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Old 03-12-2013, 06:24 AM   #1
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Default What piston/compression rate to run on a begi kit

Hi so I picked up a 94-95 1.8 motor and I stripped it planning on a turbo build. My power goal is anywhere between 250-300, and I planned on running forged rods and supertech pistons. I want the motor to be reliable and easily handle that amount of boost without failure. For the most part I also plan on DDing the car, as stupid as it sounds.

I was looking into the begi kit that comes with the garrett 2560r, but what I don't know is what compression rate to use. I talked to some turbo people and they have told me that using 8.6:1 compression with the right turbo could easily put me to 300. I'm aware that the 2560 turbo isnt the largest turbo, and from what I know higher compression = quicker spool, but less boost, and low comp = more boost. So basically I'm stuck in between 8.6:1 and 9.0:1.

The reason I want to use a kit turbo is because I just want to be able to just put everything together and not really be missing anything. In fact I'm getting some people telling me that forged internals and my power goals are a little much, but I don't believe so and I believe in building for reliability.

I'm still learning (I came from mostly n/a) and I've been doing a lot of reading to try to learn, so some patience would be appreciated
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Old 03-23-2013, 03:11 PM   #2
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Quote:
Originally Posted by Savington View Post
He's saying that the 8.6:1 motors produce more torque and have a greater safety margin than the 9:1 motors. You can run more timing on an 8.6:1 motor than a 9:1 motor, and the drop in compression and increase in timing advance produces more torque than running less timing and more compression.

Every single turbo motor we build is 8.6:1 for a reason.
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Old 04-05-2013, 09:47 AM   #3
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The first you should learn how to do is tuning.

Buy a MS, practice, tune, experiment all you can the car like it is before spending big bucks on parts, labor etc.

Many Civics/ Integras are running 300 and plus DDs on [email protected] (or higher), its all in the tuning.

The stock pistons can hold 300 hp, the weak link are the rods.
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Old 04-05-2013, 10:12 AM   #4
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No the FIRST thing you should do is learn to search.

Then learn to tune. Then turbo.
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Old 04-05-2013, 07:23 PM   #5
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Quote:
Originally Posted by mazpr View Post
Many Civics/ Integras are running 300 and plus DDs on [email protected] (or higher), its all in the tuning.
Irrelevant example. Our motors are not B/D/F/K-series motors, and they do not act the same.

OP, read post 2.
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Old 04-06-2013, 01:36 AM   #6
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Combustion chambers are very different so is cylinder filling and efficiency of manifolds.

TL;DR what sav said.

Your Stud kit is going strong BTW Andrew thanks mate

Dann
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Old 04-06-2013, 02:08 AM   #7
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8.6 or nothing.
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Old 04-06-2013, 02:57 AM   #8
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Your Stud kit is going strong BTW Andrew thanks mate

Dann
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