high comp ka24

[Russell]

I'm building a high compression ka24de i have ka24E pistons so compression will be around 11:1 or 11.6:1 

I am wonder if i should gap the ring a little loose than spec because if the extra heat i will be making. spec is .0110-.0205

 

[datzenmike]

I get 11.1 but I don't have an exact combustion chamber size for the DE head. I reverse engineered it to 47cc and ran my calc at 46cc. Do you have the correct size???

 

N/A top ring gap? 0.004" for every inch of bore so on a KA that's 0.014". Drag or track racing is 0.0045" per inch or 15.77" I wouldn't go that wide Maybe just under 0.0145" as a compromise. Fourteen thou will be fine for all over running and good compression

[Russell]

It's a stock DE head (I used 46cc for measurements) it hasn't been decked the 89-early90 ka24e Pistons gave me 11.6:1 and the late90-94sh gave me 11.0:1. Compression ratio doesn't matter to much right now for me, but I bought aftermarket stock Pistons and it said (89-94sh ka24e) Pistons so I don't know which ones they are.

[datzenmike]

The later 8.5 compression E pistons have a small 2.8cc dish. Here's mine...
 

 

 

The early 9 to 1 compression pistons were used for only three months. I have to assume they have a small dome on them. If you do indeed have these please post a picture of them.

[Russell]

I think my compress will be even higher because they don't even have a dish there just flat tops. I'll get some pics up in a few mins here.

[DISLEXICDIME]

You have early pistons

[Russell]

 

nevermind there are dished, thats the first time i've looked at them in bright light before

[ggzilla]

So stock block (not decked), stock head, and stock pistons ... I predict it will have stock compression.

[Russell]

So stock block (not decked), stock head, and stock pistons ... I predict it will have stock compression.

these are ka24e pistons going into a ka24De blocks compression should be around 11:1 

[datzenmike]

Yes, the E head is about 67cc while the DE head is about 46cc. Using E pistons (above) will make about 11.1

[Russell]

and for the second compression ring what should i gap that to, I know it needs to be bigger than the first ring

[ggzilla]

Drag racers and SCCA racers often run 14:1 compression, so that large ring gap mike mentioned probably doesn't apply.

 

11:1 is used by many modern cars, and they don't have unusually extra large gaps.

[Russell]

Drag racers and SCCA racers often run 14:1 compression, so that large ring gap mike mentioned probably doesn't apply.

 

11:1 is used by many modern cars, and they don't have unusually extra large gaps.

this motor will also see boost some day.

[DISLEXICDIME]

I hope you're planning on using race gas if you're going to boost a 11.1.1 ka k a stock pistons don't like boost at stock compression rate

[Russell]

i have a VF40 off a Subaru I'm gonna run 5 lbs on for learning purposes, i want to experiment with E85 and water meth, this motor could grenade on first start up and i wouldn't care less.

[datzenmike]

I wouldn't worry about the rings. The DE uses oil jets to cool the pistons so add an oil cooler, it'll be fine.

[Russell]

ok will do thanks for such a quick response mike, I'm really starting to like this form more 

[Tristin]

ok will do thanks for such a quick response mike, I'm really starting to like this form more

Post plenty of pictures and have a thick skin. It's all you need to know... There's tons of knowledge here. Stick around and post more about your build.

[Russell]

I'll start a build thread soon, and as long there aren't any death threats I be in for the long run