IRS vs SRA
06-02-2010, 09:48 PM
#11
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Join Date: Oct 2006
Location: Texas
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Thanks guys.
Also, I would love for anyone with an IRS swap to list all the parts they NEEDED to swap over to make it work. that way we can take care of the issues of not knowing what needs to be swapped for different trannies and years. I will post it in the original post with a credit to you.
Also, I would love for anyone with an IRS swap to list all the parts they NEEDED to swap over to make it work. that way we can take care of the issues of not knowing what needs to be swapped for different trannies and years. I will post it in the original post with a credit to you.
06-03-2010, 01:40 AM
#12
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Added '99 Cobra/ '01 Early GT transfer list.
And 94, to adress your comment, I guess I should have said it different. What I mean is, the Cobra owner is planning on pushing a ton of power(most likely a whipple/KB swap), so they are looking for a stronger, cheaper rear to build. Most GT owners are looking to do the swap for autox/open track or comfort. So I dont think most ppl do the IRS swap then mod the IRS more than maybe the bushings and a brace.
And 94, to adress your comment, I guess I should have said it different. What I mean is, the Cobra owner is planning on pushing a ton of power(most likely a whipple/KB swap), so they are looking for a stronger, cheaper rear to build. Most GT owners are looking to do the swap for autox/open track or comfort. So I dont think most ppl do the IRS swap then mod the IRS more than maybe the bushings and a brace.
The bushings kit, bumpsteer kit, end links and tie rods cost almost the same if not a little less than the LCA/PHB(or WL)/TA setup.
The costs for building both are moot, the more comfortable, more capable of putting both tires on the ground while going around an uneven surfaced corner is imho the better rear.
I will also say that the IRS is a POS IRS compared to others, the Ford engineers were force to engineer it into a chassis that was not built/had no intentions of an IRS. Not only that, there are a few articles floating around where the engineers complain about the marketing department forcing them to use rubber bushings that everyone complains about due to NVH concerns.
Get what you wanna work with, I chose to ditch the SRA/TA/LCA/PHB setup due to ride quality issues (I have a pretty bad back due to being sideswiped by a semi years ago). The IRS is just better in every facet in my eyes due to the ride quality and it's ability to keep both tires planted on uneven surfaces, others may disagree. =P
from hoss's other thread,
I recommend IRS swaps for pretty much anyone except for those looking to drag their cars. The stock IRS is by no means great tho, and cost to build wise is about the same as a properly setup SRA. The ride with the SRA, PHB, TA, LCA, & CO setup is considerably harsher than with the IRS, full polyurethane bushings, CO, EL, & TR/BS is much much more comfortable and handles much better than the fully built SRA on the road.
I've loved every minute of driving the car with the IRS in it. After finishing the MM max grip kit with the IRS I feel like the car is very neutral with a tad bit understeer at higher speed turns due to the staggered setup I currently have.
The IRS is believed to be more expensive to build due to the belief that LCA/UCA's and the SRA is ready to attack the road course. There is also a belief the level 5 halfshafts are required, I have read enough threads on people breaking level 5 halfshafts to believe that they are beefier but not necessarily necessary. I've launched the car a few times and have had very minimal wheel hop (launches were stepped up from 1k-1.5k-2k-2.5k-3k drops)
IMHO, DO IT!
And Hoss, I hate you and your 3 hour install.. with the exhaust problems and the problems with the bushings it took me a total of 16 long *** hours=/
I've loved every minute of driving the car with the IRS in it. After finishing the MM max grip kit with the IRS I feel like the car is very neutral with a tad bit understeer at higher speed turns due to the staggered setup I currently have.
The IRS is believed to be more expensive to build due to the belief that LCA/UCA's and the SRA is ready to attack the road course. There is also a belief the level 5 halfshafts are required, I have read enough threads on people breaking level 5 halfshafts to believe that they are beefier but not necessarily necessary. I've launched the car a few times and have had very minimal wheel hop (launches were stepped up from 1k-1.5k-2k-2.5k-3k drops)
IMHO, DO IT!
And Hoss, I hate you and your 3 hour install.. with the exhaust problems and the problems with the bushings it took me a total of 16 long *** hours=/
06-03-2010, 02:08 AM
#14
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Join Date: Oct 2006
Location: Texas
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Re-Edited. Hopefully it is easier to read and find stuff. I also added some link for further more indepth info. I will continue to add and re edit. If someone finds a mistake with a FACTUAL part of my article, please let me know. I will edit it. Post any links and information that can give a positive contribution to this thread.
We can make this the meca of IRS and SRA info
We can make this the meca of IRS and SRA info
06-03-2010, 08:37 AM
#16
Some things to add to the list of parts needed is if you have any kind of wide wheels out back you need the low-profile IRS bolts from Maximum Motorsports and you will need to check the subframe mounting bolts i think it is to make sure they are 14mm, and if they arent, you need to get those as well.
Also duely noted...buchings are a B!TCH to do!!! They take forever but are majorly worth it, but dont go with urethane, go with Delrin if you fully want to get rid of wheel hop and want a freely moving IRS. And you NEED to go with the tie-rod ends as well to complete the package.
Moreover, for any kind of driving, if you would go with an IRS you will need to do either a new rear end girdle(differential cover) or a differential brace to combat all the flexing and stuff that the differential deals with. If you dont, you may just get a cracked differential cover and that would be bad...
Another thing to note is that there are aftermarket control arms that are made for the IRS if one is really into making the IRS a badass machine, but they only accept coilovers, but the coilovers are another thing that can be added to make the IRS one bad piece.
One thing though that would justify getting an IRS alone...THAT FRIGGIN EXHAUST IS SEXY AS HELL!!!!!!!! I love the way IRS exhaust looks.
That is all...
for now.
Also duely noted...buchings are a B!TCH to do!!! They take forever but are majorly worth it, but dont go with urethane, go with Delrin if you fully want to get rid of wheel hop and want a freely moving IRS. And you NEED to go with the tie-rod ends as well to complete the package.
Moreover, for any kind of driving, if you would go with an IRS you will need to do either a new rear end girdle(differential cover) or a differential brace to combat all the flexing and stuff that the differential deals with. If you dont, you may just get a cracked differential cover and that would be bad...
Another thing to note is that there are aftermarket control arms that are made for the IRS if one is really into making the IRS a badass machine, but they only accept coilovers, but the coilovers are another thing that can be added to make the IRS one bad piece.
One thing though that would justify getting an IRS alone...THAT FRIGGIN EXHAUST IS SEXY AS HELL!!!!!!!! I love the way IRS exhaust looks.
That is all...
for now.
06-03-2010, 09:53 AM
#17
Great write up but there are a few things I want to add
It is not the Trans that would make you need to swap the drive shaft it is the Pinion Bracket this is the round thing on the front of the differential that the DS bolts to with 4 12mm 12pt bolts. On the Cobra the bolt pattern is a little more spread out.
So you can either swap DS or swap the Pinion bracket from the SRA onto the IRS. Is this true for all years not sure it was true for a 04 IRS into a 96 GT.
And if you do not swap rear brake lines you might have to bend them a little but be careful you can kink the brake lines and your rear brakes will not work properly. Again this was for a swap on a 96 not sure of the interference issues on other years.
I had to remove the Pinion Snubber also to get the IRS into my car
It is not the Trans that would make you need to swap the drive shaft it is the Pinion Bracket this is the round thing on the front of the differential that the DS bolts to with 4 12mm 12pt bolts. On the Cobra the bolt pattern is a little more spread out.
So you can either swap DS or swap the Pinion bracket from the SRA onto the IRS. Is this true for all years not sure it was true for a 04 IRS into a 96 GT.
And if you do not swap rear brake lines you might have to bend them a little but be careful you can kink the brake lines and your rear brakes will not work properly. Again this was for a swap on a 96 not sure of the interference issues on other years.
I had to remove the Pinion Snubber also to get the IRS into my car
06-03-2010, 10:05 AM
#19
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Join Date: Oct 2006
Location: Texas
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Great write up but there are a few things I want to add
It is not the Trans that would make you need to swap the drive shaft it is the Pinion Bracket this is the round thing on the front of the differential that the DS bolts to with 4 12mm 12pt bolts. On the Cobra the bolt pattern is a little more spread out.
So you can either swap DS or swap the Pinion bracket from the SRA onto the IRS. Is this true for all years not sure it was true for a 04 IRS into a 96 GT.
And if you do not swap rear brake lines you might have to bend them a little but be careful you can kink the brake lines and your rear brakes will not work properly. Again this was for a swap on a 96 not sure of the interference issues on other years.
I had to remove the Pinion Snubber also to get the IRS into my car
It is not the Trans that would make you need to swap the drive shaft it is the Pinion Bracket this is the round thing on the front of the differential that the DS bolts to with 4 12mm 12pt bolts. On the Cobra the bolt pattern is a little more spread out.
So you can either swap DS or swap the Pinion bracket from the SRA onto the IRS. Is this true for all years not sure it was true for a 04 IRS into a 96 GT.
And if you do not swap rear brake lines you might have to bend them a little but be careful you can kink the brake lines and your rear brakes will not work properly. Again this was for a swap on a 96 not sure of the interference issues on other years.
I had to remove the Pinion Snubber also to get the IRS into my car
Also, the transmission does have a little to do with the swap issue. The t56 has a different length than the t3650 and t45, so that comes into play as well. But i will make sure that is clear in the article.Thanks man.
TJ Added your stuff to!
EDIT: Added in IRS toque specs
Last edited by H0SS302; 06-03-2010 at 10:26 AM.
06-03-2010, 03:08 PM
#20
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Join Date: May 2007
Location: Columbia, MO
Posts: 6,347
also...not sure the differential brace is a requirement. maybe more of a recommendation IMO. i've romped on my car and i don't have a brace. as long as you instantly get out of it if/when wheel hop starts to occur you should be fine.
i wouldn't imagine GT owners with 100 less hp having serious issues.