I am just learning about engine internals really, i have never dealt with crank specs and/or cam specs ever before so if someone could post a pic of "offset" or maybe a good link that would be :thumb:
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Crower Billet Crankshaft?
- Thread starter SIKDMAX
- Start date
I am just learning about engine internals really, i have never dealt with crank specs and/or cam specs ever before so if someone could post a pic of "offset" or maybe a good link that would be :thumb:
The stroke of the engine is the center point of the main journals (crank centerline) to the center point of the rod journals times two. Because it spins in a circle, you double it.
So if the center of a rod journal is 2" away from the crank centerline, the stroke is 4".
But if you "offset grind" the rod journal, taking all the metal from one side, and none from the other, you can move the stroke larger or smaller, since you've moved the center point of the rod journal. The problem is, for every .1" you want to increase or decrease the stroke, you need to machine off .1" of metal off the journal.
At least in theory, you could take a 7.1 billet crank and offset grind it out to get 7.5 or so.
If you wanted to offset grind a crank, there are many shops that do it, it's a fairly common hotrod mod for those on a budget.
So if the center of a rod journal is 2" away from the crank centerline, the stroke is 4".
But if you "offset grind" the rod journal, taking all the metal from one side, and none from the other, you can move the stroke larger or smaller, since you've moved the center point of the rod journal. The problem is, for every .1" you want to increase or decrease the stroke, you need to machine off .1" of metal off the journal.
At least in theory, you could take a 7.1 billet crank and offset grind it out to get 7.5 or so.
If you wanted to offset grind a crank, there are many shops that do it, it's a fairly common hotrod mod for those on a budget.
Why do we have to add cubes to make power? 403 Ci should be plenty, dodge has only 360Ci and DD making over 1450HP with it!!! Thats 4.03 HP per cube......Not bad for a street diesel.
Did all of us forget how to turbo charge? (Banks)
IMO more cubes means more TQ and more TQ means more broken parts, that great if your sledpullin.......but not drag.
Everything being equal, more CI = more HP.
At any given HP level, a big CI engine has less average cylinder pressure, and can run lower peak cylinder pressure if desired.
If you are making 1450HP with Dodges, then you should stay with it.
Here's what I will say, on a $/HP basis, displacement increases on a Dmax aren't as cost effective as other mods. This is assuming a direct 1:1 increase in power for disp gains.
But nothing but the first 500rwhp is cost effective. Our turbos = $$$, Injectors = $$$, Internals = $$$, etc.
But nothing but the first 500rwhp is cost effective. Our turbos = $$$, Injectors = $$$, Internals = $$$, etc.
And use $12 in ether, $30 worth of fuel additives or nitrous, and $5000 worth of trans parts per pass.
On a naturally aspirated engine sure, but in a boosted application i strongly dissagree
Personally im not making that power with any of my dodges, i know a few folks with 12 and 24 valves that are, one of them has a 6 second rail....
i would like some more enlightenment on why your stamemnet is true , i still think that if your sugesting to feed more air via boost to compensaite for the lack of displacment to make the engine a bigger air pump wich is exactly what it is ( an air pump ) , then under the same pretense the stroker at the same boost levels would still be able to flow more air in turn out powering the stock displacment .
on edit: rpm could be a desciding factor not sure of how high the stroker will rev vs. the stock displacment
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If all things are equall is the opprative word......So that means cylinder head flow as well. If your pushing the engine to the point of restriction, no matter what a stroker kit will not give you any more power in that senario,Acually i think you would have less, due to the increased weight in the recipricating and rotational areas. and the less likly revability of the bigger stoke and the bigger bore coupled with all the extra weight...
But back on topic, i was refering to the Lower cylinder psi that pat claims with a bigger stoke and bore......
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Naw, it's total BS. Sure a 2.4L drag motor can make 1200HP, so you would assume (falsely) that displacement is not that important. But a 9 liter drag motor makes 6000HP+. Both run boost.
It has always boiled down to how much oxygen (and therefore fuel) you can stuff into an engine over a given amount of time. You can increase displacement, boost the air, fortify the oxygen content, increase the RPM. Or you can do all of the above.
It has always boiled down to how much oxygen (and therefore fuel) you can stuff into an engine over a given amount of time. You can increase displacement, boost the air, fortify the oxygen content, increase the RPM. Or you can do all of the above.
If all things are equall is the opprative word......So that means cylinder head flow as well. If your pushing the engine to the point of restriction, no matter what a stroker kit will not give you any more power in that senario,Acually i think you would have less, due to the increased weight in the recipricating and rotational areas. and the less likly revability of the bigger stoke and the bigger bore coupled with all the extra weight...
But back on topic, i was refering to the Lower cylinder psi that pat claims with a bigger stoke and bore......
have they done any flow test to see if the engine/displacment can flow more air then some off the ported dmax heads can except, asuming you have a cam with the proper grind .
...
But back on topic, i was refering to the Lower cylinder psi that pat claims with a bigger stoke and bore......
Yup. Do the math.
OK, bigger bore and longer stroke mean that you can get more air into a bigger area and for a longer period of time, giving you more overall air to compress, since there is more air to compress, there has to be more pressure, (since pressure is the driving force of the internal combustion engine!)
Can you show me that math on how more CI makes for lower cylinder psi ?
That just dosent jive with normal physics.