103 cylinder heads
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From: Clearwater, Idaho
Any twin cam '07-up head is going to be the same as your 103 heads. As far as the 110" heads, they have bigger combustion chambers, bigger valves, and stiffer (too stiff) valve springs. The 110" heads flow better too, but I'm not totally sure whether that is due mostly to the bigger valves, or due to bigger/differently shaped ports. I'm thinking it's both, though.
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From: Coal grove ohio 45638
Any twin cam '07-up head is going to be the same as your 103 heads. As far as the 110" heads, they have bigger combustion chambers, bigger valves, and stiffer (too stiff) valve springs. The 110" heads flow better too, but I'm not totally sure whether that is due mostly to the bigger valves, or due to bigger/differently shaped ports. I'm thinking it's both, though.
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From: deland,florida
out of the box 103" heads flow in the 225@28" area,110" heads around 275.when using 110 heads,it must be taken into consideration the chambers are from 95-98cc`s,so pistons must be used to bring the compression up to where most builds would need it to be.if going with 110 heads,i would recommend going 107" (as there are pistons made for 107"/110 head builds),also go with mild porting,2.100 intakes,a decent valve job (SERDI or ROTTLER) & bee hive springs
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From: Coal grove ohio 45638
103 heads
out of the box 103" heads flow in the 225@28" area,110" heads around 275.when using 110 heads,it must be taken into consideration the chambers are from 95-98cc`s,so pistons must be used to bring the compression up to where most builds would need it to be.if going with 110 heads,i would recommend going 107" (as there are pistons made for 107"/110 head builds),also go with mild porting,2.100 intakes,a decent valve job (SERDI or ROTTLER) & bee hive springs
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From: Coal grove ohio 45638
103 heads
and do you kno if the 110 heads can be decked far enough to bring the chamber cc's down to close to 103 stock size for a smaller quench ! Thank you.
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From: Coal grove ohio 45638
or would i be better off to jus port my 103 heads its a twin cooled ultra limited.
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From: Coal grove ohio 45638
103 heads
sorry i meant have them cnc ported . Thanks for the help an info
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From: san antonio
You can still maintain tight squench.
Last edited by djl; Aug 30, 2017 at 09:29 AM.
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