Michael4yah,
Even though I took a 9" OEM rear housing and split or twisted it in half I would definately still go with a 9". Only one of the after market ones that have a full guarantee for racing. The OEM Viper 3rd member aint gonna fit and it will drive you nuts for suspension!
Stock motor location: When we built the next generation of DV's our weight ratios with 187 lb driver, with absolutely everything, turned out within 1% of "X-ing" out at 50%. Front to rear was 49% front w 51% weight to the rear- we could only make it worse so we didn't try anymore.
Remember the ENTIRE V-10 motor with, half bellhousing, flywheel, clutch,starter, alternator* serpentine belts everything bolted to the motor weighed in at 611lbs. Almost 100 lbs lighter than a Ford 351 minus the entire bellhousing-clutch assembly, intake carb, distributor, alternator, starter etc. In other words hundreds of lbs lighter than a basic 351 full motor!
Bottom line measurements, personally with your type Cobra I would locate the mounts in the exact place or set the motor back no more than 3/4".
Drive Shaft: We used the Viper drive shaft which was recut, balanced under water no less, and rewelded by Spicer. Thank you Spicer! The OEM drive shaft works very nice and if I remember correctly (Don't count on that these days!) our shaft ended up being around 18"s OC-'U'-joints. My thoughts on a drive shaft being to short is hog-wash. To me it only means the guy that put it in didn't read his gauges right and got the shaft in to far off set.
Pinion angle- I think with the monster torque we were putting out we used rougly a 1.5 degree down angle on the pinion at "parked".
Headers-you will have to make your own headers I know of no Cobra frames that will allow OEM Viper manifolds-BUT with our headers and sidepipes and dyno'd multiple times our DV's constantly put out around -believe it or not- 427 to 435 horses at the wheels!
OIL PAN- Boy did I learn that one the hard way! On the skid pad when Roger was pulling 1.3G's plus we burned up #3 bearing. The Viper holds 11 qts in a very special, basically flat
oil pan. At the 1.3G's all the
oil is forced into a valve cover starving the crank bearings! (I did call Viper immediatley after the problem and they told me or asked me how in the hell did I get over 1.3Gs out of a cobra KIT? They new at 1.3 and above the Viper motor needed oiling help!) Solution is two fold, a very simple one is to remove the oil pan, (very simple process-even in the car) study the design for a minute then you will understand what I am saying. Put a small swing door inside on each end of the middle- when the cars starts a hard trurn the doors will swing closed keeping the oil in the pan! Very simple, cheap and it works!
OR spend the money and work and go with a dry sump- it works!
Suspension: Front suspension was a standard CR II front suspension. I used 450 lb coil-over springs up front (we did try 4 different spring settings) Tubular front control arms.
Sway bar: Depending on the track we took it off or hooked it up. On some tracks it even slowed us down ??
Rear, again was Dons supplied 250/350 lb coil-overs-no sway bar at all!
WIRING: Boy Dodge has made it tough for us now-they finally relented for us and made it very easy then when Gen3 motors came out they basically slammed the door shut in our face.
You MUST use all 4 02's at this point OR contact John Spina-Caspers Electronics in Chicago. John is a major Cobra player, freak when it comes to ALL type of wiring and knows everything there is to know about ECM's. 02's etc.
I would suggest one thing, if your going to do this project use a GM one wire alternator. Very simple to adapt AND it eliminates an entire wiring nightmare. The ECM in a Viper wants to know battery temp. (two more wires) Idle output of the alternator, middle speed and high end output. If you eliminate it all by going with the GM it's done in ten minutes!
Speeds: Problem; fella with Rogers help and any "Pro" can do the same thing, the car obviouslyu handeled like a true dream at all speeds! Our only problem was at the 157 mark the nose wanted to dangerously lift or become airborne. A much needed front wing/spoiler was absolutely necessary above 140! Of course I don't think that had anything with being a DV I think it was because it was a Cobra!
A war story! Jerome Kowalik, out driver at Run N Gun in St. Louis over powered the DV in the chicanes loosing control and almost hitting the wall! Scared me to death but not Jay, he ended up facing the wrong way, dumped the clutch, spun the car around-never- leaving the track- and continued on his way still winning our class by 2 + seconds!
Yep, I do love those cars! Keep my number-I can talk a heck of a lot easier and faster than I can type!
Ed/DV Combs