I am about to rebuild my engine, right now I am looking for a set of Piston and all the stuff that need to be change(gaskets ,etc), first of all I want to go with a set of custom Forged Piston. I am still calcuating the compression ratio for my enigne , I got a FSM , but I don't see the spec that I need (I need them in order to calcuate the compression ratio) . what I need is
1. Stock headgasket thickness?2. Head ( cc )3. Deck Height (in)4 Dish or Valve Pocket [-] or Dome [+] (cc) I want it to be 8.1 - 8.3 Compression ratio ? what would 3.50 bore X 3.48 stroke come out to be ,any other ppls' have a custom piston setup? ? thanx
Time to rebulid my KA , need some spec for the engine
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deviousKA
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1. Noted in various places to be .047" crushed, ones i have measured (stock crushed) have measured closer to .040".2. ka24de 45cc, ka24e 65cc 3. 247mm (9.72441")4. De pistons roughly 11.2-12cc dish volume, Late ka24e pistons 2cc dish, early ka24e pistons 2cc dome.
for 8.1 CR in ka24de you will want pistons with ~28 cc dish volume using stock compression ht for piston (34mm).
Thats a major dish, it would be better to go with pistons with much lower compression ht. So there are quite a few combos to go with, something like a 31mm compression ht, 8cc dish would work. This is for 8.1-8.3:1 in ka24de
If its a ka24e, you will need pistons with stock compression ht, and a 9-7cc dish. Or flat tops with a 32.5-33mm compression ht.
This is only a basic guideline, there are many different combos in between.
for 8.1 CR in ka24de you will want pistons with ~28 cc dish volume using stock compression ht for piston (34mm).
Thats a major dish, it would be better to go with pistons with much lower compression ht. So there are quite a few combos to go with, something like a 31mm compression ht, 8cc dish would work. This is for 8.1-8.3:1 in ka24de
If its a ka24e, you will need pistons with stock compression ht, and a 9-7cc dish. Or flat tops with a 32.5-33mm compression ht.
This is only a basic guideline, there are many different combos in between.
I have a Ka24de, First I have a thought to to use some other piston off from other car, like Chevy 267 3.50 X 3.48 or bigger bore and reduce stroke 3.552 X 3.542, I am still reseaching what kind of pistons would fit the Ka24DE , othewise I will use the one from JE ROSS Arais whichever fit my application. I only have rebuild a few engine with the stock component before, never try something else, so this is actually my first time..I heard ppl's had done it( use different piston on the KA ) so . however, please let me know how to lower the compression ratio , would reduce stroke lower the compression?