Bob Cosby's 12 Second recipe

Discussion in 'Fox 5.0 Mustang Tech' started by FastDriver, Feb 17, 2012.

  1. About 5 years ago, this was a common reference for those looking for how to make a stock fox run 12s. Somewhere along the line, it was removed from the web, but fortunately for posterity, I save helpful :poo: on the fox-bodies like a pack-rat. Now, those of you who've been around for a while know who Bob Cosby is. For those who haven't, he was one of the big names in fox-body performance since very early on in the 5.0 hey day. He was a national record holder in NMRA Factory Stock with both his '88 Fox-body, and also later on with his '99 Cobra (Black Cloud).

    So first up is his 12 second fox recipe:
    0 vmplaunc.jpg
    Running a 12.9 with a nearly stock 5.0 is not as hard as it might sound. The main ingredients are: a fairly lightweight 5.0, a motor in good tune, the right mix of bolt-ons, slicks, and very aggresive driving.

    Below is a list of mods, in no particular order, that I believe are capable of turning an average 5.0 into a 12 Second 1/4 miler. Keep in mind that this implies 12 Seconds on a drag strip, on slicks, not on the street on radials. Also, folks at a higher elevation will have a more difficult time breaking into the 12's:

    - 26x8 Slicks
    - 3.73 or 4.10 Gear
    - Short accessory belt
    - Off-road exhaust
    - Headers (prefer long-tubes)
    - Underdrive pulleys
    - Remove the air silencer
    - Ram-air/some sort of cold-air inflow, minimum K&N
    - If a Mass-air car, a larger sensor
    - 65mm TB with matching EGR plate
    - Remove front swaybar
    - Remove the clutch fan at the track
    - Advance timing to approx 13 deg
    - Good tune-up (new plugs, wires, rotor)
    - Remove all loose items in car (spare tire, jack, etc)
    -Courage. If you're scared of breaking it, you probably won't run the number!

    The key to a 12 second ET with a near stock car is getting the car to launch hard and performing very fast shifts. Initially, launch the car around 5000 rpms. Do a hard power shift in all gears around 5200 on the stock tach. Cool the upper plenum with ice before a run, and push the car through the staging lanes as much as possible.

    Some additional things that I would recommend include:
    -Boxed upper/lower control arms with urethene bushings.
    -Air bag in the passenger side rear spring.
    -Move the battery to the trunk/hatch area
    -Synthetic lubricants
    -Pro 5.0 shifter
    -Light-weight rims with skinnie front wheels/tires
    -Remove any weight you feel you can do without

    Some things I WOULD NOT BUY for a STOCK motor:
    -"off-the-shelf" chips (ADS, Hypertech, etc)
    -high-dollar spark plugs
    -aftermarket ignition systems (2 steps are nice though)
    -24# injectors

    I can't stress how important it is to get the car to hook and launch hard. The 60 and 330 ft times are by far the most important. Work on the launch and shifting, the ET's will fall. I have personally seen several 5.0's run in the 12's with similar mods to what I have listed. In my opinion, there is nothing extraordinary about any of them, or my own.
  2. Next up is the record he kept on his own notchback foxbody. Of note, I pulled this from his site on 7MAR01, but I think it was pretty much the end of the saga for the car:

    Options, Specs, and a Chronological list of Modifications (with ET)

    1 oldnice.jpg
    I ordered my 1988 Mustang LX Coupe from Hill Ford in Champaigne, Ill. in May of 88. I took delivery in June. Delivered price was right at $12,500. I didn't take a car off the lot because I wanted very specific options. This cost me a little more (mainly because I couldn't get the $500 rebate that was offered at the time), but was well worth it in my opinion.
    At the time, the 5.0 Mustang was THE CAR to buy if you wanted good performance at a low price. I have always tended towards acceleration vice handling. The best competition for the Mustang at this time was the Buick Turbo, although there were very few new ones to be found by the time I bought this car. Besides, they were over 17k new and I just couldn't afford one. I have no regrets!
    Here are the options I ordered:
    • 225 HP 5.0 H.O. Engine
    • Power Windows and Locks
    • Premium Sound
    • Cruise Control
    • Intermittent Wipers
    • Rear Window Defroster
    I ordered those options individually vice in a package because each available package contained something I did not want. Also, you might notice that I did not order A/C. That was intentional! I optioned the car this way in order to have a decent daily driver that was light and powerful.
    Below is a chronological list of mods, and what the car ran with the addition/deletion of those mods...

    - Pure Stock except M/T Indy Profile S/S G60-15's, Microburst Computer Module. July 88, Indy Raceway Park - 14.07 @ 99 mph.

    - Off-road exhaust with mufflers disconnected, removed front sway bar. Great Lakes Dragaway (Union Grove Wi.), Sep 88 - 13.75 @ 100 mph.

    - Underdrive pulleys, 160 deg Thermostat. Great Lakes Dragaway, Oct 88 - 13.54 @ 101 mph with a best ever on street tires 1.91 60 ft (still stands to this day for me!).

    - 26x8 Goodyear slicks. Coles County Dragway (Charleston Il.), Nov 88 - 8.28 @ 83 mph. NOTE: I didn't ever get to a 1/4 mile track in this configuration, but an 8.28 should be in the high 13.1 or low 13.2 range.

    - 3.73 gears, short-belt. Great Lakes Dragaway, Mar 89 - 12.99 @ 103 mph. NOTE: My first 12! I was estatic, and was able to back it up with a 13.000 on the next run.

    - Bumped timing to 14 deg. Great Lakes Dragaway, Jul 89 - 12.93 @ 103.5 mph.

    - Homemade Ram-air. Texas Motorplex (Ennis, Tx.), Sep 89 - 12.83 @ 103.5 mph. NOTE: Very good air this day. That ET would be my best until Aug of 1994.

    - Air bag in passenger side spring, moved battery to the trunk. Great Lakes Dragaway, summer of 90 - ran a best ever to date 105.2 mph.

    - Borrowed 65mm TB from Rick Anderson. Coles County Dragway, Nov 90 - 8.03 @ 84 mph. NOTE: That should equate to a low 12.7 or high 12.6 run. This was my last time at the track until 1994.

    - Full-length 1 5/8ths headers, 65mm TB, Zoom Kevlar Clutch, Z-code (2.95 1st gear) T5, Hurst Shifter. Virginia Motorsports Park, Aug 94 - 12.70 @ 106 mph.

    - No changes. Virginia Motorsports Park, Nov 94 - Back-to-back 12.52 @ 106.9 mph, 1.67 60 ft. (7.93 @ 85 mph 1/8th) *****This stood as my all time best until Nov 97*****
    2 12_52.jpg

    - SSM Lift bars, subframe connectors, manual steering rack, FMS Heavy Duty clutch. Old Bridge Township Raceway Park, Englishtown, NJ, Sep 96 - 12.70 @ 108.1 mph. NOTE: I went back to an FMS clutch because I didn't like the Zoom Kevlar on the street.

    - No changes. Virginia Motosports Park, Oct 96 - 12.68 @ 108.32 mph. This was my best ever mph until Nov 97.
    3 108_32.jpg

    - Big Experiment! TSI prepared, race-ready AOD with a Precision Industries 9.5" Stallion Torque Converter. Hub City Dragway, Ms, Jan 97 - 13.00 @ 101.9 mph, 1.71 60 ft. NOTES: I tried something different. I was tired of missing a gear at the wrong time, and well, like I said, wanted to try something different. This is the best run I made with the AOD. Most runs were 13.1-13.2 @ about 100 mph. I incorrectly thought that the converter might be too loose for the stock 5.0, so I had P.I. tighten the converter (no charge) and tried again. I slowed about a tenth, all of it in the first 60 ft. I honestly believe that this tranny would have been OUTSTANDING behind a blown or well-built engine. TSI built it to handle a 10 second car. Bottom line, I really loved it, but just couldn't handle the 4-5 tenth drop in performance. So.......

    - Used Z-code T5 and FMS Heavy Duty clutch. Virginia Motorsports Park, Mar 97 - 12.95 @ 106.1 mph.

    - Ram Kevlar Clutch. Rockingham Dragstrip, Rockingham, NC, Apr 97 - 12.66 @ 106.8 mph.

    - 4.30 gear, M/T 28x9 slicks, BBK boxed upper and lower control arms (ditched the SSM's). Maryland International Raceway, Budds Creek Md, Aug 97 - 12.63 @ 104.9 mph w/ 1.63 60 ft. (7.97 @ 84 1/8th). This is my best ever 60 ft. This run was through the Mufflers. NOTES: As you can see, I stepped up big in the gear and tire department. I was very happy with that time, considering I had to run corked up and it was very humid that evening. I believe a 12.4 might be in the cards this fall.
    4 12_63.jpg

    - No Changes except disconnected the Exhaust just in front of the mufflers. Virginia Motorsprots Park, Sep 97 - 12.55 @ 105.89 w/1.65 60 ft. (7.94 @ 85 1/8th) NOTES: This was my last outing before the bearings started to make noise on my original 120k+ engine. I had hoped to break my long-standing 12.52 record, but it just wasn't to be. I made 5 passes that day, all of them between 12.550 and 12.572.

    - Ported stock heads, ported stock intake with extrude-honed upper, custom Competition Cams camshaft, C&M Racing/AutoLogic chip, 24 lb injectors, 1.6 roller rockers. Maryland International Raceway, Budds Creek Md, Nov 97 - 11.93 @ 110.18 mph w/ 1.58 60 ft. (7.55 @ 89 1/8th). NOTES: This is a goal that I had set for a long time. I was ESTATIC when Mike Wamsley stopped me before the timeslip shack and told me what the car had ran! Backed it up that day with an 11.96 and 11.97.

    - Competition Cams 270HR Camshaft. World Ford Challenge in Bowling Green, Ky. May 98 - 12.34 @ 105.89 mph w/1.66 60 ft. NOTES: run through the mufflers and stock tailpipes. This time qualified me #6 of a 16 car field in Pure Stock. I was over-geared with the small camshaft, but it was necessary to fit the Pure Stock Rules.

    - INCON Twin turbo system set at 8 psi boost, Mass-air conversion, Tremec TKO, 6 pt rollbar, 3.73 gears. Removed race underdrive crank pulley. Beech Bend Raceway Park, Jul 98 - 11.57 @ 121 mph. NOTES: granny shifting, slipping the clutch. All the mods added about 200 lbs to my car. There is several tenths and a few mph left in this trim. I expect low, low 11's and about 124 mph in the near future.

    - No Changes, except a much stickier track and a little more experience behind the wheel. Maryland International Raceway, Aug 98 - 11.05 @ 123.49 mph. NOTES: Had a pretty decent 1.51 60 ft time. Very little clutch slippage, hard shifting, but still not a real power shift. Probably another tenth or two just in driving.

    - No Changes, except a little more experience behind the wheel. Virginia Motorsports Park, Sep 98 - 11.00 @ 124.20 mph.
    Lentech AOD, Canfield heads, Holley Intake. 9 lbs of boost, ET Streets, pump gas. MIR, Sep 99 - 10.922 @ 126.14 mph w/1.66 60 ft. NOTES: Left at 3k and about 2 lbs of boost - spinning the tires.
    Last, but not least, here is the complete list of mods my car had went it was running very streetable 10.9's:
    • FlowTech Induction Systems Prepared Canfield heads with 1.94/1.60 valves
    • FlowTech Induction Systems Prepared Holley Systemax upper and lower intake
    • Competition Cams 270HR Camshaft
    • INCON Twin Turbo Kit. Includes:
      - Twin Turbo Chargers - 9 psi
      - Intercooler
      - Calibrated 80mm Mass-air Tube
      - 36# Injectors
      - 255LPH Fuel Pump
      - Mounting hardware
    • 2.5" Off-Road Exhaust
    • Dynomax Race Magnum Mufflers & 3' Tailpipes
    • BBK 65mm Throttle Body and EGR Plate
    • FMS 8mm Plug Wires
    • Lentech "Strip Terminator" AOD
    • Custom 6 pt Rollbar
    • Weld Draglites 15x8 (255/60R15) 15x3.5 (165R15). On the track, I used 28 x 11.5 x 15 ET Streets.
    • 3.73 Gear
    • Motorsport Aluminum Driveshaft
    • Manual Steering Rack
    • 4 Cyl Front Springs
    • BBK Boxed Upper & Lower Control Arms with Urethene Bushings
    • Air Lift Air Bags in both rear springs
    • Removed front swaybar
    • Battery relocted to trunk
    • Lakewood 90/10 struts and 50/50 shocks
  3. EXCELLENT POST. I feel so silly not being able to get in the 11's with heads, cam, and intake :(
    michaelgt likes this.
  4. Now, his on track tips:

    Some Tips, Some Tricks, Some Things I do at the Track... 5 tips.jpg

    First, don 't go to the track with unrealistic expectations. There are way too many variables in drag racing that will keep you from accurately predicting your ET. Some of these are wind, track elevation, weather conditions, track conditions, time of day...the list can be rather long. Go into the race with an open mind and learn. Your ET's will go down with practice.
    Make sure your car is in good tune: make sure you have good plugs, wires, ignition. Inspect the tires and make sure your brakes work well. Check the oil, change if necessary.
    Make a list of things you will need to take. A short list might include: helmet, long pants, tire gauge, a set of tools, a portable air compressor or air tank, garden sprayer (for cooling the engine), lawn chair, small cooler with drinks and a snack (food and such is usually fairly expensive at the track), sun block during afternoon races. The time to remember you forgot your helment is NOT at the staging lanes! Also, have a contingency plan in mind in case you break. I go to the track EXPECTING to break.

    If you are driving your car to the track, plan to get there with as little gas as possible. Gas weighs over 6 lbs a gallon. Weight is bad. Also, if your car is stock, don't put straight racing gas in it, chances are it will slow down. This is because those super-high octane fuels need high compression to make em burn. It might be ok to add a gallon of 100 Octane unleaded just to guard against detonation, but don't burn it straight.

    Take everything that is loose out of your car. Things like the spare tire and jack, that cooler you brought, and your 100 pack of killer CD's. Get the weight down!

    At the track, air your front tires up to 10 lbs over the max as this will reduce rolling resistance. BUT, make sure you bring the pressure back down before you get back on the road!
    Heat (in the intake portions of the engine) is bad, it kills power. If you want maximum ET's (especially from an EFI car), set a bag of ice on the intake for a half hour between rounds/time runs. Also, buy a garden sprayer and use that to cool down the radiator. When my car was mostly stock, I would often finish a run, leave the car on, and start hosing the entire engine. After 15-20 seconds, I'll kill the engine and continue to run water over things for about 5 minutes or so until the engine is good and cool. I would NOT recommend doing this with a blower or turbo.

    If you are bracket racing, the above should be done with caution. This is because the name of the game in brackets is consistancy. You can't be consistant with a cold intake/motor on one run, and a hot intake/motor on the next. I would advise to just pop the hood and let the car sit vice any sort of extra cooling.

    You might try removing the clutch fan if you car is so equipped. It takes quite a bit of HP to turn that thing at high speeds, and it is not necessary at the track, so long as you don't sit and idle. I have recorded a .05 sec drop in back-to-back runs just by pulling the fan.

    Speaking of idling, don't! If at all possible, push the car through the staging lanes. Most Mustangs aren't heavy, and I for one need the exercise! Turn the engine off whenever you can. I routinely turn it off as I coast through the pit area towards my stall. I only start it when absolutely necessary. Excess heat is bad!

    If you are racing on real radial street tires, don't do a big burnout like the guys on slicks do, you will only waste tread. I pull around the water box, back up to NEAR the water, and spin the tires a second or two in 1st gear. Then it is off to the staging beams. Try various launching techniques for the lowest 60 ft times. Practice, practice, practice.

    A word about launching: A set of slicks is the only way to get good ET's. Cheaters are neat, drag radials are ok, but nothing hooks like a proper set of slicks. When using them, keep the air pressure as high as you can to reduce rolling resistance. Start with maybe 14 lbs and see how it hooks. If you hook, increase a couple of pounds. If not, bring it down a couple pounds until you do.

    A race is won and lost in the first 60 ft - 330 ft. This is where you want to concentrate on making your improvements.

    Time to stage. Roll very slowly in the middle of your lane towards the beams, making sure your car is pointed straight down the track. Stop when you light the pre-staged light. Then as slowly as possible move forward until the staged light illuminates. You want to stage as shallow as possible for best ET. That extra 1 or 2 inches that a really shallow stage will get you can add up to a hundreth of ET at the big end (wouldn't you rather run a 13.999 than a 14.000?). The first time you launch, leave as soon as you see the last yellow light come on. That should be a pretty fair reaction time, and will give you a base to build on. Remember though, reaction time is necessary to win races, but not to get a good ET.

    Once you have the car launched, a good, hard powershift (for stick cars) is going to produce the best ET's. This means using the clutch, but not letting your foot off the gas. With sticky tires, I've seen 2 to 3 tenths improvement in powershifting over granny-shifting.

    Experiment with your shift points (both stick and auto). Most people seem to have a tendency to over-rev stock or near stock 5.0's, and under-rev the new 4.6 motors. Talk to people that race your type of car and get a good starting point from them. Then go out and find where you car likes to be shifted, which requires time, patience, and good record keeping.

    Did someone say record keeping? This is something that many people over look, but can be very valuable. I would make a log with several columns: Date, place, time, weather conditions (hot/cold, humid/dry, barometer, wind), 60 ft times, 330 ft ET, 660 ET and mph, 1000 ft ET, 1/4 mile ET and mph, and a comments section to record general impressions of the run, any changes that were made and their effect, other pertainent data (my best run ever!). Why do all this? Lets say you added a set of underdrive pulleys this week, go to the track, and your car slows down. Why? If you kept a good log, you would know if it was the weather, traction, headwind, etc. Maybe your 60 ft times were worse and your mph was better? Sounds like that extra HP is going up in smoke at the starting line. The only way to really see this is to keep a good log.

    If you break something relatively small and need some help, or need a part, a quart of oil, etc, ASK! Most folks at the track will go out of their way to help you. Just make sure you are willing to do the same when someone needs your assistance.

    When its time to pack up and go home, make sure you got all your stuff back together, Let the extra air out of your front tires, put a little air back in your rear tires (if you took some out), hang on to those time slips, even the bad runs can tell you something! Pick up around your pit area, the track guys will really appreciate this and will be glad to see you come back.

    Most of all, have fun! The drag strip is a great place to go unwind and beat up your car, legally!
  5. Man... Too bad Incon is not around anymore. They were the only CARB legal turbo kit for California...
  6. Good post, Chris! I have to say, I'm kind of surprised that he didn't say anything about running lightweight drag wheels. Running stickies in the back with skinnies in the front is huge!
  7. Nik, see first post under "some additional things I would recommend."
  8. Awesome post, this should be stickied so it dont drop off and disappear. reading this reminded me of when I first got my car back in the mid 90's, some of the :poo: ive seen people doing at the track.
  9. Anyone remember the name Ed Hohenberg??? I grew up reading about Ed in Muscle Mustangs...........I believe he still occassionally writes articles for them. Anyways, great guy and he does a great job tuning here in Canada.


    "Ed Hohenberg has been successfully drag racing the "Monolith" in NHRA Stock and SuperStock since new. The 1987 Mustang LX was ordered specifically for drag racing, including the rare radio delete, and vinyl interior options. Best performance was achieved at the 1998 US Nationals, where the car broke into the 11 second range in NHRA L/Stock trim. "
  10. I remember the name.
  11. D'oh! Long week at work I guess. Faildozer on reading comprehension.