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Crazy Talk
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Fat Kids Rule!
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i will say, throttle response i notice with the crank is a lot more responsive!
 

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Why a crankshaft with more stroke?. Why already have enough torque under 2000 rpms, we need more torque up top. More stroke is not going to solve the issues the 7.3 has.
 

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you want some of this?
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Why a crankshaft with more stroke?. Why already have enough torque under 2000 rpms, we need more torque up top. More stroke is not going to solve the issues the 7.3 has.
Maybe not, but it will add tq all the way across the board, and do it using less cylinder pressure. And given the rpm limit we already have, whats the cons of it?
 

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I know nothing...
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I'm not sure of the over bores of a 444 but .030 over would put about 451, a .015 offset cut on the crank would give you the rest. I'm guessing here as i dont have a calc in front of me but that looks right. cutting .015 off the piston would be easy. I still dont get why the increased quench wouldn't be given the credit for the noticable sotp feel.

Did you dyno the motor Joe?
 

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I know nothing...
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what is "increased quench" ??
Its the flat areas inside the chamber that squeeze fuel and air into the bowl. 1 bene of off-set grinding is the top-cut of the piston. In racing you want the top of the piston to ever so slightly kiss the bottom of the cyl head. That is known as squish, quench, or squinch. The more the surface area of quench the more the directed the combustion. If you are cutting down the top side of the 7.3 piston you're actuly gaining quench area because of the parbolic shape of the piston C-chamber. Just assuming here, but lets say the factory Q of a 7.3 is .035 and we off-set grind the crank .015 and do nothing to the piston you'd still have .020 clearence. The heat in the chamber causes the piston to dome slightly, taking that into acount lets say we grind .0075 from the piston face. We'd have still gained .0075 quench.
 

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im prolly gonna get laughed at here, but here goes. if you put a bigger crank in, that would give you a power increase. so then you would be able to use smaller injectors and turbo to get the same power as our stock crank and bigger injectors. smaller inj's and turbo means less cylinder pressure, i think. there fore stock rods would go farther wouldnt they?? i dont know how much a crank is, but isnt it cheaper than new rods, lets say for the pmr crowd? if your no longer asking the rods to take the abuse. there is alot more to this that i dont know, just askin a question.
 

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3 words for U here, U R clueless ! Not trying to be insulting OK? First off the bigger you make this stuff the heavier it is, a no braniner, that by itself increases stress. Yes more cubes should make more power,burn more fuel, diesel engines are set up as either fuel pinchers, which make little power numbers for the displacement. Do some research and look at the old Cat 3176 series or Cummins whatever the series, they had different fueling, camshaft, turbo, pistons, about everything installed in them. The reasons? Here it is, each engine had design limitations, max rpm, torque curve, all of the specs. given for intended use. Transmission options, differential rations,tire sizes, the list goes on. Let me inform all of you here, the 5.9 Cummins had a factory rated 4,100 rpm rating max to destructive limits. OK, some guys have built these with high dollar parts that have seen 6000 + and survived for a little while on occasion. As far as the 7.3 goes, it is taken about as far as practical with stroke, rod length and piston dimensions. If anyone wanted a longer stroke the crank counterweights would have to be ground for clearance to piston @ BDC, the wrist pin would have to be raised to keep the deck clearance which would weaken the piston ring area. The skirts would have to be shorter making for a less stable piston in the bore. All of these issues make more issues, friction. Unless you make the rod longer, causing even more issues. Now here is another issue with the 7.3. The wrist pin is about half the diameter of a Cummins 5.9/6.7 and less than that in thickness. What do you think about that? I won't even go into the Duramax, that is a joke. OK I will mention that the early Duracraps, not really, I like them too for what they are. Kind of a LS chevy with diesel heads, anyway the had a rep of breaking pistons across in line with the pins, destroying blocks, the crank trigger wheels held on by 3 tiny bolts on the back side of the timing gear, pull the entire front of the engine off and drop the pans, retrieve the bolts and put them back together. When this happens they would leave you stranded and the repair bill was about 2500 just for 3 tiny bolts. Back to the size and power of diesels, everyone knows more power take more fuel, more air, less timing lead, make more boost, reduce compression ratio!!!!!! If you don't do this, you are chancing blown head gaskets, cracked heads, stretched head bolts, broken pistons, pins, bearing/ crank failures, all kinds of stuff. Cat had nightmares with the early 3406 engines, breaking cranks when people demanded shops turn those up because they were de rated. The story is all but endless. The last chapter is like this, fuels have bshp energy ratings, for what ever it. Diesel has about the highest of any of them, meaning it is about the most efficient, meaning the highest level. This is not the highest temperature. That rank belongs to Hydrogen, which has very little btu because it burns so fast, just like Alcohol, we all know that diesel engines make power at low rpm. Gas engines make the their best HP around 6,700 regardless of the size, what to make more power above that range, burn alcohol, forget top fuel, those engine will not live above 6500, everyone thought they spun above that years ago until they started logging data. No matter how you tried to do it, the 7.3 has its limits, and it is not worth going past what the factory did with it ! As far as getting more cubes? .030 is factory recommd. .040 is still doable, now for engines that don't have to live 250k or longer, .060 or even .100 is possible if you fill the lower water jacket with cement. Just be sure the oil cooler ports are left open for water to pass through. There are 7.3's making over 2000 HP out there with pretty much nothing done to bump up the inches. Cummins 5.9l, smaller then 7.3 with 2 fewer bores, making more then the Ford but they can do this because the pins are heavier and the rods are tougher. Few people are worried about bigger inches and less stress no matter which engine they choose, aside from the Duramax, which is 6.6L and they have been pushed up to near the 7.3 region, then you have to deal with aluminum heads which there is nothing you can do to help them here. You want more power and a better engine, start looking at the new 6.7 PS. 1000HP from the factory with some warranty. Technology never goes in reverse !
 

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Project Shamu
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Holy necro batman, you just flamed someone who hasn't logged in since 2015!

Go somewhere else.

Ps. 6.7 PS does not make 1000hp factory, not sure where you came up with that.
 

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forget a stroker, the best money for a BUILT 7.3 are Mahle forged steel pistons and POUR on the boost/nitrous/propane
 
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