New motor install options
 

I have been doing some thinking about the pending 2nd build and thought I should put a poll together to get some opinions. The history of how I got here can be found in the below thread but if you don't already know it, you prab don't want to read for days to get caught up...lol

http://www.mazdaspeedforums.org/foru...ml#post1693054

So I have settled on getting a brand new Longblock from Mazda. Beyond that is where things get a bit fuzzy.

Option I:

Acquire LB, crack it open, measure and hone bores to fit my existing Wisecos [ I am 90% sure P2W will not be sufficient to install them judging from my existing block's measurements], thoroughly clean/have the block cleaned, then assemble as normal. This would of course require complete disassembly of the entire shortblock and this time around I would either borrow a deck plate or purchase my own. This is way more work than I want to do TBH.

Option II:

Acquire LB, crack it open, only open up the top ring gap on the OEM pistons, reassemble with no muss or fuss. This would be part of the Heat Management / saving the OEM internals experiment. The possible problem with the validity of the experiment is the new motor will have PU pistons in it and it might just be that Mazda has already corrected the broken ringland failure potential with the new design. My overall goal is 400-450 WHP and I have no issues keeping TQ below 400-380 b/c FWD so really I don't need a forged motor or am right on the bubble.

Option III:

Acquire LB, install it as is, perform a partial demod, sell car. Although if going this route a salvage motor is a better option...lol


If I went with option II, I still have a spare motor that I can build full tilt in my own sweet time over next winter or the one after that or never. it is going to be easy for everyone to vote option I cuz they are on the interwebz and things happen instantly. In real life that process will be weeks to a month in the making. Option II is literally a weekend job.

Tearing a new LB apart invites to a lot of unforeseen issues. Touch it as less as possible but enough to make it hold the power and torque you aim for.
Personally I'd go for option #2 + forged rods. Just don't hone it for the forged pistons, not yet at least, it will hold this power for a decent amount of time as is.

I vote option 2.

Get a machine shop to bore it. Shouldn't be expensive.

+1 on this opinion too!

Option 2
Check the gaps and put er in... I would think long and hard about going option #1 .. The amount of work Vs your goals is hard to justify..

That still leaves you with your existing block to part out or pull to figure out the noises/fail u were having :)

In the end the time is a factor and being down for month sounds like a bad time

.02

Option 2 + stronger rods (just in case). This is what I have been preaching all along.

I would even say Option 3 without the demodding and enjoy a 400whp car with a fresh motor. The ring gap is not the confirmed failure mode remember. Get a bigger rad to keep the new motor cooler with the money and hassle you save and enjoy the car.

+1. Pu pistons plus forged rods.

Can you separate the OEM pistons from the rods safely?

I was under the impression they were press fit?

+2 I think if you can keep the rods from breaking and punching a hole in the block you can have a very fast and reliable car.

Let's not forget the reason he's suffered so much: it was the cursed piston.

The wrist pins are held in with circlips. They come apart easily.

Thanks. I just tossed my pistons and rods when I got my spare motor and never checked.

True. But the new motor will have the Pu pistons I'm assuming.

Rod swap only is an excellent compromise idea.

Is it only the ~$800 Carrillo rods that will fit onto OEM pistons without machining or do all aftermarket rods require it?

As far as the piston/ring gap/failure argument, I agree there has been no proof of what is causing this and I am leaning toward the possibility that Mazda has likely already addressed wall wetting and subsequent piston failure with the PU piston design. So that particular problem may not be a problem any longer, but only time will tell. I will certainly address heat management with the new motor via fan control and having a working tstat. IMO I fall into the Stage I requirements so no rad needed.

I am just about to mark option 1 off the list. To do that to a brand new LB is...well pointless really and doing all that work would be better suited for a salvage motor. Finding a motor out of a CX7 would be ideal.

Thanks for all the input guys and keep the ideas coming.

Option 2. Don't forget I will have some pu pistons shortly.

I do recommend you wait for @breakfasteatre;'s results when his pu goes under the knife.

32K KMs. COBB Stage 2 OTS map. 20% leakdown in cyl 4.

EDIT. We can take measurements on anything you guys wish to assist in formulating a more concise opinion on these matters. Top ring gap, bottom ring gap, how far down we push the rings into the bore before measuring, condition of pistons, oil stains etc.

what is the ETA of his teardown?

BTW does anybody have information on what rods fit without machining or do all aftermarket rods require machining to fit the OEM pistons?

I know my K1s would require it but seem to remember that Carrillo rods are already tapered on the small end but not sure.

there is also the pin diamater to match up. IIRC OEM is 22.5mm and forged pistons are typically 22.0mm or I have that backwards...lol


@Tomas; cuz you just did this...:)

I believe D Day is scheduled for sometime in April.

I plan to have my swap completed by mid April...we'll see how that turns out lol

Stock wristpin is 22.5mm.

Stock wrist pin is 22.5 mm. Some aftermarket rods and pistons for our car are 22.0 mm.

EDIT: Dustin beat me to it. So much orange in this thread!

i think the eagles rods either fit stock pistons or they have a TON of extra meat on the small end to not worry about shaving them down some.

Remember to check that machining on the cheaper rod alternatives. They may not be in spec.

I would personally just get Carrillos made for the OEM pistons. The proper sizing and machining already done is worth it.

Well they don't give those rods away do they and if they are for the 22.5 does that mean they are tapered for the OEM pistons or is there a special P/N for those?

A-beam 22.5mm = 895
H-beam 22.5mm = 1015

I'm with lex on this. To be the least intrusive on a new motor, just swap rods, use the pu pistons and call it a day. Then sell all your old parts and profit.



Sent from your couch

Honestly, I'd say option 1.

If you have another method of transportation take your time and do it right. The 2nd leaves way too much to chance in the future where you may be stuck again doing what you should have from the beginning.

Cut no corners and take your time.

I only have this car so that is a major limiting factor unfortunately.

Looking into new rod options and machining options for my K1s and will most likely take that approach and add some ring gap to the top ring for insurance.

@Dano; , are you going to be at the epic meat in april?

Get new long block and don't crack it open ..

that option only comes coupled with selling the car :)

seriously...no way I'm going through all that work, again, to put in a completely OEM motor.

god when I look back. Broke my back doing a drop in build only to have one issue after another. Then a month later the clutch goes out so I have to pull the tranny anyway. Now a month further I am planing to pull the front support and both at the same time...lol

I am 95% sure I will be going with Carrillo A or H beam [$120 difference] , OEM pistons, opening up the top ring gap, and letting it bump. Although I would prefer H beams, I bet the Carrillo As are stronger than my current K1 Hs. And the package of A beams and OEM pistons seems like a better fit than overkill H beams and OEM pistons. IDK yet.

With proper heat management I think this setup will support 450WHP all day long and I think i'll only get it up to around 425ish.

Carillo H beams, Dano.

This could be you... except the extra testes are found inside the motor.
http://3.bp.blogspot.com/-l5MS7FBqyl.../trucknuts.jpg

Bro, I'm packing heat!

Nah.. it's not him... there's no dick attached to that balls sack. Or it's a microscopic one.

@Dano;

Somewhere in one of these threads you were talking about doing the fan controller mod for added temp controls. You were having clearance issues for adding the sensor in the upper rad hose.

While perusing the E-Trailer(?) website, I noticed the adjustable thermostat with the
capillary tube sensor. It's like the thermostat in the typical A/C unit, where the little
pecker is just stuck in the evaporator. In this app, it'd be in the radiator, but same
theory. Then you could have an infinitely adjustable control. Just a thought.

Jegs has the same thing: http://www.jegs.com/i/JEGS+Performan...52125/10002/-1

I am looking into a different solution that if it pans out, will be even better.

So its settled.

Carrillo tapered H beams ordered today from Edge

OEM pistons will either be sent out for cryo treatment or the tops ceramic coated, still TBD.

this should make a very nice hybrid forged internals package with minimal invasive action taken on the new block.

Ive heard cryo is a waste of money. I read an article about it, somewhere

yes I am now aware of that and until today had not even considered it...but any new tech is typically considered bunk until it is the shit at some point.

lol