Stock rods needed for testing
 

I have been talking to an aftermarket rod manufacturer that is interested in developing a product for us, AND will take a look at the forces needed to bend the stock rods. We'll get a good idea this way (and comparing this test to other/aftermarket rods) how much torque we're safe for as far as the rods go.

Problem is I don't have enough whole rods for this.

So, I need some complete, unbent rods from people that have upgraded or blew up other cylinders. It is very important that the rods are not bent and that the caps and bolts are included

Please let me know if you have any you can send my way, I am looking for a couple.

The rods will be bent during the testing and will no longer be usable if that wasn't obvious.

Thanks!

i'll see what i can do when i pick mine up. not sure if they were going to keep the block as a turn in or what but i'll ask. i wanted to keep my bent ones anyway to always remind me of what fun its been.

Sounds good, let me know once you find out.

Lex, a local guy here just blew recently i guess. One rod is broken, but the other's may be intact. Not sure if you'd want them, cause they are probably already structurally compromised, but i'll see if i can get them anyway. Maybe your company could do a material analysis on the compound or something.

Would be great to have. Actually, if you can also get bearings and pistons from the motor would be nice to see what they look like. PM me with any more info about the blowup if you have it/can get it. The more info the better.

my engine just got torn apart. i have all 4 good rods. ill swing by the shop tomm. and pick um up. do you need them labled what cylinder they came out of?

this will be very nice to know, good shit lex :bling:

- how exactly are they going to test the rods

im sure they will put them through neumerous compression and torsion tests to basically test their static breaking point. the reason he probs needs alot of rods is because if youu test a sample of say 12 diff rods and they all break at x+/- 20ftlbs of torque, you have alot more realistic results then if you test 3 rods and they all break at x +-40ftlbs of torque.

lol yea, sounds similar to the shit im learning in statistics. sample mean and standard deviation.

-how do they do the testing tho, they put the rods in a engine? or just pull on it with a special machine

actually they hire two gorillas (read gorillas need moneys too you know) and they pull on the rod from each end. then they test how strong the gorilla can pull on a scale and apply x logic to the rod.


lol they pull on it with a machine. we have all these machine at my school but i dont really have the access to use them cause they are more for acedemic purposes.

I can also do tests on rod or pistons and i could pull a rod apart if someone wanted, also test metal hardness's etc
Tensile test a rod anyone?

i think the term is called young modulus where they search how much stress can the rod handle until it strains

yes youngs modulus of elasticity

OK, looks like I have all the rods I need for now. If I need more, will let you guys know.

We will see what these guys can do. I am very interested in what they find because they have terms of comparison with other stock rods and aftermarket ones. Without terms of comparison it's harder to tell what you're looking at even if a machine spits out some numbers.

bf360, if you can do some stress,strain,hardness tests on the rods that would be great. Let me know what you need.

yes i can do all three, just need the actual parts either rods or pistons and i can do the tests

Great, we need a few more rods guys. Get in touch with bf360 and send him a few.

bf360, if you have issues locating some rods let me know, I can send you a couple but I'd rather avoid the to and fro shipping and have someone send you some directly.

ok cool anyone that has any just pm me, as soon as i get them i can do the tests that week

bumping this, get these guys some rods! :banana:

seeing as pistons and cranks tend to not be issues for these motors, are they planning on creating a rod that will be compatible with the factory pistons and crank?

i think overall this is something awesome to have done so we actually know what kinda punishment these rods can take but we also need to understand that rod failure due to sheer power is not whats causing motors to blow. this is something that we really need to push forward on as well. keep up the good work as well alex and billy.

Lex,

Awesome. Just awesome. Can't wait for the results.

any updates on progress? have you guys started doing the testing?

Not yet, will post results when they are available here.

Lex and bf360 way to go guys, keep it up

i still need anything no one has contacted me with any parts

I will see what I have left over and might have something to send you. I live in Canada and shipping to/from the US is really slow.

Im not home to send anymore out :(

Lex i thought you were in washington? what is this about canada?

I live close to the border. I have stuff shipped to WA and drive over to pick stuff up. It's a bit of a hassle because I can only do this at certain times etc.

bump! In for the results :)

this thread is getting my adrenaline pumping. i want results!!!!!!!!!!!1

You know what they say, you show me yours and I'll show you mine :)

LOL nice friendly burn :saevilw:

:)

LEX. im still trying to get my stuff back from the shop as soon as i do ill send it to ya. sorry its taking so long.

someone send Bf360 some. he can test them also right away

I am pretty sure i cant do tension tests of the rods, i do not think the tester has enough power to pull them apart i can do pretty much anything else

well considering the rods never really have any tensile forces acting on them (save for pulling the weight of the piston down) i think this is ok.

The point of the tension test is to determine the strength of the rod not necessarily only how it reacts to tension

Actually tension on the rods goes up with the square of the RPM. So it is equally important to compression. The oscillation between tension and compression is what fatigues the rod.

test them already lex. i'm getting tuned next week hehe

I wish this was my full time job :)

Tension is usually the strongest force on a rod out of all the different cycles.

When its the compression stroke, the exploding combustion helps slow the piston head down and change direction. This takes the load off the road quite a bit.

When it's the intake stroke though, and there's no explosion, That's when the rod alone has to bear the entire force of reversing the piston direction from up to down. This is probably also why our rods let go during shifts, but i'm still confused why it's always low rpm shifts, not high rpm WOT shifts.

I bet i can break one of these rods using my knee, that's how week
they look to me.
Still curious to see the results though, the rods still look cast to me.

The rods break after they have already been bent or twisted. Because they are forged, they are more prone to deforming before outright breaking when overloaded. Once they deform, it doesn't take much for them to further deform or for the piston to snag in the bore regardless of RPM.

It happens during shifts because there is a momentum change and because the crank is moved through the application/release of the clutch further offsetting how forces are applied to the rod. Our rods contact the crank counterweights on either side of the big end.

updates?

I will post them when they are available. In the meantime keep the torque and fueling in check and the shiny side up!

Lex, did you ever get an AP and if so, can you share your map if you made one? With all the knowledge you have shared, I would just like to compare that to the changes you would of made in ATR.

I do have an AP and have great results with it - I can of course share my map and results but I believe most people here wouldn't want to run the settings I am.

This should be in a different thread however.

Thanks :biglaugh:

updates?

Got a little sidetracked on this. I will update when I find something.

In the meantime, I honestly don't think these destructive tests will tells us something we didn't already know.

i think it will personally. i think our rods are much stronger then originally thought

Here's food for thought. Out of the stock rods I have, some are definitely stronger built than others. One is actually a 0.5 mm thicker down the entire shaft with much smoother surface finish. That makes quite a difference.

DJuosteisn i see you viewing this thread go to shoutbox asap

lol, woops. I guess send me a pm if you need.

Now thats a huge deal for more than a few reasons, what is the weight difference between them?

That is not good at all.

Has there been a correlation with build dates and failures? I remember the russians mentioning that they only had rod issues on earlier builds, but not in quite a while. I'll try to find the quote.

Here's one reference to a change in design. This was in regards to whether or not they were having rod issues.

The beefier rod came out of an 07. I have seen 08.5 rods that are back to not being "beefy"

The MS3 and MS6 rods are serialized differently (early versus later builds). The MS6 rods have a 3d bar bode on them probably used for matching weights of rods in each motor.

The MS3 rods only have number/letter markings. I am not sure how to read these serialized numbers but it can be that they are incremental.

I can grab the weight of the rods 06speed6 but I am inclined to think that the rods are matched by weight in a particular engine.

Its too bad that we cant get all 4 rods from an engine.

Regardless, bigger and smaller rods are a big deal...

I wonder if we could get the guys that have had blown engines to weigh their rods in grams and see if its the lighter rods that are breaking.

Generally, production line engines are only static-balanced, matched by weight, some not even that. A GM Malibu V6 likely isn't checked for balance at all, because the engine is mass-produced for low rpm and light loads, typically so, why balance the engine parts to the gram?

Weight is only one factor in strength. Forging tends to produce normalised metal density over the rod more easily than casting, which can be good but, heavier doesn't always mean stronger. The change in reciprocating mass makes a heavier rod put more strain on the rotating assembly than a lighter rod.

Aside from the above, you have the hardening issues that come with forging, since the surface is a machined one, there is often little strengthening of the surface steel through quenching or hammering. This massively affects the potential strength of the rod. Aligning and compressing the grain structure of the steel through work can make a light rod immensely strong. I can't say if these are factors here as I'd need to closely examine the rod and have deep insight into the manufacturing process.

Considering that these rods probably had the same or similar manufacturing processes, I would say weight is a direct indication of strength.

I hope you're not missing my obvious point that a heavier rod NEEDS to be stronger to withstand the added force of it's own increased mass in reciprocation. You can make a lighter rod less strong and be totally fine, due to the decreased recip mass. It's really just a touch more complicated than "heavier = stronger".

do u design engines?

My understanding is that added beef in a non high rpm setup, with the same piston weight, with the same stroke, and with the same metalurgy, will always yield a stronger rod.

Obviously in a cart engine like you are talking about that doesnt apply.

Here is what I mean.

This rod is the "beefy" one.

http://www.mazdaspeedforums.org/foru...g-dsc_0104.jpg

This rod is like all the other ones I have measured (5 others) and it is 0.5mm thinner throughout its entire construction.

http://www.mazdaspeedforums.org/foru...g-dsc_0105.jpg

pull that shit a part lex. i want to know what they can handle

I cant really tell much from those pics except that they appear to have the same finish.

They CAN'T handle detonation. They CAN'T handle boost spikes, low fuel pressure, FFS, uneven meth distribution (the freeze plug idea is terrible), too much timing, too much heat, low oiling.

I can't think of any cars (that were not freak accidents) that have died at anything else but the hands of detonation.

Big pics for full detail

Exhitbit #1. This is what happens when you run meth in the centre of the IM. It only gets to cylinders 2, 3. In this picture you see cylinder 4 which got no meth which has a bent rod (notice the offset spray pattern from the injector on the piston). The piston next to it got all the meth and that's why it's so clean.

http://www.mazdaspeedforums.org/foru...g-dsc_0029.jpg

Exhibit #2. This is the same motor, cylinder #1 that blew. It had a bent rod for a while and it finally broke loose. Cylinder #1 also got little of the meth share.

http://www.mazdaspeedforums.org/foru...g-dsc_0059.jpg

This car was using FFS and experimenting with leaner A/F ratios using meth - except that poor #1, and #4 were not seeing much meth at all!

Pointing out difference in shaft width. Look at the calipers. They are opened and locked the same amount in both pictures.

lex is spraying meth in the intercooler pipe right before the throttle body the best?

Unless you do each runner yes, spray it where the full airstream can come into contact with it.

awesome pics!

yeah that freeze plug idea was terrible i cant believe so many liked the idea.

and yes 18psi thats probably the best idea other than one in each runner etc. if you have the nozzle far enough away from the IM then it should have time to mix pretty evenly thruout the air

Great pics lex, worth the wait for the page to load, lol. Also good info as well.

More food for thought:

From SAE international:

It was found that methanol fuel is more susceptible to pre-ignition compared to gasoline fuel ... Platinum tipped spark plugs were found to be highly susceptible to pre-ignition with methanol fuel.

Pre-ignition and detonation tendency increase with the increase of engine load, compression ratio, inlet air temperature, advancing the ignition timing and lowering the engine speed

The discrepancies in size between the rods is most likely because of the forging process not everything will come out the exact same when forging.

Link to document?

If i recall correctly, methanol has a much higher autoignition temp than gasoline so I would expect it to be less prone under similar circumstances.

bahahah... Im not even going to say anything.

You are correct, gasoline has an autoignition temperature of 280 C whereas methyl alcohol has a temperature of 365 C. There is more to it than this however. I would suspect this to really become an issue when a large percentage of the fueling is done by methanol.

The abstract states:

Here is the link to the paper: Pre-Ignition Phemomena of Methanol Fuel (M85) By the Post-Ignition Technique

I just want to say I appreciate the info shared on the thread.

Here's something else to avoid. This car blew as it was being loaded (foot to floor) from a low RPM. Bent rod but not through the block. It happened right as KR hit 6.0.

http://i47.photobucket.com/albums/f1...2746/boom2.jpg

So would a different type of plug help. ie copper? Sounds like similar problems that nitrous causes. Im new to the whole meth thing so take this with a handfull of salt.

@lex
Could you post the graph itself iso a printscreen, its hard to read. AFR's look pretty high for a WOT run imo?

That's all I have - it's posted on this forum from a member speed_3.

i was under the impression that platinum plugs were a no-no in boosted applications.... copper or iridium. and no one makes copper plugs that works for us (that i know of), so that kinda narrows it down..

i did run plat plugs for a short while while waiting to get some new step colder ones..worked fine for a few days

I have built up a few engines in 25+ years of doing this hobby both import and domestic.

I agree that a huge difference between the two rods of supposedly the same spec. This looks far beyond manufacturing tolerances and more like a redesign or different vendor suppying the rods and getting the spec wrong or altering it for other reasons. However, I'll repeat, a heavier rod, especially in a high rpm app, needs to be stronger to withstand the forces it's greater mass imposes. Something is up, here.

Now, no rod is going to take for long the carnage I'm seeing evidence of here, we have shattered crown edges near the ring lands, signs of possible hydrolock, etc. I can't tell too much with this shitty comp but, these are showing signs of serious abuse and suggest that the recip assembly is being stressed light-years beyond design.

There's an engineering safety margin built into all engine parts and cost has forced engineers to whittle away at that margin. So, cars with engines like my 5.0, which could easily take 50% more power than stock without breaking anything are gonzo like the dodo these days.

Just to clarify, the crown is smashed up like that because once the rod let go, the piston was driven into the head. The markings are essentially an imprint of the head on the piston crown.

I will get more pics up - but the bottom of the piston is scraped up by contact with the crank while it was still attached to the bent rod. Essentially, something bent the rod first and rod broke afterwards.

There is another rod (#4) that is also bent in this motor and was running like this for a while as well.

So the question remains - what is causing the rod to bent in the first place.

IMO the biggest cause is detonation or pre-ignition and excessive load at low engine speeds. Essentially excessive, uncontrolled cylinder pressure.

I know oil hydrolock has been discussed but I find that hard to believe. Based on how easily the motor knocks stock and when hot (for example), I am not surprised it is so sensitive to knock when the boost is turned up.

Remember that fuel starts to be injected and mix with air only after the intake valves have opened. There is no premixing that happens behind the intake valves in a port injected engine.

I'm still unsure if fuel which is not properly mixed and combusted, can pull heat out of the cylinder.

Also, excessive, uncontrolled cylinder pressure would greatly increase temps. If the volume isn't increasing (slow rpm), but the pressure is (combustion), the temp must also.

Or in an even worse scenario, volume is decreasing (with either detonation or spark advance of >50), with pressure increasing.

I know light load KR isn't something to necessarily worry about, but it may be a valid indication of how high the temps may be getting. My stock timing maps were above 60 at it's lightest loads (idle) between like 1500-3500rpm (i'll have to verify by looking at a map, bu you get the idea). No wonder i see knock after sitting at a light for a couple minutes, then get on the gas and start to load the engine. Same probably goes for highway cruising.

I also wanted to ask if anyone knew the rod length to stroke ratio for our motor.

From what i've read, it gives a good indication of the likelihood of seized pistons with variations in crank alignment and probably bent rods.

To tell you the truth, I don't see the classical scuffing associated with seized pistons due to piston expansion. They all seem to seize because they are crooked in the bore.

To throw fuel on the fire - here's more about alcohol tendency for pre-ignition:

Source: System and Method to Control Pre-Ignition in an Internal Combustion Engine - Patent application

Pre-ignition kills instantly......Detonation kills over time, and the higher the HP per displacement the shorter amount of time it will take detonation to show it's ugly head.

so are you saying meth is hurting us?

Lex made the statement that meth is more prone to pre-ignition than gas, so if there is a pre-ignition source in the combustion chamber, then yes, the potential for a pre-ignition event is more likely when using meth or an alcohol based fuel. To me that is why it was so important to make sure that there is no way for oil to be induced into the combustion chamber, and use the coldest plugs that would be feasible to run the car on.

it sounds like 100% meth might...

Meth is the only alcohol fuel out there. And i'm not sure whether or not Lex's quotes are in reference to "meth". For all we know it could be talking about e85.

But i agree, if it does apply, it should be taken into consideration before squirting it into your engine.



I believe if meth was horribly flawed in terms of pre-ignition, it probably wouldn't be such a popular solution in motorsports.

But if indeed the above quotes refer also to methyl alcohol, and if indeed our cylinder temps are getting hotter than other engines, i could see it being a problem.

Personally though, it's done wonders for my car, though i only run a 50/50 mix.

No. Lex mentioned that Methanol is more susceptible to detonation with PLATINUM tipped plugs. Our upgrade that a lot of people run (denso) are iridium tipped...so that doesn't really apply to us.

But what IS possible hurting us when it comes to methanol, is the PTP Freeze Plug location.

PTP claims it was equal spraying through all cylinders...and I beleive it when they did their testing when the intake manifold was off the car, but its a whole different ball game when you have pressurized air inside the manifold.

And from Lex's findings, it seems that cylinder 1 and 4 are getting a lot less methanol then cylinders 2 and 3...thus...why cylinder 1 blew.

From Lex's discoveries...Id suggest anyone with PTPs freeze plug nozzle to turn off their meth/run a more conservative tune. I know I turned off mine and added fuel so Im seeing mid/high 11s without Meth. Im going to see if I can get my methanol plug tapped into my cold pipe.

p.s. the pictures of the pistons is from my car.

Methanol alcohol is more prone to pre-ignition on a hot surface than gasoline. Of course this greatly depends on the amount of methanol present, hot surfaces present (spark plugs, piston tops, deposits), intake temperature etc.

I'd stick to a 50/50 mix to simply cool intake charge.

The graph below is self explanatory. It shows that alcohol fuels ignite at lower temperatures than gasoline.

At the same TIME, alcohol has a much higher knock threshold. They are 2 different properties.

http://www.mazdaspeedforums.org/foru...mperatures.jpg

We got to stop using as added fuel, and get the tune straight.

bahaha ive been saying meth was crap for years. Vindication at last!

Detonation is pre=ignition.

Ghetto motorsports, if it was so good you would see it in NHRA, Indy, and Nascar.

Ide bet if someone showed up with a meth tuned engine to Engine Masters they would be laughed out.

from what I'm reading, anything but 100% meth should be fine...but what about the need to run a colder plug? with meth and higher pressures, wouldn't ITV24's be needed/necessary?

I'm more a fan of the water injection, not necessarily meth. I don't like meth. I think it's a horrible fuel, and dangerous if inhaled. All the books i've read shy away from it as a fuel, and say there are far better alcohol fuels like toulene.

Water injection was huge in WWII, and allowed engines do some unbelievable shit. I'm a fan of a cool combustion chamber, and water does exactly that.

Please do not confuse detonation with pre-ignition.....two totally different events that cause different outcomes on engine failures.

Detonation is the spontaneous combustion of the end-gas (remaining fuel/air mixture) in the chamber. It always occurs after normal combustion is initiated by the spark plug. The initial combustion at the spark plug is followed by a normal combustion burn. For some reason, likely heat and pressure, the end gas in the chamber spontaneously combusts. The key point here is that detonation occurs after you have initiated the normal combustion with the spark plug.

Pre-ignition is defined as the ignition of the mixture prior to the spark plug firing. Anytime something causes the mixture in the chamber to ignite prior to the spark plug event it is classified as pre-ignition. The two are completely different and abnormal phenomenon.

Source: Detonation and Pre-Ignition
by Allen W. Cline
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