This is topic Maximum Motorsports vs IRS for foxboy in forum Road Racing, Auto X & Drifting at Northern California Ford Owners  .


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Posted by 6D9 (Member # 7001) on :
 
Down the road i would like to set the Foxbody up for handling and was looking at both set ups. I know the IRS will ride better on the street but what about track performance? What works better? Does the MM set up ride like a dump truck on the street?
 
Posted by Blind (Member # 3052) on :
 
do you mean the MM t/a + phb? It rides fine on the street.

IRS on the track is better on tracks that are bumpy or have quick transitions.

Read the MM shop car swap to IRS article to find out some more, but in short their shop car went from the full MM package to an IRS with their delrin bushings setup and gained a couple seconds per lap in a back to back test.

http://www.maximummotorsports.com/store/index.php?main_page=tech_rear_susp_irs_faq_royce
 
Posted by 6D9 (Member # 7001) on :
 
Yes the ta+pb. Thanks for the article!
 
Posted by phildog (Member # 1214) on :
 
A stock IRS will get killed by a SRA with a TA and PHB . You would need to upgrade the IRS significantly to duplicate the performance of a MM kitted SRA.
 
Posted by SF Coupe (Member # 1810) on :
 
I was at Buttonwillow last month. Maximum Motorsports was there with their foxbody shop car which is the car mentioned in the article. They brought along Mike Croutch who used to be their driver in AI. It was his first time driving the car with the IRS. He said he preferred the TA/PHB. Main reason, the TA/PHB puts the power down sooner and much better than the IRS.
 
Posted by SydeWaySix (Member # 3596) on :
 
quote:
Originally posted by SF Coupe:
I was at Buttonwillow last month. Maximum Motorsports was there with their foxbody shop car which is the car mentioned in the article. They brought along Mike Croutch who used to be their driver in AI. It was his first time driving the car with the IRS. He said he preferred the TA/PHB. Main reason, the TA/PHB puts the power down sooner and much better than the IRS.
MM PHB/TA FTW [burnout]
 
Posted by 6D9 (Member # 7001) on :
 
Looks like I will be keeping the SRA!
 
Posted by Blind (Member # 3052) on :
 
quote:
Originally posted by phildog:
A stock IRS will get killed by a SRA with a TA and PHB . You would need to upgrade the IRS significantly to duplicate the performance of a MM kitted SRA.
I don't know, I wouldn't really call putting coil-overs, replacing the bushings, and replacing the tie-rods a significant upgrade.

compared to a stock SRA, there's no comparison the IRS is hands down a better starting point.

SRA -
~$1200-$1400 for the TA, PHB & lower control arms depending if you're getting standard or heavy duty, non-adjustable or adjustable lca's
~$800-$1100 for MM race bilsteins or Koni DA's all around
$140 for torque arm rear springs (not doing coil-overs)
$450 for coil over kit with springs
$370 for MM adjustable roll bar


IRS -
$1100 for the race grip package.
(This Grip Box includes:
Aluminum Differential Bushings - MMIRSB-40.1
Delrin Upper Control Arm Bushings - MMIRSB-2
Delrin Lower Control Arm Bushings - MMIRSB-1
Urethane Subframe Bushings - MMIRSU-1
IRS Adjustable Complete Tie-Rod Kit - MMIRSTR-2
Adjustable Rear Swaybar Endlinks - MMRSB-94
Low Profile Subframe Bolts, rear mounts - MMF-1
14MM Subframe Hardware, front mounts - MMF-4
Specialty tools and detailed instructions to make the job a breeze)
$435 for coil-over kit with springs


These are just MM prices, I used the kits when they were cheaper. There are cheaper kits elsewhere, sure. Like the fulltiltboogie.com IRS kits that are $700 and not $1100 that most people say are even better than MM. You could go Griggs, KB, or whoever for the SRA stuff as well, this was just an A vs B comparison or a similarly setup adjustable rear end (ride height, corner balance, bump steer, and swaybar where applicable).


I have one car of each, they both have their pros and cons. I prefer the IRS personally.
 
Posted by sneakyfox90 (Member # 9379) on :
 
A built sra will KILL a stock IRS in the corners

And ur pice for the IRS didn't include any shocks?
But u added the price off four shocks to the sra set up lol

And u don't necesarily need the koni da or mm race bilstiens for the sra...

But out of the two I think I can agree there's a bit more potential to be seen out of the IRS

[ May 07, 2012, 04:46 PM: Message edited by: sneakyfox90 ]
 
Posted by Blind (Member # 3052) on :
 
quote:
Originally posted by sneakyfox90:
A built sra will kill a stock IRS
And ur pice for the IRS didn't include any shocks?
But u added the price off four shocks to the sra set up lol

And u don't necesarily need the koni da or mm race bilstiens for the sra...

But out of the two I think I can agree there's a bit more potential out of the IRS
yes, the IRS has bilsteins already so they only need a c/o kit. Atleast the 2003 IRS I bought did, and it cost me $150 to find a set of front 03 cobra bilstein struts to match. I'm not sure if all the 99-04 IRS units came with bilsteins or not.

I was just doing the prices for comparison to a similar level, you can cut the shock/strut prices by a bit on the SRA but it's cheaper to buy the set of 4 than to buy rear/front pairs. There's no way anybody is going to throw a TA/PHB kit onto a SRA and use the stock shocks!
 
Posted by phildog (Member # 1214) on :
 
I thought the OP's original question was stock IRS v. TA/PHB SRA. To which I would choose the modded SRA. But, after driving an IRS Fox with the full MM kit on it, I would go with a built IRS over a SRA setup. Ride quality and NVH is ten times better with the MM IRS than the last Griggs SRA car that I drove.

But the bottom line is that there is no bottom line. There will always be pros and cons for each.
 
Posted by 6D9 (Member # 7001) on :
 
Great information guys thank you very much! Right now the car just has Sportline springs and Tokico blues. It seems to handle great for the cheap budget stuff.
 




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