Tall deck options

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
shannon said:
Ok so far guys I have bought a 6.535 connecting rod. I'm trying to find a piston (preferably a dome) to bring up my compression ratio to 10:1 - 11:1. Keep in mind I'm using the stock oval port 113cc heads. I'm not sure if they are open chamber or closed. It is written on the heads 366. #473328 on one head. #336781 on the other. Please keep it simple. I need to know what piston specs I need to find. Summit Racing and icon Pistons both have given me formulas but Fast talking leaves me confused. I understand my stock compression height is 1.765. I am getting conflicting information because one says my compression ratio will be close to 9:1. I don't know if that means flat tops or Dome. I have thought about getting the original L88 Pistons.I don know. I was told I should be able to use them and other passenger /performance Pistons because I've already made up the .400" difference by using 6.535 rod. Later on I plan on changing the heads to an upgrade. But I want to be able to have decent Pistons that clear the stock heads and valves. I say this with respect, you old timers should know the formula so I can then use it to figure out what piston I can use whether it be flat top or Dome. Again please keep it simple. I am not building a stroker engine. I'm building a 427 tall deck engine with a 550 lift cam. Thank you for your time.......again.

with a tall deck block deck at 10.2" and a 3.76" stroke crank and a 6.535" connecting rod
td6535.png

pist427.png

remember deck height 10.2"
minus rod length, 6.535"
minus 1/2 the crank stroke length 1.88"
equals the piston compression height. 1.785"


this is an excellent example of why doing the math before you purchase parts is so important

td425.png

td4inch.png


td68.png


http://www.enginebuildermag.com/201...ton-compression-height-and-crankshaft-stroke/
deckh.jpg

deckh.png



https://www.uempistons.com/index.php?main_page=calculators&type=piston_comp

http://garage.grumpysperformance.co...tall-deck-engine-mods.14632/page-2#post-78510

http://garage.grumpysperformance.com/index.php?threads/can-you-plan-for-quench.11298/

http://garage.grumpysperformance.com/index.php?threads/casting-numbers-vin.93/#post-29340

336781.....73-85...oval...OPEN...454, 118cc chamber, 256/114cc ports

473328.....68-69...oval...OPEN...366T
a few related and useful threads,
http://garage.grumpysperformance.co...gine-to-match-the-cam-specs.11764/#post-55571

http://garage.grumpysperformance.co...y-in-building-a-good-engine.11682/#post-54682

http://garage.grumpysperformance.com/index.php?threads/finding-a-machine-shop.321/#post-3007

http://garage.grumpysperformance.com/index.php?threads/a-few-calculator-links.7108/#post-27382

http://garage.grumpysperformance.co...on-picking-a-shop-to-do-work.5053/#post-28837

http://garage.grumpysperformance.com/index.php?threads/precision-measuring-tools.1390/#post-52469

http://garage.grumpysperformance.com/index.php?threads/types-of-crankshaft-steel.204/#post-15727

http://garage.grumpysperformance.co...ket-race-not-transportation.14229/#post-72588

http://garage.grumpysperformance.co...in-height-compression-height.5064/#post-66240

http://garage.grumpysperformance.co...ing-parts-and-a-logical-plan.7722/#post-51341

http://garage.grumpysperformance.co...onnecting-rod-rod-length-too-stroke-info.510/

http://garage.grumpysperformance.com/index.php?threads/maximizing-piston-to-bore-ring-seal.3897/

http://garage.grumpysperformance.co...ng-combustion-chambers.2630/page-5#post-82766

http://garage.grumpysperformance.com/index.php?threads/tall-deck-options.14678/#post-79151
 
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