Would you recommend a custom aluminum piston with Molnar rods or a forged piston? The goal is to set the compression ratio at about 9.2 to 9.35 for a mild turbo-charged (4-5 psi) build. The engine will not be raced.

Given the intended use, is there an advantage of one over the other? Disadvantage?

Does the use of forged pistons result in higher oil consumption and increase cylinder bore wear? The factory didn’t use forged pistons but also didn’t turbo-charge.

TIA

–Walt Jackson

Even forged Pistons are still aluminum.

Are the stock pistons aluminum?

--Walt jackson

Yes

_________________
2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

Most engine have used aluminum pistons since around the 1930s.

I think the question you are asking is whether to use cast aluminum or forged aluminum pistons.
All things being equal forged pistons are stronger and likely to be more durable.
On the other hand, the alloys used for most forged pistons expand more with heat than the alloys used for cast pistons.
Typically forged pistons need a little more cylinder clearance than cast pistons do.
So cast pistons can run quieter at cold startup. This makes them preferable for many OEM applications.
Forged pistons are also more costly to produce so if an OEM can get away with using cast it saves them money.

IMO, unless you are really going to be punishing those pistons it probably doesn't matter whether you go with cast or forged.

_________________
--> Check out my FI Turbo build <--
--> And the race truck build project <--
--> The Diesel Corvette <--

I'm using stock replacement cast type pistons, and I intend to run somewhat more than 5 psi of boost. If you have a good tune and keep it out of detonation, you'll be fine.

_________________
Matt Cramer
1966 Dodge Dart turbo / EFI project

As long as you will not allow the engine to get into detonation (spark preignition), then cast stock replacement pistons will be just fine. 4-5 psi is not much boost in terms of taxing the engine, but it will make a lot more power (50-100 HP). I like your idea.

I like Silvolite pistons, or I think Enginetech or Zollner or Badger or Mahle or Sealed Power pistons would be good. Just do not buy the cheapest piston you can find with some no-name brand... I recommend 0.040" or 0.060" overbore.

Have fun!

Lou

_________________
Home of Slant6-powered fun machines since 1988