Cobraracer46

Why do want to deal with turbo system head aches when you can esily bolt on a 450 RWHP blower kit?

The IRS will definatly improve the handling and ride. You can check out my IRS upgrade thread here http://www.sn95source.com/topic/5091-how-to-upgrade-the-mustang-cobra-irs-for-better-performance/ were I upraded the IRS with polyurethane bushings and other parts.

Over a year ago, finally performed a major upgrade and overhaul to the IRS in my 2001 Cobra to address a scary instability issue under hard acceleration. It turns out that after I fitted a set of 335/35/17 Micherlin PS2 tires on Fikse FM 10 wheels, I started to feel an extreme side to side back end movement under hard acceleration that would start at 85 MPH and steadily get worse.. I looked into going with all Polyurethane into the IRS. At the end of 2012 after a lot of thought, I decided to go with Poly for all of the IRS bushings to avoid any NVH issues and to save some money as well. Some people might say that poly "sucks" or that poly is "cheap" and "crappy." Don't believe it. Some numbers Pulled out of a discussion from a mustang site to show that Polyurethane is a perfectly acceptable bushing material for use in the Cobra IRS suspension. After upgrading the IRS in my car with poly, the handling has noticeably improved, without having to make painful sacrifices in NVH. from Here is what I did during the big IRS suspension overhaul: From Maximum Motorsprts: Complete IRS urethane differential mount kit with a removal tool for $56 that will transmit ZERO gear noise to the passenger compartment. IRS differential mounts, urethane, complete kit, 1999-04 Cobra [MMIRSB-45] : Maximum Motorsports, the Latemodel Mustang Performance Suspension Leader! A complete IRS urethane control arm bushing kit for $65 shipped that will preserve some level of ride quality over broken pavement. 1999-04 Mustang Cobra Prothane Irs Control Arm Bushing Set at LRS - Free Shipping! Urethane Subframe mounts for $49.95 Urethane IRS Subframe Bushing Kit, 1999-04 [MMIRSU-1] : Maximum Motorsports, the Latemodel Mustang Performance Suspension Leader! $16 for 14 MM sub frame bolts, Metric, not a "pretty-close" English-size. Use metric bolts for installation. 14mm hardware kit for IRS subframe & RLCA mounting, 1999-04 [MMF-4] : Maximum Motorsports, the Latemodel Mustang Performance Suspension Leader! A complete IRS tie rod kit for to replace the original ones that are shot and causing the wheels to wiggle back and fourth. IRS Adjustable Complete Tie Rod Conversion Kit, 1999-04 Cobra [MMIRSTR-3] : Maximum Motorsports, the Latemodel Mustang Performance Suspension Leader! I thought about this one long and hard and since I had the IRS totally apart, I stepped up and installed a $254 Ford racing diff cover as well with the money I save by not buying an IRS kit with Delrin and Aluminum bushings. 1999-04 Mustang Ford Racing 8.8" Irs Rear Differential Girdle, M-4033-G3 at LRS - Free Shipping!. I spent about $445 for IRS bushings and tie rod kit , plus another $250 for the Ford Racing Cover. Not too bad. A few pics of the install that I did my self in my home garage. drilling out the factory rubber subframe bushings and getting ready to use the Maximum Motorsports removal tool. Fully cleaned lower A arm bushing shell ready for a Prothane IRS poly bushing Cleaning out the bushing shells subframe bushing I ended using a the Maximimum IRS subframe bushing tool and a smaller disc from a Lise bearing race driver kit to remove the lower A arm factory rubber bushings along with a little heat from a propane torch. (no need to light the bushings on fire, just get the rubber warm.) I also made sure to Use plenty of anti size lube on the MM tool threads and not to use any power tools with the MM removal tool since the MM IRS subframe bushing removal tool had to survive and work double duty on the sub frame and lower control arm bushings. Many people by mistake have used an Impact gun with the MM removal tool, only to destroy the threads on the tool before all of the factory rubber sub frame bushings were removed. Compared to the lower control arm bushings, The factory rubber upper control arms easily come out with just a little bit of drilling, cutting and nothing else. Maximum Motorsports IRS poly rear diff mount installed. Maximum motorsports IRS toe links replacing the trashed stockers Fully upgraded IRS all cleaned up, filled with RED Line synthetic gear lube and ready to be reinstalled. ( 2003 Terminator cobra Half shaft and knuckle assemblies were left off to make the IRS easier to raise into position since I only had a floor jack to work with) Checking Bump steer with my home made gauge set up. After pulling my hair out, trying to get Zero toe change readings during the bumpsteer procedure, I called Maximum Motorsports and was advised that up to .040'' bump in compression and rebound was acceptable. The best reading I was able to get was around .008" Close enough. I made sure that the IRS only bumped in. One tip I picked up from another Cobra owner who upgraded a Cobra IRS with poly in the control arms was to mix the Supplied Prothane grease with a bit of Anti size and not to apply grease to the outside of the bushings. You only want the bushings to rotate around the bolts, not the shells so thats what I did. Properly greasing the poly IRS bushings during installation eliminates the need to occasionally lube them and it eliminates the need to weaken the control arms by drilling into them to install grease fittings. As for the subframe, I did apply a bit of grease to the outside of the Poly sub frame bushings and with just an aluminum floor jack, the IRS assembly popped back into the car really easy. Since I avoided installing Delrin or aluminum bushings on the IRS subframe there was no need at all to spread the torque boxes or deal with other head aches to reinstall the IRS subframe back in the car. I was expecting the ride to become a bit more harsh with poly replacing all of the rubber, but I'm in shock that I can't seem to notice any increased harshness. - - - Updated - - - will add that to use the the Maximum motorsports IRS subframe bushing removal tool to remove thefactory rubber IRS lower control arm bushings, you will need to a Lisle race bearing driver kit pictured below- - - Updated - - - It only took me a year, but the Cobra IRS Brembo brake conversion is done. Surprisingly, about the only performance difference I have noticed so far is that the parking brake works better than before.

If you have some deep pockets, you can go with a ECM meter. The engineers at Ford used two ECM Lambda pro A/F monitors on a SN95 V10 mustang that run over $3500 each! http://powertrain.net/product_pages/lambda_page.htm

Some more drag race K member carnage. A brand new drag race front A arm with a crack

335/35/17 Micherlin Pilot sport tires on 17X10.5 Fikse FM 10 rims

One of the Broken K members looks like an AJE. Not sure about the rest. The story is that the companies that built those K members went for light weight instead of strength and the result is parts that eventually fail.

I prefer the factory K member, but tI had to choose an aftermaket K member, the Maximum Motorsport would be my choice as the quality is top notch and its strong. Flimsy drag race K member top and the super strong MM unit on the bottom. scary pic. Flimsy drag race K member that looks about as strong as a fold up lawn chair and the super beefy factory K member

The light weight tubular K mambers scare the crap out of me. No way would I run a drag race K member on my heavy 3700 pound Cobra convertible. Tubular A arm broken

Exsessive RPM's and detonation will destroy the stock connecting rods, so its suggested to keep the rpm's on a stock motor with a V7 below 6K and avoid detonation at all costs in order for the stock short block to survive. Once you are ready to rebuild the short block and outpower any turbo set up with the outstanding V7 blower, I would recomend Manley's new "heavy beam" connecting rods that are specifically designed for supercharged motors. Check out the Manley heavy billit rod specs: 14518-8 Stock Length w/ 22mm pin 7/16 ARP 2000 bolts 5.933" length 2.239" 680 grams Heavier beam for forced induction applications Specs for the standard 4.6 Ford pro series rod is the same as above except for the weight (602) grams. I wonder how this new 680 gram rod compares with the 650 gram rod made from 300M tool steel? I would also suggest the Manley platinum series pistons with the upgraded tool steel pins.

Outstanding build!

For a mostly street driven mustang, I would focus on maintaining good and quiet ride. Coil overs and delrin bushings can be too noisy and harsh for some. The Eibach pro system plus (Spring, sway bar and shock) kit is hard to beat for a street mustang. I would also recomend 2003-2004 Cobra front control arms if you can still find them new.

Taken last year in Lake Tahoe, but the car is exactly the same today. LOL

It's an open ended question as to what performs better, blower or turbo, but superchargers can go head to head with turbos. Take a look at this: 29 pounds of boost out of a T-Trim Vortech results in a 7.99 170 MPH.

It seems that turbo kits are nothing but head aches. In my view, if you want add bost to your Mustang, Supercharging is the way to go as everything is engineered to bolt on and fit correctly. Plus swapping out the factory k member is not required.