Rods for OEM pistons - No Machining Required
 

Can anyone confirm which rods will fit OEM pistons [ taper already machined into the small end] with no machining required?

Ive heard some Carrillo rods will fit but does anyone have a P/N. There are about 4-5 different versions for our platform.



@06Speed6;
@superskaterxes;
@SPEED6 KILLAH;
@Tomas;
@atvfreek;

thanks

I have order a couple Carrillo H beam rods with the oem taper on it. Basically who ever order them will have to let them know that you want the oem taper on it.

Rods for OEM pistons - No Machining Required
 

Does anyone have pictures of this taper? I've never noticed it when looking at pictures of our rods/pistons.

O I C Thanks Pablo!

although that sucks as far as timeframe is concerned...oh well. Depending on their lead time I may just order K1s and have them machined.

You can order both the A and H beams from Carillo to fit the OEM pistons.

roger that but I want this done sooner rather than later. I can just imagine a 1 month lead time from Carrillo which I would rather not wait for. and or added cost for the custom order.

I do want to build the motor complete before I tear my car down so I'll just order another set of K1s and have them machined here locally and compare the estimated lead times for both...or just use my bench grinder and do it myself :)

you can get an idea buy going to Carrillo's site and look at their taper options. The top of the small end is tapered to fit into the narrowing portion of the pin bore of the piston.

Call them before assuming the lead time.

oh absolutely...

edge is working it from their end...I'll make a direct call tomorrow.

Also I have learned this the hard way many times. Do it once, do it right even if it takes longer.

You can have any machine shop machine the tapper on the rods.
Carillo is the only one afaik that will sell them to you with tapper on request.
On K1 rods I would not recommend machining the small ends. They are fairly thin. eagle rods have a lot more, and IMO, sufficient material.
It's really a simple process to do it yourself with a high speed air grinder using a round 2" attachment. You only need to take about 1.5mm on each side. IMO the reworked small ends on the Eagle rods should still be stronger than the thin walled K1 rods even if shorter in length.
I did this on eagle rods with Pu pistons. You need to oscilate the rods back and forth on the piston with the wrist pin through it to make sure there is no interference.

Stock rod compared to K1

http://i1211.photobucket.com/albums/...photo-25-1.jpg

Reworked Eagle rod in piston with standard eagle rod on top.

http://i1211.photobucket.com/albums/...psde089252.jpg

Dan, since you're taking all this apart consider cryo treating the pistons. It does improve the material strength.

@Tomas; Thanks for your insight...when "machining" the Eagles, did you balance them during the process with that grinding? How did you debur the bearing surface?

With the Carrillo rod are you just ordering their standard taper or is it MZR DISI specific.


@SPEED6 KILLAH;


Anyone?

ok what about a swain tech coating on the tops as well? I seem to remember this is a topic of debate.

w.r.t ceramic coating engine parts, piston tops are by far the best place to start.

Also a good idea on the coating as it acts as an insulator to the piston crown. I didn't believe in cryo treating until I spoke with people that do circle track racing and must use OEM components. They make the rods and pistons last and take more abuse with cryo treatment.

looks like for $40 [10 per piston] you can get them nitrofreezed but the minimum order is $50 so 50 plus shipping from them.

Engines | NitroFreeze Cryogenic Services & Solutions, Worcester, Massachusetts

they say pistons and rings...not sure about the rings...thoughts?

good insurance policy if nothing else.

I also have Eagle rods machined in the local shop, and they are still going strong after 1 year and 15k miles.

I'm not sure why most of guys choose K1 over Eagle.
Eagle seems to be more beefy..

swain tech TBC top only is 27 per piston.

Automotive Coatings Price Sheet | Swain Tech Coatings | Industrial Coatings | High Performance Racing Coatings

I wouldn't remove the rings - send them assembled. The things that get destroyed in cryo are seals/gaskets otherwise people would just drop entire engines in.

so lets stir the pot a bit and see if we can compare/contrast the benefits of each process, ceramic coating the tops or cyro dipping. if this has already been discussed here please link to the thread(s)

If you could chose only one which would be more beneficial?

Costs of each are obvious with ceramic costing ~ 2x as much.

cyro strengthens the entire piston which protects it from stress, including heat stress.

ceramic coating the tops reduces the heat the piston will see and may reduce overall block temps by reflecting the heatsoak the piston receives and transfers to the cylinder walls via the rings. i.e. a heat management mod of sorts.

IIRC @BlueStreak; coated his piston tops and perhaps could shed some light on this option.

@Lex; your thoughts as well.

discuss.

Competition Automotive (our local machine shop) says ceramic coating the piston tops is the best place to start w.r.t. ceramic coating engine parts. Other than that, I can't compare ceramic vs. cryo.

I will be swinging by there tomorrow to drop off some diesel engine bits (they're rebuilding an engine from a Case 410 SkidSteer of ours) so I can ask what they think about cryo vs. ceramic.

I'd defer to Lex for more info.

ok I think I should strike the 27 per piston for Swain Tech. For turbo/nitros they recommend their "gold coat" which is ~43 per piston.

I suppose you could argue that with E85 + meth the more durable coating may not be required but IDK. Yet another can of worms opened it seems...lol

I will not go with that coating for sure so it is looking like cryo or the TBC coating at most.

I'll head over no NASOIC to see what those guys do..I know they use Swain Tech quite a bit.

http://www.mazdaspeedforums.org/foru...pgraded-98445/

for those who want pictures, see post #18

Rods for OEM pistons - No Machining Required
 

You should stick with the manufacturers guidelines on something like that, IMO. You don't want to risk that coating breaking up over time and ending up in the turbine wheel. I imagine that wouldn't be very good for it.

Yes, I did tighten up the weight difference between rods while grinding down the small ends. The stock variance on the Eagles was less than 0.8g however.
For deburring the edges of the brass bushing in the small end I just took a needle file and after that a 400 grit paper. It really just needs very light deburring. You don't want to file a bevel onto the bushing.

I am gonna have to go against Alex on the cryo treatment. From my research and talking to people in the metallurgical industry it's all bogus. That's why you don't see any industrial applications of the stuff that I know of. We deal with fairly exotic aluminum, titanium and steel alloys here at work and cryo treatment has never been considered an option. Shot peening and WPC treatments on the other hand have a pretty good track record of increasing material strength. Shot peening is good and WPC even better. The joint for WPC treatments here in the U.S. is run by some Japanese guys. I was originally going to send the Pu pistons for treatment but then I said meh.

right on...but I am tired of fail and trying to make things work...LSS...Carrillo H beams ordered today with taper. 2 weeks out at most..:fingersx:

now on to potential piston treatment...

I am NOT paying 43 bones per piston for ceramic coating for a DD 425-450WHP motor. I think that is just throwing money away.

I think the OEM pistons as they ship will suffice with proper heat management but time will tell if I am wrong.

cryo treatment is the only other option and until today I had never considered it. I am interested to see if Lex has anything to add to his recommendation or if anyone else has any input.

my block will be here mid week next week so I can ship pistons out at the end of the week. This is the time I allot myself to make a decision.

Sorry for not contributing, but

I am extremely happy with my Pauter rods, the tolerances are very good, balance is fantastic and the bushing is beef so I had no problem opening it up for 22.5mm pins.

Cryo is very seductive, I believed the hype for a while but I am against it now. *IF* the temp was within a few millionths of 0 kelvin then maybe possibly, but the physics is against even distribution and crystalline type molecular structure once the piece heats up so unless the part is physically collapsed into a crystalline structure through pressure or lab temperatures then it wont hold the form and it isnt worth the money. Its the same reason that room temp and high temp super conductors dont exist and its effectively what they are selling.

Ceramic coating pistons, im calling snake oil again in all but the most extreme applications. Its not that it doesnt work, its that ceramic is designed to reject sustained temps and the chamber is not sustained temps. The chamber goes from 200*F to 1800*F and it has liquid fuel being sprayed into it and aluminum melts at FAR less than 1800*F so the actual sustained chamber temp is simply not high enough to detonate naturally. If the mix is tuned far to the extreme, it can be made to detonate. Ceramic coating is not needed short of nitro meth.

I have zero taper on my rod bushings, please educate me on why an uneven bushing is beneficial.

God have mercy, oem pistons at 450whp. Evil Kinevil would be proud. You know as well as I do that you wont stay at 450whp, upgrade that shit, ain't nobody got time fo that.

This is what happens when you don't do your own research and im guilty of this with respect to cryo treatment. I would trust Tomas as he works in the industry and will look more into this myself. The guy I was speaking with had hands on racing experience and I didn't look into it further. He was treating steel connecting rods and not pistons however. Sometimes people correlate the wrong things and this could certainly be the case. Lesson to learn here don't trust anyone and do your homework. Now it's time for bed.

Oh and the tapered bushings are that way to reduce friction losses on the unloaded side of that bushing.

Looked into this very briefly and it appears cryo treatments are effective on steels and not aluminum. Perhaps this is why you haven't heard about it Tomas?

I dont trust wiki either because its hard to know who wrote it and what their qualifications are.

Lol yeah. That could be why I have never heard of cryo treating aluminum alloys.

But even on steels, the results are very questionable. I have heard the same thing you have from week end racers about how great cryo treatment is on brake rotors, which IMO, is an even bigger waste of money than engine components. Sames applies to clutch PP's etc.

You need a tapper on aftermarket rods so they will fit in stock pistons. Just like the stock rods do.
The tapper is not needed with wiseco and the other pistons.

Haha my bad, I thought you guys were tapering the inside of the bushing and I was thinging wtf

The outside of the small end does need some work.

lol

well we will see. I think I'll likely land around ~425WHP. I look at it this way..my motor will see 400+ HP runs .01% of its life. Those runs are for ~10 seconds at a time. I've had the car since 2007 and never been to a track so it is unlikely I'll pick up the habit now. FWIW cld12pk is around 450+WHP on a completely stock motor. Probably won't last 100k miles like that but again IMO the amount of time you spend at that HP level calculates into longevity.

this intended use of the motor coupled with the fact I am getting a brand new LB and don't want to hone the bores P2W out for forged pistons dictates my planed approach.

If I don't want to stay at ~400 WHP for long....well I have another complete motor waiting to be built.

Sooooo the OEM pistons will go back in as they are, no treatments applied.

thanks for all the input guys!

Dano, aftermarket pistons are set up for a standard bore. With the larger P2W clearance, the pistons are smaller. Neither silvapain, nor I, had to hone/bore to fit ours with a .0035" clearance. The bore is also ready to go from the factory.

Can you explain why my motor with 55k miles on it had P2W clearance of .0005 to .0010 in places, average was around .0020-.0025 so I had to hone the chit out of it to make it fit?

I guess I will find out when I pull things apart but I was planning to completely build the SB of the new motor before pulling my current motor. :thinking:

edit:

before honing - delta to Wiseco's - coating NOT included in piston measurement.

http://mail.netsecurenow.com/img/bui...es-prehone.jpg

Did a bit more looking into cryo treatments of steel (and yes they apply to steel).

The hardest crystalline structure for steel is called Martensite and this refers to the crystalline structure of the metal. When steel is heated past ~1650*F austenization occurs which means its structure starts to internally change and turn to austenite which is not as hard as the martensite structure.

When it is cooled back down the crystalline structure may still contain austenite which is a source of weakness, cracking in the steel structure.

What has been shown is that in certain steels, dropping them very low in temperature for a certain amount of time (lower and longer the better) transforms the weaker austenite structure to martensite and improves the hardness of the steel.

This is where cryo treating has evolved from and it does work, but it has to be done properly and to the proper materials - not aluminum and only certain steels. Where cryo treating probably got its bad name from is from small businesses promising the world and applying the treatment to incorrect materials or using incorrect procedures.

Read a bit more here:
http://www.v-research.at/aktuelles/p...bilization.pdf

Why did I go to college? I could have just subbed every one of your posts and paid you half of what I paid for my degree. :wink1:

So by using and treating the OEM pistons with aftermarket rods, one can avoid many of the disadvantages of forged pistons, correct?

No the oem pistons are aluminum thus cryo doesnt help

apparently not proven to work on AL.

edit: bunny beat me to it

No.
Cryo is not for aluminum.
Cryo for rods is possible but not needed.

As far as effectiveness of cryo we won't solve that here.

For reference these are the WPC prices from an email about a year ago.
If you are set on treating the OEM pistons WPC is IMO the way to go.

******************************

Thanks for the info @Tomas;. That's good shit right there. Treated synchros... :scratchchin: