What CR for 408 w/F1
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I've been thinking 8.5.1 to 9.5.1! Lots of guys are telling me to go as high as I can with the compression so I don't have to run lots of boost. This will be my first FI build so everything is new. Any help would be great. What fuel system do you run? How much power do you make? What boost? Thanks
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I'm at 9.4:1 with a 408 F1R... Go 9:1 or a little more with an average cc head (67 or so) and should you choose to run more boost and less compression in the future, you can get down to 8.6:1 by simply changing to a set of 72cc heads... ie: keep your options open without having to get into the shortblock.
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I am 408 and went with 9.5 to 1. Plan on running alc injection all the time and car is street car. Possibly e85 when it becomes available here..if it becomes available here!
Wanted a bit more snap off boost and more compression pretty sure helps it spool up quicker. 9.1 seems like a nice middle ground and 8.5 is pretty common on cars that see huge boost and the track a lot. I am hoping to hit around 800 on auto or 850 rwhp on m6 with my setup at maybe 15psi.
Wanted a bit more snap off boost and more compression pretty sure helps it spool up quicker. 9.1 seems like a nice middle ground and 8.5 is pretty common on cars that see huge boost and the track a lot. I am hoping to hit around 800 on auto or 850 rwhp on m6 with my setup at maybe 15psi.
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Alot of people tend to agree on 9:1 , the extra .5 wont gain a huge amount of power. If your looking for a snappier throttle response, then you most likely need a better cam or your have mixed matched componets.
For a bigger boosted car for pump fuel (~800rwhp) 9:1 is ideal, the added compression may lessen the amount of safe hp due to not running race fuel.
The turbo guys have been doing this for a while, low compression + high boost.
Eithe way, consult your engine builder to see what they recommend.
For a bigger boosted car for pump fuel (~800rwhp) 9:1 is ideal, the added compression may lessen the amount of safe hp due to not running race fuel.
The turbo guys have been doing this for a while, low compression + high boost.
Eithe way, consult your engine builder to see what they recommend.