Highest compression for boost?
- Thread starter trxcobra
- Start date
Nope
I can't agree more. When adding more components to a system you increase the chance of a failure. I put BAPs, BASs and Meth in the same category, if they are required you need to rethink the combo and improve/fix what they "band-aid-ing."
I’ll let you in on a pet peeve of my own.
When discussing or communicating a topic of importance to others, someone drags grammar into the conversation putting it “front & center” of the discussion. You do that in my line of business will get you into the boss’s office in a hurry. It’s “petty” and distracts from the conversation.
Better them "than" me.
On a serious note, take a look at the compression calculator I posted.
That's a neat app but it doesn't take into account flow restriction in the intake and exhaust system. Boost is just a measurement of those flow restrictions. Bigger valves, ported heads, cam specs and exhaust flow all that an impact how much volume of charge actually makes it into the combustion chamber. An engine with high volumetric efficiency will register low boost and vice versa.
:burnout:
:burnout:
Sorry, but I lol'd to this.
Had to do this. "You're" lol:shrug:
10.7:1 compression, 2.3L Whipple, and pump gas...going on three years.
Static compression is only part of the story. Quench, intake temps, coolant temps, coatings, valve material, cam selection, cam centerlines, etc. 195-200psi cranking compression here. We've run pump and boost on engines with higher cranking as well. And there are plenty of Coyote engines running around with 11:1 and boost.
The ignition tuning isn't difficult it just requires attention and lower numbers. Lower ignition values that make the same or more power is an advantage is its own right. Easier for the pistons to round TDC.
This debate will never end it seems. The people running less compression will never make the power or fuel economy as those running more.
Static compression is only part of the story. Quench, intake temps, coolant temps, coatings, valve material, cam selection, cam centerlines, etc. 195-200psi cranking compression here. We've run pump and boost on engines with higher cranking as well. And there are plenty of Coyote engines running around with 11:1 and boost.
The ignition tuning isn't difficult it just requires attention and lower numbers. Lower ignition values that make the same or more power is an advantage is its own right. Easier for the pistons to round TDC.
This debate will never end it seems. The people running less compression will never make the power or fuel economy as those running more.
Following the trend it should be you're not your. :dw: :lol1:
Edit... looks like I was beat to it :lol1:
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I'm starting to wonder if he did it on purpose.
Regardless, great thread. Love reading anything with these guys talking in them, very informative.
Your engine and the new 5.0 you talked about "get away" with the compression they have because of massive cam overlap thus lowering the dynamic compression. Someone using stock cams can't run nearly that amount of compression.
Steve, they won't listen.
Oh, we'll listen. There's just one problem: Boost is cheap to add, compression is expensive to remove.
Nobody wants to build a second motor cuz the first didn't meet their power goal.
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You've made my point.
I think there is a lot of thought that needs to be worked out when designing an engine for boost. Each power adder with different characteristics is going have a different affect on an engine's behavior with the octane, and boost level in the rpm range you want. I think that static compression ratio should not be looked at as heavily as dynamic compression.
Here is a link that will probably cause more questions than answers but it will give you an idea of what I'm talking about: http://speedtalk.com/forum/viewtopic.php?f=1&t=6094&sid=011fa2235d06a2bca2bb131b4bbf50c4&start=15
Here is a link that will probably cause more questions than answers but it will give you an idea of what I'm talking about: http://speedtalk.com/forum/viewtopic.php?f=1&t=6094&sid=011fa2235d06a2bca2bb131b4bbf50c4&start=15
I am running flat top pistons (told this was 10.5:1 by Manley) and a Procharger P1SC. Highest boost during tuning was 12psi (I have an overdrive crank pulley). Tuner recommended an octane booster (torco) which gets added during every fill up to avoid detonation. Torco adds +11 to the octane rating. Forged lower end. Teksid block. 505 whp @ 5700rpms on a conservative tune.
Not sure if you can run this combo on straight pump gas. I was told by the tuner that the flat top pistons were limiting me.
Not sure if you can run this combo on straight pump gas. I was told by the tuner that the flat top pistons were limiting me.
505 hp with a procharger is pretty mild. A Terminator motor with dished pistons will be closer to 700 running that combo. Kinda like what your tuner was telling you.
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505 hp with a procharger is pretty mild. A Terminator motor with dished pistons will be closer to 700 running that combo. Kinda like what your tuner was telling you.
An 03/04 engine with 12psi will make at least 50rw less than a flat top pistoned engine. I know as I've had experience with both.
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