A.I. 21* HCI package
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A.I. 21* HCI package Well ive decided to pull the trigger and build AI 355. With the 21* heads can you run SA rockers? I imagine they mill the intake so all the runners line up when you get the package?
Would my SVO red tops be plenty injector for this combo?
Would my SVO red tops be plenty injector for this combo?
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I imagine this package would make 420ish rwhp. Injectors are 31.6 lbs with lt fuel pressure. And the reason i asked about the rockers is i already have comp ultra mags sa. I spin to 6800+ plus all the time with this combo and no issues.
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If you ask me you're asking for trouble. Walking a rocker is not good at all. I would just sell the rockers and get chromoly pushrods and guide plates and new rockers. Its cheaper insurance.
TFS chromoly pushrods are 100. Guide plates are like 30 bucks.
Those are two small. Get some 42lbs. Will give you some room to play with.
At 43.5psi 500bhp .5 BSFC you would need ~39lbs at 80% duty cycle. So 42s would give nice head room.
Those injectors would be at 100% duty cycle at 500bhp.
A 42 will be at 75%.
TFS chromoly pushrods are 100. Guide plates are like 30 bucks.
Those are two small. Get some 42lbs. Will give you some room to play with.
At 43.5psi 500bhp .5 BSFC you would need ~39lbs at 80% duty cycle. So 42s would give nice head room.
Those injectors would be at 100% duty cycle at 500bhp.
A 42 will be at 75%.
Last edited by F0x Slaughter; Apr 8, 2012 at 05:09 PM.
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Sounds like a plan ill get some nsa rockers. I have trickflow pushrods already if they are the proper length. Ill prob sell my motor to offset some of cost. What injectors are people having luck with?
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Stock Eliminator cars are interesting to learn about but that does not mean it all translates to what the rest of us are doing, they spend a lot more to go fast with a lot "less".
While I know he does get away with such performance on such small injectors I believe the whole fuel system comes into play, not even just the pressure.
While I know he does get away with such performance on such small injectors I believe the whole fuel system comes into play, not even just the pressure.
My stock cube H/C build had no problems at all with 30# SVO injectors. Its not a brick wall or end of the world at 80% duty cycle.
It's not like decades ago where injectors can't spray a proper pattern after 80%, modern injectors can still maintain a proper pulse at higher duty cycles.
It's not like decades ago where injectors can't spray a proper pattern after 80%, modern injectors can still maintain a proper pulse at higher duty cycles.
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They will maintain the pattern but you have no room to grow. Plus it has a change of overheating the injector and could stick open. This is why you try to keep the injector around 80% cycle. So they don't fry. Use them in a pinch sure, but you want to properly size your injectors for your engine, just like a turbo. When you build a house do you go eh f code it will be to much money, or do you go lets build this to or beyond code because it will last.
Time to get out of the 13 sec club! 
