I am building a street slant with Molnar 7.005 long rods. Are the Keith Black KB239 pistons still a good choice? They have wrist pin retainers for the full floating pin. My heads are 60cc, so this setup should give me 9.88:1. I'm using a bigger than stock Oregon regrind. It is port injected with a knock sensor. I don't mind using premium fuel.

Are those pistons cast or forged?

Do they have valve reliefs? (you likely will not need them) Is this an N/A engine or boosted / sprayed with nitrous?

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http://www.youtube.com/hyperpack

NA. No nitrous. Cast aluminum. Hypereutectic This my Mazda RX-8 that I have been working on for 4 years. Just a fun project. No racing. Just local parking lot car shows. Dutra Duals, Gill Welding port injection intake, Gill Welding exhaust, Haltech ECU, LS coils. Just something for me to inker with. I have a local engine builder building the engine. Boring to 3.445" 87.5 mm. Money is not a consideration. The KB239 plus the 7.005 rod gives me a zero deck. The modern pustons are lighter to rev a bit higher and have thinner rings for less friction.

Why not use the Wiseco "forged" pistons Price is about the same when you consider the Wiseco pistons come with the rings, and the KB pistons do not come with rings. Granted with the KB's you will have two spare pistons.
https://www.campbellenterprises.com/sla ... istons.php

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Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 170 nitrous
64 Valiant Signet
64 Valiant 4dr 170
64 Valiant 4dr 225

Yes to what Charlie said. Forged pistons cover you for anything in the future too. Especially if money is not an issue.

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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

Agree with Charrlie and Rick.

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http://www.youtube.com/hyperpack

How bad do the forged pistons rattle when they are cold?

My opinion. If the engine is bored/honed to match each piston with the proper clearance, you might hear a slight rattle for a minute or two. But most time, with the exhaust noise and/or radio, you will not even hear it.

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Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 170 nitrous
64 Valiant Signet
64 Valiant 4dr 170
64 Valiant 4dr 225

Guys, thanks for the input. I'm going to go with the Keith Black pistons. I'm never going to boost or use nitrous. I want the car to be as quiet as possible. Everything I have been able to read says that cast is fine and Keith Black is a step up. My car will have a knock sensor, so I'm not worried about detonation. The car weighs 3,000 pounds. I don't think it will ever detonate.

Should work great. You can make plenty of power with cast pistons.

Lou

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