
How much boost can a stock zetec bottom end handle
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I am running a 9 psi supercharger and am wondering how much boost it can take and if there is a HP limit for the stock bottom end. 

Graphite ZX3 VFstage 2 Supercharger intercooled, Crower stage 2 forced ind cams, Crower Valve Springs, 9:1 pistons, Fidanza timing gears, Eagle Rods, Extensive Head porting and machined, 9:1 pistons, Fidanza timing gears, Eagle Rods ect..
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I've hear 12psi is about it, but i have read some shop running more. (C-F-M?) 9psi is safe on it, but more, eh, i'd be leery.
Slower than your stock focus.
How much boost your bottom end isn't going to rely on just the boost level, the PSI is more or less a rating of resistance.
If you have a good tune, you're intercooled, runs a touch rich, you could prob go a lot more boost.
No intercooler, AFR is perfect/touch lean, not much more boost. Excess fuel helps cool down the combustion chambers, thats why some plugs and exhaust ports on boosted motors are sooty, from the excess fuel.
Remember, the bottom end has powered metal rods, they do bend when stressed enough.
If you have a good tune, you're intercooled, runs a touch rich, you could prob go a lot more boost.
No intercooler, AFR is perfect/touch lean, not much more boost. Excess fuel helps cool down the combustion chambers, thats why some plugs and exhaust ports on boosted motors are sooty, from the excess fuel.
Remember, the bottom end has powered metal rods, they do bend when stressed enough.
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It is 100% up to the tune. There are people running 375 hp on stock internals, but then there are people running 190 and blow up.
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Hector @ CFM is running 16lbs with a vortech running a standalone. He hit 12.9 and clocked in at just under 300whp with a ported head. he has a last name too but I can't pronounce it.
reconstruction.
trahma wrote: Hector @ CFM is running 16lbs with a vortech running a standalone. He hit 12.9 and clocked in at just under 300whp with a ported head. he has a last name too but I can't type it.
Fixed.
I have heard about that vortech powered car, I was really looking forward to putting a vortech on mine next spring with the ported head

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well .......sc0tty8 wrote:trahma wrote:Hector @ CFM is running 16lbs with a vortech running a standalone. He hit 12.9 and clocked in at just under 300whp with a ported head. he has a last name too but I can't type it.
Fixed.
I have heard about that vortech powered car, I was really looking forward to putting a vortech on mine next spring with the ported head


focinite wrote:well .......sc0tty8 wrote:trahma wrote:Hector @ CFM is running 16lbs with a vortech running a standalone. He hit 12.9 and clocked in at just under 300whp with a ported head. he has a last name too but I can't type it.
Fixed.
I have heard about that vortech powered car, I was really looking forward to putting a vortech on mine next spring with the ported head
No more focus for me. That chapter is closed and its time to move on, no more fords but whats in the driveway. I already am on chapter 7 of the tbird book. 1 chapter is enough for me on the focus.