I wonder if the Perkins "152" three cyl diesel is direct or indirect injection?
My Massey 203 with this engine has some sort of flame injection on the intake manifold. It never has worked yet she will fire off if its above freezing.
I don't think its ever been rebuilt since 1965 so, I question the compression.

BTW, that Cummins intake heater draws some serious current. I can see the voltmeter dip down to 9-10 volts when the engine is started but the heater is still cycling. Alternator can't keep up.

Also, my old VW 1.6NA has a injection advance knob that has to be pulled when its cold started.

Of all the diesels I own(ed) the cummins 5.9 will start no mater how cold it's been. MB 617 is next followed by the VW then the lazy Perkins.

Then explain why racers and performance enthusiasts will increase the size if the bore and use a "stroker" crank to increase the compression ratio and therefore boost horsepower? Because the increase in length of the stroke, for one, increases the compression ratio by increasing volumetric displacement within the cylinder. The shape of the heads do make a difference. Chryslers "A" engine series wedge chamber heads, for example! You answered your own question, if you read it. The compression ratio is the volume between BDC and TDC. A longer stroke simply provides more volume. Yes!! And an increase of compression ratio! One of the first things we did at Chrysler in the 1970's to comply with emissions was to shorten the stroke to LOWER the compression ratio. :book:

That's easy to explain.

A "racer" will take an existing engine, with a fixed displacement in the head, and increse the stroke. When that occurs, the volume of the cylinder increases, but the head remains the same.

Naturally, the compression ratio increases.

The discussion was limited to production engines and the question was whether a longer stroke increased the compression ratio. The only way this is true is if the stroke is increased with all other variables remaining identical. Naturally, an engine manufacturer wouldn't be so stupid to do such a thing.

The reason I brought up the whole stroke issue, was the relationship of stroke to the time it takes to compress the gas. On a long stroke engine, the time to compress increases hence allowing heat from the compression to dissipate into the block. With a large bore and short stroke, the time to compress would be shorter hence not allowing as much heat to dissipate perhaps increasing the engine's ability to start in cold temperatures.

It's an interesting theory, but, there is no difference in time for the short stroke and long stroke engines. The time it takes for the piston to rise within the bore of a long stroke engine is identical to the time it takes for the piston to rise in a short stroke engine.

The piston must travel faster in the long stroke engine to get to the destination at the same moment.

The only way to shorten the time is to increase the crank speed...........a very successful option if the technology is available.

I agree. So what I was thinking was that short stroked engines were spinning faster.

I have worked on a few stroker drag engines. The point generally that the racers are going for with increasing stroke is simply more cubic inches. In gassers increasing compression is not always advantageous so stroking is sometimes combined with increasing the size of the combustion chambers to keep the same compression ratio.

Long stroke engines generally produce more torque which should be obvious if you consider that the lever "arm" is longer with a longer stroke. The problem with long stroke is that the piston speed increases. At some point the acceleration and deceleration of the piston becomes too severe and the connecting rod will fail.

RT

Which is why we only stroked factory engines to a certain point while I was at Chrysler. Heavy duty engines like the 318/1/2/3 were stroked versions of the passenger car motors, but with heavier castings in the inside workings. Such as crank, Camshaft, connecting rods, etc. 440's were also stroked and no one at Chrysler thought this was stupid! We thought this a reasonably cost effective way to BURN RUBBER AND LIGHT THE ASPHALT!!!! It doesn't take much of a stroke to increase your compression ratio from, lets say 8.5:1 to 10:1 on gassers. We decreased the stroke when the fuel octane requirements in the 1970's as well as emission specs went into effect. If you increase the stroke and change nothing else, you get an increase in compression ratio! It's good for a maximum 1.5 increase in gassers! And if it's a Mopar, the engines will take it. If your a GM, trial and error, cylinder walls were pretty thin. If your a Ford, good luck and write when you get there. At Chrysler, we used some of the toughest metals including Nickel to make the strongest Muscle car blocks ever made! We wern't stupid for doing so, we were making you eat the dust when we passed you!:book: :D

Sorry, I don't buy it. I know a bit about Mother Mopar and her children. Bore and stroke as pretty constant within each engine family and the various displacements. The difference was smog heads, low compression through larger combustion chambers not destroking. Mopar blocks are generally pretty strong but the factory heads with a few notable exceptions flow like crap. It take a good head porting guy or aftermarket heads to make them run decent. RT

The reason that nobody thought it was stupid is that the change of stroke was not the only change made to the engine.

If you design an engine so that the piston reaches the deck and calculate the resulting volume of the head, you'll find that you'll need to redesign the piston and other components to allow a longer stroke with the same engine block.

So, as previously explained, when a manufacturer makes a change in stroke, he does so with the capability to change other components in the engine to accommodate the additional stroke.

Furthermore, if you change the stroke of a 318 for example, you won't have a "318" when you're finished. You'll have a different engine with a different designation. All small block 318, 340, 273, and 3.9L engines had a stroke of 3.31. The only larger stroke offered in the small block was 3.58" in the 360 engine. This was not a "stroked" version of the 318. It was a completely different engine.

So, your information is not quite correct.........again.

I was an engineer there for 16 years and when you have enough room by design, to make changes in compression ratio easily and without have to retool at additional cost, because your piston deck height has more room for length for instance, you can get a increase in compression ratio with NO other changes!! This wasn't Ford or GM and you assumption is INCORRECT AGAIN!! A 318/1/2 or /3 is a TOTALLY different animal that was offered as an option for Motorhomes, Marine motors and the guy who loved to tinker and not the car lot buyer! Technically yes, the stroked 318, 340, 383, 400, 413. 440 cubic inch size does change, however we left good enough alone because anyone who knows what their doing with a wrench and not just a college degree were some of our best enthusiasts! If you worked for Chrysler, we could have never invented the streetable HEMI! Yeah, it's got a HEMI! If you know anything about the History of Chrysler, our engineers were told to make happen what couldn't be done and we did it! Making a 400 for instance where the piston did NOT reach full deck height was a California engine smogged. ("M" code engine). Increase the piston travel a little more and you have some more horsepower in emission areas a little less strict ("N" code engine). piston travel to the top and you have a special performance "U" code engine. M series engines had 170 horse. N code engines had 215 horse. U code engines had 245 horse. Closed chamber head engines (yes some head changes here) of the same size but with Maltese heads had 285 Horse. Put on a 1000 CFM Thermoquad and Ram Horm exhaust and you bumped up tp 315 horses in the SAME 400!!!! Like my 1978 Special Edition Cordoba which was equipped with a 400"U" 1000 CFM Thermoquad, Ram Horn dual exhaust and T top. GET IT NOW????:dizzy2: P.S. It's not always in the book! Don't you think there was a reason we said "specs in your owners manual or underhood sticker must be used instead if they dissagree with the service manual"!

It was your claim that there are small block Chrysler engines that were "stroked" to gain additional compression.

I explained to you that all small block engines from the 273 to the 3.9 V6 all had the exact same stroke of 3.31".

Just to get you back on the topic, I'm still awaiting an answer for exactly where the production small block engines exist that have a stroke longer than 3.31".

After you produce this evidence, you can continue on with your compression discussions..........which were never disputed in the first place.

Why don't the 318 or 440's have glowplugs?

Because they are inferior gasoline burning engines that rely on a tiny little spark to inefficiently ignite their fuel.

Oh, gee, I'm so glad I've got your permission! Go find a 318/3 and PULL IT APART! If it has a Fleur de les stamped into the crank at the counter balacing weight of cylinder #5, then you will need to order the addendum for the specs for this engine. It was not a standard production model! Most of these were in the 1960's, but the 400's in particular, made it into the 1970's with the 440! The reason it WASN'T in the books is because we were NOT supposed to be advertising this during the liberal tree hugging 1970's! The Book listed these engines the same, but we couldn't tell you that your 318/1 or /3 was actually a 331, OK? It was a way of bending the rules after 1971 without breaking the law! If you don't believe me, try going to a wrecking yard for motorhomes and TRY to find a 318/3 (331)! If you want links, there are NONE! If you find a Cordoba from 1977 and 1978 with a "U" code engine, it will show up as a 400 in the Books, it will say 400 in the underhood sticker and it will be listed as a 400 in the vin#, but if you pull it apart and the crank is marked with a pair of XX's in a certain spot on the crank, technically you have a 409! We appeared to be "good" by not publicising this! Oh Brother. Go find a Mopar entusiast near you and learn something! Oh, 1972 through 1978 318's with a maltese cross at cylinder #7 in the casting are not in the book either! These were closed or wedge chamber high performance heads. (Psssst. Most of these will be missing too!) There were strict legal requirements about altering and modifying engines in the 1970's. As far as the Government was concerned, no one was going to tell them they didn't know what they were talking about either! The mess of the 1970's was what happens when our government (IDIOTS) told us how we are supposed to make cars! And we could make a few at random. When you bought a new car and if you looked closely at your ORDER form, there would be a little box next to letters you could barely read that would say something like "performance group". Your salesman could tell you what you were getting that wouldn't be listed in the specs. We could sell these parts, but were not allowed to have a row of them in the car lot. You could tell your salesman what you wanted and he would call the factory, but if the general public didn't ask, you don't offer. Does any of this help or make sense? The only ones not doing this was GM and Ford. Your not going to find proof in general print, you have to know what to look for and special order the amendment for specs.;) This was CHrysler! We dared to think for ourselves!:P