EFI head vs Non EFI head?
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From: Casa Grande
EFI head vs Non EFI head?
Ok, I was down at a friends shop talking about waking up the 300 and maybe getting a little better MPG. He said he would recommend starting with an EFI head for it's better flow already then do a mild PnP. It kinda maked sense to me but have never heard anyone talk about the EFI heads flowing any better. Anyone heard about the head flowing better? If I were to do it it would be mostly for increased MPG, and little more power to.I know intake/exhaust, better gears and tires are needed to but was wondering about the head cam thing to.
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The EFI heads are the "fast burn" design. They accomplish this via the shape of the chamber, especially around the intake valve. They are also higher compression (smaller chamber). These two things together result in LESS flow on the EFI head because the intake valves are shrouded more than on the carb head.
In addition, the EFI heads are slightly thinner castings, and are a little more prone to cracking than the carb heads.
In addition, the EFI heads are slightly thinner castings, and are a little more prone to cracking than the carb heads.
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Joined: Mar 2008
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From: Near Los Angeles
The EFI heads are the "fast burn" design. They accomplish this via the shape of the chamber, especially around the intake valve. They are also higher compression (smaller chamber). These two things together result in LESS flow on the EFI head because the intake valves are shrouded more than on the carb head.
In addition, the EFI heads are slightly thinner castings, and are a little more prone to cracking than the carb heads.
In addition, the EFI heads are slightly thinner castings, and are a little more prone to cracking than the carb heads.
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From: Casa Grande
Well that does explain why I haven't read to much about using them. Thanks for the replies.That would probably be the last thing I get in to anyway. Running a 4sp/od trans and 31x10.50 tires I'm still showing 11% high on the odometer so figure rear gears must be around 3.50 or 3.73. Figure that would be the place to start for better MPG's. Only getting 13.77 now at 60-65.
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From: Casa Grande
I'm starting to think your right on the 4.10's The speedo is showing 11% higher than the GPS, 75 at about 65 on the GPS, and the 31" tires are approximately 11% bigger than the 215/75r15's it came with so that's 22% more gearing than the factory 3.31's. or 4.03's. Lot lower than I wanted.
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