Magnum 5.9 piston crown thickness

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TT5.9mag said:
It’s just the intakes that I’m worried about as the valve size is a big step up from a stock magnum, 2.055 vs 1.88 stock. But I will for sure measure both when the time comes.
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Doesn't make any difference, but the stock valve should be 1.92, not 1.88.
 
Keep some interest in this thread and really the first time I’ve posted a pic of it. This is the almost complete mock up. Working on the hot side currently.
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DionR said:
Info on the alternator mount?
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Drag and drive car so I needed parts that are easy to get, hence GM LS alternator. Everyone in the pits will have a spare. The mounting for it and the idler is all homemade by me.
 
TT5.9mag said:
Drag and drive car so I needed parts that are easy to get, hence GM LS alternator. Everyone in the pits will have a spare. The mounting for it and the idler is all homemade by me.
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Makes sense. Looks like a slick setup, I like it.
 
DionR said:
Info on the alternator mount?
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Close up pics. Some flat stock bent, some 3/8” DOM for spacers, a turnbuckle made from the same DOM and some old heims, and an idler pulley that was 3 or 4 pulleys from various different engines all rolled in to an alternator mount. Oh and I had to turn a spacer on the lathe to get the 7 rib pulley on the Delphi alternator.
 
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I also had a good conversation with Mike at B3 yesterday and my rocker stands are done, payed for, and shipped. I should have everything but pushrods early next week.
 
TT5.9mag said:
View attachment 1716278122
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Close up pics. Some flat stock bent, some 3/8” DOM for spacers, a turnbuckle made from the same DOM and some old heims, and an idler pulley that was 3 or 4 pulleys from various different engines all rolled in to an alternator mount. Oh and I had to turn a spacer on the lathe to get the 7 rib pulley on the Delphi alternator.
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Very cool!

The spacer won't cause problems if you have to grab a different alternator on a drag and drive event?
 
DionR said:
Very cool!

The spacer won't cause problems if you have to grab a different alternator on a drag and drive event?
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No I didn’t modify the alternator or the pulley at all. It will all bolt on to any Delphi cs130 alternator.
 
Mmagnum engines have a quench pad on the heads. To determine detonation, it is best to keep piston to head clearance down to 0.040" or even 0.035", depending on con rod construction, piston compression height, and how high you intend to rev the engine.
Quench or in Europe, squish, promotes mixture motion, which aids a quick and efficient burn. With that in mind, view David Vizard Powertec 10 videos Ep 148 to 150. He also discusses piston porting in his Chevy Big Block, Max Performance on a Budget book.
I think I would be looking for pistons to zero deck it. DV builds many engines with the pistons 0.005" proud of the deck.
 
TT5.9mag said:
Ok ok, I’m doing something weird. I’m putting w2 heads with 2.055 valves on a stock bottom end magnum 5.9 shortblock with a mildly aggressive hydraulic roller cam and twin turbos. As we all know (I hope) lift has nothing to do with piston to valve clearance, it’s the duration and ramp rates that get the valve in to the piston. Myself and Brian at IMM (he did my heads) are not sure if we’re going to have clearance On the stock piston with no valve reliefs. Even with a huge dish, the valves will hit on the outer edge of the flat portion of the top of the piston. I’m currently waiting for my blocks and relocation kit from Mike at B3 racing and then I can measure for pushrods and check P to V. It’s gonna be close.
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You are intending to run stock pistons with twin turbocharger? Are we going to place bets on how many runs up the strip before the pistons move to the oil pan?
 
TT5.9mag said:
Yea I know how to measure for it. I’ve mocked it up a bunch already and and it’s very close with the cam in at 109.5, it won’t have more than .020 on the intakes right at the edge of the dish. Before I got too crazy I wanted to know how thick the crowns were and how much they’d need cut.
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Now I see why the fairly large deck clearance, turbos. Where that little nick is in the side of the dish, you want to lay that back about 1/4" following the outer diameter of the valve cutout, from that nick up to the crown.
 
Dale Davies said:
Mmagnum engines have a quench pad on the heads. To determine detonation, it is best to keep piston to head clearance down to 0.040" or even 0.035", depending on con rod construction, piston compression height, and how high you intend to rev the engine.
Quench or in Europe, squish, promotes mixture motion, which aids a quick and efficient burn. With that in mind, view David Vizard Powertec 10 videos Ep 148 to 150. He also discusses piston porting in his Chevy Big Block, Max Performance on a Budget book.
I think I would be looking for pistons to zero deck it. DV builds many engines with the pistons 0.005" proud of the deck.
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I’m well aware of the quench pad on the stock mag heads and the benefit of running the clearance down tight. Those heads are long gone and this engine now has open chamber W2 race heads on it. Chamber size and deck clearance has been carefully thought out to achieve my goals using the parts the stock bottom end of the magnum already has. I’m not looking for pistons because I’m using the stock piston, that’s what’s being discussed in this thread.
 
Dale Davies said:
You are intending to run stock pistons with twin turbocharger? Are we going to place bets on how many runs up the strip before the pistons move to the oil pan?
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Please do. I intend to find the limits of the stock magnum parts. I’m confident in my tuning abilities and a part failure will be just that, a failure of a part rather than a tuning mishap.
 
TT5.9mag said:
I’m well aware of the quench pad on the stock mag heads and the benefit of running the clearance down tight. Those heads are long gone and this engine now has open chamber W2 race heads on it. Chamber size and deck clearance has been carefully thought out to achieve my goals using the parts the stock bottom end of the magnum already has. I’m not looking for pistons because I’m using the stock piston, that’s what’s being discussed in this thread.
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Got it. Detonation can be an issue. You may want to look into H2O injection.
 
Dale Davies said:
Now I see why the fairly large deck clearance, turbos. Where that little nick is in the side of the dish, you want to lay that back about 1/4" following the outer diameter of the valve cutout, from that nick up to the crown.
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That piston was merely a test. If I have to cut the pistons I’m using, they will get softened after fly cutting.
 
Dale Davies said:
Got it. Detonation can be an issue. You may want to look into H2O injection.
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Nope. I hate water injection. I’ll be on e85 so likely won’t have a problem and if I have to supplement octane I will inject straight methanol.
 
Update, I got the rocker stands from Mike at B3 racing. @B3RE you do an exceptional job, thank you, the stands are beautiful. I’ll have pics later. I changed the adjusters in my crane gold race rockers from ball to cup, and measured for pushrods. Ordered those last night from summit. Comp had a 7.150 so I didn’t have to have them made. I’ll have those, and my turbos (enter happy face here) tomorrow.
 
Couple pictures for updates.
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Rocker stands, shafts and rockers, thanks to two members @Rocket for the shafts, and @B3RE for the stands.
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And some mirror image 67mm goodness.
 
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