Build Thread Want To Blow 5 Years And $50k On A Foxbody? Step By Step Instructions Inside!

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Haha. True story Colin. If it's anything like my painter, I won't see that engine until the summer!

Hopefully it's only a little bit late as a worse case scenario. It's weird how excited we get when YOUR build goes well and how disappointed we all get when things go bad and it's not even our car, time nor money invested. We're simply followers. Even though I have my own build that consumes my time I still enjoy following yours and as excited as I am to soon be turning that ignition over for my own car I eagerly anticipate a successful start up, test and tune of the beautiful machine you've crafted. :cheers:
 
Hopefully it's only a little bit late as a worse case scenario. It's weird how excited we get when YOUR build goes well and how disappointed we all get when things go bad and it's not even our car, time nor money invested. We're simply followers. Even though I have my own build that consumes my time I still enjoy following yours and as excited as I am to soon be turning that ignition over for my own car I eagerly anticipate a successful start up, test and tune of the beautiful machine you've crafted. :cheers:

I'm glad that my thread inspires people as much as other's have inspired me. I know how exciting it is to see other builds evolve and come together. That's why I did this thread. I appreciate it man.
 
I'm glad that my thread inspires people as much as other's have inspired me. I know how exciting it is to see other builds evolve and come together. That's why I did this thread. I appreciate it man.


Whoa. I thought you did this thread as a preview for the work you'll be doing on mine.

Fortunately, my motor is done already. :D

Let's stick with the plan and not forget why we're all here. OK? :nice:
 
Well, when it rains, it really does pour. I received an e-mail from my builder that the new pistons are 18 grams LIGHTER than the old ones. I called up Probe and they said that the specs on their site are "just a guide", and piston weights can vary up to 30 grams between batches. All the pistons are within 1 gram of each other, but the 18 gram weight difference is a problem. The tech from Probe said to install them and everything will be fine. Up to 20 grams lighter is not a problem, according to him. I'm not sure if I trust that advice. I know up to a 2% overbalance is typically done, but my problem is I do not know if the rotating assembly was previously setup for an overbalance. I don't have the bobweight information. My builder said he isn't comfortable with anything more than a 3 gram difference in weight per piston.

My problem is that Probe has these on backorder for another 4-6 weeks, so trying to find a set of heavier pistons is not really an option unless I can find a vendor that has them sitting on the shelf. The only other option is dropping another couple hundred on getting the entire rotating assembly rebalanced. It's money that I really do not want to spend. FML
 
Yea, that's actually a third option I was considering. Returning the Probes and getting a comparable set from another company. I won't be buying anything from Probe in the future after them basically telling me to pound sand.
 
I had the same issue with JE, they couldnt give me a straight answer on a pretty simple piston question, about their piston. The guy was a total ******* and even went as far as giving me a false name. I asked around to see if there was anyone specific i should call and a week later i finally got an answer, but needless to say they lost any future business from me.
 
The fish idea was scrapped years ago, unfortunately. The feeding system proved to be too complicated.

The crankshaft is getting rebalanced for $150. Cheap peace of mind, in my opinion. Should have everything back in 2 weeks or so.
 
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I don't see what the problem would be with putting pistons in that weigh 18 grams less, as long as they ALL weigh 18 grams less. A piston is reciprocating weight, not rotating weight. As such it should have no impact on the rotating balance, as they only go up and down, not round and round. This is why the big end of the rod is weighed and balanced separate from the small end of the rod. The big end goes round and round, while the small end only goes up and down. Some one please explain why if this line of thought is wrong.
 
You're right, and my engine builder and I had the same discussion. Piston weight does affect rotating balance, just not to a great extent. That's why probe told me to just run the new pistons. The issue for me is that I don't have the bob weight information from when the assembly was originally balanced. I don't know how much of an overbalance was already spec'd out. The lighter pistons will cause even more overbalance, so I'll just sleep better knowing that the balance is within the tolerances it should be.
 
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