Is this possible? IRS swap

[MarcVIII]

Is this possible? V6 to Cobra using Mark VIII parts

I currently own a 93 Lincoln Mark VIII. It has the all aluminum 32v DOHC 4.6L just like the Cobra engine. The Mark VII is like a prettier T-bird. Its a great car, except for the weak tranny (damn AODE).

I wanna get a 99-04 v6 Mustang Convertible (lower insurace, gonna pull ****load of parts off anyways) and put this engine in. I know I'll need a computer, supercharger (as mine is an N/A engine) and other supporting things. I guess I'm looking for a Yellow 99 Anniversary Edition V6 Convertible. Miles don't matter as I plan on upgrading all the components that wear (brakes, suspension, engine, trans). Just looking for a perfect body car with no mechanical problems and nice paint. A Mach 460 sound system would be nice too. And Leather. I don't care if it has a spoiler because I want a Cobra R spoiler. Also premium 16s don't mean that much to me, I'll probably put slicks on 'em anyways.

I plan on lowering the car with coilovers, stiffening the chassis with swaybars and tower braces, putting on big calipers w/ nice slotted rotors and semi-racing pads, 17" (maybe 18") rims (definately chrome, maybe Cobra Rs), and maybe a body kit. I want the car to handle the best it possible can so I wanted to steal the IRS from the Mark VIII (all aluminum) with an 8.8" center. While I was at it might as well steal the 1 piece aluminum driveshaft, get it re-balanced and cut to fit the stang. I want this car to have minimal body lean around the corners and be able to take turns. This is an aluminum IRS system (I don't believe the Cobras had that?) that I thought would do the trick.

A few generic Mustang questions:
1. What are the differences between a Cobra and the Base besides the engine, brakes, body molding, and trans?
2. Does the V6 have a different radiator, power steering (and rack and pinion), brake cylinder, or any other similar accesories than the Cobra?
3. Is it wiser to get a supercharger that came stock on the Cobras or aftermarket? If I go aftermarket wil the factory (Cobra) computer work or will I need an FMU and/or standalone? I'm not really knowledgeable on superchargers, but I assume they are kinda like turbos where you can get "bigger" and better. What's the max psi a stock SC can go?
4. Is there anything I can do to lighten up the car without spending out the ass on Cf or fiberglass fenders, hood, trunk lid, etc.? I know how to take out a spare tire, thanks for that one in advance. I want to keep rattles and stuff out too so I'm not pulling out sound deadener.
5. Does the 35th anniversary have anything special on the base car besides a badge? Are all 99s anniversary editions? Is there any merit to spending more on a car that is an anniversary edition? Do they come in yellow?
6. Has there been any advancements between 99-01 (newer is still too expensive for me if I'm gonna do all these mods) that would make me want the 01 or 02 (ok I lied a little maybe an 02)?
7. What options did the base car have besides sound system, rims, and spoiler? What does the Pony Pack include? Is that just for the outside lower ground effect stripe and a pony on the seat? Can a base get a Pony Pack?

Mark VIII parts to Cobra Conversion questions:
8. Will the IRS bolt up directly? Will the half shafts need to be shortened to clear the wheelwells? If I get wheel flares can they be installed without messing up the factory paint? I want them molded in properly.
9. Whats the "best" gearing for the rear end for both the auto and 6 speed trannys? I'm going to replace all the internals anyways, just want opinions. This is going to be a Street/Strip car.
10. If the rear disc caliper set up on the Mark VIII IRS is bigger (but still smaller than the fronts) than the v6 stock rear calipers will I need a proportioning valve to utilize them?

If you guys see any other red flags or oddities that I didn't think about, feel free to post. Please give me your opinions and solid answers to the technical questions. Any comments or criticisms are greatly appreciated.

 

[Black_Cobra]

B4 getting into any detail, are you sure you'll be ok with state vehicle inspection? You may have a problem when the reg says 6cyl and they pop the hood and find a fire breathing, supercharged V8.

 

[03-s281]

That would cost a **** load of money to do. Just buy a used 96 to 98 cobra
and throw a vortech on it. You can get a nice cobra for about 10k and supercharger for 3k. I owned a 93 markviii and the motor is a 4v but it has a different crank, intake and cam. Buy a used cobra and quit dreaming.

 

[Black_Cobra]

Here's a cheaper dream for ya. Get a 94-95 5.0 and drop a 5.8L crate engine in there. Make your own Cobra R with radio, AC, and so forth

 

[MarcVIII]

I had a 88 GT convertible, automatic. Rode like ****, slow response from the engine. It was mostly stock except air filter and chambered exhaust with H-pipe. It was slightly faster than my MAF and intake modded Mark VIII, wich I ran a 15.3 sec 1/4 in. I'd guess 14.9 tops. Sold it for my Twinturbo Stealth. The stealth is a better all around car, but its newer and was a stick. Now I want a new Mustang again.

I like the 99 bodystyle and I like the 4.6L DOHC engine. I want a good handling, great looking CONVERTIBLE. I know you can make insane hp with the 302, but I like the all aluminum, DOHC high / quick revving capabilities. I already have several of the expensive parts. I like working on cars and modifying. I have a lift, the tools, and the desire. We'll see on talent. You may call me a dreamer, but I was just trying to do something different with parts I already have to make a Cobra but better, faster, and lighter. Not to mention built the way I want with the parts I want. I plan on going to the drag stip as well as some sort of road course racing.

The Mark has a cast crank instead of a forged, and a different intake manifold. They are not completely hand built like the Cobras. I do research and I have owned this car for a long time. I know a decent amount about cars, a lot about American cars from 60s - up.

The Teksid block can handle 1500 hp. I wanted to get nice, light, newe internal components. I'm assuming the cams are different then the SC version too. I know I'm lacking in SC knowledge, but I'm willing to learn. Please don't flame me for laying out an idea that I'll try my damnedest to ACTUALLY do.

 

[Mustang5L5]

I like the 99 bodystyle and I like the 4.6L DOHC engine. I want a good handling, great looking CONVERTIBLE. I know you can make insane hp with the 302, but I like the all aluminum, DOHC high / quick revving capabilities. I already have several of the expensive parts. I like working on cars and modifying. I have a lift, the tools, and the desire. We'll see on talent. You may call me a dreamer, but I was just trying to do something different with parts I already have to make a Cobra but better, faster, and lighter. Not to mention built the way I want with the parts I want. I plan on going to the drag stip as well as some sort of road course racing.

What you want to do is gonna take a lot of work

I owned an '93 Mark VIII for a while, so i am very familair with the FN-12 chassis and even contemplated swapping the driveline over to my '88 Fox once the air suspension in my '93 began to go south. But after looking into it, and even though i am familiar with both chassis, i just didn't think it was worth it. My Mark 8 was fast too. I ran a 14.9 @ 94MPH with it stock.

SO i sold the Mark VIII and made myself famous in the process (click on my title under my username to see how)

SO to answer your questions:

NO, the Mark VIII IRS will not work at all. The Mustang IRS is a copy of it, but the mounting points are not similar at all. Even if you could bolt the IRS on, you'd need to swap out the halfshafts and rear braking system with a 99+ Cobra simply because the bolt pattern and offset is not the same.

As for the engine swap, well it's possible, but modular technology has come a long way since the good old '93 Mark 8. As quick as my Mark 8 was, the '03 GT with it's SOHC 4.6L pulls just as hard as the DOHC up top and is about a second quicker in the 1/4mile. It's a 260HP 302 TQ SOHC vs the 280/290HP and 285TQ DOHC of the Mark. Obviously weight and transmission play a big factor here, but the Mark VIII is not a Cobra motor. It can be modified into one though with an intake swap and maybe getting hotter cams. Unless you are gonna make 400+HP, stay with a 5-spd. The T-56 takes a good deal of HP to make usable.

What i am trying to say is instead of starting with a V6 and swapping your Mark engine into it, just get a GT and go from there. The SOHC motor is not that bad. Toss a blower on it and instant 12's or even 11's. Or even if you don't want to go that route, you can tinker with bolt ons and still get respectable performance. 99-01 GT's aren't that expensive nowadays anyway. Instead of spending time, and money putting a used Mark VIII engine in there you could be driving the GT and tossing on some bolt ons and making it faster and enjoying the car.

I love the Mark VIII and the DOHC too, but when i sold mine and bought my GT, i had NO regrets about not doing a swap of my own.

 

[MarcVIII]

Can the body be modded to take the Mark IRS? Its aluminum, which even the Cobra was not. The Mark can use Cobra R rims so how much different is the halfshafts and rear braking system with a 99+ Cobra simply because the bolt pattern and offset is not the same.

I want this car to turn amazingly and I don't want an SOHC engine. My DOHC is the lighter aluminum block w/ aluminum heads. THE lightest possible. My Mark engine is exactly the same as a Cobra minus intake, crank, and maybe cams. I plan on rebuilding the engine to more than a stock Cobra anyways- maybe 550 hp SC, 800hp with nitrous. I think dropping the compression and then making sick boost would do the trick. Or slightly higher compression with strengthened internals and slightly higher boost, but that puts more wear on parts, no? The engine fits and will run sick hard.

 

[Silver2003Cobra]

just buy a 99+ Cobra and call it good.. it already has everything that your thinking about doing, from the factory..

or if you want the supercharger, get the 03+ one..

 

[Jim Wyche]

IRS SWAP

If you will go with a Cobra IRS, here's how to do it:

http://www.mouthbreather.net/IRSSWAP.html

Have fun!