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Stock Gen 3 bobweight/ complete piston-Rod weight??

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BlueCollarDaily

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Don’t tell me u blew up another engine?
Buddy, you know that cylinder dropped then come back...and it just doesnt sound right...
I had a friend that was gonna let me use his lift Saturday BUT I had forgotten it was my daughters last appointment opportunity for a 4D baby ultrasound.....I really want up under there to check some things like retorque header bolts check trans fluid ect listen to it run on lift ears near number 8....
It did get leaned down due to the tunes scenario of traction control decided to command.....oh I dont know stoich at max boost as a method of traction control!!! WTH....it also short shifted...so the recovery was REAL low but it didnt knock.....but load was thru the ROOF......
I guess with the trans taking like 6-7 seconds to go from reverse to drive, and flaring on 1-2....the engine definitely getting louder on driver side, the case of the disappointing loss of compression on 8, I am just waiting on the other shoe to drop and its HARD to enjoy the car like that.....
I'd like to get my core ready with MINIMUM a forged piston and rings gapped for boost...
I'd like to buy an A10 core and either do both on a straight swap, taking their counter parts and hopefully slowing FOR REAL long term building them....trans first....
I really like having spares. I got spare BBC for the 67 and had Spare LS I sold for money to free up for the Coyote core...i have 2 spare 4l80e for 67 plus one that's in it ect....its just what i do.....

Engine blows I'd be down 3 days...trans blows 1....seems nuts right? Well consider I've paid on a car 13 months that's been running a combined 3months and race season is coming....I missed ALL of last year and I'm not gungho but I'd like to go early while weather is good....



The dude on here with the Edelbrock showed out and he is getting a whipple at half price...I'd like to go run him and see if he should have stuck with it....(friendly like in fact I dont think that or the Edelbrock defection of there Product Manager is public yet or maybe it is, I know they are cutting him a conquest deal but he still wont have a real warranty like EB so I dont understand it on these crap engines hehe)....

I just drove it thru drive thru and its absolutely making noises it wasnt and didnt sound good....
Wish for the best prepare for the worst.....
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Spoke with a friend who has done a gen 3 coyote and he said the most they can be honed is .002", depending on how straight the bores are that maybe enough or it may not, only way to tell is to put a tq plate on it and measure. Usually we bore to .003" before we put the final hone on a block. If a new block is within .005" of final bore we just hone it out in 3 steps, there is a 4th step but its reserved for race only engines that are frequently torn down. Also consider this when doing your rotating assembly, if you are off a few grams here and there with each component, by the time you add then all up you can be out quite a bit and will need to be balanced for sure, just something to think about, we call it a stack up of tolerances.
 

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The rods are about 613-618, pistons are in the low-mid 370s.

But I have to ask, why is the cost of balancing (which is usually around $150-200) the determining factor in this build? Even if you get something "close enough" not to need a re-balance, in the long run it's going to cost you more than if you had balanced them in the first place.
This.

OP, i went down this path and could not find a rotating assembly that was as light as stock. I was trying to avoid balancing also.

I went with Manley H Tuff rods (about 680 grams each--they are individually weighed/matched by Manley before they are sent out). These are about 50-60 grams heavier than the stock rod.

A standard forged piston will be close to he same as stock hyper, but if you go with upgraded wrist pins you will be heavier than stock.

Long story short, you must re-balance. It's not very expensive.
 

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This.

OP, i went down this path and could not find a rotating assembly that was as light as stock. I was trying to avoid balancing also.

I went with Manley H Tuff rods (about 680 grams each--they are individually weighed/matched by Manley before they are sent out). These are about 50-60 grams heavier than the stock rod.

A standard forged piston will be close to he same as stock hyper, but if you go with upgraded wrist pins you will be heavier than stock.

Long story short, you must re-balance. It's not very expensive.

I have a set of rods that are lighter than stock, but they aren't cheap, it depends on the manufacturer. But yes rebalance is needed regardless imo.
 

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I have a set of rods that are lighter than stock, but they aren't cheap, it depends on the manufacturer. But yes rebalance is needed regardless imo.
Sure... i guess it sounded like i was suggesting a lighter/stronger rod does not exist-----i know they certainly do.

But OP is on a budget build so i figured we'd leave those out.
 

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Spoke with a friend who has done a gen 3 coyote and he said the most they can be honed is .002", depending on how straight the bores are that maybe enough or it may not, only way to tell is to put a tq plate on it and measure. Usually we bore to .003" before we put the final hone on a block. If a new block is within .005" of final bore we just hone it out in 3 steps, there is a 4th step but its reserved for race only engines that are frequently torn down. Also consider this when doing your rotating assembly, if you are off a few grams here and there with each component, by the time you add then all up you can be out quite a bit and will need to be balanced for sure, just something to think about, we call it a stack up of tolerances.
Thanks you very much for asking about this for me!!!! Dude even .001 would probably clean up this current block literally...
Yea my former machinist would bore within .004-5 then hone in steps to achieve final spec per hole with him having the pistons in hand...as you alluded to the more race oriented the smoother last step was almost like leather the cylinder would look polished vs cross hatched but that's been a while......I used to be into the minutia....
Would you mind without giving away a trade secret, and you can PM me asking him around the grit he used to hone that plasma bore..looking at it I'd assume fine and slow with plenty of lubricant....
Thanks a lot now that I know it's possible I may just try it....buy 1 piston and floss it back together!!!!
Good point on letting 1 and 2 here add up by the time your done, I have contacted the last guy that did it for me ( retired jet engineer that bought the equipment met him flying RC LOL never know where man)
 
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This.

OP, i went down this path and could not find a rotating assembly that was as light as stock. I was trying to avoid balancing also.

I went with Manley H Tuff rods (about 680 grams each--they are individually weighed/matched by Manley before they are sent out). These are about 50-60 grams heavier than the stock rod.

A standard forged piston will be close to he same as stock hyper, but if you go with upgraded wrist pins you will be heavier than stock.

Long story short, you must re-balance. It's not very expensive.
Thanks Gimmie11s!!!! Ok its fruitless then, did it take Mallory/Heavy metals? Cause that's NUTS expensive around here....did you drop to 11 to 1 wouldn't that absense of dome be lighter? Yes they were trying to spec a narrower and lighter but higher grade pin ( since my power requirement is so low just needing greater than stock cast tuning window or durability...literally one bump and she is gone )....
 
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I have a set of rods that are lighter than stock, but they aren't cheap, it depends on the manufacturer. But yes rebalance is needed regardless imo.
I'm seeing 4.6 rods that are dirt cheap at 602 grams...are they not same length and big and small bore diameters? 4340 for $300?
 
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602 grams do these not fit? There is a new set on Ebay for $300?
Screenshot_20200121-114338_Chrome.jpg
 

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I'm seeing 4.6 rods that are dirt cheap at 602 grams...are they not same length and big and small bore diameters? 4340 for $300?
Mod motor and coyote rods are the same sizes. You can't just compare total weight though. You need to consider where the weight is. Big end vs. pin end, rotating weight vs reciprocating weight.
 

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Mod motor and coyote rods are the same sizes. You can't just compare total weight though. You need to consider where the weight is. Big end vs. pin end, rotating weight vs reciprocating weight.
Ok right I'd by nature of the stock bobweight/counterweights they decided they needed as I've seen before on the pad at the little end....vs having some meat for power near the big end which logically moves said weight closer to crank centerline so less real effect in balance....
So do people run 4.6 rods on coyote or does the entire coyote stack generally not work out because of said variables ( sorry new I know what works with GM)...
 

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Thanks Gimmie11s!!!! Ok its fruitless then, did it take Mallory/Heavy metals? Cause that's NUTS expensive around here....did you drop to 11 to 1 wouldn't that absense of dome be lighter? Yes they were trying to spec a narrower and lighter but higher grade pin ( since my power requirement is so low just needing greater than stock cast tuning window or durability...literally one bump and she is gone )....
I havent balanced yet because my pistons still have not delivered. They are supposed to be here early February (fingers crossed). Local machine shop is highly recommended areound here but i dont know his method of balancing. He quoted me $200.

602 grams do these not fit? There is a new set on Ebay for $300?
Screenshot_20200121-114338_Chrome.jpg
Those would fit and are a good option. Manley's "standard" h beam is close to the same, if not the same rod. They are supposedly rated to ~700 or so HP.

My opinion, id use the stock rod and save $400 over using those, but that's just me.
 
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I havent balanced yet because my pistons still have not delivered. They are supposed to be here early February (fingers crossed). Local machine shop is highly recommended areound here but i dont know his method of balancing. He quoted me $200.



Those would fit and are a good option. Manley's "standard" h beam is close to the same, if not the same rod. They are supposedly rated to ~700 or so HP.

My opinion, id use the stock rod and save $400 over using those, but that's just me.
It really does keep leaning to the stock boss 302 crank and rod and just tossing the mahle no rebalance piston, pin and ring back on...for ultimate budget especially if I can get that tiny scratch honed out....I'm not trying to max effort just get 700wheel to live on 93....
 

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It really does keep leaning to the stock boss 302 crank and rod and just tossing the mahle no rebalance piston, pin and ring back on...for ultimate budget especially if I can get that tiny scratch honed out....I'm not trying to max effort just get 700wheel to live on 93....
That set up would live FOREVER at 700 wheel... probably much more.

that is a STOUT combo.
 
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That set up would live FOREVER at 700 wheel... probably much more.

that is a STOUT combo.
And the entire engine only has 900 miles on it...!!!! Just pop those on, gap a bit for boost, add OPG/S while in there and toss back together....
Because we know the rods hold 900 with e85 and it's my understanding the crank is good for 1200 plus....

I know I cant abuse the piston enough detonation would kill it for sure...BUT the current problem is this blower especially on the 2-3 drops down RPM on recovery at exactly the time it does that this badass efficient blower boost/load spikes for a 1/3rd second...its during those times it rattles ANY at all and the secondary ring breaks....we have actually figured out it likes MORE rpm on top to have a higher recovery ( may swap to a 3.31 to keep recovery rpm up)....when it drops down to like literally in the 4000rpm range on 2-3 ( 3.15s and 28 tire) short shifting that it really tosses load on it especially if its hooked....so ironically its about limiting the amount of cylinder pressure at that low of rpm that's key...hell all the engines would take a single gear to whatever rpm at whatever boost and power....for instance I could do a manual 5th gear pull to 7800 and that was fine...BUT when it drops to recovery rpm at the bottom of 3rd the load/cylinder pressure goes thru the roof and she goes into KR and if you ever hear it....it shows over already not a single time to you get away with it....

I simply need a piston with the strength of the current rotator that will both grow with the plasma bore thermal expansion and be strong enough to endure the conditions that is breaking the stock pistons SECONDARY ring land for 1/3rd a second, then it's fine rest of time....I feel like any increase in the strength of the secondary ring land...and a forged piston matching the growth of the plasma bore is all I need for a fine engine to 7500 and 730 wheel ( is what the build i replicated did on dyno using same tune ) and I asked for less sauce...so 700 wheel...
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