Prechamber Mod "Flame" Front
Prechamber Mod "Flame" Front
Well the damage is done, I'll make a new tool later but for the time being I gotta figure out how to get the old damaged collars out. I'm gonna try a chisel first , then go try find the right threads and weld in a bolt , I don't have any spare injectors to use.. does anyone know what the coarse threads are for the collar
(06-05-2013, 07:25 PM)poleshady Well the damage is done, I'll make a new tool later but for the time being I gotta figure out how to get the old damaged collars out. I'm gonna try a chisel first , then go try find the right threads and weld in a bolt , I don't have any spare injectors to use.. does anyone know what the coarse threads are for the collar
(06-05-2013, 07:25 PM)poleshady Well the damage is done, I'll make a new tool later but for the time being I gotta figure out how to get the old damaged collars out. I'm gonna try a chisel first , then go try find the right threads and weld in a bolt , I don't have any spare injectors to use.. does anyone know what the coarse threads are for the collar
thanks ill call around and try to find a bolt like that.
i got 3 pre chambers out, one is stuck in there, so its soaking with some penetrating oil tonight.
here is one of the ones i pulled, is this in good shape?
and ill start looking for some reamers tomorrow. did you open up the rear two smaller holes also? but left the bottom hole alone right?
From the pic it looks ok, but check the bar in the center of the chamber and be sure it is tight.
Personally I drill out all the holes but the bottom one as you mentioned, that is drain hole. You will get lots of different recommendations here as some will say only do the big three holes, some say do them all, and some say don't do any of them lol
I know, old thread, but I came across this patent filed in 2001 and thought I'd share it since it has to do with the subject.
The same guy has some other very interesting patents on behalf of Chrysler about insulating the prechambers. Worth a read.
http://www.patentbuddy.com/Patent/6065441
I have to add, could be wrong here, but if anyone has ever paid attention to the carbon buildup on the piston in relation to pc holes, it seems pretty clear that the different diameters are there to control the pressure expansion in relation to the pc's location in the combustion chamber. As it is off center in the cylinder, the holes get progressively larger relative to distance from the cylinder walls. Look at the score marks. Smallest at the points where the prechamber is closest to the wall. Makes sense, consider how you'd like a pressure wave to behave in an environment where it originates off center, yet uniform expansion is desirable. Want all that extra pressure bouncing of cylinder walls and hammering down on one side of the piston significantly more than the other? Maybe splitting hairs here, but assuming we've more or less accepted that more pc flow is desirable, stands to reason that ideally you'd like to introduce more holes on a spacing and sizing gradient consistent with the existing trends and conically port them on a very slight negative axis (10-15 degrees?). Nice even expansion that way with the added bonus of a little extra downward encouragement. I'd imagine a decent egt drop over just increasing bore because of the theoretical possibility of less work being wasted and mayyyybe even some more love on the low end. I've got my 617a torn up for a rebuild, heads currently on my coffee table(yeehaw) receiving a fairly aggressive port/polish job, and, along with other goodies , I'm gonna go ahead and screw up my pc's while I'm at it. Granted, I have no intention on a dyno run unless both free and unrealistically convenient, who cares lol, but some loud obnoxious videos are guaranteed. Also though, I'd be curious to the idea of adding significantly smaller holes between the others and maybe even a little bit closer to the tip creating something of a "crown" pattern, again sized in gradient but tiny, in an attempt to create a pressure wave that is more centrally energetic/downwardly cuncussive without getting too crazy over the latter one that distributes energy, ideally, pretty much uniformly. Hopefully I get an eyebrow or two lifted with this.
Just to clarify, I noted on every piston head that the carbon buildup was very heavily concentrated in areas where the prechamber was closest to the cylinder wall, and especially in the areas around the smallest prechamber holes exhaust and were subject to the most turbulence. Now, in a perfect world one would think that a properly distributed combustion event would be unlikely to leave consistently localized deposits.
Juuuuust sayin...
So after a long period, I started working on the engine again, Anyone now the torque or angle to set the prechamber retainer ring? i've read at peachpart is was 130nm but it was the only source I could find an I want to be sure it's correctly tightnent. Multiple shop manuals don't show the prechamber, only headgaskets, glowplugs etc.
(08-30-2015, 08:49 AM)barrote hi,
2 valve engines 100 for vertical injector, 130 for inclined injector , 4 valve 130.
(08-30-2015, 08:49 AM)barrote hi,
2 valve engines 100 for vertical injector, 130 for inclined injector , 4 valve 130.
Have run My hogged out Pre-Chambers for over a year. Pulled head today and pistons look great even though the bottom hole is also drilled.
Problem is head is cracked Cylinders 2, 3, and 4 ....
(11-24-2015, 04:06 AM)Captain America Have run My hogged out Pre-Chambers for over a year. Pulled head today and pistons look great even though the bottom hole is also drilled.
Problem is head is cracked Cylinders 2, 3, and 4 ....
(11-24-2015, 04:06 AM)Captain America Have run My hogged out Pre-Chambers for over a year. Pulled head today and pistons look great even though the bottom hole is also drilled.
Problem is head is cracked Cylinders 2, 3, and 4 ....
(11-24-2015, 02:09 PM)PanicButton(11-24-2015, 04:06 AM)Captain America Have run My hogged out Pre-Chambers for over a year. Pulled head today and pistons look great even though the bottom hole is also drilled.
Problem is head is cracked Cylinders 2, 3, and 4 ....
Hey captain, seeing as you are one of the forerunnerswith all this, just wondering if you could post some pics of that damage and your pistons. Just curious to see if there's any pattern that makes my head start to itch..
(11-24-2015, 02:09 PM)PanicButton(11-24-2015, 04:06 AM)Captain America Have run My hogged out Pre-Chambers for over a year. Pulled head today and pistons look great even though the bottom hole is also drilled.
Problem is head is cracked Cylinders 2, 3, and 4 ....
Hey captain, seeing as you are one of the forerunnerswith all this, just wondering if you could post some pics of that damage and your pistons. Just curious to see if there's any pattern that makes my head start to itch..
Here is the cracked head cyl 2, 3, 4, ( I dont think the Pre-Chambers had anything to do with this)
And now the pistons
This is only after wiping them with a rag
Number 5 I did not wipe just to show what it looked like when I pulled the head off
Maybe the PC's didn't have anything to do with it. However, your PC's are the most hogged out ones I've ever seen and now a cylinder head not known for cracking has cracked in multiple cylinders. It should be considered a data point. Thank's for sharing the info.
I'm assuming your cooling system was working fine, right? No overheating, etc...
(11-25-2015, 06:31 AM)hooblah Isn't head cracking a common problem with 603's?
(11-25-2015, 06:31 AM)hooblah Isn't head cracking a common problem with 603's?
(11-25-2015, 09:01 AM)raysorenson Maybe the PC's didn't have anything to do with it. However, your PC's are the most hogged out ones I've ever seen and now a cylinder head not known for cracking has cracked in multiple cylinders. It should be considered a data point. Thank's for sharing the info.
I'm assuming your cooling system was working fine, right? No overheating, etc...
(11-25-2015, 09:01 AM)raysorenson Maybe the PC's didn't have anything to do with it. However, your PC's are the most hogged out ones I've ever seen and now a cylinder head not known for cracking has cracked in multiple cylinders. It should be considered a data point. Thank's for sharing the info.
I'm assuming your cooling system was working fine, right? No overheating, etc...
(11-24-2015, 04:06 AM)Captain America Have run My hogged out Pre-Chambers for over a year. Pulled head today and pistons look great even though the bottom hole is also drilled.
Problem is head is cracked Cylinders 2, 3, and 4 ....
(11-24-2015, 04:06 AM)Captain America Have run My hogged out Pre-Chambers for over a year. Pulled head today and pistons look great even though the bottom hole is also drilled.
Problem is head is cracked Cylinders 2, 3, and 4 ....
(11-25-2015, 11:42 AM)MTUPower How big did you enlarge the holes to? How temps have you seen on your EGT? For how long? How much fuel are you putting in? Which all leads to - why do you think your head has cracks? ...and lastly- if the engine is running fine are you going to reinstall the head or a buy a new one?
(11-25-2015, 11:42 AM)MTUPower How big did you enlarge the holes to? How temps have you seen on your EGT? For how long? How much fuel are you putting in? Which all leads to - why do you think your head has cracks? ...and lastly- if the engine is running fine are you going to reinstall the head or a buy a new one?
I might add that when the engine got hot those few times I was under full boost high rpm for too long lol either going through mud or in the sand. Full load on the engine while pushing hot water out
That brings to question in my mind, was your cooling system working correctly? Unless you were hogging on it for 10 minutes straight, I figured the cooling system would be adequate.
Is your A/w intercooler plumbed seperate or into the cooling system?
sorry to interrupt , but cracks does not have to do with vibes....
those holes in the precup are too wide, they are not consistente with what people is doing in here (europe) usually we d open them 25% max , my experience is in 4 valve engines and usually what works best is diff hole size , with out never exceed the 25% the botom hole stays 1.75 and the others u have them in the 25% band, i used 2.50 and 3.00 mm the only thing i gain from using the 3.0mm was noise and vibes.
my head is still toguether but i would bet vibes are killing the head.
good luck with it.
(11-25-2015, 05:08 PM)barrote sorry to interrupt , but cracks does not have to do with vibes....
those holes in the precup are too wide, they are not consistente with what people is doing in here (europe) usually we d open them 25% max , my experience is in 4 valve engines and usually what works best is diff hole size , with out never exceed the 25% the botom hole stays 1.75 and the others u have them in the 25% band, i used 2.50 and 3.00 mm the only thing i gain from using the 3.0mm was noise and vibes.
my head is still toguether but i would bet vibes are killing the head.
good luck with it.
(11-25-2015, 05:08 PM)barrote sorry to interrupt , but cracks does not have to do with vibes....
those holes in the precup are too wide, they are not consistente with what people is doing in here (europe) usually we d open them 25% max , my experience is in 4 valve engines and usually what works best is diff hole size , with out never exceed the 25% the botom hole stays 1.75 and the others u have them in the 25% band, i used 2.50 and 3.00 mm the only thing i gain from using the 3.0mm was noise and vibes.
my head is still toguether but i would bet vibes are killing the head.
good luck with it.
(11-25-2015, 01:11 PM)MFSuper90 That brings to question in my mind, was your cooling system working correctly? Unless you were hogging on it for 10 minutes straight, I figured the cooling system would be adequate.
Is your A/w intercooler plumbed seperate or into the cooling system?
(11-25-2015, 01:11 PM)MFSuper90 That brings to question in my mind, was your cooling system working correctly? Unless you were hogging on it for 10 minutes straight, I figured the cooling system would be adequate.
Is your A/w intercooler plumbed seperate or into the cooling system?
(11-25-2015, 05:08 PM)barrote sorry to interrupt , but cracks does not have to do with vibes....
those holes in the precup are too wide, they are not consistente with what people is doing in here (europe) usually we d open them 25% max , my experience is in 4 valve engines and usually what works best is diff hole size , with out never exceed the 25% the botom hole stays 1.75 and the others u have them in the 25% band, i used 2.50 and 3.00 mm the only thing i gain from using the 3.0mm was noise and vibes.
my head is still toguether but i would bet vibes are killing the head.
good luck with it.
(11-25-2015, 05:08 PM)barrote sorry to interrupt , but cracks does not have to do with vibes....
those holes in the precup are too wide, they are not consistente with what people is doing in here (europe) usually we d open them 25% max , my experience is in 4 valve engines and usually what works best is diff hole size , with out never exceed the 25% the botom hole stays 1.75 and the others u have them in the 25% band, i used 2.50 and 3.00 mm the only thing i gain from using the 3.0mm was noise and vibes.
my head is still toguether but i would bet vibes are killing the head.
good luck with it.
(11-26-2015, 12:29 PM)OM616 LOL... Then you really wont like what I am doing with my PCs lol...... I am going to machine a slot along all three front holes making a mouth so to speak.![]()
I did not know we her in the USA had to be consistent "with what people is doing in here (europe)"![]()
All in good fun, but races are not won by staying consistent with the competition lol..
(11-26-2015, 12:29 PM)OM616 LOL... Then you really wont like what I am doing with my PCs lol...... I am going to machine a slot along all three front holes making a mouth so to speak.![]()
I did not know we her in the USA had to be consistent "with what people is doing in here (europe)"![]()
All in good fun, but races are not won by staying consistent with the competition lol..
[/quote]
LOL... Then you really wont like what I am doing with my PCs lol...... I am going to machine a slot along all three front holes making a mouth so to speak.
I did not know we her in the USA had to be consistent "with what people is doing in here (europe)"
All in good fun, but races are not won by staying consistent with the competition lol..
[/quote]
hehe hhehe , i didn´t say that u´re walking the wrong road!!!! i was trying to say that u´re technic with the precups are far diff from what i experienced and what the fins/swedish/ germans and me portuguese do... i can explain the main idea behind my line of thought....
i tryed big holes , gained nothing remarkable (150cc pump) the remarkable gains were when i moved from stock 8x2.25 to 8x2.50.
i friend of mine has a W460 with the 617A i made a 120cc pump for him and we didn´t change the precups and the thing F$%#" rocks.
before i was fond of big holes thats why i tryied 3mm ones , and the only gain was noise , and ratle in idle, so i wonder .... the 8x the área of the 8 holes is far more than the neck área wich is 7mm. its not even necessary to use maths to see that.
if we take a look at the law´s ruling the flow in a section we can determine that being the exit área bigger than the section behind the velocity of the gas does not increase but it does decelerate wich causes increase in pressure , giving a false idea of improved performance.
it is my understanding that best way to go would be cutting the neck from 7mm to say 9mm and leave some of the holes alone , and increase the others but keeping the exit área 20 to 30% below the neck área , the idea is to gain velocity in the gas leaving the precup.
as your thought is also correct if u could cut a two smiles in the cup, keeping that área below the neck área i belive u will hit the gold.....
for mr Captain , maybe the crack´s develop under the stress caused by the increased noise and increased combustion pressure.... directly related to the holes being to large,
i beleve we have na agreement that opening the precups results in increased noise and ratle... if not my apologize.
<regards to america, the north stip
LOL... Then you really wont like what I am doing with my PCs lol...... I am going to machine a slot along all three front holes making a mouth so to speak.
I did not know we her in the USA had to be consistent "with what people is doing in here (europe)"
All in good fun, but races are not won by staying consistent with the competition lol..
[/quote]
hehe hhehe , i didn´t say that u´re walking the wrong road!!!! i was trying to say that u´re technic with the precups are far diff from what i experienced and what the fins/swedish/ germans and me portuguese do... i can explain the main idea behind my line of thought....
i tryed big holes , gained nothing remarkable (150cc pump) the remarkable gains were when i moved from stock 8x2.25 to 8x2.50.
i friend of mine has a W460 with the 617A i made a 120cc pump for him and we didn´t change the precups and the thing F$%#" rocks.
before i was fond of big holes thats why i tryied 3mm ones , and the only gain was noise , and ratle in idle, so i wonder .... the 8x the área of the 8 holes is far more than the neck área wich is 7mm. its not even necessary to use maths to see that.
if we take a look at the law´s ruling the flow in a section we can determine that being the exit área bigger than the section behind the velocity of the gas does not increase but it does decelerate wich causes increase in pressure , giving a false idea of improved performance.
it is my understanding that best way to go would be cutting the neck from 7mm to say 9mm and leave some of the holes alone , and increase the others but keeping the exit área 20 to 30% below the neck área , the idea is to gain velocity in the gas leaving the precup.
as your thought is also correct if u could cut a two smiles in the cup, keeping that área below the neck área i belive u will hit the gold.....
for mr Captain , maybe the crack´s develop under the stress caused by the increased noise and increased combustion pressure.... directly related to the holes being to large,
i beleve we have na agreement that opening the precups results in increased noise and ratle... if not my apologize.
<regards to america, the north stip
[/quote]
Mine actually quieted down with the larger USA size holes and that is with a lot more advance than I could run with stock PCs...
We know the math, been argued in this thread years ago. It sounds like you have found a good combination for your engine and tuning and fuel quality.
This seems to be like a topic as explosive as politics and religion lol... My days are arguing about it are long over.... USA can do it our way and Europe can do it theirs, that way we can all be right !! We can add the PC hole size to the many differences there are between American and European philosophy lol...
It all makes sense to me and I see what you are saying Barrote. The neck in my chambers were opened up also if I remember right. I did not notice Morse Diesel noise but also advanced the timing to around 30-31 degress which made the engine almost have a powerband. Pretty cool. Arguing is definitely a time waster but it is good to share opinion and what you have tried! When I get my engine rebuilt and these chambers back in that will be the real test!
yep , arguments , leave nowhere ....
my set up works great , thats what i have found but they do for street racer/roadracer not for drag machines as many members like...
maybe for a diff set up a diff aproach works better , who know´s as long as u´re happy with it ... i´ll be too.
are u guy´s still with the MW´s ?
(11-26-2015, 05:17 PM)barrote yep , arguments , leave nowhere ....
my set up works great , thats what i have found but they do for street racer/roadracer not for drag machines as many members like...
maybe for a diff set up a diff aproach works better , who know´s as long as u´re happy with it ... i´ll be too.
are u guy´s still with the MW´s ?
(11-26-2015, 05:17 PM)barrote yep , arguments , leave nowhere ....
my set up works great , thats what i have found but they do for street racer/roadracer not for drag machines as many members like...
maybe for a diff set up a diff aproach works better , who know´s as long as u´re happy with it ... i´ll be too.
are u guy´s still with the MW´s ?
They´re rare everywhere, just a few engines come with it , and this engines were N/A, trashed a long time ago. and it was only from 1976 to 1978 so 2 years gap in the production.
i´m working in a conversion to have the M for 60X engines fit the 617 , is almost done , when its done the 8mm version is good for 200cc to 250cc not bad at all. 7.5 mm for 150 to 180 , sounds good right !!!
i let u guys know of that , and sorry to be of topic here....
regards
Sounds great!
It's most likely the head cracked when the cooling system boiled.
This is the way I see it. Heat of combustion goes 3 ways. Out the exhaust, into mechanical energy to move the piston and into the cooling system. Advancing the timing or increasing the speed of the combustion event results in lower EGT's, which means the heat is going in 1 or both of the other directions. Since everyone who opens up the PC's say there's a power/torque benefit, it obviously raises BSFC, which means some of the heat removed from the exhaust is going to pushing the piston down. It would be dumb to think none of that heat goes into the cooling system too. That's all I'm saying. It may not be the main reason the cooling system boiled, but it didn't help.
(11-27-2015, 11:21 PM)raysorenson It's most likely the head cracked when the cooling system boiled.
This is the way I see it. Heat of combustion goes 3 ways. Out the exhaust, into mechanical energy to move the piston and into the cooling system. Advancing the timing or increasing the speed of the combustion event results in lower EGT's, which means the heat is going in 1 or both of the other directions. Since everyone who opens up the PC's say there's a power/torque benefit, it obviously raises BSFC, which means some of the heat removed from the exhaust is going to pushing the piston down. It would be dumb to think none of that heat goes into the cooling system too. That's all I'm saying. It may not be the main reason the cooling system boiled, but it didn't help.
(11-27-2015, 11:21 PM)raysorenson It's most likely the head cracked when the cooling system boiled.
This is the way I see it. Heat of combustion goes 3 ways. Out the exhaust, into mechanical energy to move the piston and into the cooling system. Advancing the timing or increasing the speed of the combustion event results in lower EGT's, which means the heat is going in 1 or both of the other directions. Since everyone who opens up the PC's say there's a power/torque benefit, it obviously raises BSFC, which means some of the heat removed from the exhaust is going to pushing the piston down. It would be dumb to think none of that heat goes into the cooling system too. That's all I'm saying. It may not be the main reason the cooling system boiled, but it didn't help.
larsalan I guess I need to look at this stupid ass drip shit. What you have to like mess with those elements on the pump? What a fucking hassle. then use some wire to hold the throttle open or some shit?
When I see those hogged out PCs I hear the war rig horn in my head!
Gotta pay to play, whatever killed it killed it. Higher boost levels, more fuel, etc. is definitely not easy on any engine.
You think about adding an extra coolant loop or two using the freeze plugs in the head?
larsalan I guess I need to look at this stupid ass drip shit. What you have to like mess with those elements on the pump? What a fucking hassle. then use some wire to hold the throttle open or some shit?
(12-03-2015, 08:04 PM)Simpler=Better When I see those hogged out PCs I hear the war rig horn in my head!
Gotta pay to play, whatever killed it killed it. Higher boost levels, more fuel, etc. is definitely not easy on any engine.
You think about adding an extra coolant loop or two using the freeze plugs in the head?
(12-03-2015, 08:04 PM)Simpler=Better When I see those hogged out PCs I hear the war rig horn in my head!
Gotta pay to play, whatever killed it killed it. Higher boost levels, more fuel, etc. is definitely not easy on any engine.
You think about adding an extra coolant loop or two using the freeze plugs in the head?
Put the car on the dyno after reamng out to .125" on all the holes except for the drain and the large hole. Results were 13 more ft/lbs torque, 3 more HP. I recommend doing this. Quick, easy and cheap way to get more go.
I forgot to mention the EGTs Also dropped about 150 degrees Fahrenheit. That mean time for more fuel!
Interesting! Same dyno I presume, 3hp isn't really much difference but...
I was thinking the other day and was wondering about installing later oblique injector 602/603 prechambers int a 617 head. Since those 1990s 616 PCs are so rare.
603.96 PC firing ducts are 1mm smaller OD than 617.95 ones, so either have to start with a "NA" head or have to install a sleeve around them (thermal conductivity issues?).
The orientation of the glowplug is also wrong... You'd need to find another way of preventing it from spining.
^617 n/a head & 603 n/a prechamber. You can also see, it sticks way out...
^L2R: OM603 n/a - /8 - MB100 angled inj. - W123 straight inj.
^You can see that the MB100 prechamber has the glowplug hole/locking tab in the right orientation. If this is of big interest, I can try to get the dimensions of the MB100 prechamber and a part number (not in my possesion but I know the guy who owns a set of 5). Don't know if the 617 Turbo also got a bigger dia neck prechamber like the 603 did?
(12-08-2015, 04:17 PM)Captain America I would like to spin the water pump faster! I remember talk of a smaller water pump pulley. I think 500 rpm would do it. I always let mine idle to cool exhaust temps to 400f or below before I shut it down and noticed that the coolant temp would come down a lot faster if the engine was at 1500 rpm vs 900-1000
(12-08-2015, 04:17 PM)Captain America I would like to spin the water pump faster! I remember talk of a smaller water pump pulley. I think 500 rpm would do it. I always let mine idle to cool exhaust temps to 400f or below before I shut it down and noticed that the coolant temp would come down a lot faster if the engine was at 1500 rpm vs 900-1000
(05-15-2016, 01:47 AM)DiseaselWeasel The orientation of the glowplug is also wrong... You'd need to find another way of preventing it from spining.
^You can see that the MB100 prechamber has the glowplug hole/locking tab in the right orientation. If this is of big interest, I can try to get the dimensions of the MB100 prechamber and a part number (not in my possesion but I know the guy who owns a set of 5). Don't know if the 617 Turbo also got a bigger dia neck prechamber like the 603 did?
(05-15-2016, 01:47 AM)DiseaselWeasel The orientation of the glowplug is also wrong... You'd need to find another way of preventing it from spining.
^You can see that the MB100 prechamber has the glowplug hole/locking tab in the right orientation. If this is of big interest, I can try to get the dimensions of the MB100 prechamber and a part number (not in my possesion but I know the guy who owns a set of 5). Don't know if the 617 Turbo also got a bigger dia neck prechamber like the 603 did?
No, that's a demonstration model. If the 617 turbo has 16mm dia, the MB100 prechambers are out. They have the same dimensions as the 617 n/a prechambers. Bonkers thought: those PCs are made from 2 pices anyway... I'm just nor sure how they are joined together. If you get my idea...
605/6 precups are off total diff sizes and shapes , but still the same concept .
they drop in the midle of head slightly ofset to exaust side , 8 X 2.25mm holes around the tipe evenly spaced and 10º ofset of each other in a 25º and 35º plane from horizontal.
neck diameter of 7mm, pre cup inside volume unknown to me, injector is bolted about 15 º from the vertical , the chamber "ball" is in the center so the injector stream should hit the ball aside. or in some cases most of the stream fails completely to hit the ball.
later on i´ll post a picture
regards