So I have this Diamond T, a '67 with a 6-71N. Dunno if it's 2 or 4 valve, dunno what injectors it has.. Yet. It's just a toy. Thought I'd like yet another truck that turns diesel into beautiful noise.
Nobby you out there?
Nobby you out there?
The "N" designation means naturally aspirated, or only supercharged(no turbo). I've seen turbo'd in both 2 and 4 valve, but the 4 valve is capable of ALOT more power. I believe it was N-95's were about as big of an injector you can go without a turbo, and will put you in the low 300HP range if it's a 4 valve. If it's a 2 valve it will be quite a bit lower. You will also need the better 4 valve head to reach that HP number as there are several different heads out there for them. Friend of mine just basically gave away a brand new 4 valve 6-71 turbo head(one of the GOOD ones). He needed money, and the shop he took it to only offered him $350 for it after he had a receipt showing he had bought it 2 years before for $1100.Oh yeah, the n designation is the 'newer' 4 valve. Most parts don't interchange different piston, rods, "n"needle injectors, more but cant remember. They love high rpm, so well balanced components make a difference. I worked on them, but def not an expert. Ahh, the magic of a blown-natural aspiration.
I wonder if fluid damper makes a balancer for them? The unbalanced shake was an unmistakable drawback. They are mega oil leakers thatcreated the name leaktroit. all that air blown through its no wonder. I always wanted to hook up a vacuum system to the crankcase to see how much of that it would cure. Maybe a gapless ring in #2 position could help that also? Definitely spend time on a good felt job fitment in the blower, that helps a lot.
My uncle has a pair of JOHNSON & TOWERS 6-71N's at 310HP in his boat. I went through the factory service manuals and there were about 4 different 4 valve cams, 3 heads, and who knows how many injectors. DETROIT used the last letter to designate teh aspiration system. N was natural or just supercharged(2 stroke diesels have to have a supercharger to run), T was for turbo, TT for twin turbo, TA for turbocharged aftercooled, and a few other designations. The REALLY high HP ones had quite a bit of technology in them for there day. They used a smaller port system to improve bottem end pull, but had a supercharger bypass valve that opened once teh turbos had enough boost to take over and bypassed the superchargers all together. If it is a 4 valve N engine, it can be one of about 3 variants IIRC. The base model low output, high output natural engine, or the turbo engine without a turbo. Most of the turbo engines without turbos went to companies like JOHNSON & TOWERS for marine conversions. For trucks most got the low output generator engine version(with a different governor system than the generator version).Oops, sorry if I misled you. I thought the n was for the needle injector change design when they went to the 4 valve, I remember reading about it but then again I have a hard time remembering what I remember.
I know the only change we would make when adding the turbo parts wise was the injectors, turbo and all the duct work. It was a kit so idk if the internals of the turbo was set up the same to run as hard as factory turbo or not. Nothing internal was changed. Don't miss my Daily Dose of Detroit. Once in a great while is fine with me anymore. Do keep us updated tho...
You can get it with a big turbo and injectors, I am way to far out to know the numbers but 2 years ago I helped a friend drop in a 170 hp or so new one, but he was like 10,000 into it iirc.for a complete assembly. You needing turbo kit complete is probably in the range of $3000 would be my guess. Nothing high on skill level, just time and knuckle skin.I have less than 1000 hrs on the 4-53, it is in prime shape.
It'll fire up in a couple seconds without start fluid after sitting still 9 months out of the year.
I like to get 25-30 more ponies out of it so the SOB will pull my 567 baler without losing up to 500 RPM depending on the slope.