MY1PATH
Member
Hi folks, I've been working on Nissans for over 15 years I've built several engines, bumpers and other things along the way and it's been good fun but I've never touched a diesel Nissan and that is about to change. I recently bought a BMD21 4-door off Japanese auction and I'm looking forward to its arrival. I wanted a 4 door pickup to mod and play with and while there are plenty of 4-door d22's over here, I love the body style of the d21 chassis so that's what it had to be.
If I keep the diesel engine I'll probably intercool and put a more efficient turbo on it BUT I wish it was a manual... I'll tackle that if I find I am dissatisfied by the boring Auto (everything I own is manual). A buddy of mine insists the TD27 is better with an auto for keeping the RPM's down and having ratio's better suited to the earlier torque band.. I think I understand the TD will go 22-2500 all day but above that strays from the torque and wastes gas?
I went over to Gear Ratio Calculator and ran some numbers:
(assuming it has 4.6 gears already and I slap on some 235/85r16 tires)
4.6 AT 2500rpm I'd be going 75mph/120kph which is a very common speed over here (often pushed to 80-85)
4.6 MT 2500rpm limits me to 65mph/140kph BUT I have a set of 3.7 gears here...
3.7 MT 2400rpm would get me 75mph/120kph, 25-2700rpm if I run 80-85mph 129-137kph
3.7 AT 2000rpm to go 75mph, 2300rpm to go 85mph, 2500 RPM to go 90+...
I don't see myself going 90+ for long periods of time but I may touch it from time to time. Seems to me that 3.7 and MT targets my highway speeds good enough. The gears get closer together as you go up while the AT is a little bit more linear until you hit OD which is a bigger step.
Of course the challenge would be getting a TD27 Bell housing shipped to USA for my one of my spare FR5r30a transmissions or fabbing a Bell housing adapter. Can you tell I love manual transmissions?

If I keep the diesel engine I'll probably intercool and put a more efficient turbo on it BUT I wish it was a manual... I'll tackle that if I find I am dissatisfied by the boring Auto (everything I own is manual). A buddy of mine insists the TD27 is better with an auto for keeping the RPM's down and having ratio's better suited to the earlier torque band.. I think I understand the TD will go 22-2500 all day but above that strays from the torque and wastes gas?
I went over to Gear Ratio Calculator and ran some numbers:
(assuming it has 4.6 gears already and I slap on some 235/85r16 tires)
4.6 AT 2500rpm I'd be going 75mph/120kph which is a very common speed over here (often pushed to 80-85)
4.6 MT 2500rpm limits me to 65mph/140kph BUT I have a set of 3.7 gears here...
3.7 MT 2400rpm would get me 75mph/120kph, 25-2700rpm if I run 80-85mph 129-137kph
3.7 AT 2000rpm to go 75mph, 2300rpm to go 85mph, 2500 RPM to go 90+...
I don't see myself going 90+ for long periods of time but I may touch it from time to time. Seems to me that 3.7 and MT targets my highway speeds good enough. The gears get closer together as you go up while the AT is a little bit more linear until you hit OD which is a bigger step.
Of course the challenge would be getting a TD27 Bell housing shipped to USA for my one of my spare FR5r30a transmissions or fabbing a Bell housing adapter. Can you tell I love manual transmissions?

If I don't keep the diesel there's a new 280hp supercharged v6 from a D22 complete with rebuilt 4x4 manual transmission sitting in my garage It was gonna go in one of my pathfinder (terrano) before I decided to buy a pickup to replace it. But I gotta drive it before I decide... Until then, I play the waiting and overthinking game.If I keep the diesel engine
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