Optimal compression ratio for boost? - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

JantzenOKC · 10-01-2015, 03:19 PM

Well since I'm down a motor and the racing season is almost over here anyway, I'm thinking about building a forged motor. What does everyone think the best compression ratio would be for the LFX with twin turbos? Since I would be getting a custom set of pistons made, I could probably make it whatever I wanted. I know Gretchen had some made and was at 10:1 but I don't know if I would really need to be that low or not since we have direct injection. I remember him saying it was missing a little power when not in boost. I wonder if he could do it over again if he would have still went with 10:1 or would he have went a little higher..

Thoughts?

smithnc · 10-01-2015, 03:30 PM

Ecoboost is 10.0:1 as well... you'd probably be good there or maybe 10.5:1.

its a syn · 10-01-2015, 03:35 PM

Subscribed to this build! Good Luck!!

Jason@JacFab · 10-01-2015, 06:12 PM

I know your girlfriend probably doesn't approve of this... LOL!

I can tell you that the LF3 is 10.2:1, as well as the LF4...

I know you were asking about LF4 rods, but I have a set of LF3 rods here. The LF3 rods are shorter than the LFX rods. I would imagine that the LF3 and LF4 rods are the same length. Doesn't really matter too much if you're going to have custom pistons made anyway.

JantzenOKC · 10-01-2015, 07:41 PM

Quote:

Originally Posted by smithnc

Ecoboost is 10.0:1 as well... you'd probably be good there or maybe 10.5:1.

Yeah I was thinking 10.5 might make more power and still be ok since we're DI. Especially if I end up adding a meth kit to it. But I'm not an expert and 10:1 might be the wiser choice.

JantzenOKC · 10-01-2015, 07:41 PM

Quote:

Originally Posted by its a syn

Subscribed to this build! Good Luck!!

Thanks I need some luck!

JantzenOKC · 10-01-2015, 07:46 PM

Quote:

Originally Posted by Jason@JacFab

I know your girlfriend probably doesn't approve of this... LOL!

Oh man, we're just not gonna tell her much. Just that the cars broken and i have to build a motor for it lol. I need to go ahead and do it while she's still the girlfriend and not the wife!

HP Turbine · 10-01-2015, 09:00 PM

She is going to kill you. But at least you would have a built motor. I wish you the best of luck. If you do well you can start a lfx forge shop

10-01-2015, 03:19 PM	#1
JantzenOKC Drives: '13 2LT/RS Twin Turbo Join Date: Aug 2012 Location: Edmond, Oklahoma Posts: 3,073	Optimal compression ratio for boost? Well since I'm down a motor and the racing season is almost over here anyway, I'm thinking about building a forged motor. What does everyone think the best compression ratio would be for the LFX with twin turbos? Since I would be getting a custom set of pistons made, I could probably make it whatever I wanted. I know Gretchen had some made and was at 10:1 but I don't know if I would really need to be that low or not since we have direct injection. I remember him saying it was missing a little power when not in boost. I wonder if he could do it over again if he would have still went with 10:1 or would he have went a little higher.. Thoughts? __________________ 3.6L Twin Turbo V6 Garrett GT28 turbos -- Jacfab forged connecting rods -- Diamond forged pistons(10.5:1) -- Alky Control Methonal Injection -- CircleD 2E triple disc torque converter -- BMR suspension 10.75 @ 131mph

10-01-2015, 03:35 PM	#3
its a syn B.O.D. 02/16/10 Drives: 2010 SGM Sp. Edition 2017 RS Conver Join Date: Jun 2010 Location: Albia,Iowa Posts: 3,959 View My Garage	Subscribed to this build! Good Luck!! __________________

10-01-2015, 09:00 PM	#8
HP Turbine Boosted Drives: 2012 1LT RS... with snails Join Date: May 2012 Location: New Hampshire Posts: 1,455 View My Garage	She is going to kill you. But at least you would have a built motor. I wish you the best of luck. If you do well you can start a lfx forge shop __________________ IPS Twin Turbos, Corsa Exhaust, Ported Throttle Body. 461 rwhp 443 rwtq!! Cameron Hass.ani

10-01-2015, 03:30 PM	#2
smithnc Drives: 2012 Camaro RS Join Date: Jun 2013 Location: Colorado Posts: 208 View My Garage	Ecoboost is 10.0:1 as well... you'd probably be good there or maybe 10.5:1.

10-01-2015, 06:12 PM	#4
Jason@JacFab Drives: 2016 1LT RS Camaro; 72 Chevelle Join Date: Apr 2008 Location: Central Point, OR Posts: 5,688 View My Garage	I know your girlfriend probably doesn't approve of this... LOL! I can tell you that the LF3 is 10.2:1, as well as the LF4... I know you were asking about LF4 rods, but I have a set of LF3 rods here. The LF3 rods are shorter than the LFX rods. I would imagine that the LF3 and LF4 rods are the same length. Doesn't really matter too much if you're going to have custom pistons made anyway.