prechambers mods?
prechambers mods?
Hey guys. I was brainstorming in my mind about modding the pre chambers. especially the outflow of the chambers. Entirely deleting the "bulb" or drill extra holes. I can imagine it improving gas flow, when you're at 3 bar and +5500 rpm it kinda looks like a restriction. I can also see it give to much "oempf" to the piston at once, giving them some serious "piston slap". I don't know how to describe it, or the English word but i mean when the piston goes upwards on the right side on the cilinder and bangs agains the left side when going down. I can already hear this on my engine and some STD on youtube. I mean that nailing sound.
So, whats the reason why it's restricted? Could there be any improvement? and would it harm the engine? I'm just curious...
There is an extensive, but maybe not exhaustive discussion of this in the archives. Search it up, or maybe some kinder soul than i will link you to it.
The only possible explanation for the positive results seen with hogging out the prechamber holes is that thermodynamic efficiency is increased at high loads. There's lots of heat moved from the prechamber to the cooling system, which is waste. Direct injected engines don't have this heat sink problem, and they're more efficient. Hope this helps:-)
Jeemu and several other engine builders have stated that making the holes bigger helps a lot. You can't cut the end off, it would eliminate the whole design behind an IDI. You can if you replace stock injectors with direct injection units, but that involves changing pistons and is a very complicated process.
Several members having modded prechambers with success. Captain America being one of them, I am going to do this mod in the near future
Personally I've heard enough positive reviews on this that I'm going to try it. Maybe a ~20% enlargement of all holes.
MFSuper90, do you have prechamber removal tools?
Intresting! I thought of it making the engine better. But the heat inefficiency seems kinda strange. Full load on a idi engine always makes more heat in my opinion. The combustion takes place in the head. And at full load with black smoke there's no air to isolate the heat. Making the engine run hotter. I thought giving the prechamber more flow it would direct the gasses to the cylinder, where there's more air for the isolation.
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?
CAPTAIN AMERICA GET IN HERE
http://www.superturbodiesel.com/std/Thre...lame-Front
http://www.superturbodiesel.com/std/Thre...-s-82-300D
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?
(06-02-2014, 05:53 AM)Tito Intresting! I thought of it making the engine better. But the heat inefficiency seems kinda strange. Full load on a idi engine always makes more heat in my opinion. The combustion takes place in the head. And at full load with black smoke there's no air to isolate the heat. Making the engine run hotter. I thought giving the prechamber more flow it would direct the gasses to the cylinder, where there's more air for the isolation.
SAE #790039 The lower efficiency of the indirect-injection diesel engine, with respect to the direct injection type, is due to additional heat transfer from the combustion chamber, gas pumping between chambers, later injection timing and a different burning rate schedule.
(06-02-2014, 05:53 AM)Tito Intresting! I thought of it making the engine better. But the heat inefficiency seems kinda strange. Full load on a idi engine always makes more heat in my opinion. The combustion takes place in the head. And at full load with black smoke there's no air to isolate the heat. Making the engine run hotter. I thought giving the prechamber more flow it would direct the gasses to the cylinder, where there's more air for the isolation.
SAE #790039 The lower efficiency of the indirect-injection diesel engine, with respect to the direct injection type, is due to additional heat transfer from the combustion chamber, gas pumping between chambers, later injection timing and a different burning rate schedule.
(06-01-2014, 08:16 PM)led-panzer MFSuper90, do you have prechamber removal tools?
(06-01-2014, 08:16 PM)led-panzer MFSuper90, do you have prechamber removal tools?
Well, i'm definably going to try this. Thinking about a 20~30% bigger holes. It's for a om606 which I want to push 500hp. Also going to flow the head one of these days. I'm curious about the result. However I think I never get to notice it since I've never driven the stock pre chambers.
Edit, How about drilling one hole straight down?
(06-03-2014, 02:28 PM)MFSuper90(06-01-2014, 08:16 PM)led-panzer MFSuper90, do you have prechamber removal tools?
Yup, I made a tool to remove them. I removed a set in a blown engine I had, worked pretty well.
(06-03-2014, 02:28 PM)MFSuper90(06-01-2014, 08:16 PM)led-panzer MFSuper90, do you have prechamber removal tools?
Yup, I made a tool to remove them. I removed a set in a blown engine I had, worked pretty well.
(06-03-2014, 03:49 PM)Tito Well, i'm definably going to try this. Thinking about a 20~30% bigger holes. It's for a om606 which I want to push 500hp. Also going to flow the head one of these days. I'm curious about the result. However I think I never get to notice it since I've never driven the stock pre chambers.
Edit, How about drilling one hole straight down?
(06-03-2014, 03:49 PM)Tito Well, i'm definably going to try this. Thinking about a 20~30% bigger holes. It's for a om606 which I want to push 500hp. Also going to flow the head one of these days. I'm curious about the result. However I think I never get to notice it since I've never driven the stock pre chambers.
Edit, How about drilling one hole straight down?
I'll summon the captain
3 front holes to .156" rear two and bottom to .125”
Stock (broken) 1985 prechamber on the left and big baller Simpler=Better ported chamber on the right
So I have turned the fuel up (torque capsule) a lot! And also an unknown amount.... My EGTs only max at about 900 so I have much moar room to go I think. Also I might add that I'm making 14-15 psi with my Garrett w/ 60 trim compressor. Inter cooler not yet operational and Injection timing max advanced (didn't check what it actually is)
My 300 rips, and my transmission is dying (like most I guess) haha. She will be getting a AX-15 when money permits. Back to the subject though, I have been running this setup since beginning of February and even though Mr. OM616 recommended not to drill the bottom hole, we did anyway haha. Just on the fact that we were going for broke, kinda. I didn't want to stay too safe and have to pull, drill, ream, deburr, twice. My OM617 runs flawlessly!!!! I've been to the desert where I've been up hills that $40,000 four wheel drives couldn't make. I've pulled an old broken down F150 10 miles to my shop that research shows weighs about 5000lbs with no issues. It amazes people haha. And it starts cold with a flick of the ignition switch after the glow plugs have been on for 5 seconds.
(06-04-2014, 05:44 AM)baldur Well consider this. At TDC, how much of the combustion chamber volume is inside the prechamber?
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?
(06-04-2014, 05:44 AM)baldur Well consider this. At TDC, how much of the combustion chamber volume is inside the prechamber?
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?
Were captain's new or just old ones cleaned up?
(06-04-2014, 09:41 AM)sassparilla_kid Were captain's new or just old ones cleaned up?
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?
(06-04-2014, 09:41 AM)sassparilla_kid Were captain's new or just old ones cleaned up?
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?
(06-04-2014, 11:15 AM)Simpler=Better(06-04-2014, 09:41 AM)sassparilla_kid Were captain's new or just old ones cleaned up?
Oldies, he did a great job cleaning them though
(06-04-2014, 11:15 AM)Simpler=Better(06-04-2014, 09:41 AM)sassparilla_kid Were captain's new or just old ones cleaned up?
Oldies, he did a great job cleaning them though
(06-04-2014, 03:45 PM)MFSuper90(06-04-2014, 11:15 AM)Simpler=Better(06-04-2014, 09:41 AM)sassparilla_kid Were captain's new or just old ones cleaned up?
Oldies, he did a great job cleaning them though
So if I blast mine and clean them up, would you entertain the idea of reaming them like capt's? The only stipulation being I wouldn't want the bottom hole done.
And of course I would pay you for your time and effort.
I bought a reamer with the intentions of doing it myself, but bought a tapered one because I am an idiot. Seems more reasonable to pay someone than buy a tool that I will only use once
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?
(06-04-2014, 03:45 PM)MFSuper90(06-04-2014, 11:15 AM)Simpler=Better(06-04-2014, 09:41 AM)sassparilla_kid Were captain's new or just old ones cleaned up?
Oldies, he did a great job cleaning them though
So if I blast mine and clean them up, would you entertain the idea of reaming them like capt's? The only stipulation being I wouldn't want the bottom hole done.
And of course I would pay you for your time and effort.
I bought a reamer with the intentions of doing it myself, but bought a tapered one because I am an idiot. Seems more reasonable to pay someone than buy a tool that I will only use once
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?
Time to bust out the lathe!!! Lol
(06-05-2014, 09:07 AM)sassparilla_kid Time to bust out the lathe!!! Lol
(06-05-2014, 09:23 AM)MFSuper90(06-05-2014, 09:07 AM)sassparilla_kid Time to bust out the lathe!!! Lol
What are you going to do with the lathe?
(06-05-2014, 09:23 AM)MFSuper90(06-05-2014, 09:07 AM)sassparilla_kid Time to bust out the lathe!!! Lol
What are you going to do with the lathe?
(06-05-2014, 09:29 AM)Duncansport(06-05-2014, 09:23 AM)MFSuper90(06-05-2014, 09:07 AM)sassparilla_kid Time to bust out the lathe!!! Lol
What are you going to do with the lathe?
Tear your hand off while trying to rheam out the PC's clearly
(06-05-2014, 09:29 AM)Duncansport(06-05-2014, 09:23 AM)MFSuper90(06-05-2014, 09:07 AM)sassparilla_kid Time to bust out the lathe!!! Lol
What are you going to do with the lathe?
Tear your hand off while trying to rheam out the PC's clearly
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?
Well, the hole diameter in the injector seat can be opened up as well so that part is done on a lathe. If you were good with a 4jaw and angle blocks I guess you could jig it up...would take 500 years though
EDIT: hole diameter in the injector seat, not burn tube. my bad.
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?
(06-05-2014, 11:17 AM)Simpler=Better Well, the burn tube can be opened up as well so that part is done on a lathe.
(06-05-2014, 11:17 AM)Simpler=Better Well, the burn tube can be opened up as well so that part is done on a lathe.
Idk, I was barely awake. I forgot all the holes are on the sides lol
(06-05-2014, 12:05 PM)OM616(06-05-2014, 11:17 AM)Simpler=Better Well, the burn tube can be opened up as well so that part is done on a lathe.The next time I do a PC, I am going to machine a slot across the three burn holes making a mouth so to speak.
(06-05-2014, 12:05 PM)OM616(06-05-2014, 11:17 AM)Simpler=Better Well, the burn tube can be opened up as well so that part is done on a lathe.The next time I do a PC, I am going to machine a slot across the three burn holes making a mouth so to speak.
hy there,
in my set up i will reopen the holes a bit, from 8 holes at 2,2 mm , i will have 8 X 2,5 mm, the botom one is 1,5mm and will stay the same for the moment. (606.04 pre cups). the pre cups marked 606.02 usually found in N/A engines are 8x2.1mm and botom hole at 1.3 or 1.4. , from this differnce one can understand that increasing fueling , involuntarly needs increasing the holes área or nr of holes etc.
taking acount the laws wich rule flow, increasing the holes beon the área of te neck hole will produce any significant gain, at least thats my bet. since the neck diameter is not more than 10mm (just guessing) i can´t see any gain using a hole wider than 2.50 , to 2,75 mm.
i´m trying the 2.5 mm .
let u know my findings.
any how, would be interesting to know if someone had opened the holes more than 2.5mm with positive results .
regards
So, I finaly started drilling them... It's the worst job ever.
First tried to drill with a 3mm hss drill bit. Took about an hour for one hole. Then found out could better use a grinded stone drill bit
If anyone is also trying this, rember to take out the glow plugs
Only problem I'm running into now is that everytime I get to the end of the hole, the drill bit grips and snaps off. So I'm drilling them till the last half mm or something and I'll need to find out how to drill the last bit.
HSS cr 0.7 drill bits , makes wonders . i use the brand BERNER germany . buy some 3 or 4. one lasts only one hole, then Sharp it do another one. in one hour is possible to drill all of them .
the best device is the electric screw driver( or the hell it is called in english) in high speed leave only 5mm of drill bit ouside, like that u can spare the bits.
i did 3 mm and 2mm at center. i did not tried them yet.
bonne chance.
PS: drill at dry conditions.
I think they are like butter to drill in, if you heat them up
All modified prechamber pictures from jeemu is red gloving
(12-08-2014, 05:59 PM)swatmugga Hey Tito
Why did you made the holes so big? I don't think that was a good idea. What were your thoughts?
You tripled the cross section of the holes!
Cobalt drill bits... I guess they don't come from the diy store? I used 5 stone drill bits, which where done after drilling 3 chambers, but mainly because the end gripped and only the tip is hardened. So it could pay off buying a cobalt drill bit.
(12-08-2014, 05:59 PM)swatmugga Hey Tito
Why did you made the holes so big? I don't think that was a good idea. What were your thoughts?
You tripled the cross section of the holes!
hy there,
a pack of 10 x3mm HSS Cr 0.7 drill bits (those cobalt) maybe cost 15€ i dont think the issue is the cost. and amasing is that the drill bit u can Sharp. use again and again til the bit is over. i went through the same usually ending the hole is tricky thats why u shoul use a hand driller.
the inside hole is 6,7mm on the pre cups marked 606 02.
heating the PC wont do any good, what one could do is heating to where we can distemper the metal and after doing the holes heat treat them again for hardning . something is not so easy to do. simply cause we dont know the cokking temp.
regards
Colbalt drill bits work the best, flexible but still hard. Carbide too brittle for smaller holes. I usually use only one drill bit per hole, except the back holes ,hole too close to drilled size,must sharpen bits, small size bits brake easy. Do not need to heat prechambers, Have done eight sets . Using hand drill.
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?
Captain disagrees:
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?
What are the stock hole sizes? And Simpler I think Hercules is saying +6%> +8%> +10%> stock in terms of performance
(12-12-2014, 10:50 AM)DiseaselWeasel Next step: direct injection.
(12-12-2014, 10:50 AM)DiseaselWeasel Next step: direct injection.
yep ,
i thought about the same, thing is where to find a VE 5 full mechanichal. or lucas i belive.
injectors are piece of cake.
in europe the w210 E290 comes with a 602 DI lucas electrical pump.
if i could lay my hands on a VE5 mechanical with a MB flange ..... i´m dreaming boys
regards
ps: i have my pre cups ready , just missing the special tool to remove them.
(12-12-2014, 03:32 PM)barrote yep ,
i thought about the same, thing is where to find a VE 5 full mechanichal. or lucas i belive.
injectors are piece of cake.
in europe the w210 E290 comes with a 602 DI lucas electrical pump.
if i could lay my hands on a VE5 mechanical with a MB flange ..... i´m dreaming boys
regards
ps: i have my pre cups ready , just missing the special tool to remove them.
(12-12-2014, 03:32 PM)barrote yep ,
i thought about the same, thing is where to find a VE 5 full mechanichal. or lucas i belive.
injectors are piece of cake.
in europe the w210 E290 comes with a 602 DI lucas electrical pump.
if i could lay my hands on a VE5 mechanical with a MB flange ..... i´m dreaming boys
regards
ps: i have my pre cups ready , just missing the special tool to remove them.