Was using a 3 speed on my truck last year but with no OD. It was singing around 3200rpm to just do a bit over 60mph. I got a fairly recently rebuilt t-5 that is from a 85 s-10 with tag number 146. The 150 tag is listed as having ratios of 1st. 4.03 2nd. 2.37 3rd. 1.49 4th 1.00 5th 0.76. Currently have a 3.73 ratio rear end installed. Attached are a few sheets I printed with different T-5 transmission tag numbers. I currently own the tag #146 but can also get my hands on tag number 072 and swap its guts into the s-10 t-5. What you guys think of the different ratios and what t-5 I have currently purchased ? Using a 1955 235 with some goodies installed.Will possibly install a new bulldog or similar cam this summer but for now still getting the torque from the 1800-2200 area. Tag #146 Tag #150 Tag #072 Oh and my current 3 speed setup is listed below
A lot of gear space on first to second gear. This is a 4 cylinder trans most likely. You have plenty of torque to pull a taller first gear and those ******s will take more torque than the low geared ones. Why not change your rear end ratio to 3.50 or some thing taller than 3.73 or run taller tires. Jim Ford
Those ratios will be fine. It will be good off the line, and fine one the freeway. If it were me, I would find the S10 T5 with the 3.76-0.72:1 ge****t. The gear spacing is a little better. That 072 unit has the V8 5.0 ge****t. You DO NOT want that. The gears are way too tall for a small 6.
The #146 transmission that i got is from the v6 model. Changing the tries is something i don't wish to do as they are all new. I was thinking about changing the rear ratio to the 3.42 offered for the GM 7.625" rear end i have. I also see a listing for one 3.55 ratio setup but i need to confirm the exact details of my rear end to see if that one will fit it properly. Thoughts on the #146 t-5 now combined with a 3.42 rear ratio?
A .76 OD ration with a 3.42 rear axle ratio will be the equivalent of a 2.60 final drive. Pretty tall for a 235 Chevy 6! An upper 3 to low 4 rear end would work better for highway cruising. Ray
Guess what im really after is opinions on the ratios of the #146 I just bought if i used it with my current rear end and tire sizes. I was using toms chart but it has conflicting info. I'm ***uming he is using the stock tire size that i think comes in at 28" tall unlike my 25" tall ones. His A- rating has a first ratio of 14.02, the B+ has a first ratio 14.3. His other tech article on his site says a first ratio of 12 is desired, 10 requires slipping and 15 is going to get annoying. Currently my first ratio is 10.6 with the 3 speed but changing to the t-5 #146 will put me at 15.03. The truck does not have that much of an issue now taking off because I am sure the smaller dia tires are helping me out. I am ***uming a 10:1 ratio for first as tom notes is probably an issue for taller tires. I chew thru the gears so fast as it is now im in third as i just drive down the street. Granted i can just stuff the t-5 in the truck but im trying to get a proper handle on this prior to the install so i can make changes to the ratios now and not have to drop the trans again later.
There will be views all over the place on this issue, but to me the 2.95 T5s with a 4.11 rear end gear and a .63 OD it the way I am going. I am putting the thing in there to drive, Hot Rod style, not just to let it get around with a lot of h***le. You need gear ratios as close as possible, wide ratio transmissions are for old ladies and heavy underpowered trucks and anything near a high performance car.
33 5w coupe, 48 59a flathead engine, Ford T5z, v8 type quick-change rear axle, 31 inch diameter rear tires.
Whatever you choose to run, run the numbers before dropping the cash. A 235 won't enjoy being under-revved
Might start by working it backwards. What rpm do you want to run at and at what speed? Say something like 60 to 70 mph and say 2000 to 2500 rpm. Select your tire size and see where your at as far a rear end gearing goes. Big difference between the .63 and the .76. Decide what speeds and rpm you can live with. I know everyone wants the lowest rpms possible for fuel economy, but you also don't want to have to shift in and out of 5th gear every time you slow down a little or have a hill to climb. Interesting story. Had a new 2005 mustang GT that developed a gear whine so had the dealer replace the ring and pinion. As long as I was changing it I decided to drop the gear down. The mechanic at the dealer raced mustangs and wanted me to go with a 4:10 but I drive on the highway a lot and was concerned about the mileage, so went with a 3:73. They insisted a 4:10 was better. Well, with the 3:73 my in town mileage went up a lot! and even my highway mileage with up a little. Should have went with the 4:10!!! But even the 3:73 made a world of difference in the performance of the car. Gears are where it's at performance wise.
It would be nice to know what RPM at peak engine torque. If you could set your highway cruising speed there you would get maximum MPG and performance.
Im thinking just like you Jim I took 3 of my graph charts from above and marked them up a bit with some more info. I dont think i mentioned that the T-5 i already bought with the #146 tag i only got for $50. Its in perfect shape and needs no servicing. I would like to stick with it if possible and maybe take in to consideration changing out the rear end ratio to possibly a 3.43 to help things out. A rear end kit is only $180 ish and im ok with that because i dont think i will find a ****** around here for near $50 again lol. Other used ones are selling between $850-$1200 with a different ratio but the wrong housing. I can always visit that idea later. Aslo I am in Canada so im going to start talking in kph and marking my graphs in such. Basic speeds posted on my travels are 30,50,60,80,100,110. 90% of my driving is the 30 to 80 range. My engine torque curve is in the 1800-2200 area with the stock cam. Thinking about changing that out possibly this year or next so that rpm range will move up altogether a bit. Chart with the current 3 speed and 3.73 rear ratio. You can see here when doing 30kph im either at 2800rpm in first or 1500ish in second. 50km im at 2800rpm in second or 1600ish in third. 60km is 1800ish rpm, 80km is 2500rpm,100km is 3200ish rpm. Chart with the T-5 #146 speed and 3.73 rear ratio. Chart with the T-5 #146 speed and 3.42 rear ratio.
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