Solid vs. IRS.. who's running what?

[caliboy08]

my 96' cobra had the 03-04 IRS installed before i bought it. ive driven other solid axle cobras and i think mine rides just so much smoother, granted, it has bilstein shocks and eibach springs. i really wont be taking it to the strip, but i want to try my hand at road racing a little bit.

 

[racebronco2]

i had a 03 gt and now i have an 04 cobra ... the cobra rides better then the gt ... i now have the h&r race springs and now it rides about the same as the gt but handles alot better ... i replaced the traction lok with a trosen tr2 and i have no wheel hop dry or wet ... the irs and solid axle are equal if the track is smooth .... irs shines on irregular surfaces .... taking weight off the rear makes the weght distrubution even worse then it is already .... that would be fine for the strip but on the street it would plow really bad just in case you do like to go fast around the turns

 

[silvercoffin]

Postban

Hey Postban

I like your page..the one your link goes to from here. Very informative. Thanks

I noticed that you say level two or five half shafts. I am trying to figure out why JDM keeps telling me that all I need is level two. I explained to them that the next thing I am having done after the IRS build up is a Whipple.

I'll have to ask the shop about all the bushings you mention. I dont know if they were just going to change them or not. The shop is recommending level 2s, a pinion snubber and IRS Brace to me. They didnt mention different bushings, but maybe they just do that.

So why level two?

and

Are the bushings necessary for strength or just ride/street driving comfort?

 

[lachj1]

I put a solid in last year with all Maximum motorsport stuff. I used their torque arm, panhard bar setup with the ride height adjustable lower control arms. You actually shave off I beleive another 25 lbs by getting rid of the quad shocks and upper control arms. you also dont need the differential damper and the Irs brackets in the wheel wells, those things are like 4-5 lbs each. It sends a little more road noise but it handles really well. There's an auto cross setup every 3 weeks in Bristol, ct. I'm going to try it out.

 

[Mrcobraguy]

I'm currently building my solid rear and its should be done in a couple of weeks. I can't wait to see what its going to be like.

 

[adamb258]

im torn, this sucks

 

[03 DSG Snake]

solids suck! My I.R.S. will be complete on monday ( I hope)

What are you putting into it?

 

[silvercoffin]

info

I ended up going with a beefed up IRS..

I didn't get any of the bushings everyone talks about here. I dont think they are necessary now..

I got the pinion snubber, IRS Brace and went with level two half shafts. When the shop took apart of leaking rear diff they found pieces of gear in the bottom. Instead of just replacing the messed up gear, I had an Eaton Posi installed.

Took it to the track in 90 degree heat and ran my best 60 ft since 470 rear wheel hp.. 1.73 60 and a new best 330ft too.. UNfortunetely on that run it was brackets and I hit the brakes resulting in an 11.91 @ 98mph...

BUT with a stock rear end, I only ran a 1.82 60ft when the car went 11.68 in the cooler weather!

I'm psyched because that was only my third run with this set up and each run was 2 hours or more apart, Sunday at etown sucks...but i couldnt wait.. Hopefully the rain will hold off friday and I will be able to get some serious practice in. I know I can definetely do better than a 1.73 now..

So I now have.............

Mickey Thompson Drag Radials 275 40 17 (with 15lbs air)
QA1 rear adjustable shocks (had them set on #8 sunday)
Eaton Posi rear diff still with 3:55s
Pinion Snubber
IRS Brace
Level Two Axles

Nothing else...no special bushings or anything..
Definetely have 11.5s if not better coming in the cool weather... cant wait

 

[Fuerza]

SilverCoffin, what are the part number on those QA1 adjustable shocks?

 

[silvercoffin]

hmm

Dont know the part number. I had JDM put them on for me when I was in for some other work. I am sure you can get them cheaper elsewhere..but sorry i cant help you with that... I see advertisments in MMFF Magazine all the time for QA1 you can probably just doa search and contact the company directly.

 

[Fuerza]

Dont know the part number. I had JDM put them on for me when I was in for some other work. I am sure you can get them cheaper elsewhere..but sorry i cant help you with that... I see advertisments in MMFF Magazine all the time for QA1 you can probably just doa search and contact the company directly.

What springs are you using with those shocks?

 

[silvercoffin]

...

Stock springs. Is there something better out there now?

I didnt do as well last night. Best 60ft was only a 1.78 and then 1.83 1.82 1.83 and 1.81

Oh i left out my first run...which I had the same set up as sunday when I ran a 1.73 60... same shock setting.... I spun so bad it was rediculous....but nice not to hop...

I have come to the conclusion that Englishtown definetely does better track prep on sundays, plus Im sure it doesnt help having all the imports F up the track on fridays...but I was one of the first cars out...so i dont think they did much to the track...

anyway with my 1.78 all i ran was a 11.95

PIsses me off because you go to practice on fridays when you can get runs in and the track is totally different...really sucked..

 

[BLWN03]

I'm swapping out my IRS with a 01 Bullitt...setup for setup..i like to dump it @ 6k at the track and need a hop-less rear for the colder months...i wasn't going to do it but decided to finally bite the bullett after riding in Juiced46's car..i swear there is really not that big of a difference in ride quality.

700+ hp is in my future as well so i need something that can handle it with ease.

 

[Fuerza]

Silvercoffin, what is that Pinion snubber??

 

[Akuma]

I put a solid in last year with all Maximum motorsport stuff. I used their torque arm,

Torque arms are worthless. Dodge tryed to make them work for years. Other than that you have a nice setup going. I have a similar setup other than i have a currie 9inch.

I started off with doing the DSS level 5 halfshafts but i couldnt keep dustboots on them. So i went to GKN halfshafts ( made the halfshafts for the 96-98 cobras and the 96-00 vipers). The GNK's worked great until i burnt up cylinders 7&8 (should have done the head cooling mod). And now I'm going with a 96 block, stroked and bored to 5.4 (Vt). With that engine and Twin turbos there is no way my IRS would hold up to that much power, hence the 9inch.

Now that i look back on it i should have done it right the first time and went with the solid.

 

[NotoriousGT350]

Subscribing

Gotta subscribe to this.
I should be getting my Cobra shipped here soon( :cuss: if they can find an enclosed trailer). I've been researching over the past few weaks into beefing up the suspension such as half shafts, IRS bracing, bushings, shocks, subframe connectors. Once I get the cobra, I'm hoping it might dyno at least 450rwhp. So I'm also looking into getting a LFP H/E, and the LFP CF DFX package. With it only having 2,827 miles, I'd rather upgrade the drivetrain, suspension, and cooling before I go into putting more power.

I thought about the solid swap, but I think a beefed up IRS will be alright for what I have. It's goingto be my street cruiser with occassional trips to the drag.

 

[silvercoffin]

ok my update

I went with the following

Level 2 shafts
snubber
IRS Brace (already started leaking again what the hell?)



WIth Bassani X, Cat back, CAI, CHip, Pulley, on BFG drag radials I ran a previous best of ......

11.68 @121mph with a 1.82 60ft (on a 43 degree day with a cold car)



WIth the addition of the shafts,snubber and IRS Brace and MIckey Thompson Drag radials I ran..........

11.58 @ 120mph with a 1.70 60ft (on a 75 degree day cool car)

Also ran a 1.69 60 on another run.....and I know I can do better

 

[silvercoffin]

Irs Brace

I had my rear diff resealed and the IRS Brace added. After two trips to teh track it already started leaking. ANyone ever had that happen?

The shop said that my cover must be warped or cracked and that there was no way they could tell. The claim to have test drove it and checked it for leaks. Opinions?

I am really mad that Ill be paying for it to be fixed again. Not going to mention the shop until I see how the take care of me.

 

[Screamin Cobra]

IRS for the 04

 

[Tide612]

I am thinking of going to an IRS again. This one is going to be beafed up. I want a list of every possible thing you can do to the IRS and it not break. Or so call not break. Please post up.