If you have no plans for Nitrous or boost, what advantages does a forged piston really get you? I know there stronger etc.
But you have to run them a little looser, and with that you will probably use more oil, even with good rings etc.
Just a thought, as it costs more, and if you aren't turning High rpms etc, with Nos or boost, facotry type psitons, for example, should suffice.

 

True.
Forged pistons are only loose until they reach operating temp. They swell to fit the bore. Cast swell less. That is why they are fit tighter.

 

True. But I am looking at if your are doing a heads cam type car is it really necessary to due forged for a solid street car?

 

Because of budget, I have run cast pistons in everything I have built (for myself)with no issues. If they don't go lean, or have severe cylinder pressures, they are fine.

 

I wonder why GM stuck them in the '84's and '85's?

 

During a rebuild to run in the mid 6k RPM range are forged pistons an advantage?

 

Because of the raw, brute, hellacious power of the Crossfire. The '85's got them as leftovers.

There is no additional power in a forged piston, just ability to take a beating, namely from detonation.



NO! In a case like that, the use of forged pistons fall into the, "nothing is too good for my baby" category. It does more for the ego of the one paying the bill than it does for the car.

RACE ON!!!

 

The pistons from JE, Ross etc are very light weight. Also much stronger in the wrist pin area. This makes them worth the $$$ when you have a serious motor.

 

I like them cuz they clean up real good.

 

piston stops to zero speed and restarts twice for each crank revolution....''mean effective piston speed'' if you want techno-talk varies with rpm and length of stroke....with a 3.47'' stroke (sbc-1) the meps creates forces capable of yanking the wrist pin out of a factory (oem chev) cast piston at abt 5500 rpm ....aftermarket cast pistons MAY be good for a bit more...most forged pistons will hang onto the wrist pin for much higher revs.
most engines see detonation at some point...cylinder pressures can be several times normal when detonation occurs...higher strength of forged piston crown (top), ring lands, and wrist pin support may survive where a cast piston failure occurs

 

Okay, its fair to say, more rpm more stroke etc its just a good thing to have a stronger piston, as a forged is definitely stronger.

 

Same theory applies to connecting rods. Thay also come to a halt equally as hard. They try to tear themselves apart every time they stop. That is why most guys at least use an arp or wsb rod bolt in a stock rod.

 

I feel like one point a lot of people (the readers more than the posters themselves actually) are probably missing here, is that if you get detonation with forged or with hypers/cast, you are still gonna probably be hurting.

Now, does forged piston only damage itself in bad detonation?
Does a hyper/cast piston pop into tons of pieces to trash your motor?
Sure, both these things can be true, but detonation is bad either way.

Your job as the driver and maintainer is to keep that from happening, you fail with either piston it is still gonna suck.

That said, go with forged if you want to. Hell if I care. I wish I went with them so I could throw NOS or a S/C at them with less worry.

I don't know exactly how much of a difference oil burning wise it makes or how much whatever correlations you may see or not see are dependant on the installation and mftr. specs for setting the rings. I wouldn't choose my pistons based on a generalized statement but on a piston by piston basis.

Just don't think that running a forged means you can put TNT in your gas tank and still not hurt anything.

Also, the main point that I brought this up, is I see a lot of people with pistons in their motor. Is this due to their future plans to go bigger and with power adders? I can't say. But I just want the word out there, that people know, with forged pistons you can't really just hop in the car and go, you have to let the piston swell as mentioned above.

SO, to summarize:

1) if it is a TRUE weekend cruiser that you can let it idle for 10 minutes prior to driving, go forged no matter the power level, with a proper installation you get the ego power and the capabilities without much sacrifice.

2) if you need/want to be able to start up your car and drive it in a reasonable amount of time, go hyper if your power level isn't insane and you won't be going above 6500 much

3)Mo power, mo problems. Go forged if you are building a rev'r or a FI or a true hi-output motor. Save yourself the mental sweat but realize, it isn't the same and needs to be warmed before going out and nailing.

 

i have forged in my stroker.my builder recomended a nice light weight speed-pro forged racing piston. i did this more for piece of mind rather than anything else. if i want to give her a little more pwr later down the road i can. if not oh well i still got the piece the of mind. i look at it this way if your builder is reputable listen to him. i did cause why? he is way smarter and more experienced than me.

 

Are you able to start up your car and drive it or do you have to let it idle for a few minutes?

 

My builder on my 383 selected hyper pistons for it. He told me that for the power level I was running I would just be wasting money on the forged ones. He also said that hyper pistons get a bad rap because a lot of people install them wrong. Many older engine builders throw hyper pistons in with the same clearance as a forged piston and they beat themselves to pieces.

 

i never start it up and just run till it hits op temp. i also run val. #211 20-50 oil with zink additive

 

Speed pro makes a light-weight piston???

 

I've never heard of such a thing.

 

according to my builder yes. i didnt question it. he builds 200+ mph na and turbo corvettes. so what he said goes for me