Beware of JE pistons Part #271775

[Spawn_CA18]

subject is changed but ,

same thing happening with Wiseco pistons you know . But they are writing a note to manual that says jets may need modification . but i shaved a little from pistons to make it work . If you miss that point you can deal with lack of jetting and stuff


also i'm using K1 rods since 25.000km with over 300HP. 2-3 times i have faced with fuel cut but it handled nicely. I recommend it .

cheers

[TheMAN]

With the JUN cams (264* 9.3mm ex/int.), the compression stayed the same. With my HKS cams (264* 8.5mm intake and 272 8.5mm exhaust), the compression seem to be dancing around, but for now it appears that the block had some out-of-round cylinders which led to the over-boring of the block. We'll find out soon enough because the HKS camshafts will stay for now and I should be re-installing this engine some time today.

And yes, it has been confirmed that there are two different versions of the modern CA18DET in the fact that one pumps out 150psi per cylinder and the 180psi per cylinder. And I know this because I've touched more than enough standard CA18's coming from Japan to be distributed to would be CA owners. I have no idea what the difference is (HG, Pistons, Head, etc.), but I don't care either; as long as it functions.

I've had a Tomei (270* 8.8mm intake) camshaft snap on me for no reason, so I had regrinds done based off that profile and they had done pretty well. The Tomei broken camshaft and the good Tomei camshaft are hiding in my garage in a box somewhere. I may revisit this profile someday, but I am in no rush. The HKS camshafts have been good to me in the past, but I have had some compression issues with this same motor that I have been using for nearly 11 years. I'll get to the bottom of this today. The JUN units seem to be the drama-free units. I mean, to have a JUN 272* 10.5mm lift camshaft set in an engine running hydraulic lifters and doing it reliably to the tune of 630whp is nothing to sneeze at .

Lastly, each engine uses multi layer head gaskets and are selected accordingly to specs of the block/pistons. ARP head bolts are also incorporated to secure these engine because they do see in excess of 35psi of boost. The 630whp motor uses crower rods, CP 83mm pistons and a heavily machined head (port/polish, clearancing). Hope this answers your curiosities

head gaskets stayed the same throughout the S13 CA18DET production, but according to FAST, the early 88s (from May to September 88) had one type of piston, while the ones built after September 88 had 5 different "grades" of piston... interestingly, "grade 1" is the most expensive out of all pistons... the oversized pistons were obviously service level parts and never changed throughout the production years (they list as from May 88 to January 91)

so I wonder if it's the early ones that are "high compression" or the later ones?

[TheMAN]

subject is changed but ,

same thing happening with Wiseco pistons you know . But they are writing a note to manual that says jets may need modification . but i shaved a little from pistons to make it work . If you miss that point you can deal with lack of jetting and stuff


also i'm using K1 rods since 25.000km with over 300HP. 2-3 times i have faced with fuel cut but it handled nicely. I recommend it .

cheers

what's the point of the stupid note if they're too lazy to make the piston the correct shape after people spending so much money on them? It doesn't look like they even care about the customer or racer but just want to take money instead

they need to get their act together and fix this silliness that gives aftermarket performance parts a bad name..... people at dealerships like to talk trash about hotrod parts because they fit poorly... sadly it's true for many american made aftermarket performance parts I've seen, but the japanese pay attention to the details and try to make it right based on my experience... too bad JDM performance parts are harder to get and expensive

[boost_boy]

CP got them right the first time. Problem with the CPs are that make a loose fitting piston which equates to them being noisy, My Wiseco pistons in my fully built motor not only had to be machined for the reliefs, but I had the valve slots widened an deepened as well.

[tommey]

CP got them right the first time. Problem with the CPs are that make a loose fitting piston which equates to them being noisy, My Wiseco pistons in my fully built motor not only had to be machined for the reliefs, but I had the valve slots widened an deepened as well.

Could you explain what you mean by "loose fitting piston"?.
Are you talking about piston til cylinder clearance?
If so it is the machinist who sets that and CP, JE and Wiseco uses the same material usually.

[themadscientist]

If I recall it had to do with the expansion of the material the pistons were made of. They expanded more than some so cold they rattled in the large bores required to use them.

[tommey]

That's a little odd since they generally use the same alloy and clearances.
Wiseco often have offset wrist pins, that's a way to quiet them down.

[themadscientist]

Dee or Ryan will have to weigh in on that. That's the way I remember it. I never got a chance to hear my Todas run.

[boost_boy]

For some reason or another, the CPs seem to expand a little more than the wiseco units (could be wrong). In 1999, I had one of the first, if not the first set of wiseco pistons custom made here in the U.S. for the CA18 in which they took one of my stock pistons and copied it. That resulted in 4 broken oil squirters (stupid machine shop) and then three of those pistons were killed using a guinnea pig (the first one for them) 1988 nissan pulsar ecu re-mapped by Jim Wolf technology.

So I purchased the CPs in 2003 or 2004 (don't remember), had the cylinders professionally honed, installed them and had done pretty well with them for years to come. But over the years, that engine had been serviced on different occasions (new rings) to include hone after hone after hone, but never appearing to need an over-bore due to the bores being wiell within the manufacturer's specifications. The CP pistons were noisy when cold, but will eventually quiet down somewhat after the engine reached normal operating temperatures. The build before I had the engine bored over was the last straw because the compression was all over the place. So I tested all cylinders cold, hot and also checked it while the pistons were cooling down and the compression numbers were constantly changing which basically showed me how much these pistons expand and shrink in a short amount of time. The wiseco pistons were actually quieter than the CPs, but it could be just wear on the bores

[float_6969]

I only have experience with CP's, so I can only speak of them. I CAN tell you they are VERY noisey when cold. Like I thought I had a bad bearing noisey. It goes away when things warm up. As long as you don't beat on it until the engine heats up, you're fine, but it is a nuisance. This is the primary reason I went with Supertechs this rebuild. They use a higher silicon content aluminum and have a very low rate of thermal expansion. Supposedly they aren't as strong, but Supertech claims they have no evidence of piston failure from the "weaker" aluminum.

[TheMAN]

the alloy compound plays a big role in piston slap/expansion rate... offset wrist pin can help a lot too
streetable hypereutetic forged pistons don't make a lot of noise

[dash]

Too bad nobody would just make a good oe quality cast piston for a reasonable price and quit fkn around
Greed I guess?
536whp cast piston would suit 99.99999% of us fine
Stock toyota gze supercharged pistons survived in 4,5 and 600hp 1.6L
Always silent. Cost $47 each brand new at the toyota dealer

[themadscientist]

Stock pistons with ceramic coated crowns?

[TheMAN]

Too bad nobody would just make a good oe quality cast piston for a reasonable price and quit fkn around
Greed I guess?
536whp cast piston would suit 99.99999% of us fine
Stock toyota gze supercharged pistons survived in 4,5 and 600hp 1.6L
Always silent. Cost $47 each brand new at the toyota dealer

I'm sure mahle makes aftermarket stock replacements and sells them in europe

[dash]

Thats right! .....now that you mention it. Marketing maybe
I followed an austrailian mitsubishi 2.6 sohc build, guy told me he ran exactly that - Mahle cast replacement
T4 @30+ psi punishment.
Even their cam regrinds seem significantly stronger perfomers than what U.S. grinders served our starion community
It appears they definitely got the "good" stuff
Only requires a li'l effort I suppose.... either to cross the pond, or spur u.s sources

[themadscientist]

Mahle makes nice stuff.

[themadscientist]

Mahle makes nice stuff.

http://www.us.mahle.com/MAHLE_North_Ame ... ne-engines

The requirements on pistons for gasoline engines have become ever greater over the past few years. The thermal loads have risen as a result of higher power demands. The stresses at average ignition pressures have increased through knock control, direct fuel injection and turbocharging, while high speed concepts have led to an increase in inertia load. MAHLE has responded to these requirements by utilizing longstanding experience and innovative concepts, which continually adapt the existing product program to the challenges of tomorrow.

The MAHLE program for gasoline engines
The piston program for gasoline engines comprises weight optimized aluminum pistons with diameters from 65 to 110 mm for the highest requirements. The pistons are produced from cast or forged, high-temperature resistant aluminum silicon alloys. These alloys and the refined casting technology from MAHLE enable an ideal combination comprising pistons with low weight and high structural strength to be produced: for example the MAHLE ECOFORM® pistons. Based on the ECOFORM® piston, the next generation of MAHLE lightweight pistons was developed: the EVOTEC® piston. The optimized design enables further weight reduction, while increasing the load-bearing capacity.

New challenges – optimum processes
Modern engines with variable valve train or different direct injection concepts require pistons with a complex geometry. This often leads to a higher piston weight due to involved crown shapes. To achieve as ideal as possible a combination of low weight and high stability despite this, the suitable choice of material is just as crucial as an optimum production process. MAHLE utilizes its longstanding development experience to best effect here, both in forging and casting technology.

Improved coating for less friction
The piston skirt for gasoline engines with cast or steel cylinder surfaces is usually coated with GRAFAL® at MAHLE. GRAFAL® helps to reduce friction and hence increases the scuffing resistance. A further advantage of GRAFAL®-coated pistons: They enable a closer fitting clearance which leads to significantly lower engine noise in conjunction with complex piston forms.

For the application in aluminum cylinder surfaces, MAHLE uses the iron particle reinforced synthetic resin coating FERROPRINT®. MAHLE's new FerroTec® galvanic iron layer is another ongoing development available on the market. The FerroTec® technology coats the entire skirt evenly, resulting in improved running properties. These coatings are necessary to enable the combination of aluminum pistons with pure aluminum engine blocks and hence represent an essential contribution to an overall reduction in engine weight.

[tommey]

Remember that it`s the rings that do the sealing, not the piston itself.
JE,CP and wiseco uses the same material, have you guys never measured your clearances before assembly?
That could clear some of this up i belive.

I understand that you trust the machine shop and maybe dont have the tools to measure.

I have used mainly CP pistons, never had any issues or alot of noise.
Typically i run 0.09mm clearance on an 83.5mm CA pistons, thats microsopicaly more than CP recommends.

[TheMAN]

I can't completely agree... different mix of alloy between the brands plays a big role in the expansion rate... the amount of silicon affects this in pistons
the boring sizes also do play a role in piston slap... it all depends on the machinist and their judgement on bore size... old timers are used to pistons that have high expansion rates and will punch a block bigger than people who are younger or kept updated in engine technology who understand that modern piston designs allow for tighter clearances

oh mahle makes great oil filters too... OEM to BMW and others, including mazda in europe