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Where to get 3.4L Pistons

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vettedog72

Jedi Knight
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I will be ready for pistons for the 3.4L S engine this summer. I want the 9:1 CR and I prefer a cast piston like the originals. I solicit your advice and experiences.
 
I had Ross make the last two sets for the 3.4S engines I built recently. Of course they are forged rather than cast and the piston was much like the 4.2 redesign in that it had a much shorter skirt. If you want them before the end of summer then you need to call them yesterday.
The original manufacturer for the 3.4S 9:1 piston was Brico and I guess they are long gone.

Alan T
 
Another outfit to contact: Wiseco, in Mentor, OH.

They made us up a set of oversize for a Ferrari V-12.
I was impressed with both the product and the service.
 
Thanks to both of you for the information. Both of you have experience with the forged type which are far superior in strength to the cast. I guess I might as well find someone to forge a set for me. I would put the set of cast pistons back in but one pin is missing and they are 8:1 CR.

I do hope there will be a few more comments before my decision is made.
 
Are you looking for oversized pistons, or replacing them due to 1 pin missing? If it is the latter,call this guy. He will have what you need Jack White, Jagnut Jaguar spares, 1 540 743 4037. Leave a message, and he will call back. If you are looking for new, what about the usual Jag parts suppliers, like Terrys Jag, Welsh Enterprises, and the like?
 
The pistons I have appear to be good with little mileage on them, but they are 8:1's. I am looking for a pin so I will give Jack White a call. Many years ago when I was actively putting things together, the advise I got was use 8:1's as every body got way too much detonation/ping with the 9:1's. I want the 9:1's but my practicality may over rule my desires. I will take the pistons down to the machinist and see if they will pass muster and if so, I will pursue the pin from Mr. White. None of the other vendors had cast 9:1 pistons last summer and this summer BPNW says they can order them from the UK for me. Frankly, I have jumped back and forth on the CR to use. If I buy new pistons I will buy 9:1's; if I can use the old ones, they will be 8:1's. All advice is welcomed and thanks for the reference to Mr. White.
 
I stayed with the 8:1 pistons in the 3.4 Mark 1. I figured if I travelled around with it I would not have to worry about what type of fuel was available, as I did not want to back off timing for detonation/pinging if low octane was only thing available. Especially if going to see Targa in Nova Scotia or Pan America in Mexico. Car is going to be used for Rallying and track events.
 
I second LarryK's thought process. We're only gonna see more of the "blended" fuels in the forseeable future. If it were to be a TrailerQueen and you carried your own fuel along it may not be as big an issue, tho.

We don't have the "blends" here in Florida *yet* but it appears we may soon have ethanol to contend with. We're in the "flatlands" so 9-ish may not be as big a pinking issue, but if you start puttin' yer boot in it with a steady diet of "lighter" fuel it could become problematic.
 
I know a few decades or so ago, no body wanted to run the 9:1's because of pinging. The confusing part of this is the American mussel cars were and still are 10.75 and even higher running on pump gas and making high HP. One of the significant requirements to run the high compression was an aluminum head vs. cast iron. So, it left questions in my mind about the Jag ping problem. Now comes a "new" piston design, at least to my attention, that eliminates the symmetrical dome. It is replaced with a non-symmetrical shaped dome. Some how this is suppose to cause better fuel burning and less likelihood of pre ignition or detonation.

I am at a close for a while with my Jag restoration as my mechanic (son) is enroot to LSU for the fall semester (and so is my money). We are getting very close to needing the engine rebuilt and when I do, I am going for the 9:1's with the new dome design.
 
A friend of mine and I were just talking about this last night. He's shooting for 11:1 compression when he rebuilds his MGB (assuming he gets an aluminum cross-flow head). Interestingly the new (circa 2003ish) Chevy Trailblazer 4.2 I6 was 12.5:1 and ran on regular. It had all kinds of fun trickery like variable valve timing though. I've always wondered though why with Jag's 9:1 is "high" where with american cars that's low... 5.0 Mustang was something like 10:1 stock and ran on regular...
 
With electronic fuel management and knock sensors... /bcforum/images/%%GRAEMLIN_URL%%/wink.gif
 
wonder how they run now with what passes for gasoline. The now 93 octane is pro'lly close to 100 in the old rating system used back in '66, so mebbe it's a moot point. <shrug>
 
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