shootout this year.

David

392Bird
09-01-2011, 08:36 PM
David, I wish it was closer. No trailer, and farther than I want to drive this looking for E85 stations. I drove it about 200 miles 1 way last month to Louisville, but since no E85 in route, had to bring (2) 5 gal cans with me. The car did great, but was as far as I want to drive it in one stretch. The side exhaust and YSi get a little old after a couple hours. I guess I am just getting old.

I will have it at NMRA in Bowling Green Ky, Sept 29 - Oct 2. It is only 80 miles, so a little easier on a 68 year old man. :)

seawalkersee
09-02-2011, 12:56 AM
The stock cobra shocks will bolt up. You may get a knocking noise from the rear if you do not add a spacer to the top. The difference in the diameter is like 10mm for the Bird and 8mm (just as a reference) for the Cobra. I have a pair on the rear of my white car and there is a noticable difference as the ones for the Cobra are stiffer. They are the FACTORY ones though, non-adjustable.

SWS

SCrazy
09-02-2011, 07:31 AM
Are your rear shocks factory style or are they aftermarkets? I have the factory cobra ones in the rear of my car. They are a good deal stiffer than the factory ones for the bird. Not sure if your car will overpower them or not.

SWS

All my shocks are the Koni adjustable shocks set to full firm.

STEVE29
09-02-2011, 07:45 PM
All my shocks are the Koni adjustable shocks set to full firm.

This may be a silly question, but which Koni's are you using? If they are single adjustable, they only adjust the rebound not the compression, which doesn't help you rear squatting.

Mike8675309
09-02-2011, 07:59 PM
This may be a silly question, but which Koni's are you using? If they are single adjustable, they only adjust the rebound not the compression, which doesn't help you rear squatting.

the only koni's that fit without some significant effort are the single adjustable.

STEVE29
09-02-2011, 08:11 PM
Well, I'm not familiar with the suspensions on the SC's but most Koni's shocks/struts that I've seen that are single adjustable only adjust rebound not compression. So setting them to full stiff in the rear won't help the rear from being pushed down and will only slow its rise back up. Might be better off going full soft in the rear for rebound.

EECDOC
09-03-2011, 09:22 AM
Been running them for several years. Car has 60 footed in the 1.4 range at 3 tracks.


http://i292.photobucket.com/albums/mm20/eecdoc/IMG_0652.jpg


http://i292.photobucket.com/albums/mm20/eecdoc/IMG_0081_1.jpg


http://i292.photobucket.com/albums/mm20/eecdoc/IMG_0659_1.jpg

rzimmerl
09-03-2011, 10:02 AM
Nice setup and pics, love the aluminum subframe mount bushings.

CMac89
09-03-2011, 01:22 PM
That's a nice setup. Unfortunately, the IRS forces you to run coil overs in the front and shocks in the back. That's backwards. Rear shocks are the most important shocks, in drag racing. The rear shocks will control how much the car squats.

EECDOC
09-03-2011, 02:39 PM
No argument with what you're saying. I've been toying with the thoughts of a live axle since 04. Just decided to see how quick I could get the MN12 IRS to 60'. The 1.44-1.48 I've managed to pull has made me smile.

Oh and actually the factory front is a coil over shock also. The custom ones I'm running just weigh a bunch less. They are from a custom run made back a good 5-6 years ago. I think Bruce had the original set made.

Mike....

XR7 Dave
09-03-2011, 10:00 PM
This is how it's done:

http://img71.imageshack.us/img71/4248/siskahardlaunchjc2.jpg

CurtisPaulfrey
09-04-2011, 12:19 AM
^ Solid axle?

VicRattlehead
09-04-2011, 12:42 AM
^ Solid axle?

No, still IRS. It's eecdoc's from above.

ScrapSC
09-05-2011, 11:00 PM
I have a picture of mine at launch. Im not sure if it is to much travel or not. But I have been able to get down to a 1.63 60ft... Stock suspension and I havent upgraded any of the bushings. Guess that is needed now....