I dont mean to come off hateful and my apologies in advance for being so blunt but, it sounds like you read a lot of info on various online forums and try to make decisions based on other peoples opinions. The problem is everyone has an opinion and at a certain point the opinions get further and further from the facts. It's time for a reality check. You should speak to someone with actual hands on experience with the engines you're interested in.
For instance, installing a 6bt in a 70 series or even more so a 5bt like you mentioned just isn't going to happen. I'm not familiar with this 5bt but, the 6bt is too large and if a 5bt is taller than you can forget it without cannibalizing that truck beyond recognition.
"Freon in an intercooler"? what is this "double squeeze turbo" you keep mentioning and where do you come up with these ideas? I've never heard this term before, is it referencing some sort of compound turbo set up? What are your intended purposes for this truck? Do you plan on doing some sort of mud racing with it? These modifications don't seem realistic and very extreme unless you are doing some sort of racing. If not, there is no need for compound turbo chargers. Most of the engines mentioned (12ht, 15bft, 13bt etc are capable of propelling the truck quiet comfortably at todays speed limits with the exception of the 3b turbo. What is your skill level at fabrication or what is your budget? Do you plan on doing this work yourself or paying someone to do it? I don't know what info you based your decision on that a 12ht has more torque than a 15bft for instance? The larger factor to consider is that the 15bft will bolt into your existing chassis mounts and the 12ht will require a heck of a lot more fabrication and a new transmission. I believe the parts supply for a 15bft is much better than for a 12ht. Yes there are ton of 12ht builds in AU and they are much more common there but parts like rockers, shafts, cams, etc are wear items that cant be purchased new anymore.
Also the things you read about a 3b cracking heads at 20 lbs of boost is B.S. like alot of the other stuff you are reading. The boost doesn't crack the heads the heat does which generally comes from over fueling. The engine cant shed the heat which it was never designed to make once the additional fuel is added. It is not so much an issue of coolant capacity or temp but problem of airflow and ability for the cylinder head to shed the heat from the precups.
salty coconuts mentioned a 15bfte....I would steer clear of the electronic controlled version of any of the Toyota engines unless you want to spend more money and time on the electrical portion of your conversion than the conversion itself.
For instance, installing a 6bt in a 70 series or even more so a 5bt like you mentioned just isn't going to happen. I'm not familiar with this 5bt but, the 6bt is too large and if a 5bt is taller than you can forget it without cannibalizing that truck beyond recognition.
"Freon in an intercooler"? what is this "double squeeze turbo" you keep mentioning and where do you come up with these ideas? I've never heard this term before, is it referencing some sort of compound turbo set up? What are your intended purposes for this truck? Do you plan on doing some sort of mud racing with it? These modifications don't seem realistic and very extreme unless you are doing some sort of racing. If not, there is no need for compound turbo chargers. Most of the engines mentioned (12ht, 15bft, 13bt etc are capable of propelling the truck quiet comfortably at todays speed limits with the exception of the 3b turbo. What is your skill level at fabrication or what is your budget? Do you plan on doing this work yourself or paying someone to do it? I don't know what info you based your decision on that a 12ht has more torque than a 15bft for instance? The larger factor to consider is that the 15bft will bolt into your existing chassis mounts and the 12ht will require a heck of a lot more fabrication and a new transmission. I believe the parts supply for a 15bft is much better than for a 12ht. Yes there are ton of 12ht builds in AU and they are much more common there but parts like rockers, shafts, cams, etc are wear items that cant be purchased new anymore.
Also the things you read about a 3b cracking heads at 20 lbs of boost is B.S. like alot of the other stuff you are reading. The boost doesn't crack the heads the heat does which generally comes from over fueling. The engine cant shed the heat which it was never designed to make once the additional fuel is added. It is not so much an issue of coolant capacity or temp but problem of airflow and ability for the cylinder head to shed the heat from the precups.
salty coconuts mentioned a 15bfte....I would steer clear of the electronic controlled version of any of the Toyota engines unless you want to spend more money and time on the electrical portion of your conversion than the conversion itself.
