V6 tC
i still say that compression ration is WAY high if you're looking to put out more boost... i think you have it backwards... maybe years ago you wanted higher compression... nowadays high compression is for NA builds, not forced induction...
higher compression ration = higher octane... can you readily get 100 octane? can you afford it daily? i'm guessing that's not an issue because it looks like you have plenty of money to drop into the car.
but, there's a reason why almost every single factory built f/i car's compression ration is in the 9.5:1 or lower range... because going much higher than that on a boosted car is stupid.
higher compression ration = higher octane... can you readily get 100 octane? can you afford it daily? i'm guessing that's not an issue because it looks like you have plenty of money to drop into the car.
but, there's a reason why almost every single factory built f/i car's compression ration is in the 9.5:1 or lower range... because going much higher than that on a boosted car is stupid.
Originally Posted by D4u2s0t
i still say that compression ration is WAY high if you're looking to put out more boost... i think you have it backwards... maybe years ago you wanted higher compression... nowadays high compression is for NA builds, not forced induction...
higher compression ration = higher octane... can you readily get 100 octane? can you afford it daily? i'm guessing that's not an issue because it looks like you have plenty of money to drop into the car.
but, there's a reason why almost every single factory built f/i car's compression ration is in the 9.5:1 or lower range... because going much higher than that on a boosted car is stupid.
higher compression ration = higher octane... can you readily get 100 octane? can you afford it daily? i'm guessing that's not an issue because it looks like you have plenty of money to drop into the car.
but, there's a reason why almost every single factory built f/i car's compression ration is in the 9.5:1 or lower range... because going much higher than that on a boosted car is stupid.
Let's address the octane rating I'll need for the car. I'm smelling premium daily and 100 on race day. I can run premium always in it, and guess what.. I'd run C16 in it if I had to daily.
Now on to the compression.. You seem to have a point about NA race cars run under high compression and factory boosted cars have lower compression.. but have you thought about why either of these are true? Come up with some reasons rather then generalizations so we can actually talk about something here.
Here's some thoughts I had.. When people drop the compression their looking to boost 20ish psi.. now our target is 10 by the end of the summer. huge difference. Compression helps determine the amount of power you get out of the mods on your car. Running boost under high compression breaks ____. We are aware of this and don't care too much. OMGWTFDOOD. Well.. We figure to get the best out of the swap we're gonna have to at least blow one engine.
Why do NA people run high compression?!? well.. Hrm. That's simple.. upping the compression produces power.
sorry, and you're right... but you're comparing apples to oranges here... N/A and F/I builds are 2 totally different, and opposite things. so you can't say "If it works for N/A builds it must be good for F/I builds too. for the compression ratio that you're looking at, you probably shouldn't go over about 6 or 7psi. anymore and you're asking for trouble because you will most likely blow your engine.
let me explain it like this. when you are under boost, your compression ration is higher than when you're not under boost. so starting with a lower compression ration, say 7:1 or 8:1 and you're running 10 or 12 psi, under boost your actual compression ration (there's too many variables to give exact #'s here) will be much higher. which means much more wear on the engine. if you're running 10.75:1 ratio, with 10 pounds of boost, you can instead run a 9:1 ration, 15 pounds of boost, make the same power, (or more) and have a more reliable engine.
let me explain it like this. when you are under boost, your compression ration is higher than when you're not under boost. so starting with a lower compression ration, say 7:1 or 8:1 and you're running 10 or 12 psi, under boost your actual compression ration (there's too many variables to give exact #'s here) will be much higher. which means much more wear on the engine. if you're running 10.75:1 ratio, with 10 pounds of boost, you can instead run a 9:1 ration, 15 pounds of boost, make the same power, (or more) and have a more reliable engine.
so if anyone doesn't understand, to sum it up think of it like this. You can cook dinner on a stove, or you can cook dinner on the grill. if you're making burgers and hot dogs, the grill is pretty kick ___. but, if you're trying to make spaghetti and meatballs you wouldn't want to use the grill.
same principle.
if that doesn't make sense it's because i've been staring at the editing computer all day and i'm fried...
same principle.
if that doesn't make sense it's because i've been staring at the editing computer all day and i'm fried...
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Strictly Scionized
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Joined: Oct 2004
Posts: 1,284
From: White Marsh, Balti Co., MD
hey turbo diesel engines run high compression and 60psi of boost you dont see them breaking.....
anyways well if the guy wants to run high compression and low boost then be it, who are you to tell him what to do with his money.
on top of that its all in the build, you can have a low compression engine and blow due to high boost, and vise versa.
props on the V6 swap though...
anyways well if the guy wants to run high compression and low boost then be it, who are you to tell him what to do with his money.
on top of that its all in the build, you can have a low compression engine and blow due to high boost, and vise versa.
props on the V6 swap though...




