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msmistyk
04-09-2010, 07:16 AM
So I've been kicking around putting an IRS in Misty to get a smoother ride. I'm a little concerned about wheel hop, but have been told there are ways to prevent. I'm looking for some different points of view as to pros and cons of a swap, sources to purchase, fair price, etc... Discuss! Thanks :)

DNeinstadt
04-09-2010, 07:23 AM
Lots of ways to prevent, wheel hop is caused by accelerating more than 50% so I'm not sure you need to worry! JK!

The swap is supposed to be straightforward, cost is usually around $800 for the IRS itself but can probably source it a little cheaper on SVTPerformance or maybe locally, and I think they ride a heck of a lot better over bumps and turns..

Grenade
04-09-2010, 08:23 AM
Wheel hop if driven hard sometimes. Not going to happen a lot with you. Everything Dan said is correct. I've done it. Fairly easy swap. I think you would like it. Then your Terminator (96 version) would be complete.

msmistyk
04-09-2010, 08:26 AM
I say I'm concerned cuz I've gotten hop on F8L...

No1Ford
04-09-2010, 08:44 AM
I say not, I've driven both cobra's (irs) and of course Mach 1 (soild) and to be honest I could hardly tell the difference! Seem like a waste of money; kinda like spending $1000 for 10hp gain. But do what ever make's you happy.:)

FORDSVTPARTS
04-09-2010, 10:10 AM
The best way to do it if you can arrange it is to just find someone that has an IRS car that wants a solid axle.

If you could manage to get the two cars side by side on hoists it'd be an easy one day swap.

Grenade
04-09-2010, 10:22 AM
The best way to do it if you can arange it is to just find someone that has an IRS car that wants a solid axle.

If you could manage to get the two cars side by side on hoists it'd be an easy one day swap.

Very true, that's what I did.

SnakeByte
04-09-2010, 10:57 AM
Lots of ways to prevent, wheel hop is caused by accelerating more than 50% so I'm not sure you need to worry! JK!

The swap is supposed to be straightforward, cost is usually around $800 for the IRS itself but can probably source it a little cheaper on SVTPerformance or maybe locally, and I think they ride a heck of a lot better over bumps and turns..


Hmmmm.....I've been think of going to a straight axel?......:spin2:

Doodler
04-09-2010, 11:27 AM
Yeah, this would be a very easy swap in the 96. I pulled the 8.8 out my foxbody and swapped in an IRS in a day. And that took some engineering.

SnakeByte
04-09-2010, 11:48 AM
Let me know if you get serious about a swap as we might be able to work something out?

FORDSVTPARTS
04-09-2010, 01:59 PM
Let me know if you get serious about a swap as we might be able to work something out?

Then you just need to find someone to help you with a few upgrade goodies for the old 28 spline 8.8, Hmmm :Haveabeer:

msmistyk
04-09-2010, 02:20 PM
Let me know if you get serious about a swap as we might be able to work something out?

Why do you want to go to a solid? (just curious) If/when I do go ahead, I'd like to try the IRS for a while before I give up my solid...

Also what about my pipes? I have Basanni X with Magnaflow cat back. I've been told that will not work with IRS. And how about the gears, will my 3.7.3 work in an IRS? Do I need it to? I like having the dramatic "pull" from a stop and don't want to loose that...? That = more $$. :think:

HELLFYR
04-09-2010, 02:24 PM
Why do you want to go to a solid? (just curious) If/when I do go ahead, I'd like to try the IRS for a while before I give up my solid...

Also what about my pipes? I have Basanni X with Magnaflow cat back. I've been told that will not work with IRS. And how about the gears, will my 3.7.3 work in an IRS? Do I need it to? I like having the dramatic "pull" from a stop and don't want to loose that...? That = more $$. :think:

The IRS half shafts will only take so much abuse... then they snap leaving you stranded wherever you be.

I've seen them snap at 500hp, I've seen cars with 800hp never snap them.

WHEEL HOP IS THE ENEMY.

Get some sticky tires on there, all the mods to eliminate the torsion of the pumpkin and carriers and you should be fine.

Here is the "PostBan" Red Pill from SVTPerformance. He goes into all the IRS mods to make it "bulletproof".
http://www.svtperformance.com/forums/suspension-modifications-211/231900-level-5-irs-red-pill.html

Rod

SnakeByte
04-09-2010, 02:55 PM
It would be hard to talk me into doing it this year at all really, because if I did it, I'd do it right, and after the new inputshaft/clutch/PP/Flywheel and other mods I'm working on, I'm already over budget. And next year it's big twin screw hitting 650+ on pump. So it's gonna be a while till I get to even think about a solid axel and all that goes with it. In anycase if I were you I'd just keep the solid, but in the end it really all depends how you want to use the car.

DNeinstadt
04-09-2010, 02:55 PM
Why do you want to go to a solid? (just curious) If/when I do go ahead, I'd like to try the IRS for a while before I give up my solid...

Also what about my pipes? I have Basanni X with Magnaflow cat back. I've been told that will not work with IRS. And how about the gears, will my 3.7.3 work in an IRS? Do I need it to? I like having the dramatic "pull" from a stop and don't want to loose that...? That = more $$. :think:

Exhaust will not transfer, the pipes run up and over the axle on a solid and under it on an IRS.

The 3.73 gears are actually IN the axle housing so you would get whatever is in the IRS which for 03 Cobra's are 3.55's. You would accelerate slower but have a lower RPM at speed.
Dan

msmistyk
04-09-2010, 02:55 PM
Thanks Rod, I'll need most of that translated, but great info/link! So just out of curiosity, if a smoother ride is my goal, are there other routes I can take and keep the solid?

SnakeByte
04-09-2010, 03:07 PM
http://www.svtperformance.com/forums/suspension-modifications-211/231900-level-5-irs-red-pill.html

Rod

Great Thread!

BlownSVT
04-09-2010, 03:11 PM
IMO keep the solid. I have had both and even with my huge clunky overbuilt 9" solid i can barely tell the difference rooling down the highway. It still goes around a clover leaf just like before and i never have to worry much about it breaking anything. The gain by going to the IRS is so minimal i wouldn't even bother.

msmistyk
04-09-2010, 05:02 PM
The 3.73 gears are actually IN the axle housing so you would get whatever is in the IRS which for 03 Cobra's are 3.55's. You would accelerate slower but have a lower RPM at speed. Dan

Yep, I get that, my question is will the 3.7.3 work IN the IRS or am I stuck with the 3.55s? Thx!

TF2v97SN
04-09-2010, 05:32 PM
your stuck with 3.55's unless you buy new 3.73's for it

DNeinstadt
04-09-2010, 08:52 PM
Technically you can swap the gears out, but you would be better off buying a brand new set for the IRS...

HELLFYR
04-09-2010, 10:16 PM
Thanks Rod, I'll need most of that translated, but great info/link! So just out of curiosity, if a smoother ride is my goal, are there other routes I can take and keep the solid?

The BIGGEST difference I noticed compared to my 96 snake was going around a clover leaf that has a bump in it. The solid rear will jump on the bump and if you're moving fast enough will kick out on you slightly. With the IRS it sucks up the bump and smooth sailing. I think the IRS rides smoother comparing the 04 Mach to the 04 cobra. Neither was "harsh" in my opinion. Compared to the 96 they both ride much better. Could be what you are missing is a better quality UCA/LCA ??? I've never replaced those though so someone else would have to speak as to the change in ride characteristics when upgrading the control arms in the rear.

Grenade
04-10-2010, 07:48 AM
The differance between the two gear ratios is not a big factor. less than 5%

DNeinstadt
04-10-2010, 10:17 PM
Erica: http://www.tcstangs.com/forum/showthread.php?t=100388

GMan
04-10-2010, 11:07 PM
There you go, swap even up. Isn't love great? No cost to anyone. :cool4:

msmistyk
04-11-2010, 06:18 AM
The differance between the two gear ratios is not a big factor. less than 5%

...so 447 HP x 5% = 22 HP... 4% is 18 HP... still not worth it? :kickbutt: It is to ME!!!

msmistyk
04-11-2010, 06:21 AM
Erica: http://www.tcstangs.com/forum/showthread.php?t=100388

Thanks for the info... not sure I want to take this route. Need to let it digest awhile. :headbang: What options do I have with keeping the solid and improving the ride? Like Hellfyr said, the ride itself isn't bad, its the bumps that are BRUTAL.

BlownSVT
04-11-2010, 09:48 AM
Thanks for the info... not sure I want to take this route. Need to let it digest awhile. :headbang: What options do I have with keeping the solid and improving the ride? Like Hellfyr said, the ride itself isn't bad, its the bumps that are BRUTAL.

you could look into a different set of shocks/springs maybe a "softer" set would absorb a bit more of the shock. I am just confused though because frankly i never really noticed the ride with the IRS to be hugely better than without it.

LadyCobra
04-11-2010, 10:11 AM
After owning the 96 we had and now being in the 04, the ride is really really really different. I used to hate long trips in the 96 because of the bumps, especially on the roads here in Minnesota after a "rough" winter. If you went fast enough, didn't notice the bumps but there's only so much time you can spend with the cruise on 100mph :)

BlownSVT
04-11-2010, 12:40 PM
After owning the 96 we had and now being in the 04, the ride is really really really different. I used to hate long trips in the 96 because of the bumps, especially on the roads here in Minnesota after a "rough" winter. If you went fast enough, didn't notice the bumps but there's only so much time you can spend with the cruise on 100mph :)

are they just more stiff than the newer cars? I can't see the solid vs IRS being the difference there as much as the set up itself.

DNeinstadt
04-11-2010, 03:01 PM
5% difference in gear ratios doesn't give you HP Erica, wasn't sure if you were just proving a point or not. :)

Dan

msmistyk
04-12-2010, 08:14 AM
5% difference in gear ratios doesn't give you HP Erica, wasn't sure if you were just proving a point or not. :)

Dan
:blah: my point kinda was I was asking for facts/options to consider and I'd make the decision based on what's important to me, rather than be told I'm not aggressive enough with my car to worry about X or Y...

Thanks everyone for your input, I'm not convinced IRS is the answer I'm looking for so I'm gonna keep looking. :ford:

DNeinstadt
04-12-2010, 08:45 AM
I know I was teasing you about the hitting the gas thing, but wasn't sure if you knew that gears didn't equate to HP. I think IRS has a nicer ride but you could try using softer shocks or control arm bushings (for the solid) to try to soften the ride a bit...

Dan

66gtk
04-12-2010, 10:09 AM
Erica,
Is your suspension all 100% stock? Not sure how the 96s are set up, but springs/shocks make a huge difference in ride comfort on early cars. Some people also put too large of an aftermarket sway bar and such that also affects ride comfort in the early cars thinking more is better. However, not always the case if you like your car to remain a street car.