pistons
 

I have a motor that should be a 454mag.
I know is was redone and it does have dipple rods. My concern are the pistons. All the forged pistons I have had where JE and these pistons look just like my stock 7.4 pistons. How do you tell if they are caste(sp) or forged?

Cast pistons will have a 'parting' line on the inside were the 2 halves of the mold come together. May also have steel plates that are visible on the inside next to the piston pin holes.

Forged will have neither of the above. Also usually a smoother inside surface. Not a sandy texture that is common with cast parts..

These pistons that should have been forged have a sandy look to them which made me wonder about them. Also when I compared them to the 7.4 pistons all the places number where the ones I have where ground down. Guess I will be buying pistons now. Thanks for your input.

It's possible the original forged pistons were replaced with hypereutectic pistons, which have a much greater strength than cast pistons but are considerably less expensive than forged pistons. I've used the hypereutectic pistons in hi-performance applications without any problems. If you're going to be doing mostly full-throttle running the JE or SpeedPro forged pistons would be my choices. I prefer SpeedPro because they tend to be a little lower in price than JE but both are excellent pistons. What compression ratio were you thinking of running?

I got this motor in on a trade. The number one piston is odd since all but it have valve reliefs but it. The cam I am running is larger than the cam I took out. Money is a issue on this motor at this time. I am thinking about running as high of compression as I can to run on 93 gas.

Dyno and SuperV are running about 9.6:1 compression on pump gas, Dyno has hypereutectic pistons while SuperV has forged. otherwise the engines are identical. I can put together a parts list for you if you'd like. Then you can check prices locally as everything is supplied by Federal Mogul.

I have about 230 hours on the hyperutectics right now no problems run them on pump gas to 5100 rpm...

Maybe next summer you'll actually move the throttles to the wide-open position,,,,,

I would be interested in the list. They are hypereutectic pistons but one does not match the rest.

Let me know what heads (like stock rectangular-port, Merlin-oval,,,) you plan on using so that I can give you a good piston recommendation.

The heads are stock square port which I am planning on getting ported and polished. I found someone in the are that has a flow bench. The cam is a roller which I had in my 540 I still need to find the spec sheets on it.

Dyno, do you have to use 92 octane all of the time with that 9.6 to 1? I forgot, are you using aluminum heads? Just curious. It's hard to get good premium on the water sometimes.

No, he can run 89 octane without changing timing, which is set at 32.