Boost Increase: Gasoline vs Diesel
04-30-2013, 08:13 PM
#16
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Never worked on a Ford so I can't comment on that. But I have seen other, older diesels that didn't have glow plugs but used manifold heating elements and would add excess fuel (to increase the dynamic compression) to get em to fire up. Timing would also change when cold starting.
04-30-2013, 10:09 PM
#17
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https://www.google.com/search?q=moro...ient=firefox-a
It's an old hot-rod trick for drag racing, they fill the block entirely so it's absolutely solid, and they can stress the hell out of the engine for monster power, but it only works for short races. Blown 944 has used the same stuff in his 944 block, but only filled it half way.
You can search for the threads, but here's the cliff's notes:
- the filler is made for iron blocks, but is claimed to work in aluminum as well
- blown 944 (Sid) has had good results
- the later 944/968 blocks had a shallower water area, essentially the floor was raised halfway up the outsides of the cylinders to support them better. Also, the cylinders got webbed together. If the 951s were made with these, they wouldn't blow head gaskets so often. The block filler mimics this.
The 944 block is half of the 928 block, and the 928 block was designed in the early to mid 70s, as the company's first 1-piece engine block, first water cooled engine, and not intended to be boosted. Just be happy they last as long as they do - it's a miracle.
Diesel fuel is less refined than gasoline. It is less combustible. It releases more energy per unit gasoline during combustion.
Glow plugs don't ignite fuel, all they do is warm up the combustion chamber to allow compression-ignition to happen when the engine is cold. New, tight diesel engines don't need glow plugs to start - even when they're cold they have good enough compression to cause ignition.
Diesel engines usually are easier to pump up because the engines are typically very robust, and they don't have the detonation problem. 951 engines blow HGs because they don't get tuned well enough (sometimes "well enough" is out of reach, for this old inefficient engine and modern wacky power goals) and the cylinders move.
It's an old hot-rod trick for drag racing, they fill the block entirely so it's absolutely solid, and they can stress the hell out of the engine for monster power, but it only works for short races. Blown 944 has used the same stuff in his 944 block, but only filled it half way.
You can search for the threads, but here's the cliff's notes:
- the filler is made for iron blocks, but is claimed to work in aluminum as well
- blown 944 (Sid) has had good results
- the later 944/968 blocks had a shallower water area, essentially the floor was raised halfway up the outsides of the cylinders to support them better. Also, the cylinders got webbed together. If the 951s were made with these, they wouldn't blow head gaskets so often. The block filler mimics this.
The 944 block is half of the 928 block, and the 928 block was designed in the early to mid 70s, as the company's first 1-piece engine block, first water cooled engine, and not intended to be boosted. Just be happy they last as long as they do - it's a miracle.
Diesel fuel is less refined than gasoline. It is less combustible. It releases more energy per unit gasoline during combustion.
Glow plugs don't ignite fuel, all they do is warm up the combustion chamber to allow compression-ignition to happen when the engine is cold. New, tight diesel engines don't need glow plugs to start - even when they're cold they have good enough compression to cause ignition.
Diesel engines usually are easier to pump up because the engines are typically very robust, and they don't have the detonation problem. 951 engines blow HGs because they don't get tuned well enough (sometimes "well enough" is out of reach, for this old inefficient engine and modern wacky power goals) and the cylinders move.
05-01-2013, 04:23 PM
#18
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What diesel engine are you referring to? Every diesel needs some type of a cold start mechanism. If it lacks glow plugs, it makes up for it with an intake air heater and/or running rich. Diesels without glow plugs don't work because they're "tighter", they start better because they crank faster. Look at the amperage draw and gear reduction specs, they have changed a lot over the years of diesels! The newer, D.I. diesels have much lower compression than the old mechanical types, so technically they are "looser" than the oldies.
05-02-2013, 04:22 AM
#19
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Hmm, interesting.
The one I was talking about is my friend's mid 2000s dodge ram cummins turbodiesel. The thing has pretty low miles, as he only uses it a few weeks per year. He can jump in and start it like it's a gasoline-powered car.
The one I was talking about is my friend's mid 2000s dodge ram cummins turbodiesel. The thing has pretty low miles, as he only uses it a few weeks per year. He can jump in and start it like it's a gasoline-powered car.
