# Turbo and comp ratio

**URL:** https://forums.speedlife.net/t/turbo-and-comp-ratio/102358
**Category:** SON240sx Automotive
**Created:** [December 9, 2006, 5:10pm UTC](https://forums.speedlife.net/t/turbo-and-comp-ratio/102358 "2006-12-09T17:10:07Z")
**Posts on this page:** 4
**Page:** 1

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### Author: ![krgoodwin](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/krgoodwin/32/5559_2.png) [@krgoodwin](https://forums.speedlife.net/u/krgoodwin)
#### Post date: [December 9, 2006, 5:10pm UTC](https://forums.speedlife.net/t/turbo-and-comp-ratio/102358/1 "2006-12-09T17:10:07Z")

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puting SOHC pistons in a DOHC block will raise compression. so logicaly putting DOHC pistons in a SOHC block will lower it. would this be a good idea when turboing a KA? with the low compression ratio it would make less power but be more reliable, no?

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### Author: ![scribbles](https://avatars.discourse-cdn.com/v4/letter/s/bb73d2/32.png) [@scribbles](https://forums.speedlife.net/u/scribbles)
#### Post date: [December 9, 2006, 10:37pm UTC](https://forums.speedlife.net/t/turbo-and-comp-ratio/102358/2 "2006-12-09T22:37:24Z")

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why would you want to turbo an E motor ?

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### Author: ![krgoodwin](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/krgoodwin/32/5559_2.png) [@krgoodwin](https://forums.speedlife.net/u/krgoodwin)
#### Post date: [December 9, 2006, 10:38pm UTC](https://forums.speedlife.net/t/turbo-and-comp-ratio/102358/3 "2006-12-09T22:38:17Z")

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really, i dont. just wondering.

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### Author: ![DarkForceJackal](https://avatars.discourse-cdn.com/v4/letter/d/b38774/32.png) [@DarkForceJackal](https://forums.speedlife.net/u/DarkForceJackal)
#### Post date: [December 10, 2006, 6:03am UTC](https://forums.speedlife.net/t/turbo-and-comp-ratio/102358/4 "2006-12-10T06:03:51Z")

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There’s nothing wrong with turbo’ing a SOHC motor as it is (providing it has good compression numbers and is in decent shape).

However, I wouldn’t bother changing to DOHC pistons. I’d say leave it as it is for lower boost levels, or rebuild with forged pistons/rods etc for higher boost.

There are much more important factors to a KA-T’s reliability than that, such as proper and careful installation of parts, good clutch and braking systems, good & clean motor oil, gasoline octane & timing, your fuel system and/or tuning, using a good & preferably new turbo, good manifold, and what not else.

Have a look around the SOHC KA-T section on [http://www.ka-t.org](http://www.ka-t.org) for some more good info.

Cheers.