 Deck height, compression ratio, and valve relief flat top pistons, In a 2.0 |
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| emerygt350 |
 Jul 13 2023, 11:41 AM
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Advanced Member  Group: Members Posts: 2,096 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States  |
Ok, my question of the day:
Put my new 96mm pistons and cylinders on and measured deck height, .033 all the way around. Let's say .032 to be conservative. I will not be running head gaskets. The calculator gives me 8.8 CR at .033 8.6 CR at .043 8.4 CR at .053 The pistons have a valve relief (pretty large) cut. I am shooting for 8.4 CR. Heads are in the shop so I can't check the CC yet. Everything I read says .04 - .06 for deck height. With the valve relief do I need to worry about going lower? If I had dishes would you measure from the edge of the piston or the dish? |
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Posts in this topic
emerygt350 Deck height, compression ratio, and valve relief flat top pistons Jul 13 2023, 11:41 AM
Montreal914 Not sure I understand how you can establish the CR... Jul 13 2023, 12:13 PM brant You have to measure the head volume to get compres... Jul 13 2023, 12:16 PM rfinegan O.040 deck height is considered the minimum deck h... Jul 13 2023, 12:31 PM emerygt350 Thanks Finegan, that's what I am looking for.... Jul 13 2023, 12:42 PM emerygt350 Very interesting read. Reminds me of why I rarely... Jul 13 2023, 01:13 PM Jack Standz For what it's worth, our 2056 had pistons wit... Jul 13 2023, 01:53 PM
emerygt350
For what it's worth, our 2056 had pistons wi... Jul 13 2023, 02:19 PM rfinegan A tip on piston to valve clearance.
The closest ... Jul 13 2023, 03:25 PM technicalninja Normal engines require .080 on intakes and .100-.1... Jul 13 2023, 03:47 PM emerygt350 Heads are back. They measured 55 CC but I am goin... Jul 20 2023, 02:47 PM rfinegan With stock valves and what cam are you using? The ... Jul 20 2023, 04:16 PM emerygt350 Yeah. All stock but the piston/sleave combo. I go... Jul 20 2023, 04:28 PM emerygt350 Did a real thorough job on the deck height today. ... Jul 21 2023, 01:29 PM Jack Standz
Did a real thorough job on the deck height today.... Jul 21 2023, 11:24 PM 930cabman
Did a real thorough job on the deck height today... Jul 22 2023, 05:30 AM emerygt350 Couldn't stop thinking about it, so I swapped ... Jul 21 2023, 02:43 PM rfinegan Yes moving the cylinders around may help. Those d... Jul 21 2023, 03:33 PM emerygt350 I bet that is contributing. I didn't really c... Jul 21 2023, 03:53 PM rfinegan here is how I did it..
https://www.youtube.com/wa... Jul 21 2023, 04:00 PM rfinegan As far as rock , I would think if measured across... Jul 21 2023, 04:03 PM rfinegan yes look like 8.0 to 8.2 will work nice on pump/pr... Jul 21 2023, 04:11 PM emerygt350 I have the rings in but there is still quite a bit... Jul 21 2023, 04:39 PM emerygt350 Everything seems nice and level on the case, no sa... Jul 22 2023, 05:59 AM emerygt350 Ok, redid them all using 4 bolts instead of two, e... Jul 22 2023, 10:27 AM rfinegan Woohoo..great Job! Just need the 0.030 shims ... Jul 22 2023, 12:37 PM emerygt350 That looks about right. Maybe while I wait for th... Jul 22 2023, 01:08 PM technicalninja .028 deck height on all four would make me want a ... Jul 22 2023, 01:46 PM emerygt350 These are hyper pistons. I am going with the .058... Jul 22 2023, 02:24 PM emerygt350 Decided to go about it differently. Play doh.
Sho... Jul 22 2023, 03:58 PM technicalninja I believe you are leaving 5-10 hp on the table wit... Jul 22 2023, 04:07 PM emerygt350 You are tempting me to go with .02 but since I am ... Jul 22 2023, 04:38 PM 930cabman "Leaving horsepower on the table" nobod... Jul 22 2023, 04:56 PM emerygt350 I mean, if I go with .02 that puts me at .048, tha... Jul 22 2023, 05:11 PM technicalninja .048 wouldn't bother me with forged but...
If... Jul 22 2023, 08:14 PM emerygt350 All good points, but I exceeded my budget on this ... Jul 23 2023, 05:19 AM emerygt350 Engine is going back together now. Ended up with ... Aug 11 2023, 03:32 PM emerygt350 RE: Deck height, compression ratio, and valve relief flat top pistons Aug 11 2023, 03:33 PM emerygt350 RE: Deck height, compression ratio, and valve relief flat top pistons Aug 11 2023, 03:34 PM 930cabman Exciting stuff
:Qarl: :Qarl: Go man go Aug 12 2023, 05:46 AM Shivers I’ve built three for mine and those three days w... Aug 12 2023, 06:04 AM  |
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