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MTI stage 2E head E/I port ratio....

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Old 03-26-2005, 09:17 AM
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Default MTI stage 2E head E/I port ratio....

well, i just installed my stage 2e heads and stealth 1 cam a few weeks ago. now im kinda regretting not going with a split pattern cam. i calculated my E/I port ratio, and the exhaust flow at .600 lift is only 69%. i was hoping for more like a 75-80% ratio. so anyway, will a cam with a longer exhaust duration/higher lift compensate for the exhaust port's lacking air flow?? i was set on the G1 cam (228/232 .588/.575 113lsa) when i first ordered my heads, but then i decided to go the stealth route for a "sleeper" car. man i am kicking myself in the *** for that anyway, i kinda wanna swap cams now....i just wanted to know if this would be a good idea. opinions/suggestions??
Old 03-26-2005, 09:43 AM
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Yes, a cam can make up for a cylinder heads weakness by timing events cut into the cam. That is part of the advantage of having a custom cut cam. Try the 232/234 XE-R Comp also
Old 03-26-2005, 09:46 AM
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You need to stop looking at the flow at .600 lift. You're not running a .600+ lift cam. Look at the flow numbers at .300, .400, and .500". Plus, you need to remember that bolting up the stock intake will knock those intake flow numbers down, while your headers will bring the exhaust flow numbers up. See, MTI doesn't publish exhaust flow numbers with a pipe like other MFRs. Don't sweat the cam choice. Your intake to exhaust ratio is probably right at 75-80% with everything bolted up.
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Old 03-26-2005, 10:05 AM
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hmm....actually when i look at the lower numbers, youre right. it is closer to 75%. i still kinda wanna get off this stealth thing though. i will have this car paid off within a year and it will no longer be my daily driver. so i will be able to give up a lil bit of driveability. though i still wanna keep it pretty streetable. anyway, thanks for the wake up there
Old 03-26-2005, 10:11 AM
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I look at average flow numbers myself. Like mine average from .200" to .600" 222cfm on the intake and 162cfm on the exhaust w/o a pipe so that would be 72.9%.




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