blkZooM
10-04-2013, 04:31 PM
Well lets some good tech conversation going, I've had a question I have been asking myself the last couple of days and I wanted to know if someone with the knowledge could help me out here.
Trying to pick a compression ratio to go with when building a shortblock, the goal is to between 9.4.1 and 9.8.1. and I am going with the 3.750 crankshaft which, bored over .30. I'll be going ported heads route, I have the very annoying head tick and want the 05 revised heads and most likely custom grind cams from NA SVT.. Now with all the mods above plus long tube would drop boost from the research I've done about 4-5 psi because of how efficient the motor now is.
The question I need help with is this, lets say I have a Whipple with a Upper and lower combo of stock lower and 3.2 upper which gives us 17 psi but with the new motor i am only seeing 12-13 psi. in reality (I think I could be wrong here) the blower is still flowing in 17 psi worth of air.
The 03-04 cobras guys state 18 psi is the max you should be running on 93 pump gas and they have 8.5.1 c/r. So i ask, say my max psi with my combo should be 17 ( I know it would be a lot lower) psi on 93 pump gas but I am only seeing the 12-13 I stated earlier would I still have to treat it as if I am at the max psi that my combo allows or am I able to just pulley down to get back up to the 17 psi. To get back to the 17 psi I think you have to run a 2.8 upper which is flowing in 21 psi of air which we know is too much for pump 93.
Just something to get us talking on here thanks for the help in advance for the help
Trying to pick a compression ratio to go with when building a shortblock, the goal is to between 9.4.1 and 9.8.1. and I am going with the 3.750 crankshaft which, bored over .30. I'll be going ported heads route, I have the very annoying head tick and want the 05 revised heads and most likely custom grind cams from NA SVT.. Now with all the mods above plus long tube would drop boost from the research I've done about 4-5 psi because of how efficient the motor now is.
The question I need help with is this, lets say I have a Whipple with a Upper and lower combo of stock lower and 3.2 upper which gives us 17 psi but with the new motor i am only seeing 12-13 psi. in reality (I think I could be wrong here) the blower is still flowing in 17 psi worth of air.
The 03-04 cobras guys state 18 psi is the max you should be running on 93 pump gas and they have 8.5.1 c/r. So i ask, say my max psi with my combo should be 17 ( I know it would be a lot lower) psi on 93 pump gas but I am only seeing the 12-13 I stated earlier would I still have to treat it as if I am at the max psi that my combo allows or am I able to just pulley down to get back up to the 17 psi. To get back to the 17 psi I think you have to run a 2.8 upper which is flowing in 21 psi of air which we know is too much for pump 93.
Just something to get us talking on here thanks for the help in advance for the help