| Author | Message | ||
| Jim Wilke (Jim Bob) (Pd41044039)
Registered Member Username: Pd41044039 Post Number: 367 Registered: 2-2001 Posted From: 69.77.157.8 Rating: N/A |
What transit coaches use inline 6-71T or TA engines with automatics? Thinking of an upgrade powertrain for a 4104. | ||
| Jim Gibson (River_rat)
Registered Member Username: River_rat Post Number: 64 Registered: 1-2009 Posted From: 75.95.96.192 Rating: N/A |
Not a transit, but Crown's used 6-71 pancake (same engine, just laid on it's side) and Allison 4 speed in the 70's. Great buses, for a Skoolie Jim | ||
| RJ Long (Rjlong)
Registered Member Username: Rjlong Post Number: 1568 Registered: 12-2000 Posted From: 98.192.173.82  Rating: N/A |
Jim - Los Angeles RTD had a bunch of Flxible Metros with 6-71T / V-730 powertrains. Don't recall if they were DDEC/ATEC or not. . . Very underpowered in a 40-foot coach. These were also wide-body buses, so the engineers had an additional 6 inches to work with getting the drive line angles correct, something that may be a challenge in the 96" '04. You could try Nick @ Nimco, or possibly Pedco in S CA to see if they have any take-outs. The Crowns used a RH engine, so that's out except as a parts source (turbo, oil lines, etc.) There are two or three '04s running around that I know of that have 6V92TA / V-730 / 4106 axle powertrains. Talk about hot rods! FWIW & HTH. . .  | ||
| Jim Wilke (Jim Bob) (Pd41044039)
Registered Member Username: Pd41044039 Post Number: 368 Registered: 2-2001 Posted From: 69.77.157.8 Rating: N/A |
Gee RJ, could they be as underpowered as a non turbo two valve (170hp) 6-71 with 3.55 gears? I wonder what the HP is on those Flexes. | ||
| Bryan Larrabee (Busasaurus)
Registered Member Username: Busasaurus Post Number: 15 Registered: 12-2000 Posted From: 24.84.136.155  Rating: N/A |
I believe the New Flyer D700, D800 and D900's were T drive and automatics. There are even some D900's still in revenue service. I think the AM Generals were equivalent to the D700's. | ||
| john w. roan (Chessie4905)
Registered Member Username: Chessie4905 Post Number: 1491 Registered: 10-2003 Posted From: 71.58.110.9  Rating: N/A |
If you try to hook a v730 to the end of a 6-71, it will stick out of the side of the coach some. The best deal is to buy a 6V-92 with auto attached from Nimco or other dismantler. You'll need to change or modify rear axle as the drive shaft angle and differential placement on the housing is different. Also, a larger radiator would be needed. The overall weight would be about the same and power would be greatly enhanced. A lot of work though for the average owner unless you are into this kind of a job. One thing nice though is if you change out the raer axle, you can go to the 10 inch wide rear brakes in place of the stock 7's. Oh, and you'll loose at least 2 miles to the gallon and 5 to 10 mph top speed. | ||
| RJ Long (Rjlong)
Registered Member Username: Rjlong Post Number: 1569 Registered: 12-2000 Posted From: 98.192.173.82 Rating: N/A |
Jim - 6-71T puts out the same as a 8V71N with N60 injectors - 275 hp and about 770 ft/lbs of torque. Roughly a hundred more than you're running now. Another thought: Keep the 4-spd and bolt in the 6-71T. You still won't win any drag races, but will have a lot more flexibility You might also bust the bevel gears with this - one of the reasons the transmission's AFTER the bevel gears in the 8V71-powered buses. FWIW & HTH. . . | ||
| Tim Hoskinson (Tdh37514151)
Registered Member Username: Tdh37514151 Post Number: 249 Registered: 9-2004 Posted From: 65.25.139.50  Rating: N/A |
There was a 4104 on e bay not long ago that had the in line 671 with a 730 auto. I am not sure what modifications were required to allow the longer engine trans combination to fit in the 96 inch width but I would think there would be a engine mounting and radiator reposition required. The rear end drive angle would also require changing of course. | ||
| Tom Christman (Tchristman)
Registered Member Username: Tchristman Post Number: 96 Registered: 1-2006 Posted From: 66.218.33.156 Rating: N/A |
The manual trans on the 04 is rated at 1200lb/ft torque. I saw one 04 where the owner mounted the turbo above the transmission, and used the right engine door for the air to air intercooler. He was running 80 injectors that gave him 300hp and 900ft/lb torque. This will be your easiest conversion (as long as you want to keep the manual transmission). The easiest engine/transmission change will be to a 6V-92TA and V730-then, as stated earlier, you'll have a real hot rod. AMGeneral's are basically a redesigned D700. When AMGeneral came out with their new design, Flyer also adopted the design for their D800. This is the only transit bus I know that came as a V drive version with AMGeneral, and in a T drive with the Flyer versions. There is enough overhang in the rear where either power plant can be used-and with the engine cradle-would be an easy swap out. I was thinking of doing that with some of Santa Monica Bus lines MCI classics that have Series 50's with B400 transmissions. But now am concentrating on my truck conversion. Good Luck, TomC | ||
| RJ Long (Rjlong)
Registered Member Username: Rjlong Post Number: 1570 Registered: 12-2000 Posted From: 98.192.173.82 Rating: N/A |
Tom - The Spicer in the '04 may be rated at 1200 ft/lbs, but I don't think the bevel gears are. As I have mentioned before, prior to the introduction of the 8V71, the V-drive manual gearboxes had the bevel gears mounted AFTER the transmission. GM found, during development work, that the higher torque output of the 8V was breaking the bevel gears, not the transmissions. That's why they swapped the bevel gears and transmissions in all the later production stick shift powertrains. Thus: Prior to the 8V71 intro, the manual layout was engine, clutch, transmission, bevel gears, rear axle. 8V71 & later layout is engine, clutch, bevel gears, transmission, rear axle. This only applies to the manual gearboxes. Automatics are set up engine, bevel gears, torque converter, transmission, rear axle. FWIW & HTH. . . | ||
| Tom Christman (Tchristman)
Registered Member Username: Tchristman Post Number: 97 Registered: 1-2006 Posted From: 66.218.33.156 Rating: N/A |
Verrry Interesting, RJ! |