I know there's a thread about 1HDFT vs 1HDFTE, but I'd like to focus more specifically on 1HDT vs 1HDFT as for a basic Aussie 80 series owner they are the most common engine choices for diesel upgrades. Many 1hz 80's still exist (like mine) with the original ex-factory motor. Standard upgrade path is to get a 1hdt, but 1hdft is another valid pathway.
There are hardly any people fitting other diesels to their 80's but some do.
So what technical reasons should one consider a 1hdt vs a 1hdft? Does the 1hdt have 'design flaws'? Obviously 1hdft is 24 valve vs 1hdt being 12 valve. For a DD vehicle like mine that rarely tows big loads and doesn't so much off road, and is already 30+ years old, is there any cost-effectiveness in opting for a 1hdft instead of 1hdt?
For normal use, is it of any relevance that the power curve of a 1hdft is supposedly better at higher rpm compared to that of a 1hdt (which is basically a 1hz block with a different head and air intake design I think)?
Cost-wise, a jap import 1hdt is around $10k and a 1hdft can be up to $15k. Aussie dollar prices.
I'm not sure I'd want to get the existing 1hz rebuilt and carry on as it's too old/worn to make a good candidate to fit a turbo kit onto. If I can find a good diesel motor place I will ask about potential cost range for a full rebuild.
In hindsight it probably won't matter which engine option I go for (even 1hz + t) - cost is still going to be upward of $10k and that's 2/3 of the insured value, but I'm not in a position to justify selling my 80 to get another one, so engine swap seems the only valid way to deal with the old motor.
There are hardly any people fitting other diesels to their 80's but some do.
So what technical reasons should one consider a 1hdt vs a 1hdft? Does the 1hdt have 'design flaws'? Obviously 1hdft is 24 valve vs 1hdt being 12 valve. For a DD vehicle like mine that rarely tows big loads and doesn't so much off road, and is already 30+ years old, is there any cost-effectiveness in opting for a 1hdft instead of 1hdt?
For normal use, is it of any relevance that the power curve of a 1hdft is supposedly better at higher rpm compared to that of a 1hdt (which is basically a 1hz block with a different head and air intake design I think)?
Cost-wise, a jap import 1hdt is around $10k and a 1hdft can be up to $15k. Aussie dollar prices.
I'm not sure I'd want to get the existing 1hz rebuilt and carry on as it's too old/worn to make a good candidate to fit a turbo kit onto. If I can find a good diesel motor place I will ask about potential cost range for a full rebuild.
In hindsight it probably won't matter which engine option I go for (even 1hz + t) - cost is still going to be upward of $10k and that's 2/3 of the insured value, but I'm not in a position to justify selling my 80 to get another one, so engine swap seems the only valid way to deal with the old motor.
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