max psi on cobra
12-02-2005, 03:22 AM
#1
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max psi on cobra
sup guys...im gettin a vortech s/c for my 97 cobra....got basically a stock motor that has been rebuilt and has around 20K miles on it...for the guys who have a Vortech S/C...what would be the max boost i could run and not harm my motor...im gettin the whole works...S/C..aftercooler..fuel pump..and gettin it tuned...thanx for the help
12-02-2005, 04:39 AM
#2
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RE: max psi on cobra
If it was NOT built with stronger internals then that rebuild doesn't matter in this case. 8psi most boost with a stock 4.6L. A few people have said 9, maybe 10..but I wouldn't push it. Personally i'd stick with 8. Depending on the s/c, (decent one) even at 8psi you're lookin at atleast a 30% hp increase..which is 91.5hp more, putting you at 396hp. Then with a tune you're lookin at another 7-15hp (I think). 403-411hp. That's more than 03-04 cobras. 
12-02-2005, 09:02 AM
#3
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RE: max psi on cobra
ORIGINAL: Stang9946
If it was NOT built with stronger internals then that rebuild doesn't matter in this case. 8psi most boost with a stock 4.6L. A few people have said 9, maybe 10..but I wouldn't push it. Personally i'd stick with 8. Depending on the s/c, (decent one) even at 8psi you're lookin at atleast a 30% hp increase..which is 91.5hp more, putting you at 396hp. Then with a tune you're lookin at another 7-15hp (I think). 403-411hp. That's more than 03-04 cobras.
If it was NOT built with stronger internals then that rebuild doesn't matter in this case. 8psi most boost with a stock 4.6L. A few people have said 9, maybe 10..but I wouldn't push it. Personally i'd stick with 8. Depending on the s/c, (decent one) even at 8psi you're lookin at atleast a 30% hp increase..which is 91.5hp more, putting you at 396hp. Then with a tune you're lookin at another 7-15hp (I think). 403-411hp. That's more than 03-04 cobras.
i'm running 10psi on my vortech for my GT.
12-03-2005, 01:29 PM
#4
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RE: max psi on cobra
well...vortech said w/ my car...the s/c kit and the aftercooler...would make my motor push out 484 hp out of the motor...but also it says..when u get the aftercooler...it comes w/ a different pulley..is that because u can run more boost w/ the aftercooler?...on one page it said 96-98 cobra S/C w/ cooler...9-11psi?..can someone help me out..thanx
12-03-2005, 03:03 PM
#5
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RE: max psi on cobra
im pretty sure thats because before the 99 cobras they did not ave forged internals come stock, which mean too much psi and ur motor is guna blow, so 9-11 is the safest amount of psi for your car stock, if you get it with forged internals you can practically go to the highest amount of psi available
12-03-2005, 03:47 PM
#7
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RE: max psi on cobra
yea about the forged pistons...a guy at UPR had nitrous in his 96 cobra and he explained to me that it was ok to put nitrous on a stock cobra like my year because..yes they didnt come w/ forged piston..but the pistons arent like stock pistons...they are just a little weaker that forged so they would hold nitrous like a forged piston would
also..im gettin a aftercooler..so im gonna lose about 3 psi..soo i need to push around 12-13psi to compensate for the loss
also..im gettin a aftercooler..so im gonna lose about 3 psi..soo i need to push around 12-13psi to compensate for the loss
12-03-2005, 08:25 PM
#10
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RE: max psi on cobra
Your Cobra has a steel crank, powder cracked rods and hypereutetic pictons. The aftercooler is gonna cause a loss of boost, therefore the blower can be spun at 12 psi and the engine internals will only see about 8-9 lbs of boost after the loss of boost from the aftercooler. Hypereutetic pistons are good till they see detonation and then they crack or melt. They arent a guaranteed bet for any type of power adders, but they will hold up for quite some time if tuned correctly. The rods are what you really need to worry about. If by chance you see more boost than the enging can take (anything over 10 lbs) then they will bend like a bannana and come out the side of the block. It isnt a pretty sight and definetly not cheap to fix.