pistons
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2003 C230 racecar
Thread Starter
Junior Member
Joined: Dec 2010
Posts: 42
Likes: 0
2003 C230 racecar
Thread Starter
Junior Member
Joined: Dec 2010
Posts: 42
Likes: 0
2003 C230 racecar
The numbers still dont make sense. Stock the car runs 5-6psi and dynos around 160-167.
If your only making 280 whp at 40 psi that supercharger is way out of its efficiency range, IMHO its more of a heat pump at that boost then an air pump. Its not surprising your shattering pistons (not melting). You must be making an epic amount of tq.
You know eaton does custom remans right? If you massage that super charger right and build the bottom end you should have no problem making MB look really good, could be another 100hp in it for you. Depending on the rules in your class. Or you could even get the same power at a lower psi and make the car way more reliable.
Does your piston always break in the same place, it might be glow ignition from one of the valves heating up to red hot. Its a strange type of damage considering the piston looks good other then the chunk missing from the edge. Its certainly some form of violent detonation, is it too lean? I'm interested to see the grain structure at the failure, can you post pics?
New pistons are such a brute force way to fix the problem, have you thought about cryo treating stock ones?
If your only making 280 whp at 40 psi that supercharger is way out of its efficiency range, IMHO its more of a heat pump at that boost then an air pump. Its not surprising your shattering pistons (not melting). You must be making an epic amount of tq.
You know eaton does custom remans right? If you massage that super charger right and build the bottom end you should have no problem making MB look really good, could be another 100hp in it for you. Depending on the rules in your class. Or you could even get the same power at a lower psi and make the car way more reliable.
Does your piston always break in the same place, it might be glow ignition from one of the valves heating up to red hot. Its a strange type of damage considering the piston looks good other then the chunk missing from the edge. Its certainly some form of violent detonation, is it too lean? I'm interested to see the grain structure at the failure, can you post pics?
New pistons are such a brute force way to fix the problem, have you thought about cryo treating stock ones?
I got the result from the lab, and the metal expert tells me nothing has hit the pistons, it is strictly detonation, (bad tuning) so I have got some studying to do, here are some pics.
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From: KC, MO
"annoyance" and "self-righteousness", amoung others...
Sorry for misleading you, now I know the reason you keep saying the numbers don’t make sense, it’s not 40 psi, it’s 40kpa, and sometimes a turn the knob to 80kpa.
I got the result from the lab, and the metal expert tells me nothing has hit the pistons, it is strictly detonation, (bad tuning) so I have got some studying to do, here are some pics.
I got the result from the lab, and the metal expert tells me nothing has hit the pistons, it is strictly detonation, (bad tuning) so I have got some studying to do, here are some pics.
40kpa= 5.8psi
80kpa= 11.6psi
hmmm
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From: NYC
2007 C280 4Matic
In the short term you should get acquainted with data logging, and finding out when and why detonation occurs and tuning around that. (the R&D is half the fun)
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2003 C230 racecar
It all makes sense now. I've seen Evos and mazdas use 40psi all in the 400hp range it kind of sucks an MB cant do 11psi reliably. I do commend your dedication to the platform, you've gotten some nice gains out of the C230. New pistons are a must if you want more power, but reliability is a much bigger concern now. You might have to send your head out to have hot spots removed by cloverleafing the combustion chamber. New pistons now would be more resilient to breaking in the event of detonation but proper tuning would go along way to getting things in order.
In the short term you should get acquainted with data logging, and finding out when and why detonation occurs and tuning around that. (the R&D is half the fun)
In the short term you should get acquainted with data logging, and finding out when and why detonation occurs and tuning around that. (the R&D is half the fun)
Mi priorities are, make it safe, make it reliable, make it fast, unfortunately bi trying to make it fast I made it unreliable, hell I’m going backward. I know the 1.8L wasn’t meant to be a race engine but it’s fun trying, the 1.8L from Mb will be able to handle 11psi reliably after I’m done with it.
Never give up!
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From: sept-iles, quebec, canada
C280 2007 4matic
11 psi LOL just add some fuel to obtain 12.5 af ratio and retard timing few deg and keep an eye open on exhaust temp... keep it under 1400 deg f and you should be ok inside combustion chamber.
keep oil temp under 200 deg f, spray the underside of pistons and reliability should be ok
If you cant adjust timing .... water injection is a easy solution. very effective to prevent detonation from bad fuel or not enough octane.
i ran my old mazda at 18+ psi with 91 octane
windshield washer is a good media for cooling combustion chamber .
from my own experience with turbo-supercharger cars...
Yvan
keep oil temp under 200 deg f, spray the underside of pistons and reliability should be ok
If you cant adjust timing .... water injection is a easy solution. very effective to prevent detonation from bad fuel or not enough octane.
i ran my old mazda at 18+ psi with 91 octane
windshield washer is a good media for cooling combustion chamber .from my own experience with turbo-supercharger cars...
Yvan
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From: KC, MO
"annoyance" and "self-righteousness", amoung others...
So your head work includes a valve job? 3 angle, 5, or radius?
how extensive was the port and polish work?
how much did this cost USD?
larger valves or just the above? how about new lifters?
how extensive was the port and polish work?
how much did this cost USD?
larger valves or just the above? how about new lifters?
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2006 C350 Sport 6MT
Sorry for misleading you, now I know the reason you keep saying the numbers don’t make sense, it’s not 40 psi, it’s 40kpa, and sometimes a turn the knob to 80kpa.
I got the result from the lab, and the metal expert tells me nothing has hit the pistons, it is strictly detonation, (bad tuning) so I have got some studying to do, here are some pics.
I got the result from the lab, and the metal expert tells me nothing has hit the pistons, it is strictly detonation, (bad tuning) so I have got some studying to do, here are some pics.
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From: Raleigh, NC
2005 C230K, 2019 Honda CR-V, '74 Lotus Europa
I'm no expert on supercharged engines or pistons, but I have burned a few pistons in my youth! 
Usually it is from preignition caused by ignition timing or mixture, but with a super charger, maybe pressure is a consideration. I would think that pistons for supercharged engines would have a thicker top land above the compression ring. I'm sure your engine builder would know that, but it might be something to consider. Given that there doesn't seem to be much evidence of preignition (though there did look like a little), I wonder if pressure is more to blame...
What do your spark plugs look like? Are they a good color? Are the insulators broken up or is there other damage? That can give you a good indication of what is happening in the combustion chamber.
I'm sure none of this is anything new to whoever is analyzing your pistons. I just had to spout off so I could sound like I knew something!
Be sure you let us know what you find out.
Usually it is from preignition caused by ignition timing or mixture, but with a super charger, maybe pressure is a consideration. I would think that pistons for supercharged engines would have a thicker top land above the compression ring. I'm sure your engine builder would know that, but it might be something to consider. Given that there doesn't seem to be much evidence of preignition (though there did look like a little), I wonder if pressure is more to blame...
What do your spark plugs look like? Are they a good color? Are the insulators broken up or is there other damage? That can give you a good indication of what is happening in the combustion chamber.
I'm sure none of this is anything new to whoever is analyzing your pistons. I just had to spout off so I could sound like I knew something!
Be sure you let us know what you find out.
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Joined: Apr 2007
Posts: 134
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From: Durham NC
2006 ML350 back from dealer after 4 weeks,now back for oil consumption test!,2003 C230 Sport
I wonder why no big Merc tuner like Brabus etc... has come out with an tuning package like this for 230k. Its like all the tuners gave up on it. With all the options for AMG motors that Brabus make. Tuning a 4 banger would be easy for them. It has to be more W203 c230 than any other Benz on the roads. So they would make money on it. Can you imagine the amount of money an blow pistons Brabus must have had in tuning that EV -12 800 hp 
monster!
monster!
Thread Starter
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2003 C230 racecar
11 psi LOL just add some fuel to obtain 12.5 af ratio and retard timing few deg and keep an eye open on exhaust temp... keep it under 1400 deg f and you should be ok inside combustion chamber.
keep oil temp under 200 deg f, spray the underside of pistons and reliability should be ok
If you cant adjust timing .... water injection is a easy solution. very effective to prevent detonation from bad fuel or not enough octane.
i ran my old mazda at 18+ psi with 91 octane windshield washer is a good media for cooling combustion chamber .
from my own experience with turbo-supercharger cars...
Yvan
keep oil temp under 200 deg f, spray the underside of pistons and reliability should be ok
If you cant adjust timing .... water injection is a easy solution. very effective to prevent detonation from bad fuel or not enough octane.
i ran my old mazda at 18+ psi with 91 octane
windshield washer is a good media for cooling combustion chamber .from my own experience with turbo-supercharger cars...
Yvan
Yvan, I think you have don it, I’m running 13 af, 40 deg total timing at 6000 rpm, and I am only having problems at two tracks, Calabogy and Deux Montagne, we have to run mufflers, probably to much resistance and overheating, has you say I’ll keep mi eye on exhaust temp. Thanks for your input.
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2003 C230 racecar
Extensive, well from the before and after result that were produced from the flow test I would say it was extensive, it cost 3995.00 + 199.75 tax can$ that was in 2008, I cant remember what the exchange rate was at that time.
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From: sept-iles, quebec, canada
C280 2007 4matic
40 deg !!!
with a central plug on 4v head i thing it is a lot too much ( my idea )
on this type of head i never put timing over 24-25 deg...
on old ford 2 v head... 25-30 deg max.
with too much timing you put an enormous stress on pistion-rod
the only good way to fing the timing on a specific engine is on a dyno
find the timing at each rpm-load with the biggest torq output then back 2 deg for safety
good luck
Yvan
with a central plug on 4v head i thing it is a lot too much ( my idea )
on this type of head i never put timing over 24-25 deg...
on old ford 2 v head... 25-30 deg max.
with too much timing you put an enormous stress on pistion-rod
the only good way to fing the timing on a specific engine is on a dyno
find the timing at each rpm-load with the biggest torq output then back 2 deg for safety
good luck
Yvan
Thread Starter
Junior Member
Joined: Dec 2010
Posts: 42
Likes: 0
2003 C230 racecar
I'm no expert on supercharged engines or pistons, but I have burned a few pistons in my youth!
Usually it is from preignition caused by ignition timing or mixture, but with a super charger, maybe pressure is a consideration. I would think that pistons for supercharged engines would have a thicker top land above the compression ring. I'm sure your engine builder would know that, but it might be something to consider. Given that there doesn't seem to be much evidence of preignition (though there did look like a little), I wonder if pressure is more to blame...
What do your spark plugs look like? Are they a good color? Are the insulators broken up or is there other damage? That can give you a good indication of what is happening in the combustion chamber.
I'm sure none of this is anything new to whoever is analyzing your pistons. I just had to spout off so I could sound like I knew something!
Be sure you let us know what you find out.
Usually it is from preignition caused by ignition timing or mixture, but with a super charger, maybe pressure is a consideration. I would think that pistons for supercharged engines would have a thicker top land above the compression ring. I'm sure your engine builder would know that, but it might be something to consider. Given that there doesn't seem to be much evidence of preignition (though there did look like a little), I wonder if pressure is more to blame...
What do your spark plugs look like? Are they a good color? Are the insulators broken up or is there other damage? That can give you a good indication of what is happening in the combustion chamber.
I'm sure none of this is anything new to whoever is analyzing your pistons. I just had to spout off so I could sound like I knew something!
Be sure you let us know what you find out.
I will keep you posted.
Thread Starter
Junior Member
Joined: Dec 2010
Posts: 42
Likes: 0
2003 C230 racecar
40 deg !!!
with a central plug on 4v head i thing it is a lot too much ( my idea )
on this type of head i never put timing over 24-25 deg...
on old ford 2 v head... 25-30 deg max.
with too much timing you put an enormous stress on pistion-rod
the only good way to fing the timing on a specific engine is on a dyno
find the timing at each rpm-load with the biggest torq output then back 2 deg for safety
good luck
Yvan
with a central plug on 4v head i thing it is a lot too much ( my idea )
on this type of head i never put timing over 24-25 deg...
on old ford 2 v head... 25-30 deg max.
with too much timing you put an enormous stress on pistion-rod
the only good way to fing the timing on a specific engine is on a dyno
find the timing at each rpm-load with the biggest torq output then back 2 deg for safety
good luck
Yvan
Thanks
MBWorld Fanatic!
Joined: Sep 2010
Posts: 1,434
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From: Raleigh, NC
2005 C230K, 2019 Honda CR-V, '74 Lotus Europa
40 deg. seems like a lot to me, too. I looked up the spec for my BDA (normally aspirated, twin cam, 4v carburated Ford): 30 at 6000 rpm. Obviously, our motors are very different, but 10 degrees seems like a pretty large difference.
Thread Starter
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2003 C230 racecar
Question;
I’ve been looking for the head dimensions for a 1.8L on the net, cant fine anything.
What I am looking for is the thickness of a standard head from the valve cover to the head gasket, or the combustion chamber’s dept, the reason for asking is I have been corresponding with VRP the people that has done the work on the head, they tell me they have not cut the head to increase the compression ratio, however on the bill it sais resurfacing? If someone has that information please let me know.
Thanks
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300E a couple 1994 w124wagon E320 Wagon/,1971MGB Track/Rally, MG Midget Autocross ,2000 E320 wagon.
OEM
pistons way to much compression for 11lbs boost.
Mill a dish or run thick head gasket and get it down into the 8.5-9cr zone.
Your problem will vanish.
Or did someone suggest this already?
Mill a dish or run thick head gasket and get it down into the 8.5-9cr zone.
Your problem will vanish.
Or did someone suggest this already?
Thread Starter
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2003 C230 racecar
