Major flaw in the Mitsubishi 4B11 engine and its not the Rods!
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Conrad
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do you have experince of them?
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I cant answer that as I dont rally nor have I ever setup a car for rallying... hopefully somone knows though:lol: Do group N rally cars have to keep stock rods???What, in the current stage of developement, is the maximum torque a 4B11T can safely produce at 3500(ish) rev/min?
Assume a turbo capable of 3.5barA and FIA "turbo" fuel
Grant
Personally, "if" I was running a 4B11t I wouldnt risk the engine being completely destroyed trying to squeeze large amounts of power out of it on standard parts knowing at some point it will let go. Its not "if" more "when". I would rather spend a couple of ÂŁK on rods, pistons, valves and springs than a couple of ÂŁK just replacing the 4B11t with another standard 4B11t unit when it lets go. Its a no brainer, peace of mind and strength for the upgrades.
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In theory yes
but it doesn't stop the manufacturer homologating a "Variant Option" which just happens to have the same weight and principle dimensions as an OEM rod See the "bent rod" thread
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^^^^^ 100% agree
Gum, I dont see how the 4B11t can be such a great engine... granted the head design in terms of flow seems to be more advanced than the 4G63 but you would expect this as its a newer engine design. Pity all the other flaws are letting it down, the block is weaker (than 4G63) and requires sleeves, the rods are not holding up too well even on standard un modified cars, piston ring lands failing due to ring gapa and a few cars with dropped valves.
It looks like you have to take the 4B11t and create a new engine from it using aftermarket parts
It looks like you have to take the 4B11t and create a new engine from it using aftermarket parts
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Its worse than bear baiting:crackup:Gum, I dont see how the 4B11t can be such a great engine... granted the head design in terms of flow seems to be more advanced than the 4G63 but you would expect this as its a newer engine design. Pity all the other flaws are letting it down, the block is weaker (than 4G63) and requires sleeves, the rods are not holding up too well even on standard un modified cars, piston ring lands failing due to ring gapa and a few cars with dropped valves.
It looks like you have to take the 4B11t and create a new engine from it using aftermarket parts
Few, too, seems speculative and unqualified
Evidence of the standard, non modified, no bolt on failures please
And are 4g63's not known to throw rods below 400bhp?
Again you say the engine has a flaw
Its design includes an alloy block that requires sleeving, how is that a flaw?
Not at all.Its worse than bear baiting:crackup:
Few, too, seems speculative and unqualified
Evidence of the standard, non modified, no bolt on failures please
And are 4g63's not known to throw rods below 400bhp?
Again you say the engine has a flaw
Its design includes an alloy block that requires sleeving, how is that a flaw?
Try the search button on here and evoM for your answers.
I didnt say it had a flaw, the link was to a thread that says that
But now you mention it,
do you not consider rods through the side of the block a flaw?
or piston ring lands failing due to incorrect gap clearances a flaw?
or valves dropping a flaw?
The block needs resleeving to run big power
Is that not a flaw in the standard sleeves then?Does the 4G63 or 4G64 block need sleeves to run big power?
and yes.... I have experience of a sleeved block and it wasnt a good one :wallbang:
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Sorry i took this to be your opinion:I didnt say it had a flaw, the link was to a thread that says that
But now you mention it,
do you not consider rods through the side of the block a flaw?
or piston ring lands failing due to incorrect gap clearances a flaw?
or valves dropping a flaw?
The block needs resleeving to run big power
Does the 4G63 or 4G64 block need sleeves to run big power?
and yes.... I have experience of a sleeved block and it wasnt a good one :wallbang:
If you fly to close to the sun, you're going to get burned..simples.
Those issues you speak of are flaws in the sense that they are not expected to happen in a normal functioning sense. Nothing is 100% perfect and clearly the 4b11T isn't trying to debunk that truth. How has it been analayzed to come to the conclusion that it is ring gaps that is causing ringland failure? There are other factors to consider which info about wasn't given on.
It appears that you consider it a flawed engine as a result of having and needing sleeved bores to run big power. The car was NEVER designed to run big power in its original state, so does the flaw lie with the engine and manufacturer or the person/tuner who believes he can make the engine run big power without modding. Again I would love to see some examples and numbers of this on what was a totally standard car.
I thought in the thread you posted there was some very good discussion about points as to why this could be happening. Even bolt ons will alter the running of an engine away from standard and its clear from personal experience and that of others, that it can have a considerable effect on the engine.
Personally there is way too much speculation in this 'flaw' at present and a strong desire to match a completely different engine against another. Just because you believe that the evo engine should be able to run big power on standards doesn't mean that it will, it has to be seen in its context.The differences in engine makeup don't allow for similar comparisions in my mind, each has to be taken on its own merits.
Its clear from examples on both sides of the equation that you can run reasonable increases in power safely but the window for doing so is very fine. That would be my opinion on it from what i've read and heard and talked about.
Again much is down to the individual, and what they can afford and desire from their car, but whatever route they take it would be best to do it in as correct and proper manner to minimise the risks involved.
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4g63 is far from flawless with standard internals at 400/400 mate!! Just think how fat the X would be with a 4G in there :lol:Not at all.
Try the search button on here and evoM for your answers.
I didnt say it had a flaw, the link was to a thread that says that
But now you mention it,
do you not consider rods through the side of the block a flaw?
or piston ring lands failing due to incorrect gap clearances a flaw?
or valves dropping a flaw?
The block needs resleeving to run big power
Does the 4G63 or 4G64 block need sleeves to run big power?
and yes.... I have experience of a sleeved block and it wasnt a good one :wallbang:
I agree it's not ideal to run sleeves, they can have a whole other load of movement issues, still no choice there, for me anyway, I want 4b11 power!!
I don't blame Mitsi, or even the Hyundai manufactured engine, after all it was made for 300ps, I'd like people to be aware of the risks of mapping the X for 400+ power, there has been a lot of boasting about huge power figures on standard engines, I hope these threads have made some guys stop to think and maybe prevent a catastrophe, just a bit late for me unfortunately, I would 100% do a rod/piston swap and valve springs as a minimum.
I've only seen 2 cases of stock engines popping which any manufacturer can have, not saying it's acceptable, but that's life
The joys of an all new platform It appears to many 4G mappers are now trying to map the 4B the same way. To many EVO-X have completed endurance events to see this event from TTP validated in any way. Same idea with other issues with the
4B ,is having people cry wolf. Better engineers will get the 4B working. People around the globe like AMS,Magnus, TMR etc whom have great engineers will work it out before to long.
Don't think the 4B is not up to scratch! Just try harder!
:thumbup:
4B ,is having people cry wolf. Better engineers will get the 4B working. People around the globe like AMS,Magnus, TMR etc whom have great engineers will work it out before to long.
Don't think the 4B is not up to scratch! Just try harder!
:thumbup:
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Thats the point i was trying to make that they are completely different engines and need different methods. Its not purely down to tuners in my book, manufacturers of aftermarket parts have a lot to answer for as well. Anyone that has seen dyno graphs of various mods on a standard (unmapped) X will tell you the same. Some parts on a standard car are verging on dangerous, others actually smooth out some issues with the car in standard setup. Like others have said its a totally new development, and it will take time to gain a similar level of knowledge that exists for the 4g63's. That won't be gained by scaremongering or running anything down.
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yeah, they could all change the oil ring?
Its always the same with new products, people live in a blame culture and they will contaminate as a cover for lack of engineering talent and mechanical understanding. Good engineers will quickly make the EVO-X smooth reliable and dangerously powerful. A couple of key people(talented engineers)around the globe have already developed EVO X products that I am sure you will see add to the mix. I like to think as a DR! Before I surmise ,I like to inspect and be curious about how things are made.
As I said before, Just try harder!
As I said before, Just try harder!
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you work for who?
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No you dont... its simple in my opinion:It looks like you have to take the 4B11t and create a new engine from it using aftermarket parts
Run sensible fuelling
do not exceed 2bar boost
uprate valve springs to cosworth/kelford etc
tubular manifold
turbo elbow
Fuel pump upgrade
You potentially have an engine there that could happily run 400-500hp.... hardly seems like building a new motor:moon:
with regards to rods it is perfectly viable that some of the 5,000 odd evo x's have a defect which lies in the manufacturing process, thus far there is insufficient evidence of rods being a weakness at street performance levels. Ultimately they have homologated a different design but thats for a different application too. The amount of tuned X's world wide being hammered from pillar to post with stock rods is unbelievable! I can vouch my car made a true 400lbs/ft on TRL's dyno and TD's, my car covered 15,000 miles in this form with a very hard life. Top speed runs/sprints/drag etc. Then you have all the rest ( e.g MATT@TRL'S RS).. its not just luck on my behalf but more like unlucky for those who have broke them.
Anyone with vehicle knowledge knows that various factors can contribute to mechanical failure of a component... ANYONE who decides without inspection of these failed engines and the surrounding ANCILLARIES that they can right off a components integrity is very naive. The rods in the 4b11 are forged and visibly indicate that they are stronger than previous designs used in the 4g63.
I always recommend upgrading the stock fuel pump to a higher capacity item when tuning to 400+… The majority don't!
Overall whilst I agree with your earlier comment that its better to forge the internals there will always be those who push the stock engines to or beyond their limits… I know I would again if given the chance. I may end up being wrong about the rod weakness however I only speak from what I know and the plausibility of the situation in hand.
There's guys who are running massive amounts of power for a stock engine who have had engine failure, believe it or not its not the rod going every time.
Kind regards,
GUM
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