looking at buying a 79 bj40 with the b engine. i have seen and read a lot about the 3b but not much on the the straight b. is it just as reliable as the 3b and is it as easy to mate up a turbo. whats the difference between the two engines. ie. can the straight b be turned into a 3b with some boring and head and swap? or is it a totally different block? any help would be sweet.
b vs 3b diesel engine
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Falco80
Burning dinosaur bones...
The B diesel is smaller capacity, at around 3.0L while the 3B is around 3.4L. The 3B has piston skirt oil jets and the B does not. Probably the main reason the 3B takes forced induction better. My B diesel is strong little engine, and while i too originally hunted for a 3B-powered cruiser, the B is still a fine choice.
Remember the B powered cruiser does not accelerate, it slowly gathers speed. So if you appreciate speed it's not the engine for you. If you appreciate simple, tractor-like reliability then it's great.
Remember the B powered cruiser does not accelerate, it slowly gathers speed. So if you appreciate speed it's not the engine for you. If you appreciate simple, tractor-like reliability then it's great.
crushers
post ho
i have owned both and like both ...
the 3B has a better record of reliability
the B is better on fuel
i wouldn't hessitate to own either.
history of the engine is more important than the engine size. well maintained is important to both. neglected and both engines will cost $$$$$ to fix
the 3B has a better record of reliability
the B is better on fuel
i wouldn't hessitate to own either.
history of the engine is more important than the engine size. well maintained is important to both. neglected and both engines will cost $$$$$ to fix
Falco80: "It slowly gathers speed" ....now that is truly funny and should be on the cover of the owners manual.
.....1978HJ45
.....1978HJ45
Crushers nailed it. The B engine take a turbo better due to the slightly higher compression (creating a larger benefit with lower boost). with the smaller displacement and the higher compression, they are also better on fuel.
The 3B is a larger displacement and lower compression engine an therefore will use more fuel. It handles a turbo better from a wear/heat standpoint due to the piston skirt cooling oil squirters and (If i remember correctly) a more beefy main bearing assembly.
If my 2B was in healthy condition, I'd keep it as it is GREAT with the turbo. It is essentially between the B and 3B in size and design.
It really comes to what you want. If you are a fuel conscious daily driver that wheels moderately, the B is a great choice. If you want to be harder on the engine and run higher boost and squeeze more performance out of the engine... a 3B is a great idea (or a swap to a 1HD-T/1HZ-T for example).
The 3B is a larger displacement and lower compression engine an therefore will use more fuel. It handles a turbo better from a wear/heat standpoint due to the piston skirt cooling oil squirters and (If i remember correctly) a more beefy main bearing assembly.
If my 2B was in healthy condition, I'd keep it as it is GREAT with the turbo. It is essentially between the B and 3B in size and design.
It really comes to what you want. If you are a fuel conscious daily driver that wheels moderately, the B is a great choice. If you want to be harder on the engine and run higher boost and squeeze more performance out of the engine... a 3B is a great idea (or a swap to a 1HD-T/1HZ-T for example).
It is but I'd recommend not boosting higher than 10 psi with it...
My 2B drives with more power than a 2F. Much more torque. A 10 PSI B should be similar. Maybe a bit less powerful. Make sure your cooling system is in top shape as that is what will kill the system.
crushers
post ho
it isn't the boost that will kill the engine, it will be your right foot.
pyrometer
boost gauge
oil pressure gauge at turbo inlet
pyrometer
boost gauge
oil pressure gauge at turbo inlet
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The B engine is a very sturdy, hearty engine. AXT makes a turbo kit for it. I would follow Crusher's admonition here exactly. Add the turbo and all of the monitoring guages, pyrometer, etc. Keep the boost to 10 psi or lower. The only complaint that I ever had with the little B was the need to get a running start to get up and over hills. The turbo will cure that issue for you. As you are doing that make sure that your cooling system is in top shape. Take good care of it. Baby it with preventive maintanance and it should serve you well for years to come. 
Turbo b engine
Installing a t 04 turbo on my76 cruiser with a b diesel.what is the max boost and how can I controll it the turbo has no waste gate or bleed off valve and will I need an intercooler .
Installing a t 04 turbo on my76 cruiser with a b diesel.what is the max boost and how can I controll it the turbo has no waste gate or bleed off valve and will I need an intercooler .
I am luckey enough to have a Mark II B engine, so I get piston cooling and a few other nice things. I rescued her from a dump rebuilt her and she has showed emence gratitude since . Rebuildable and depenable, but yes, the running start thing is somewhat true, You dont want diff's any lower than 4.5 ( non turbo). I want to turbo this baby at some stage, so watch this spot.
Enjoy either way.
Enjoy either way.
Slightly more than a kid on a skateboard LOL.
Actually I remember driving one brand new that belonged to my friend and I thought it was not bad at all.
No, I never did the turbo, but if yours is a mark II then the 14B Turbo manifold fits like a glove and you are already half way there.
bsweaty
SILVER Star
@Gengis thanks for the response after all this time. I have lots of questions. I’m familiar with L series motors, specifically the 2LT and 1KZTE and new to this motor.
Did you ever have any apprehension of turboing the B due to it being IDI? Thoughts on maybe modifying the precups(assuming the head has precups) for better injection? I’m weighing out the pros and cons of turboing my Dyna and the longevity of it. I would do new injectors, ARP studs, intercooler, and adjust the timing a few degrees. I’d likely keep boost under 10psi and keep an eye on EGTs. How does this approach sound to you?
Did you ever have any apprehension of turboing the B due to it being IDI? Thoughts on maybe modifying the precups(assuming the head has precups) for better injection? I’m weighing out the pros and cons of turboing my Dyna and the longevity of it. I would do new injectors, ARP studs, intercooler, and adjust the timing a few degrees. I’d likely keep boost under 10psi and keep an eye on EGTs. How does this approach sound to you?
Toyota themselves turbo a number of IDI engines so not to worry there. I would only replace head bolts if yours are TTY. the main thing about IDI with a turbo, and this comes up again and again, is the extra heat in the head, so an intercooler and perfectly running cooling system is a must. Vans, like yours have cool air flow restrictions and space constraints. So you have some work to do. Think of water to air intercoolers and get a nice shot of cool air to the intake ( snorkel). Do a search on turboing the HZ motor, which is also IDI. They do not seem to touch the pre-cups, and push heavily for intercoooling. Don't fret about the boost pressure if you watch the egt's properly.
It's heat ( cooling and EGT) that will kill your engine, not boost. Oh ,and your right foot.
It's heat ( cooling and EGT) that will kill your engine, not boost. Oh ,and your right foot.
bsweaty
SILVER Star
@Gengis makes a ton of sense. I have both a 2.4 2lte and a 3.0 1lzkte in my surfs at the moment. I am very familiar with the head heating issues. Seems like as long as we stick to the basics and get gauges set up to monitor, we should be good. Thanks for chiming in after all this time!
bsweaty
SILVER Star
Out of curiosity, where were you going to run your oil supply from?
