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Advantages/ Disadvantages of IRS..

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Old 09-03-2011, 01:25 PM
  #11  
uberstang1
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Don't do it solider. Thats a ton of money you can do something better with.
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Old 09-03-2011, 02:28 PM
  #12  
Kerns
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Originally Posted by uberstang1
Don't do it solider. Thats a ton of money you can do something better with.

Pretty much. IRS will increase comfort and handling with the ride. It weighs more than a SRA and to properly setup an IRS to handle hard launches it takes a lot of money.
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Old 09-03-2011, 03:42 PM
  #13  
Harryman2002
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Yeah but if he's not going to be drag racing every weekend who cares if its not super strong. If its going to be driven mostly on the street then why not do the swap? Superior ride quality and handling.
I pretty much never drag race so what possible reason would i have to keep the SRA. That could be the same for soldier.
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Old 09-03-2011, 03:57 PM
  #14  
Kerns
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But why drop 800$+ in an IRS for a car that you are using as your weekend toy? If it was free to do the swap? sure why not. Its more of a cost vs reward situation for me. The reward is not even close to worth the cost. And for it to be properly setup so you can do both? You are looking at around 1400$ or so.
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Old 09-03-2011, 04:04 PM
  #15  
Harryman2002
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That's almost like saying why spend $2000 for a supercharger. Its to make the car more fun to drive. I know i have way more fun driving my car with the IRS just because it handles so well. For people who drag race all the time then yeah its a dumb swap but for street/auto-x ill take an IRS any day.
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Old 09-03-2011, 04:40 PM
  #16  
teej281
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Originally Posted by Kerns
Pretty much. IRS will increase comfort and handling with the ride. It weighs more than a SRA and to properly setup an IRS to handle hard launches it takes a lot of money.
Not only will it handle better because its a better design for it, but it will also handle and respond better because the car would then have something known as BALANCE! It adds weight, this is VERY true! But where does it add weight one would ask? Right where the car needs weight added. At the rear of the vehicle. Adding the weight to the back might make the car heavier, but it helps balance it out and put it closer to 50/50 distribution.

Originally Posted by Kerns
But why drop 800$+ in an IRS for a car that you are using as your weekend toy? If it was free to do the swap? sure why not. Its more of a cost vs reward situation for me. The reward is not even close to worth the cost. And for it to be properly setup so you can do both? You are looking at around 1400$ or so.
So me buying my IRS outright at $400 and not having to give my SRA in return is really $800? You find the right guy who realizes that both parties are benefiting from the swap equally, you find yourself an even trade or minimal cash to put in, and its totally worth it.

Even if it takes $400 cash and your SRA for the swap, bushing kit is right around $650 and if you wait, you can usually find a sale around christmas time or tax return season you can find good deals too. And if you do the install yourself(plenty of online write-ups and directions and advice can be found on Fulltiltboogieracing.com...which is the only source I would buy the bushings from anyways) youre looking at just over a grand for a properly setup IRS. Throw a cover in there and youre looking at $1200. Build an SRA properly with 31 spline axles and differential($500ish for 03 cobra diff and moser 31's), new shocks($200 for a good set of shocks), upper and lower control arms(another $300 for UPR or something) or a torque arm and phb setup($978 from MM) and you have about the same or a lot more wrapped up in building your SRA than you would doing bushings and a cover on the IRS. Might be a little stronger, but to me I couldnt justify spending that kind of money on a suspension design that was also used since 1979 either...and rides like it too.

Originally Posted by Harryman2002
That's almost like saying why spend $2000 for a supercharger. Its to make the car more fun to drive. I know i have way more fun driving my car with the IRS just because it handles so well. For people who drag race all the time then yeah its a dumb swap but for street/auto-x ill take an IRS any day.
This is an extreme example, but I do agree. Its hard to comprehend what the rear suspension of a stick axle car feels like in comparison to an IRS without driving it yourself. Going from stick axle to IRS, there was worlds more confidence in cornering because the suspension is not able to move side to side like it is with an SRA without a PHB. That alone made a difference. To have the car feel stable in a corner was awesome! Then add on the fact that it improved the ride of the car worlds it made it much more comfortable to ride in compared to the SRA. I much rather ride in the car now with the IRS than when I had the SRA with a lot softer springs and less valved shocks.

Both examples properly built, they might handle the same on smooth surfaces, but the second you throw in a bump or uneven surface, bye bye SRA. For launching, use of slicks reduces breakage over street tires or drag radials because sidewall helps absorb shock, allowing one to launch somewhat like an automatic that is a smooth engagement on the drivetrain.

For a street car, no other choice to me other than the IRS.
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Old 09-03-2011, 05:01 PM
  #17  
Kerns
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Very valid points Teej. Don't get me wrong. I think an IRS is great, but for me, its just not worth the cost difference. But that doesn't mean its not worth the cost for someone else to do it.
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Old 09-03-2011, 06:25 PM
  #18  
Bpohlman13
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There really is very little to no cost difference. I got mine for a straight up trade. Only thing is, I had to drive a cuple hundred miles to pick it up. If youre into drag racing and drag race on a regular basis, then solid axle all the way, but if you want a nice smooth ride irs all the way.
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Old 09-03-2011, 06:36 PM
  #19  
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The guy that tj posted about has a stock irs except for diff bushings and a brace iirc he told me one time but I have slept since then. So it doesn't take a lot of money to make it handle high rpm launches. Just dome bias ply tires. I my self will never get rid of my irs for an 8.8 sraand I do mostly street racing and drag racing.
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Old 09-03-2011, 09:37 PM
  #20  
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FWIW ill be throwing one in my car as soon as i can find one!!!

mostly street and open track days, with the occasional trip to LVD
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