[whales]

What rpm do cast pistons decide that enough is enough. I'm rebuilding my 351C (advised by members of vmf) and have to decide on forged or cast pistons. I have never revved a ford motor past 5500 rpms and don't plan on being to hard on this motor. The engine builder I'm dealing with said cast pistons are fine for 5500 and below? Is he right

 

[70coralmach]

I would agree with your engine builder as far as cast being ok for your application. There is one other thing to be aware of, forged pistons resist detonation better than cast. Your engine has 11:1 compression and pump gas isn't what it used to be, probably would have to go a little easier on the mach if using cast , or maybe a hotter ignition(hidden of course) may help. Just my .02, hope this helps.

 

[Hottarod]

If I'm having to buy new pistons I won't buy cast ones but then Im drag racing. I wouldn't run 11:1 compression with cast pistons either. Also(just as a side note), I tend to over build my stuff, LOL.



You can see my 65 fastback at: http://hottarod.stangnet.com/
http://members.aol.com/macstang/Gifs/macstang3.jpg

 

[mrgem]

Hypereutectic (sp?) cast pistons are fine for a street motor- even one that gets exercised regularly. Eleven-to-one compression is pushing the limits, though. If you are determined to use 11:1 compression pistions, you might want to consider thicker head gaskets to lower it to around 10:1.

Glenn Morgan 66 GT Fastback 351w+toploader

 

[camachinist]

Hi Bob,
Cast pistons are fine for most non-racing applications...remember, quality counts..

As noted before, they are less resistant to detonation and pre-ignition than hypereutectic cast and forged pistons so make sure your ducks are in the right row to manage that aspect of engine operation.

Since you're in the middle of an engine project, you might consider putting some info about it in your sig line or bio area so we can review what you've decided on as you go along...or maybe do a web page on your project...

Sounds like you have a reasonable engine builder....

Pat
http://albums.photopoint.com/j/View?u=1570936&a=11937754&p=42910787.jpg