It's aliiiive! After undergoing a radical drivetrainectomy, my 99 is back on the street. The tranny/gears: I upgraded to a Viper T56 from D & D performance. 1st and 2nd gears on a T56 are taller than a T45, so it takes at least 4.10's to avoid losing low speed torque. I went with 4.56's, and they rock. The Viper T56 has a taller 6th gear than the Cobra T56, so my highway engine rpms are no higher than they were with stock gears. The gear ratios are closer than the T45 for the first 3 gears. RPMs don't drop as much as they used to between shifts. This tranny is really going to keep my engine in the sweet spot on the track. I didn't bother to wire up the reverse lockout switch. It just takes a little bit of extra effort to get the car into reverse. It's not much at all. The half shafts: I upgraded to 03 half shafts. The 99 Cobra has a 28 spline axle as opposed to the 31 spline on 01 and 03 Cobras, so I had to swap out the carrier as well. Bushings/brace: I went with Steeda IRS bushings and a Maximum Motorsports pinion nose brace. Wheel hop is GONE! I can't wait to get everything broken in and hit the track for new 60' times. Driveshaft: The D & D conversion kit comes with a custom aluminum driveshaft. I have no drivetrain vibration problems. Clutch: The Viper T56 has a 26 spline input shaft as opposed to the 10 spline on stock Cobras, so a factory clutch won't work. I chose an Apex Motorsports dual kevlar unit. Pedal pressure isn't much higher than stock. There's much less gray area between "on" and "off", but it's still very streetable. Midpipe: The crossmember included with the D & D kit is much thicker than the stock crossmember and sits further back, so my MAC prochamber won't line up with my catback anymore. I bought a new MAC catted H to replace it. It fits, but it's WAY too low to the ground. I can't drive over the slightest speed bump without scraping. It will take a bit of work at a muffler shop to put it back where it's supposed to go. The catted H doesn't have the unique sound of a prochamber, but I'm quite impressed nonetheless. It screams American muscle through my flowmasters. I'll be in for a dyno tune in a couple of weeks, and I'll see if it makes as much power as the prochamber. Aric at Team Ford of Marietta performed all the work, and I'm extremely impressed with their customer service. They even washed my car before returning it. Aric will be dyno tuning the car with Super Chips software once I get the tranny broken in, and then it will be off to the track for some new personal bests.
Thanks for the update, Sanchez. Mine goes in the shop this coming Thursday for the swap. I went with 4.10's in the rear end as I plan to S/C in the future.
Oh don't waste the money on the 4.10's even S/c, get the 4.30's you will not be disappointed with them!
Im am intersted in doing the 31 spline conversion on my 99 cobra. All you had to do was change the carrier and the halfshafts? If there was anything else how about let me know. I busted my diff at the track last weekend so im looking to upgrade it, thanks
Ya, I finally got my car on the road after all winter (Viper T56 went in right before storage). The RPM's only drop like 2500 RPM's when shifting at redline...so it's right in the powerband whenever you shift. FUN. Same...no big deal. I'm in reverse for 3 seconds, so who cares. I have the 4.30's....FUN. I just got my 295/35/18 BFG DR's put on....one more word. FUN. I actually can hook in first gear with no wheel spin when hammering it from a 5mph role. Glad to see it's finished Sanchez.
You and me both! It's great to be back behind the wheel after driving my old cherokee for a month. I noticed one more happy side effect of the swap: The gear shifter is a bit forward and to the right of the stock location, so 2nd gear doesn't knock cups out of the front cupholder anymore. Sweet.
