How can i get my compresion ratio?
06-03-2010, 09:01 AM
#3
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Join Date: Mar 2010
Location: georgia
Posts: 52
306 ported polished and shaved heads f303 cam 1.6 rr. the bottom end has been built to just dont know the specs on it. i know the have comprestion testers but can u somehow get your ratio from one of those?
06-03-2010, 09:19 AM
#4
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Join Date: Jun 2010
Location: Iowa
Posts: 269
you dont. you get compression ratio using the calculations on deck height, piston cc, head cc, gasket thickness blah blah blah blah blah. we need to know the measurement of those things to calculate compression ratio.
what cc chamber are your heads? cc of your pistons or are they stock pistons on the 87? thickness of your head gasket. i doubt you are exceeding 10:1. you're probably 9.3-9.5:1 compression ration
what cc chamber are your heads? cc of your pistons or are they stock pistons on the 87? thickness of your head gasket. i doubt you are exceeding 10:1. you're probably 9.3-9.5:1 compression ration
06-03-2010, 11:13 AM
#5
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Location: georgia
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yea i dont know most of that right off hand. a couple of my mustang friend around town was just tryin to figure out why the car pulls like it does. iv have riden in boosted cars and nitrous cars that dont pull as hard as mine and mine is n/a. ill see if i cant round that info up tho so we can get an idea of what it is.
06-03-2010, 11:28 AM
#6
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Location: alabama
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Well could be your parts are working together! simple as that! gearing tires etc....
piston cc`s (dome reliefs dish flat)
head gasket thickness
total volume of the cylinder
piston to deck clearance
combustion chamber cc`s
cc`s must be converted to cu in!
plus the formula will give you the compression ratio!
unless you have a closed chamber head or dome pistons you wont be over 10 :1 like posted above. most you can get with a stock 4 relief flattop is about 9.6 or 9.7 : 1 unless you have the small chamber afr heads or bigger bore/stroke!
piston cc`s (dome reliefs dish flat)
head gasket thickness
total volume of the cylinder
piston to deck clearance
combustion chamber cc`s
cc`s must be converted to cu in!
plus the formula will give you the compression ratio!
unless you have a closed chamber head or dome pistons you wont be over 10 :1 like posted above. most you can get with a stock 4 relief flattop is about 9.6 or 9.7 : 1 unless you have the small chamber afr heads or bigger bore/stroke!
06-03-2010, 11:31 AM
#7
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Join Date: Jun 2010
Location: Iowa
Posts: 269
whats the rest of your car build consist of? i doubt its as fast you think...not being a dick, just being realistic. a motor with those parts would hardly break 240rwhp.
possibly just hookin hard and it feels faster. best bet is take her to the track and get some real results.
possibly just hookin hard and it feels faster. best bet is take her to the track and get some real results.
06-03-2010, 11:37 AM
#8
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Join Date: Jul 2008
Location: alabama
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It`ll bog prolly! traction is a bad thing to low powered cars! spinning isnt winning lol! and a good tire could make you sick! a little slipping of the tires to get the rpms going wont hurt but smokey launchs suck!
a 306 with those parts would be ok against other stockish mustangs and camaros lol!
and the compression tester is only to test cylinder pressures related to one another!
i dont think you can convert kpa to actual compression, i could be wrong though!
i have seen a tester show 95 on each cylinder and it was a 12:1 engine, and i seen a 9.5 : 1 make 115 per cylinder so i do believe it wont matter what your tester says just that the compression is equal among your engine!
a 306 with those parts would be ok against other stockish mustangs and camaros lol!
and the compression tester is only to test cylinder pressures related to one another!
i dont think you can convert kpa to actual compression, i could be wrong though!
i have seen a tester show 95 on each cylinder and it was a 12:1 engine, and i seen a 9.5 : 1 make 115 per cylinder so i do believe it wont matter what your tester says just that the compression is equal among your engine!
Last edited by Venomantidote95; 06-03-2010 at 11:41 AM.
06-03-2010, 11:44 AM
#9
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i hear ya im gonna take it to the trake when i get some drag radials. it dont do anything but spin if i get on it all the way threw third so i know it wont hook at the track. but i didnt know if there was some way to convert that reading the tester gives u to the ratio or not but u guys ansered that question. i will try to dig up all the specs and post em later on tonight. thanks for the imput so fare,
06-03-2010, 11:54 AM
#10
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and i know spining doesnt mak it fast but i said it pulls hard not it spins hard. if i ease into it and keep it from spinin is when it puls so hard. thats what me and my friends was trying to figure out. thers s pretty good bit of stuff done to the car. but when u ride in it it dont seem like thers enough stuff done to it to be that quick. now dont get me wrong im not bragin i have had 4 5.0 i know what they do stock and with a little mods. and i know this ones not the fasest on the road and im not sayin its a 11 second car. but ifs really fast for what it has done to it. thats why i was tryin to figure out the comprestion ratio.