Author Topic: Craig, I checked the AOD/RPM's today (Read 334 times)

gwstang · « **on:** September, 14, 2011, 10:25:11 AM »

At 55 mph/1800 rpms
At 60 mph/2000 rpms
At 70 mph/2300 rpms

speed determined by gps.
15X6 craiger ss wheels.

Larry G · « **Reply #1 on:** September, 14, 2011, 01:29:36 PM »

Those numbers look great, I need an AOD!

lethal289 · « **Reply #2 on:** September, 14, 2011, 01:48:22 PM »

What gears and how tall of a rear tire?

tarafied1 · « **Reply #3 on:** September, 14, 2011, 02:29:09 PM »

thanks for the info, I need an OD too.

gwstang · « **Reply #4 on:** September, 14, 2011, 04:46:31 PM »

Quote from: lethal289 on September, 14, 2011, 01:48:22 PM

What gears and how tall of a rear tire?

3.50 gears

205/60R/15

gwstang · « **Reply #5 on:** September, 14, 2011, 04:54:49 PM »

Forgot to add one more thing. I have yet to get the correct frigging speedo gear (one that slides into the transmission) for this setup. I have changed the gear 3 times and it still reads faster than the gps says it is going. About 10 mph too much!

Also, I left the gps in the stang so I can keep up with the miles traveled and see what the mpg's will be. I filled up today and reset. Might take a little trip tomorrow to see what the damage is...lol. Ah heck, I can't keep my foot out of it anyway.

cmayna · « **Reply #6 on:** September, 14, 2011, 05:23:34 PM »

gwstang, is doing this exercise because he is running 3.50 gears in back. I'm running 3.0 gears in Red and I'm getting 2000 RPM at 70 mph. I was wondering what RPM those with 3.50 gears were looking at.

Jonk67 · « **Reply #7 on:** September, 14, 2011, 06:57:37 PM »

205/60R/15 would be a 24.69" tire ht., I take it your AOD is the standard 0.67:1 OD gear, 3.50:1 R&P.
Using an RPM calc. I get:
55mph = 1755RPM
60mph = 1915
70mph = 2234
I usually run between 70-80 on the interstate so I also punched up-
80mph = 2553

Not bad, that's within 45-85 RPM of your RPM's from an online calc., pretty accurate i'd say.
http://www.ringpinion.com/Calc_RPM.aspx
Craig, post your tire size also when you get your numbers.
I'm interested as i have the same AOD and gears but 1" taller 225/60/15 tires and haven't driven it yet.
All my RPM's come up 150 lower than yours, looks like I may need to step up to 3.73:1, I just don't want to be lugging right when it shifts into OD.
Jon

cmayna · « **Reply #8 on:** September, 15, 2011, 05:40:32 AM »

Red's rear tires are 225/60/15 = 25" diameter. With 3.50/AOD = 2305 rpm at 70 mph.

gwstang · « **Reply #9 on:** September, 15, 2011, 08:33:16 AM »

I was running the 225 tires, but with the gt lowering springs up front it kept dragging in the wheel well on tight turns or a hard bump. So, I went to the 205 the last time I got tires.

cmayna · « **Reply #10 on:** September, 15, 2011, 10:16:17 AM »

Well guess what, I'm running 205 on the front of Red as well. 225 in the back.

Jonk67 · « **Reply #11 on:** September, 15, 2011, 11:25:10 AM »

Craig, about what speed does it shift into OD, what RPM's are you at at that time/speed and does it feel as though it luggs at all? or do you get decent pickup without downshifting?
Jon

cmayna · « **Reply #12 on:** September, 15, 2011, 02:02:31 PM »

I really dislike the automated shifting point from 3rd to OD which is around 45. Shifts too early for me (don't remember what the RPM is at that point). Thus I normally drive around town in 3rd and when I realize I'm going to be jumping on the freeway or whatever, I'll hold it in 3rd until I get to 55ish, then pop it into OD. Still the tach needle drops down so far into the mid teens until I get up to 70ish. Again this is with the current 3.0 gears.