Stock piston specifications

I spent today at the section of the SEMA show where performance engine product companies are located. Spoke with pretty much every piston manufacturer that exists about Fiat SOHC options. As I predicted in my earlier post, no one even knew what these engines are and only one or two guys had ever heard of the X1/9. You have to remember that we are a very small crowd. So it was like I thought, you need to go prepared with the exact specifications for them to be able to look it up in the database (which I did). And even then they could not say what might be possible - other than the standard "custom made from scratch" reply. So my original intent of finding a existing option does not look promising.
 
Dr.Jeff said:
I spent today at the section of the SEMA show where performance engine product companies are located. Spoke with pretty much every piston manufacturer that exists about Fiat SOHC options. As I predicted in my earlier post, no one even knew what these engines are and only one or two guys had ever heard of the X1/9. You have to remember that we are a very small crowd. So it was like I thought, you need to go prepared with the exact specifications for them to be able to look it up in the database (which I did). And even then they could not say what might be possible - other than the standard "custom made from scratch" reply. So my original intent of finding a existing option does not look promising.
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Wow that is really odd. At least someone at JE should have know the Fiat products, they make oodles of pistons for them for many engines old and new.
https://www.ebay.com/itm/JE-86-4mm-...122786&hash=item1cb2f8048d:g:e3IAAOSwzbdbTl5L

https://www.ebay.com/itm/312400-JE-...170510&hash=item2f29a04035:g:jDkAAOSwlThcNmbt


I talked to a guy from Wiseco a few months back at a local Time Attack event and he had knowledge of the Fiat engines and we discussed the differences between the Wiseco and JE pistons. Maybe I was lucky enough to just find the one guy.

Did you talk to any of the LCC guys our of Asia?
 
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I don't know why you had the experience you had. But sometimes you can get someone who has less than complete knowledge. For instance I called Cometic about making me a custom gasket. (I was looking for a very thin head gasket.) The guy I got on the phone insisted that Cometic knew nothing about the Fiat SOHC engine. I was very surprised as I was holding a Cometic head gasket for the Fiat SOHC engine in my hands while we talked. Perhaps it was just a case of miscommunication? Maybe I got the new guy? Maybe the janitor picked up the phone while the engineer was out on a smoke break? Who knows?
20191106_105313.jpg 20191106_105323.jpg

Wisco lists Fiat pistons on page 65 of their catalog.
Wossner also has Fiat pistons in their catalog: https://wossnerpistons.com/collections/fiat

I suppose that some piston manufactures will not allow someone to "copy" a piston design from another customer, so when you ask if they "know" about Fiat pistons they may not be allowed to admit that they had manufactured them before. Maybe? Maybe they lost the file (assuming they keep files)?
But I don't believe that most of the major piston manufactures have never manufactured Fiat SOHC pistons. I know they have because I have some of the pistons that they manufactured.

I can relate to your situation though. I'm in the process of getting some custom pistons made right now too. I'm no expert so I have enlisted the help of a semi local professional engine builder to help. I've asked him for his recommendations and given him all of the parts he needs to measure to order the right custom pistons. He buys lots of custom pistons (and other stuff) and knows all of the right folks to talk to. He talks to them everyday. I trust him and will allow him to choose the manufacturer (a lot of change in the industry right now - consolidation). I don't expect the pistons to be cheap, or to arrive at my door tomorrow, but I'm confident that they will be right.

Good luck with your quest.
 
You can order high compression pistons from Ross thru Allison Auto, so they should have the basic design specs to modify from.
 
It is true that there will be a huge difference in the info you get depending upon which specific person you happen to be talking to at any given point in time. I've found this to be pretty much universally true for many decades throughout the automotive industry. Seems there is a tendency for them to not admit they don't know something, so they make up crap instead. But at the show I was able to talk with several of the guys at the same time (from any one company). The show is so big that most companies send everyone to help man the booths (which can be large and busy). So when you approach them to ask a specific question, everyone tends to gather around hoping to be the one with more knowledge. That usually results in the guy that actually knows about your question speaking up, at which point you focus your attention on him. However it may have been possible the one guy that did know was in the restroom when I was at each booth, who knows. Normally I have much better results when I bring questions like this to SEMA. It is a unique opportunity to have direct access to the whole crew at once and be able to exchange a face to face real time dialogue with them...including the engineers, sells crew, product developers, service techs, etc. Guess this wasn't one of those times.

Perhaps one big difference between the experiences of others - regarding Fiat SOHC pistons from these companies - is they have been about high compression normally aspirated applications, while I was asking about a turbo application for that engine. That may have thrown them off because turbo applications have specific requirements.

The links offered in the recent replies are for the later Fiat engines. Although the bore diameter is the same for one of those links, I'm not sure if the other criteria will apply. For example in this link they are stated as 9.2:1 compression with a stock head, but those heads are different than the US spec X1/9:
https://www.ebay.com/itm/JE-86-4mm-...122786&hash=item1cb2f8048d:g:e3IAAOSwzbdbTl5L
Anyone have additional info about this?
 
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I am not the Fiat Engine cross reference wizard but aren't the 159A and 176A SOHC?
https://en.wikipedia.org/wiki/Fiat_128_SOHC_engine

All these guys have knowledge of pistons they should have been able to talk it up with you, not sure why the didn't offer more info. Maybe if you were talking about a Hellcat or Coyote they would have been all over you. I will have to check but I believe these "9.2" pistons are the high performance version what I am running today. The difference is the wrist pin location, all else essentially being the same. In application I think these end up being a little lower compression than OE when used in the 1500. I will take a look.
 
I remembered this post from some time back which has a reference to my current set of pistons in it. For a stock engine install if the valve pockets are opened up and made them equal (original pistons vs these guys ) there would be less compression than stock (8.7 CR before opening up the valve pockets). More info to ponder. I don't know if the JE pistons linked in the previous post are their version of what I have but is looks to be possible. The link was really to illustrate JE knows Fiat pistons whether they want to talk about them or not.

https://xwebforums.com/forum/index....erified-your-9-2-1-pistons.23685/#post-195154
 
I've bought 2 sets of pistons from Vick that came in Persan boxes; their website has lots of info, here is the Fiat file. for example, their model 262 is also 124 fitment with 8mm dome.
 

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Dallarax19 said:
Maybe if you were talking about a Hellcat or Coyote they would have been all over you.
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Absolutely. And frankly the SEMA show is mostly about American muscle car/hot rod stuff, and of course trucks (lots of trucks). However that's not to say there aren't a lot of import specialist companies - there certainly are, but mainly for Asian vehicles. So the show reflects the market here in the US, and it is obvious when you look around. For example many of the companies include some sort of a show car as part of their display, and I'd venture a guess over 95% of those cars are American with the remainder being Asian - and a lot of trucks. But usually when discussing European import needs I have better luck than I did with this.
I should mention that a couple of the piston companies I talked to suggested I call to confirm things. Although when I asked who I should speak to, they said themself. So I would not anticipate getting any more help over the phone than I did in person.

This experience was very similar to the one I had with Cometic gaskets (and a couple others). I think it really comes down to what DallaraX19 said; these companies have become very successful catering to the US domestic vehicle market and really aren't very interested in spending time on other stuff. By comparison, if you approach one of the turbocharger manufacturers (as well as many other product companies that tend to have a large presence in the import scene) with questions, you will get lots of really great help.
 
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maybe ask them about "historic" pistons .......(lolz)

all of the big piston manufactures have made slugs for the SOHC engine.

you need to be able to tell them:

intended use
fuel type
rpm range
boost levels
valve sizes
valve lift @ tdc
comp height
bore size

they will then be able to suggest:

ring pack placement
crown thickness
pin thickness / finish
cut-out depths
"droop" type to assist with noise
material selection

its up to the engine builder to calculate / determine
squish
comp ratio
piston to valve clearances

lots of pretty pic's

https://www.facebook.com/IasaForgedPistons/

its not rocket science !
 
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