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I have one question guys, maybe you can help me out. There is a manual that comes with conrods, there it says that ARP L19 conrod bolts must be tightened with the 51ft-lbs torque value. That’s what we did, we torqued it gradually to this value. We have never measured stretch value as below you can see that these bolts don’t require it. My mechanic says that he finds it little bit odd that the torque value is so low, but did it anyways. Tasos never spoke about this in his videos. So we are going by the manual, but any opinion would be helpful.
hi.. i just checked my rod and i have ARP 2000 5/16 bolts and 37 ft libs.. so i check with maker they say you can go +5ft lb more, but more than.. so yours are still good, so you can do it as itis.. i have friend he had bmw l19 bolts he torque same as your 75 nm.. don't go more....
One more question guys. Since now I have a sleeved (Darton MID) engine with italianrp conrods and pistons, there is a different material involved when it comes to friction between engine elements, as there is no nikasil on cylinder walls anymore. Should I still use a regular AMG 5W-40 engine oil or is there a different type of oil recommended for forged internals? Any opinions?
Use regular 0-40 . Then after 800 miles change your oil and filter, after 1600 miles change your oil and filter again but this time using a 5w50 oil of your choice. Do not use 0-40 on this built motor after your break in period . This oil breaks down , thins out and have excessive blow by. . Stay with 5w50 and you will have much better protection, better oil temp control, less blow by and better ring to wall seal. You will find small metals in your filter, do not be alarmed. This is normal break in wear and once you reach your third oil change you should have non present .. I'm already 3 years in with a built
engine, I also have a spare on the side that I use for part building and as a back up. I also have had another built motor installed in a customers cls. Using 5w 50 with fantastic results.
If you need any additional info feel free to ask.
Use regular 0-40 . Then after 800 miles change your oil and filter, after 1600 miles change your oil and filter again but this time using a 5w50 oil of your choice. Do not use 0-40 on this built motor after your break in period . This oil breaks down , thins out and have excessive blow by. . Stay with 5w50 and you will have much better protection, better oil temp control, less blow by and better ring to wall seal. You will find small metals in your filter, do not be alarmed. This is normal break in wear and once you reach your third oil change you should have non present .. I'm already 3 years in with a built
engine, I also have a spare on the side that I use for part building and as a back up. I also have had another built motor installed in a customers cls. Using 5w 50 with fantastic results.
If you need any additional info feel free to ask.
where are you based? I am in Eastern Europe, we have really cold winters here, so I am thinking maybe 0W-40 in winter and 5W-50 in summer…
I would consider break-in specific oil run until reaching operating temp. Then 10-30 dino oil changed at 100 , 200 500 750 and 1000 miles. At 3000 miles switch to Your preferred syn weight oil.
where are you based? I am in Eastern Europe, we have really cold winters here, so I am thinking maybe 0W-40 in winter and 5W-50 in summer…
New York . Gets very cold . If that your plan, then atleast do 5-40 winter 5w50 summer. Then send you oil put for an oil analysis to confirm the oil weight recommended is indeed working as I've stated. Showing you good longer lasting protection with minimal viscosity break down , especially at higher power levels running much more fuel that has a tendency to contaminate the oil and thin it out .
I just watched this video and it explains how the M157 bend rods. It's not the material, it's the design - from the piston all the way to the way clearances are on the rods:
Our friend is having trouble with English. He is right. Piston steered rods are a recipe for disaster with more boost in an engine that is not fresh. Crank steered rods make use of thrust surfaces on each side of the big end of the rod to keep the rod in the same position relative to the pin and thus; the piston. More stable; able to live with more boost with more wear.
All of this assumes....
A stable crankshaft.... hopefully forged steel... good crank thrust control... set up correctly with enough thrust bearing that it doesn’t wear out prematurely.... I prefer to see thrust bearings with the thrust surface built into the bearing shells. But the engineers do what they will and changing from the cheesy half moon thrust inserts (which I have had no failures with in my stoopid frenchie V6 things boosted to increase power and torque to four times what they made naturally aspirated) to a thrust shell will be quite the trick.
Strong H-Beam steel rods for a boosted engine; hopefully with more thrust surface on each side of the big end so when assembled with .002” of space between the pair of rods there is plenty of surface area for any side loads to be applied to the crankshaft.
A large diameter wrist wrist pin for maximum area applied to the rod. More area for applied load is more safety.
Modern forged pistons with all the current tricks .... Win!
Our boosted engines are not getting wound to a telephone number so no need for heroics like titanium rods to reduce reciprocating weight.
Hi guys, I need your recommendation. We are about 1-2 weeks before everything is finished. I need to decide which spark plugs will be used. Either OEM MB or Weistec 1-step colder. These: https://www.weistec.com/spark-plug-set-m157-m278.html
I had occasional misfires before catastrophic engine failure, I have tried these Weistec spark plugs and it looked like the problem was solved, but I managed to put only like 2k miles before engine blew, so who knows.
I am little bit paranoid whether I should use non-OEM plugs, but on my power levels colder plugs are recommended.
I know several who are tuned and use the stock MB OEM plug from Bosch with tighter gap which has worked well.
I personally have been using NGK 1555 plugs with stock gap and been pleased with them but my tune isn’t crazy it’s an AMS 100 oct and a AMS 93 Oct tune with intakes. These also index pretty close to the 12 o clock position at 23NM torque without having to sand down the washers like some do on the MB OEM plug.
I will say once I refreshed my coil packs with the plugs I’ve never had a misfire. When my call packs were 6 to 7 years old, I went through two or three sets of plugs, thinking it was a Plugs causing this fires, but it was the degraded coils
Yes, a bad fuel injector was probably the cause of this failure. Some cylinder walls had scoring, so it wasn’t perfectly healthy anyways. Do I risk anything if I run stock OEM spark plugs?
Yes, a bad fuel injector was probably the cause of this failure. Some cylinder walls had scoring, so it wasn’t perfectly healthy anyways. Do I risk anything if I run stock OEM spark plugs?
i think if you plan on replacing the plugs every 5-10k miles and driving the car hard, OEM plugs are fine. I'm running OEM plugs and gap on 100 octane tune. We are happy.
i would go colder like ngk if you space out the change out intervals more. Less likely to foul the plug and less likely to have a tip break off ...
there is not enough real empiric data to answer your question adequately - it's mostly anecdotal and lots of confirmation bias here from people that have never had issues with "their plugs." Doesn't mean they won't have issues eventually.
the people that see the most tunes consistently and get feedback (good and bad) are the tuners hence it's theoretically a good idea to heed their recommendation on what plugs to use. Just my $0.02
Yes, a bad fuel injector was probably the cause of this failure. Some cylinder walls had scoring, so it wasn’t perfectly healthy anyways. Do I risk anything if I run stock OEM spark plugs?
would STRONGLY suggest getting new Beru coil packs if you have more than 10k miles of tuned driving on your current coils and they're not newer. coils 1 & 5 by the turbochargers take some intense heat from the turbo and degrades them much faster than the other coils. I have the same 100 oct tune as @PeterUbers and had replaced my plugs with OEM but was still getting occasional misfires until i replaced the coil packs. later I switched to the NGK 1555's and have not had any problems but am definitely planning to change plugs every 5k tuned miles and likely coils at 10k or if misfires start coming up again. people focus a lot on the plugs, but for these M157 motors who are tuned the coils definitely need to be monitored/replaced somewhere in the 10k-15k range if you start seeing misfires.
Yes, a bad fuel injector was probably the cause of this failure. Some cylinder walls had scoring, so it wasn’t perfectly healthy anyways. Do I risk anything if I run stock OEM spark plugs?
your engine is built . Your running darton sleeves . The cylinder temps in our engine is different then that of a stock block . Iron takes longer to dissipate heat to the coolant that circulates through the block . Meaning at times cylinder heat/ pressure will be higher then that of a stock block . I highly recommend you go with colder plugs, the brand as long as it's reputable and gap correct shouldn't be a problem although using plugs that other use problem free should be your go to plug . Go colder. I'm going on 3 years now and have 2 built m157 both with iron sleeves . I'm 2 steps colder but 1 step is good enough
I am finally taking the car from the workshop during the weekend. 8 long months of waiting. I will have a drive-in period of about 1000 miles before an oil change. Are there any specific rules or some unwritten common knowledge regarding drive-in period for modified cars like mine? Since my car has darton mid sleeves and forged pistons/rods I have no idea whether I should take an extra care while running in. Any recommendation will be much appreciated.
I am finally taking the car from the workshop during the weekend. 8 long months of waiting. I will have a drive-in period of about 1000 miles before an oil change. Are there any specific rules or some unwritten common knowledge regarding drive-in period for modified cars like mine? Since my car has darton mid sleeves and forged pistons/rods I have no idea whether I should take an extra care while running in. Any recommendation will be much appreciated.
i have no idea on specific rules but congrats! You are a patient man and kind to update us faithfully
What did your (re)builder of the engine recommend?
Last edited by PeterUbers; Dec 6, 2023 at 12:34 PM.
I would change the oil at 300 miles or less. Lots of machine work and rebuild leads to lots of unfriendly particles. I would guess with the cost of this endeavor that an oil change will be a minuscule amount and probably will go a long way.
i have no idea on specific rules but congrats! You are a patient man and kind to update us faithfully
What did your (re)builder of the engine recommend?
Thanks, I can’t wait to see if I feel any difference as far as vibrations and idle/cold start go. He said nothing special, just to be gentle with the engine, first 1000 miles never push the engine, really just extremely relaxed driving. He says that those guys who push the engine from 0 miles are taking risks.
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