I plain on rebuilding my bottom end over the winter to handle more boost. I plain on runnig manley rods, but waswondering if t would be safe to run the stock pistions. New ones are about $700. I dont want to sound cheap but can the stock ones handle the additional boost? I only wanna do this once so any advice will help

 

When most people rebuild their motor, they figure they might as well change out the pistons while they already have the motor apart. But, really the weakest part in the L motors is the rods and not the pistons so you should be fine with the stockers.

don't quote me on this

 

once you change the rods, the pistons then become the waek point. your prob better off getting new pistons. JMO

 

While it is apart, spend the money and replace the pistons, or spend the money and the time later rebuilding it again with new pistons.

 

The weakest links are the rods. I believe our stock pistons are hypereutetics, which are much weaker than cast or forged pistons. Ive never heard of anyone melting a whole in a stock piston though.. I went with the CP pistons, noisy but effective...

 

That brings up a good question…

I hear “this” piston is noisy verses “that” piston and it always seems contradictory. I wonder if it is not the piston so much as the machine shop doing the work. What exactly would make one piston noisier than the next?

 

You are right, it has lots to do with how much clearance the machine shop puts in the bore. The CP pistons are very strong and have a lower silicone content than say....the Probe pistons. The probe pistons can be ran with less piston to wall clearence but are not as strong.

We will have some great engine combos shortly!!!!!

Hope this helps.

 

i actually heard that our stock pistons are forged, i could be wrong though. hyperruetetics are cheap and good as long as there is no detonation

 

yes, I believe our pistons are forged...interesting that the vendors didnt step in and correct anybody there.....

 

I remember reading where lightning boy had problems with the stock pistons where the wrist pin is held. The aftermarket pistons have a much bigger area there. The only reason I would go with the stock pistons is if you just are looking for the cheapest way to build the engine. Take the stock rods out and put the new ones in.

BTW, I have the manley pistons in my engine and haven't had any problems out of them. I have run up to a 150 shot of nitrous with 21 psi boost and 26 psi boost by itself and haven't broke anything for around 20K miles...

 

Yes, I belive that our pistons are forged.....The hyper"pathetics" would prolly melt or have holes burned in them at anything over 10lbs of boost....

 

Do yourself a favor and replace the pistons. It's cheaper now than later.

 

What are the “recommended” piston clearances for the different pistons (CP, Probe, JE, etc) and what are Ford stock recommendations?

 

CP .0035
Probe .0020

 

The stock forged pistons are good pieces, allot of people will recomend that you replace them but I know if anyone is realy is sure of what their limit is.

1 report of a pin knock is not much info. I think it would be safe to say that if you plan on keeping HP below 500 to 550 you would be fine. I plan to use stock pistons and over time I hope to see how much thay can take.