boost on stock cams and springs

Pedrothecobra

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well im back.... i finally opened up my motor and it was not bad but its not good lol. block is going to a machine shop this week to be checked out, was only planning on re-ringing this motor. but it looks like ill be building this now.

-provided the crank is able to be polished and the questionable cylinder can be bored out, i plan on going with a kit from MMR with all forged internals. i plan on pro-charging later down the road possibly next year provided i get this motor turned around in a decent time frame.

- how much boost/power can i run with stock cams and springs? im new to this game and im still learning. i couldnt find anything on the forums that answered this question.
- can i run stock cams and just beef up the springs? TIA
 

07GtS197

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Cams and springs don’t dictate boost. They compliment one another and can limit rpm. How much power do you want to make? With a built bottom end and a blower, even with stock cams, you can make more than enough power for a street car.
 
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Pedrothecobra

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Cams and springs don’t dictate boost. They compliment one another and can limit rpm. How much power do you want to make? With a built bottom end and a blower, even with stock cams, you can make more than enough power for a street car.
I’m looking to do a moderate build. Shooting for 600, but the internals I’m going with will be capable of a lot more. I understand cams and springs don’t dictate boost. I’m just trying to find out where the ceiling is on stock heads and the components. Like at what power level will the valves start floating
 

07GtS197

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I’m looking to do a moderate build. Shooting for 600, but the internals I’m going with will be capable of a lot more. I understand cams and springs don’t dictate boost. I’m just trying to find out where the ceiling is on stock heads and the components. Like at what power level will the valves start floating
Blak would probably know. I’m not sure what the terminator springs are rated at but seeing that they can handle that power level I’d say anything around that weight spring would suffice. Just don’t go too heavy.

@96blak54
 

Makoto

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I’m looking to do a moderate build. Shooting for 600, but the internals I’m going with will be capable of a lot more. I understand cams and springs don’t dictate boost. I’m just trying to find out where the ceiling is on stock heads and the components. Like at what power level will the valves start floating

your initial question was the first clue, calling 600hp moderate is the second.

as others have said, springs and cams don't care about power. a spring just needs to close a valve, cams open valves at different times, and so you change these things to change that process. its the lung brain for the engine. that's all. only when valves are closed do the rods, pistons, cranks, blocks, head gasket those things take stress when you start cramming boost in. revving higher than factory is where better springs and cams come into play. the more a valve opens in a given timeframe the more it will need help closing so stiffer springs so cams and RPM determine what springs you need.

that said just cams, springs, and head rebuilds will cost you at least 2K on these engines, probably more like 3K once all is said and done. 4 cams are pricey. you're probably approaching 2K just in parts.

you can run stock cams and beefier springs without issue but it would be pointless.

serious question.... have you ever driven a 600hp car that doesn't have all the modern safety nannies?
 
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Pedrothecobra

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your initial question was the first clue, calling 600hp moderate is the second.

as others have said, springs and cams don't care about power. a spring just needs to close a valve, cams open valves at different times, and so you change these things to change that process. its the lung brain for the engine. that's all. only when valves are closed do the rods, pistons, cranks, blocks, head gasket those things take stress when you start cramming boost in. revving higher than factory is where better springs and cams come into play. the more a valve opens in a given timeframe the more it will need help closing so stiffer springs so cams and RPM determine what springs you need.

that said just cams, springs, and head rebuilds will cost you at least 2K on these engines, probably more like 3K once all is said and done. 4 cams are pricey. you're probably approaching 2K just in parts.

you can run stock cams and beefier springs without issue but it would be pointless.

serious question.... have you ever driven a 600hp car that doesn't have all the modern safety nannies?
Yes I have driven high hp cars before. This is my first V8 build and I’m trying to familiarize myself with this modular platform. Appreciate the input, if the car wasn’t a true cobra I’d probably be going a different route with power plant. I know these motors can get pricy when trying to make power
 

Makoto

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Yes I have driven high hp cars before. This is my first V8 build and I’m trying to familiarize myself with this modular platform. Appreciate the input, if the car wasn’t a true cobra I’d probably be going a different route with power plant. I know these motors can get pricy when trying to make power

that wasn't what i asked. have you driven a 600hp car without all the safety nannies before? like, not in a parking lot, i mean in traffic and around town, etc.

i'm only asking this because what you're saying isn't adding up.
 
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Pedrothecobra

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Your question isn’t adding up. What’s a safety nanny? I was asking about stock cams and springs. I guess I can see where my question may have been confusing about what I was trying to find out. I probably shouldn’t have mentioned boost and just asked what the limits of the stock valve train was. I have a habit of typing and sending before clearly thinking about what I’m asking sometimes. Sorry for the confusion I may have caused you
 

Makoto

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Your question isn’t adding up. What’s a safety nanny? I was asking about stock cams and springs. I guess I can see where my question may have been confusing about what I was trying to find out. I probably shouldn’t have mentioned boost and just asked what the limits of the stock valve train was. I have a habit of typing and sending before clearly thinking about what I’m asking sometimes. Sorry for the confusion I may have caused you
your valve train doesn't give a shit about boost. how about that?

safety nanny is traction control, abs, things like that. the tell is the kind of questions you're asking, that says inexperience, which is fine but also why I think 600hp is a PFA number as opposed to a VC number. Feel free to correct me but I've seen nothing to suggest you have any idea what that even means in a mid 90's fox platform car.

My recommendation: have someone else put your engine together and get it back in the car, do full bolt ons, and have it tuned, throw some gears in and have fun.
 

lwarrior1016

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The valve train absolutely cares about boost, when you go to high, you will start getting valve float. OP, I’m not sure what the limit is but I know plenty of guys that have gone to 10-12psi and never had an issue.
 

96blak54

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If the springs were the old style conical shape...pre-95 and not the newer beehive shape, id say their would be a problem, but these beehive springs in the modulars are amazing.
 

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