Should I put it in overdrive for a dyno pull? September 30, 2007, 04:01:32 PM Got a dyno run scheduled for Tuesday, my first one and the car's first too I imagine. Anyway after reading it on coolcats I started running my AOD in Drive rather than Overdrive unless I'm gonna be on the highway for a while. In Drive I've found the car feels much stronger, I don't know if that's by design or if my overdrive band is just screwed. My first instinct is to make this run in Drive but I've never really pushed the car to the limit in Drive before, should I have any reservations about it? Quote Selected
Should I put it in overdrive for a dyno pull? Reply #1 – September 30, 2007, 04:27:57 PM yes, OD would give the tranny a 1:1 ratio, for the numbers to be accurate. Quote Selected
Should I put it in overdrive for a dyno pull? Reply #2 – September 30, 2007, 04:33:17 PM Quote from: 32VFoxBird;179854yes, OD would give the tranny a 1:1 ratio, for the numbers to be accurate. I'm not 100% positive, but OD would actually give you <1:1 ratio since it is OVERdrive, where Drive is 1:1. One more thing that I'm less sure of since I've never been on a dyno before, but I'm not sure it would matter if you had it in OD anyway since I doubt it would ever shift up to OD, especially since you would be pushing it at WOT. Hopefully someone else will chip in and tell me I am correct (or completley refute me :) Quote Selected
Should I put it in overdrive for a dyno pull? Reply #3 – September 30, 2007, 05:37:58 PM I believe final drive for OD gear in the AOD tranny is a .75:1 ratio not 1:1 Seems it’s 1:1 in drive and .75:1 in OD… I’ll see if I can find the info someplace From" http://www.thepontiactransampage.com/transgears.html"Ford AOD 4-spd automatic2.40, 1.47, 1.00, 0.67" From: http://realbig.com/detomaso/1998-02/266.html "If better acceleration is the goal, a ring and pinion swap may be in order.The beauty of this swap is that the AOD's 0.67:1 overdrive ratio can makea" And finally from: http://lists.twistedpair.ca/pipermail/classic-mustangs/1996-December/000644.html " Ford Transmission Ratios ------------------------ Stock Stock WR Stock WR E4OD C4 C6 C6 AOD AOD 1st 2.46 2.46 2.72 2.40 2.84 2.722nd 1.46 1.46 1.54 1.47 1.55 1.533rd 1.00 1.00 1.00 1.00 1.00 1.004th ---- ---- ---- 0.67 0.70 0.71" I was off... .67 not .75 but still not 1:1 Quote Selected
Should I put it in overdrive for a dyno pull? Reply #4 – September 30, 2007, 05:38:16 PM Quote from: SSX;179855I'm not 100% positive, but OD would actually give you <1:1 ratio since it is OVERdrive, where Drive is 1:1. One more thing that I'm less sure of since I've never been on a dyno before, but I'm not sure it would matter if you had it in OD anyway since I doubt it would ever shift up to OD, especially since you would be pushing it at WOT. Hopefully someone else will chip in and tell me I am correct (or completley refute me :)correct, i was wrong. trans needs to be in 3rd gear. OD is a 0.67:1 ratio. Quote Selected
Should I put it in overdrive for a dyno pull? Reply #5 – September 30, 2007, 05:39:34 PM Quote from: Jim_Miller;179861I believe final drive for OD gear in the AOD tranny is a .75:1 ratio not 1:1 Seems it’s 1:1 in drive and .75:1 in OD… I’ll see if I can find the info someplacehttp://www3.telus.net/cbradley/Drivetrain_Ratios.html Quote Selected
Should I put it in overdrive for a dyno pull? Reply #6 – September 30, 2007, 05:46:38 PM Great info, thanks guys. Quote Selected
Should I put it in overdrive for a dyno pull? Reply #7 – September 30, 2007, 11:24:54 PM NO O/D on the dyno!!! EVER!!!Most older design trannys are very weak in O/D, usually the owners manual even says not to tow using O/D... Now you know why... Quote Selected
Should I put it in overdrive for a dyno pull? Reply #8 – September 30, 2007, 11:37:56 PM Not to hijack,but should I have the tranny in Drive instead if oerdrive most of the time,like "in town" driving? Quote Selected
Should I put it in overdrive for a dyno pull? Reply #9 – September 30, 2007, 11:41:52 PM It's mentioned on Coolcats that experienced tranny guys recommend keeping it in Drive unless you're going to be driving it at high speed for a length of time. It's actually better for the transmission and fuel economy. I started doing it a while ago and I find the car more responsive. Try it. Quote Selected
Should I put it in overdrive for a dyno pull? Reply #10 – September 30, 2007, 11:57:08 PM Quote from: vinnietbird;179942Not to hijack,but should I have the tranny in Drive instead if oerdrive most of the time,like "in town" driving?Too hi jack even further.. I do that.. if I'm in town I always put the car in drive instead of overdrive. Especially on the older non electronic AOD's. I turn off the O/D on my Mountaineer too in town. Quote Selected
Should I put it in overdrive for a dyno pull? Reply #11 – October 01, 2007, 12:52:06 AM Basically if youre in town chances are youre gonna be cruising at around the speed it shifts into OD, and if youre hovering around there its probably gonna be constantly shifting between 3rd and 4th, so you might as well save the trans a lot of work and keep it in 3rd. Also allows the engine to stay at an rpm where its happy speeding up and slowing down. Quote Selected
Should I put it in overdrive for a dyno pull? Reply #12 – October 01, 2007, 07:59:17 AM Quote from: bhazard;179957Basically if youre in town chances are youre gonna be cruising at around the speed it shifts into OD, and if youre hovering around there its probably gonna be constantly shifting between 3rd and 4th, so you might as well save the trans a lot of work and keep it in 3rd. Also allows the engine to stay at an rpm where its happy speeding up and slowing down.I agree. My Titan has a five speed auto in it and I keep it out of overdrive unless I am on the freeway. Or a road that doesn't have many stops. Trans coolers extend the life of a transmission as well.Brian Quote Selected
Should I put it in overdrive for a dyno pull? Reply #13 – October 01, 2007, 08:57:01 AM My '88 won't shift into O/D till about 50mph... With 3.73 gears, thats perfect(good thing, I have no way to lock it out, D is 1st & 2nd only)... That ed '95 thinks it has to be in O/D at 35mph, with the 3.08 gear that sucks, so yup It's generally off in town... Quote Selected
Should I put it in overdrive for a dyno pull? Reply #14 – October 01, 2007, 01:04:23 PM My 83 and 88 (when auto) would shift into O/D at about 35mph.. The speed limit in town is 35mph so I would be in and out of O/D constantly so I saved the transmissions and kept them in D. Quote Selected