Aftermarket rods & stock pistons

Just seems moody when cold, not sure how to describe it. Same as the when the car had stock motor but more so.

So is it making a strange sound? Does it feel rough? I'm trying to understand you I really am lol

I think I understand what he's saying. Last winter when I would get up for work I'd hop in my car and drive immediately. Until it got up to operating temp everything just felt sluggish and not as it did when fully warm.


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Just seems moody when cold, not sure how to describe it. Same as the when the car had stock motor but more so.
I would attribute it to the tune pulling timing while coolant temp is below "xx" degrees.

@Realgib3 can probably confirm with my car. But when I was stock block, I could drive the car under 130* coolant temp, but it wouldn't run very well. Just very sluggish.

Now that I'm on a built motor, if I even try to drive anywhere before the coolant temp hits 140*, it's damn near undriveable. 140* is the sweet spot where everything goes into place on my car. I could try pulling down my road while coolant temp is 136* and the car struggles and bucks back and forth, and just drives like crap, but as soon as temp hits 140*, it's like a flip is switched and car drives perfect.
[doublepost=1482959843][/doublepost]
I got confused by the fact all of your statement is in quotes. Your 4032/bearing statement confused me. Derp...

Anyways, pretty sure same guy, Mark Gibson, said keyed crank and pinned cams also aren't necessary @ 500 whp for us, according to a great deal of his practical experience. Aftermarket cams aren't needed either (and weren't used in many - if any - of his builds, that I know of). Many of them were entirely stock block. I guess we're just blessed.

May be much more to 500whp for other platforms, but Speeds are good in this regard. YMMV, but I trust him. He's a Speed OG and has a LOT of practical experience under his belt, both in building and tuning. Have you read this thread yet, BTW? http://mazdaspeeds.org/index.php?threads/open-tuning-turbo-theory-discussion.3332/

A lot of practical experience has shown that not only are stock headstuds able to handle 500whp just fine, but so are the bearings and frictions washers... Again, the key is alky. I'll see no detonation at all with 40%+ fueling volume coming from alky-based fuels. I'll also run an AFR-based failsafe set to trigger my Guardian Angel if the alky stops spraying, and it reacts in like a tenth a second (very quick failsafe). Here's another knowledge drop of Mark's: http://mazdaspeeds.org/index.php?threads/my-view-on-head-studs-for-the-mzr.3346/#post-27326

I feel 100% confident I'll never have any knock. I've done a TON of tuning/experimenting with just in-tank eth and was able to go to 22-degrees timing and still have zero knock, and that was pushing the snot out of my K04. With a much bigger turbo running in the fat of its efficiency range and a crapton more alky on top with my WMI system IN ADDITION to my in-tank eth, it knocking is a chemical impossibility, unless some mechanical issue is present. Heck, with an EFR7163, I won't need the timing or boost levels that foster knock easily anyways, crapton of alky notwithstanding.

Maybe @Sho can chime in here, too.

H beams, standard Manley wrist pins, 88mm Manley platinum series pistons (2618), oem bearings (main and rods) , no Keyed crank, and oem head studs.

53k+ miles so far. The first 38k seeing 28-30 psi and 16* up top on a 5862, and the last 15k at 35psi and 18* on the same turbo. Boost curve is progressive to keep torque down. E23 mix in the tank, and spraying 2000cc min of 100% meth.

Here's compression test that was done not too long ago
 
I would attribute it to the tune pulling timing while coolant temp is below "xx" degrees.

@Realgib3 can probably confirm with my car. But when I was stock block, I could drive the car under 130* coolant temp, but it wouldn't run very well. Just very sluggish.

Now that I'm on a built motor, if I even try to drive anywhere before the coolant temp hits 140*, it's damn near undriveable. 140* is the sweet spot where everything goes into place on my car. I could try pulling down my road while coolant temp is 136* and the car struggles and bucks back and forth, and just drives like crap, but as soon as temp hits 140*, it's like a flip is switched and car drives perfect.
[doublepost=1482959843][/doublepost]

H beams, standard Manley wrist pins, 88mm Manley platinum series pistons (2618), oem bearings (main and rods) , no Keyed crank, and oem head studs.

53k+ miles so far. The first 38k seeing 28-30 psi and 16* up top on a 5862, and the last 15k at 35psi and 18* on the same turbo. Boost curve is progressive to keep torque down. E23 mix in the tank, and spraying 2000cc min of 100% meth.

Here's compression test that was done not too long ago

I also feel as though the sluggishness comes from the fact that your car is pulling less vac and technically has less compression when cold on a built motor since the pistons are contracted.
 
I also feel as though the sluggishness comes from the fact that your car is pulling less vac and technically has less compression when cold on a built motor since the pistons are contracted.
Yes that too. I don't typically see full vacuum at idle til the car is above 160*
 
I would attribute it to the tune pulling timing while coolant temp is below "xx" degrees.

@Realgib3 can probably confirm with my car. But when I was stock block, I could drive the car under 130* coolant temp, but it wouldn't run very well. Just very sluggish.

Now that I'm on a built motor, if I even try to drive anywhere before the coolant temp hits 140*, it's damn near undriveable. 140* is the sweet spot where everything goes into place on my car. I could try pulling down my road while coolant temp is 136* and the car struggles and bucks back and forth, and just drives like crap, but as soon as temp hits 140*, it's like a flip is switched and car drives perfect.
[doublepost=1482959843][/doublepost]

H beams, standard Manley wrist pins, 88mm Manley platinum series pistons (2618), oem bearings (main and rods) , no Keyed crank, and oem head studs.

53k+ miles so far. The first 38k seeing 28-30 psi and 16* up top on a 5862, and the last 15k at 35psi and 18* on the same turbo. Boost curve is progressive to keep torque down. E23 mix in the tank, and spraying 2000cc min of 100% meth.

Here's compression test that was done not too long ago
EXCELLENT compression. Stock CR? If not, I wanna use that honey badger tester, LOL ;)
 
Yes that too. I don't typically see full vacuum at idle til the car is above 160*

Mine runs like shit too till about 150-160 degrees but I pull 21-22 inch of vacuum as low as 120 degrees after it comes off fast idle.

I always let the car hit at least 120 before I start driving and I never beat on it or get into too much boost till I know the oil is somewhat warmed up.

With 2618s the most wear will happen during warm up so it's very important to let the motor get warmed up good before loading it and don't just rely on coolant temperature, the oil needs to be good and warm too.
 
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@Redline; any of the companies you reached out to give you a response yet?
Nope, not yet. I think they're all on holiday vacation, LOL. Don't worry; I'm extremely persistent. Numerous emails will be sent, and then I'll move to the numerous phone calls, if necessary.
 
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@Redline; any of the companies you reached out to give you a response yet?
@broda @WetzMS3 @Mauro_Penguin @davychronic

Here you go: straight from a Mahle piston engineer who worked specifically on our 4032s for SP63:

"Zack,

I worked with Speed Performance on the design of these parts. The 425whp rating is conservative. I would recommend the 4032 for your application at 500whp and using methanol / alcohol. The 2618 would give you a higher safety factor but as you stated the life span of the part is less.

The 2618 part should be approximately 10g heavier at the same bore size.

Kind regards,
Justin Dossett
MAHLE Engine Components USA, Inc.
MAHLE Motorsports (IMO7)"

So in other words, he's saying exactly what I was saying and @Realgib3 was saying: since I'll be using so much alky, the 4032s would be perfectly fine for me, and offer numerous other benefits as well, including longer service life, lighter weight, tighter PWC (so less chance of ovaling), faster warming up/ready to drive, more DD-friendly, less chance of burning oil, etc. @g00s3y just has to decide on his whp goals, and if/what amount of alky he'll run (if it's even necessary for his power goals).

I'll update as more piston manufacturers weigh in too. But in my eyes, this guy's view is really the final word on the matter. The 4032s are, after all, from Mahle; from him and his design team.

Edit: I also posted this in my personal 4032 thread that I started a while back because it's relevant.
 
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More info from our Mahle 4032 Piston engineer:

"Zack,

Piston to wall clearance should be 0.0020" for the 4032.

Top ring gap 0.021"-0.024"
2nd ring gap 0.017"-0.024"

Kind regards,
Justin Dossett

MAHLE Engine Components USA, Inc.

MAHLE Motorsports (IMO7)"

Since we normally run a smaller top gap, and slightly larger bottom, I asked him if 0.021" (top) and 0.023" (bottom) would be good for my goals. We'll see what's what. The general Mazdaspeed practice is to have smaller/larger top/bottom gaps. These 4032s may be game-changers in this regard. Any engine builders on here want to speculate/reason about how this would apply with these pistons?
[doublepost=1483638709][/doublepost]Response

Me:
"Justin,

Gotcha. You've been so kind to entertain my responses. Just one more quick question: is there a certain specific ring-end gap you'd recommend for 500whp and ~40% fueling from ethanol methanol? Folks with my platform have had a TON of luck running a slightly smaller top end-gap. I think it had something to do with combustion gasses not getting trapped, but I don't remember for sure. Anyways, what about maybe:

0.021" top
0.023" bottom?

Does that sound about right for me?"

Justin @ Mahle:
"That will work yes and will be safe.

There are several thoughts behind staggering top and second ring gap. You will see conflicting arguments but piston design and application are the two largest drivers.

On the piston design side, the driver is whether is has an accumulator groove on the land between the top and second ring. The groove acts as a reservoir for gasses that get past the top ring. Having the extra volume between the rings reduces the pressure that could potentially unseat the top ring. The majority of our pistons have an accumulator groove (The ones you are selecting do). Without the groove, the second ring gap needs to be larger so that gasses escaping past the top ring have a leak path so pressure will not build between the top and second ring.

Heat is another factor in selecting ring gaps. The top ring sees significantly more heat than the second so the amount the running gap reduces will be less on the top due to the differential in heat. So if you run the same ring gap on top and second, while the engine is running, the second will have a larger gap.

Hope this helps."
 
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I run 0.020 top and 0.022 bottom on my Manley's... Hmm.


Then again, I'm no engine builder lol.
 
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I like that he didn't just confirm that your suggested gaps would work safely, but also explained the logic behind staggering the sizes. I'm sure that not everyone would have taken the time to do that, rather than just send back a quick "yep, that'll work."
 
I like that he didn't just confirm that your suggested gaps would work safely, but also explained the logic behind staggering the sizes. I'm sure that not everyone would have taken the time to do that, rather than just send back a quick "yep, that'll work."
Yeah, I talked to him on the phone, too. He said he'd personally run 0.021" top and bottom, which would effectively be a smaller gap up top due to the much higher heat that it sees. This means the top gap would close more, and the bottom gap wouldn't close as much, so when the car is fully warmed up, the gaps that started the same at 0.021" for both would be smaller on the top ring and larger on the second ring. These pistons have gas pockets to prevent the building up of pressure that could unseat the top ring, etc., too, so they really are a great design.

I also like how he actually deferred to SP63 because that's where the rubber meets the road. They're building actually building these engines, and we all know that actual practical experience >>> pure theory. SP63 said that they may vary the ring gap some based upon if the cylinder had a little bit of taper, and/or other issues, which sometimes occur. A perfectly machined block down to the ten-thousandth of an inch doesn't happen 100% of the time, and when this is the case, the proper ring gaps can be impacted.
 
Not to beat an old horse to death, but I am building an engine that I want to use the stock pistons with a set of Eagle rods. I was just wondering if anyone has seen an article or knows what needs to be "trimed" on an aftermarket rod.
 
Not to beat an old horse to death, but I am building an engine that I want to use the stock pistons with a set of Eagle rods. I was just wondering if anyone has seen an article or knows what needs to be "trimed" on an aftermarket rod.

Some of most of it but not all maybe just a little but could be a lot depends on if some is not enough then you may need to take a little more then a lot.
 
Not to beat an old horse to death, but I am building an engine that I want to use the stock pistons with a set of Eagle rods. I was just wondering if anyone has seen an article or knows what needs to be "trimed" on an aftermarket rod.

If you buy aftermarket rods with the correct wrist pin diameter (they do exist) then you won`t have to shave/polish/hone anything. It`s not a common idea but not a terrible one.
 
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I guess I’ll put this here sense we were talking about alloys too.

Just hit 30,000 miles on my bottom end and got my first piston slappy slappy this morning. 2618’s. Mind you this is a pop n drop so it wasn’t exactly torque plated and properly honed, just used a dingleberry and brush, but they were round, straight and PWC was spot on, just the cross hatch wasn’t the best lol
 
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I guess I'll update as well. Nearing 69k om my Manley Rods and pistons. Still no piston slap on cold start. Haven't done a compression test in a while, but the car still pulls hard.

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