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ford ranger
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Discussion Starter #1
does anyone know what a stock rod weighs?

i want to build a nasty NA motor but am not sure even a shot-peened/cryo'd stock rod is gonna be enough. im just worried that h beams are going to add to much weight to the bottom end.
 

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68 Camaro
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you wont come near 220 hp. your safe with stock rods. they will be your lightest bet
 

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I too was just wondering stock rod and stock piston weights and if anyone had given consideration to crank counterweights with standard vitara builds.

-Luke
 

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ford ranger
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Discussion Starter #7
you wont come near 220 hp. your safe with stock rods. they will be your lightest bet
this isnt your average toy high C/R d build. we're going big here, 12:5:1 fully ported, intake mani, full tuned exhuast, light everything, and a big shot of nO2. im seriously looking and planning for more than 300hp. im into doing shit ppl say cant be done, lol i helped build a 855 c.i. cummins that makes 1500+ hp, stock it made 400. everyone said it could never be done, its in a semi truck used in tractor pulling.
 

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68 Camaro
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wtf a huge shot of nitrous is not NA. thats forced induction... and if your gonna have "300 hp" on your nitrous build (most people get this idea then abandon it when they realize how superior turbocharging is). why you worried about some grams on your connecting rods.



and please dont try and show off a big dyno dick with other stuff youve built. it annoys the piss out of me...rant over


also no one is saying that cant be done. a 200 shot of nitrous on a small displacement import just isnt that efficient.
 

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spray isnt NA

who gives a shit about diesel

you're mixed up anyways. you probably turned 400TQ into 1500

thats easy with a diesel.
 

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I too was just wondering stock rod and stock piston weights and if anyone had given consideration to crank counterweights with standard vitara builds.

-Luke
I had the same questions when I started to build my motor. Changing the rod and piston mass will not directly affect crankshaft balance because the cranks are neutral balanced with no rotating mass. The flywheel is neutral balanced and the harmonic balancer is neutrally balanced. The reason the crank is neutral balanced is because with an inline 4 there is always cylinders 1 and 4 going up/down, and 2 and 3 going up/down 180 degrees apart. As long as the weight of the connecting rod, piston, wrist pin and clips are equal in all 4 cylinders the engine will be balanced.
 

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the only time you need to worry about rod weight is during very high rpms where rod stretching and rod bolt stretching are a problem.

shotpeened and magnafluxxed OEM rods will suffice, and ARP bolts

hell, Im selling a set of d15 rods that have this treatment.

Your local performance or machine shop can answer any questions you have
 

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spray isnt NA

who gives a shit about diesel

you're mixed up anyways. you probably turned 400TQ into 1500

thats easy with a diesel.
negative the engine he is talking about is a cummins ntc 400 big cam and it has 400hp stock and when built right can put well over 1500hp to the ground.
i make my living building diesel engines.

but any how stock rods with every mod possible are not gonna hold a shot of n2o big enough to make 300hp
 

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if it was stock 400hp and turned to 1500

motherfucker has enough torque to rip a city block in half! :3dbiggrin:
 

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12.5:1 c/r really isnt big time... theres dd d16 with 12:1 c/r running on 87 oct.

and as many said stock rods and nitrous to make a 300hp d is not gonna happen. but you sure can try lol.
 

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A set of FJ rods or China H beams might not cost any more than stock rods by the time you grind off forging flash, cut and shut the big ends, fit ARP bolts and shot peen them
 

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I had the same questions when I started to build my motor. Changing the rod and piston mass will not directly affect crankshaft balance because the cranks are neutral balanced with no rotating mass. The flywheel is neutral balanced and the harmonic balancer is neutrally balanced. The reason the crank is neutral balanced is because with an inline 4 there is always cylinders 1 and 4 going up/down, and 2 and 3 going up/down 180 degrees apart. As long as the weight of the connecting rod, piston, wrist pin and clips are equal in all 4 cylinders the engine will be balanced.
Ah yes that makes sense! I guess it was a two parter; isn't the weight of an individual counter weight on the crank designed for the original weight of the factory piston/rod/wrist pin/rings?

Thanks!

-Luke
 

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ford ranger
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Discussion Starter #20 (Edited)
negative the engine he is talking about is a cummins ntc 400 big cam and it has 400hp stock and when built right can put well over 1500hp to the ground.
i make my living building diesel engines.

but any how stock rods with every mod possible are not gonna hold a shot of n2o big enough to make 300hp
correcto! you happen to work for Pittsburgh power or PDI?

i never intended to run a huge shot of no2 on stock rods, and i never planned for more than a 100 shot. i started the thread to see what kind of wieght the stocker run. i'll prolly just use a set of H or beefy I beams in the build if i ever get around to it. overkill is better than a aerated block.
 
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