Je pistons

[Nero]

Does anyone know of UK supplier of JE pistons andTotalSeal rings for 2jz?thanks

[alex h]

Leon buys them in - but I doubt if he stocks any. Infact finding any Supra oversized pistons off the shelf in the UK would be hard work. Sorry to be so negative. I would check with JE themselves as to their lead time to get them to you in the UK...then ring round places like Envy, JPS Motorsport, TDI, Whifbitz....etc etc, then compare the lead times.

[Nathan]

I have HKS pistons on the shelf which I can rob from a waiting job if you get stuck, and are by far the best option for the 2JZ in my opinion. We have used JE many times before but they do tend to be heavy, require bigger bore clearances and don't come with any anti-det coating on the crown or anti-scuff on the skirt. The car in my sig was fitted with JE's (by the customer) and suffice to say it did rattle a fair bit. It was also fitted with Total Seal rings. Of course, the one main benefit with JE's is that they are cheaper...

Edited to add that the HKS ones are 87mm, 1mm bigger than stock.

[Nero]

Thanks Nathan.....but unfortunately way out of my budget...I only need 2..and good s/h if poss
cheers

[Syed Shah]

Nathan,

Do you have the weight of stock pistons v JE v HKS? Would be interesting since CW regards stock pistons as 'boat like'.

I thought JE pistons were supposed to be very good, or is this only the case with the PHR special JEs?

Thanks

[Martin F]

Quote[/b] (Syed Shah @ Jan. 13 2004,19:11)]Do you have the weight of stock pistons v JE v HKS?
Also vs. JUN

http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/biggrin.gif

[Syed Shah]

While were at it, I think there is some rod info on SF.

I'll track it down and post it up. It is nice to have it to refer to.

[Martin F]

Yeah can be added to the slowly evolving technical pages i'm writing.

LOL

[Syed Shah]

Found it! http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/biggrin.gif

Here we go:

Bolt size/weight/rod tensile strength/bolt tensile strength

Crower...3/8"/615 grams/150k psi/220k psi

Carillo H-beam...3/8"/600 grams/ not available/ 285k psi

Pauter...3/8"/640 grams/220k psi/220k psi

Eagle...5/16"/525 grams/not available/225k psi

If any has the missing info, or specs of other rods, post it up please http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/smile.gif

[Nathan]

Quote[/b] (Syed Shah @ Jan. 13 2004,19:11)]Nathan,

Do you have the weight of stock pistons v JE v HKS? Would be interesting since CW regards stock pistons as 'boat like'.

I thought JE pistons were supposed to be very good, or is this only the case with the PHR special JEs?

Thanks
lol, I have some good data here but I don't have JE's in stock at the moment....can anyone tell me how much a Mk4 one weighs, minus pin and rings?

You would be surprised how light the stock pistons are (or how heavy the pukka HKS ones are, depending on your opinion).

I personally think the stock pistons do a bloody good job of handling twice the power they were designed for, and for many years as well. Can't think of many engines that can do that.

JE pistons ARE good, as I said, but there are better. I have a problem with rattly engines. JE's do that. Some couldn't give a stuff. HKS pistons run on stock clearances (about 1.5 thou I think). JE's normally run at least twice that IIRC.

[Syed Shah]

I see. I always thought stock were good, but since I only know what sort of power/abuse they can take, that is all I can comment on. Any info on this Chris?

I'll try and find the weight of stock pistons, will allow us to compare with HKS etc.

Have you ever dealt with JUN/Cosworth stuff? Everyone claims they are brilliant, but nobody is using them due to cost. Venom in the US used them, and then switched to Arias IIRC.

[Nathan]

I know the weight of the stock pistons. I know the weight of the HKS pistons. I also know the weight of TODA pistons, the HKS 'H' section rods and the stock rods. All I want to do is find out the weight of the JE pistons.....:)

Never dealt with Jun. Had LOTS of dealings with Cosworth/Arrow/Farndon in my Burton days. Very good. On par with HKS and (I presume) Jun.

[Martin F]

Good info guys.

Will try to knock up a table over the next couple of days with all this info in.

[Syed Shah]

Ok, the JE pistons (non-PHR spec) weigh in at 338 grams. http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/smile.gif

Is that more or less than stock?

[Nathan]

lol, OK. So, the JE pistons are lighter than everything except the TODA ones.....glad I said that JE 'tend' to be heavy....obviously on the Mk4 they are relatively 'light'..:D

HKS piston: 362g
TODA piston: 318g
Standard piston: 376g
Standard rod: 771g
HKS 'H' section rod: 594g

Rods are weighed with bolts and small-end bushes fitted. Pistons are weighed without rings or pins. It's also important to note that the TODA pistons aren't really viable for most Mk4's as the compression with them would be around 7:1. Would love to build a mad 2.5 bar monster with them though. I live in hope.

[Chris Wilson]

Been off the board for a while. back now! JUN pistons are made by Cosworth, here in the UK, but they will not, at all, never, ever sell direct. We buy a lot of stuff from Cosworth, they wouldn't entertain it, I know people who spend hundreds of thousands with them, they too couldn't get them direct. Honourrable comapny! PITA http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/biggrin.gif

My limited experience of HKS ones is they work OK, but are very heavy. Skyline 2.6 GTR ones a considerably heavier than stock Nissan ones, and i have never had a definitive answer from HKS as to whether they are forged or cast. they look cast to me... The Skyline ones didn't have the stock oil cooled head galleries either, which added weight, MAYBE added strength, but seriously reduced ring land and piston crown heat transference.

If I end up doing this 1JZ-GTE engine it will have Cossie pistons. Full stop. They are the best, and worth the price hike via JUN, IMO.

[Nathan]

Quote[/b] (Chris Wilson @ Jan. 14 2004,13:19)]i have never had a definitive answer from HKS as to whether they are forged or cast. they look cast to me...
I am very surprised to hear that Chris. I would lay money down that they were, as are the TODA's. In fact, they look like every other forged piston I have seen, including Cosworth and Accralite. TODA and HKS shown...
http://www.tdi-plc.com/pistonpic.jpg


As for Cosworth being honourable, yes, they are. Very. Shame more companies don't take the same trading policies http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/sad.gif

[Nathan]

And no guesses to see where the TODA one gets it's light weight from!

[Martin F]

Interesting pics.

Is that more rings (seats) on the Toda one than the HKS or just the way it appears in the pic ?

[Nathan]

No, they are just extra ridges machined into the piston. Theres a reason for it (supposedly better than not having them) but I can't remember what it is.

[Syed Shah]

Chris,

Have you got any specs on the Cosworth/JUN pistons? How about their rods etc

Thanks

[Nathan]

Most of the H section rods I have seen have been VERY similar. HKS/Cosworth/Farndon/Arrow/Carillo etc. all look like they have come from the same parents. I think all the bolts are the same spec too- 12.9 multi-heads like ARP. I know that Burton used to buy Arrows and market them under their own name, and I know that HKS used to use Farndon although I think they do actually do their own now because they got a BIG kicking on price. Seems like theres a lot of inter-mixing with things like steel rods and cranks. Probably because setting up the manufacturing for them is massively expensive.

[Martin F]

Errrr JUN pistons are 462g according to their website. Didn't expect them to be 100g more than HKS.

http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/rock.gif

[Chris Wilson]

Quote[/b] (Martin F @ Jan. 14 2004,23:22)]Errrr JUN pistons are 462g according to their website. Didn't expect them to be 100g more than HKS.

http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/rock.gif
We may be comparing apples with oranges, some (naughty) piston makers give the "piston weight" as just that, the piston alone, whreas the standard accepted method is WITh the pin and rings it runs. Not saaying this is the case here, but if a Cosworth piston isn't a LOT lighter than the HKS ones I'd be truly amazed. Also check like for like on bore size and compression height.

Those TODA pistons in the photos look nice, who makes them?

[Nathan]

Good point....don't forget that my weights were without pins or rings, which as Crhis says is not the standard method. I just couldn't be a?$ed opening up the relevant packets but if theres enough interest I might do just that to clear it up. It's a very viable point as pin weight can be dramatically different.

Not sure who makes the TODA pistons Chris, but knowing TODA it wouldn't surprise me if they had their own manufacturing. Remember that all they do is engine parts rather than the jack-of-all-trades HKS. I would have thought it would financially viable for TODA to have their own plant. They could be made be someone else though.....

....hold on, it's just been answered here, unless they are lying...

http://www.todaracing.com/about/technology.html

[Syed Shah]

Nathan, could you get the weight with rings etc fitted, so we have comparable data?

Alternatively, I don't suppose JUN has the weight of just the piston on their site, Martin?

TIA http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/smile.gif

[Martin F]

Quote[/b] (Syed Shah @ Jan. 15 2004,18:42)]Alternatively, I don't suppose JUN has the weight of just the piston on their site, Martin?
Only had the one weight i'm afraid.

Comparison table is in progress.

[Syed Shah]

Brilliant. It would be nice to add as much technical resource information to this site as possible. http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/buttrock.gif

[alex h]

Quote[/b] (Nathan @ Jan. 15 2004,09:13)]....hold on, it's just been answered here, unless they are lying...

http://www.todaracing.com/about/technology.html
LOL... "IBM CATIA (CAD/CAM/CAE) which is the same system used by Honda, Boeing, Ferrari, and" LOTUS http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/smile.gif

[Martin F]

Quote[/b] (Nathan @ Jan. 14 2004,12:26)]TODA piston: 318g
Nathan, is this for the 86mm or 87mm pistons ?

[Nathan]

87mm.

[Martin F]

This table is still a bit rough and empty, but thought i'd post up for more input.

Piston & Conrod Specs (http://www.mkivsupra.co.uk/Technical/Piston%20&%20Conrod%20Specs.htm)

If any of you have more info to fill in the gaps could you send it over or add to thread.

[Chris Wilson]

What's the "Volume" column supposed to ndicate Martin?

[Martin F]

Total engine capacity. Some of these seem to change from the stock 2997cc, i guess due to piston diameter (cylinder overbore) and crown shape.

[Nathan]

The TODA piston isn't actually for the JZA, it's for the SW20, which is why it has a very low compression in the JZA- summat like 7:1. I only posted the info because they COULD be used, but they will never give you 8.5:1. TODA do not make a specific JZA piston AFAIK.

....bollox......scrap all that. My measurements were based on using the stroker crank (90mm) so the TODA MR2 pistons hanging off stock internals will be even lower compression....a 5.5:1 2JZ engine anyone? 4 bar boost...?

[Martin F]

Hmmmmm info came from here

http://www.todaracing.com/products/toyota/piston_kit.html

Apart from the weight which you provided. Are you saying that it wasn't the 2JZ piston ?

[Nathan]

Nuts. You're right. The thing that has thrown all this out is that we have been trying to find a decent piston that gives the compression we want on a stroked crank. the weight I gave you WAS from an MR2 piston yes (from TODA's 2.2 MR2 kit). In the end we have gone for an HKS piston with a shortened rod and 2mm gasket. I honestly didn't know that TODA made 2JZ pistons- in the past we have only ever used HKS ones if building on stock dimensions. The good thing is that the HKS pistons with a 2mm gasket will give 8:1 CR. Just about the right drop for a nice amount of boost without going silly. TODA list theirs as 8.6:1 like you say but we don't know with what gasket do we?

Sorry for the conf http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/sad.gif

[Martin F]

Quote[/b] (Nathan @ Jan. 21 2004,13:04)]TODA list theirs as 8.6:1 like you say but we don't know with what gasket do we?
Where the supplier has quoted a compression ratio, i've assumed this is with a stock gasket. Do you reckon thats a bit sweeping ?

[Nathan]

Hmm....dunno.... Most people would use a thincker gasket anyway so it would be nice to know what the TODAs would give with a 2mm gasket. I'm not sure what the stock thickness is..I've got one here somewhere I think....

[Syed Shah]

1.6mm IIRC. http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/smile.gif

[Chris Wilson]

Just 2 quick thoughts. 5/16 rod bolts are inadequate for a long stroke engine, so those rods with the thin bolts should be avoided. 3/8 minimum!

Running a thick gasket to change compression is bad news, you lose the ultra important squish band. The piston bowl is where compression ratio changs should occur, or in the head chamber volume. With decent rods you should be able to run a good piston protruding into the gasket itself. Squish makes vast difference to det avoidance on biggish bore cylinders.

[Klaus]

Quote[/b] (Nathan @ Jan. 14 2004,14:09)]Quote[/b] (Chris Wilson @ Jan. 14 2004,13:19)]i have never had a definitive answer from HKS as to whether they are forged or cast. they look cast to me...
I am very surprised to hear that Chris. I would lay money down that they were, as are the TODA's. In fact, they look like every other forged piston I have seen, including Cosworth and Accralite. TODA and HKS shown...
http://www.tdi-plc.com/pistonpic.jpg


As for Cosworth being honourable, yes, they are. Very. Shame more companies don't take the same trading policies ?http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/sad.gif
Hi Natan
What is the part# of the HKS piston shown ?
It does NOT seem to be the 2103-RT028 - or ?
The 2103-RT028 has a flat top vs the one shown having a "bed shape like" top !
To my knowledge only the pistons for the new 3,4L Stroker Kit has theese kind of pistons (Piston p#: 21003-AT001)
Thanks, Klaus

[Nathan]

I have cleared this up with Klaus via phone- Martin- the HKS pistons above are from their 2.2 kit for the SW20 so scrap that data as well. This whole stroker thing we are working on has thrown all the data out that I posted. Sorry chaps.

Chris; thanks for your concerns on the bolts. As for the gasket, I agree, losing squish is NOT the best option but at only 0.4mm over standard it's a decision we took and we're sure will be the right one considering the options. If you are concerned about squish maybe you had better inform everyone who is using HKS pistons on the stock stroke 2JZ. They have a flat top and run down the bore with no bowl whatsoever...

Mind you HKS are also the ones running 5/16 rod bolts aren't they....? Maybe they need some direction on their piston and rod design...

[Martin F]

Just come across some pics of the HKS 3.4L stroker kit.

HKS 3.4L Stroker (http://www.supraforums.com/forum/showthread.php?threadid=182124)

Wonder how long till we see one of these in the UK

[Martin F]

Thread back from the dead.

I've noticed that Crower are starting to supply Titanium rods for the 2JZ (INFO) (http://www.horsepowerfreaks.com/ShowProductsMain.asp?ShowSubcatPage=1&ModelCd=SUP4&SubCategoryCd=RODS).
Obviously this will have a profound affect to the rotational mass but would there be any down side to using these rods ? (apart from the light wallet of course http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/biglaugh.gif )

[Martin F]

So nobody has an opinion on Titanium rods ?

[wez]

Quote[/b] (Martin F @ Aug. 29 2004,22:37)]Thread back from the dead.

I've noticed that Crower are starting to supply Titanium rods for the 2JZ (INFO) (http://www.horsepowerfreaks.com/ShowProductsMain.asp?ShowSubcatPage=1&ModelCd=SUP4&SubCategoryCd=RODS).
Obviously this will have a profound affect to the rotational mass but would there be any down side to using these rods ? (apart from the light wallet of course http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/biglaugh.gif )
They sound pretty good http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/cool.gif

[Syed Shah]

That Fabio bloke is using them for his ultra-HP 2JZ app, so they must be good. Just over half the weight of stockers. Wonder how they will hold up with so much power though? http://www.mkivsupra.co.uk/iB_html/non-cgi/emoticons/rock.gif

[Nathan]

Sounds good to me- the NSX had titanium rods as OE so there doesn't seem to be a long-term reliability issue with the material either.

Edit: I might add that the NSX engine wasn't exactly pushing the boundaries of power output though...

[Chris Wilson]

Quote[/b] (Martin F @ Sep. 01 2004,12:06)]So nobody has an opinion on Titanium rods ?
Total overkill on a long stroke, slow revving road car engine. NSX used them to seem trick, IMO, but it does turn a fair amount of revs. Really high revving race engine stuff, much better things to spend money on. F3 engines sometimes run tit rods, and they are very long stroke, but it's so competive with different makes of engine within a couple of BHP of one another that savings in roational inertia become one of the few ways of trying to eek out an advantage. But we are talking 40K engines here.