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My Build is going well but I need clarification on these pistons and rods.
Does the side of the piston with the deepest depression for the valves align with the intake? The Intake Valves are larger.
Does it matter which way Carillo rods mount? The only markings are stamping on the big end. Do those markings point to any particular side?
 

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Richard Jemison
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The Large valve relied is the intake one.
The Rods are positioned so the offset`s side matches the directions in the manual.
#1 the offset is to the front of the engine
#2 i`s to the rear
#3 it`s to the front
#4 to the rear
 

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Discussion Starter #3
The Large valve relied is the intake one.
The Rods are positioned so the offset`s side matches the directions in the manual.
#1 the offset is to the front of the engine
#2 i`s to the rear
#3 it`s to the front
#4 to the rear
1664265

like this?
 

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what engine are you building and who supplied your pistons and rods. The Carrillo Bullet is a relatively new add to their line. Any one have a review of them.

Ciao

Ken
 

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There is a picture in the manual of how the offset on each rod goes. Once you have them in, you can check they're right by looking up from underneath. Each rod's top end should be roughly centered in the pin boss. If noticeably to one side you have it in backwards. Stock rods have numbers on them, all face the same way, but aftermarket rods probably not the case.
Andrew
 

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Discussion Starter #6
There is a picture in the manual of how the offset on each rod goes. Once you have them in, you can check they're right by looking up from underneath. Each rod's top end should be roughly centered in the pin boss. If noticeably to one side you have it in backwards. Stock rods have numbers on them, all face the same way, but aftermarket rods probably not the case.
Andrew
Thx, as I installed them I verified that the alignment is perfect! The area on the rods that protrudes faces the small mains.
 

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Hi Gzucca,

I have at home the exact same pistons (JE) and rods (Carillo) .... I make an educated guess and dare to say that you bouhght your rebuild kit at Spruell (no advertising meant here)?

The engine kit for mine are for a 1300, as I initially wanted to build up a hi revy engine, but my plans changed a bit.

What I really wanted to know is if the crankshaft needed to be lightened the same amount as the difference noted between the weight of the initial rods&pistons or if its viable to go with the carillo&JE pistons on the original (not Lightened) crankshaft.

Thanks for your suggestions and all the best for 2021

Thomas (Toli0815)
 

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Carello rods and JE pistons set up in a 1600 race engine.

1666105
 

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Race builders may chime in but I believe the crank is fine as is. Balanced unto itself and the lighter the load from pistons and rods, the better.
Andrew
 

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Discussion Starter #10
Hi Gzucca,

I have at home the exact same pistons (JE) and rods (Carillo) .... I make an educated guess and dare to say that you bouhght your rebuild kit at Spruell (no advertising meant here)?

The engine kit for mine are for a 1300, as I initially wanted to build up a hi revy engine, but my plans changed a bit.

What I really wanted to know is if the crankshaft needed to be lightened the same amount as the difference noted between the weight of the initial rods&pistons or if its viable to go with the carillo&JE pistons on the original (not Lightened) crankshaft.

Thanks for your suggestions and all the best for 2021

Thomas (Toli0815)
I did not lighten the crank, I didn’t see a need in that. The piston rod combo are a 1/2 lb lighter per cylinder. 2lbs total, that is awesome!!! I may buy titanium valve retainers, there about $300 and the idea seems really cool!
 

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The less you stress the crank and rod bolts the better. Stock rods are strong but heavy. Stock pistons are heavy.
Andrew
 

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Thanks Gzucca & Andrew for your reverts.

Well then... I believe it’s safe to say that I will leave my crank how it is and just have it balanced with the flywheel fitted. I’ll build up my engine with my new JE pistons and my Carillo rods just matched for weight.

Thomas
 

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It is better to balance them separately in case you need to replace the flywheel in the future.
 

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Andylarry... now you have me puzzled 🤨....

I was always of the meaning that crankshaft and flywheel need to be balanced out together (as one unit if you prefer) as only then the unit can be trued to attain the smallest possible measurable unbalanced mass... but I’m happy to learn if wrong 😉

Thomas
 

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@Toli0815, My understanding is that, ultimately you are correct. Doing it your way, AND adding the front crankshaft pulley and pressure plate and all their fasteners is the most accurate way to do it. But then you are stuck having to pull it all apart and rebalance the entire assembly if one component needs to be replaced. If each part is balanced separately then each part can be replaced without a full teardown.
 
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Hi Andylarry,

I understand now your logics... (Fiat Lux ... as the old romans would say 😉), and yes you're right stanting that crankshaft pulley MUST also be part of the unit to be balanced (Meaning: Crankshaft pulley + Crankshaft + Flywheel.... put together as ONE unit and balanced)...

This said your idea is clever and is to be thought about 🧐... If i understand you correctly your method suggests to: balance each part by its own (Pulley by its own, crankshaft by its own and finally flywheel by its own...) and that once all parts are balanced... put everything back together and rebalance everything?.... sounds sweet and expensive...

Thomas
 

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No need to rebalance the entire assembly if each part is individually balanced. Of course, if you are building a top level competition grade engine that will be constantly run within 1 RPM of flying apart, AND, will be rebuilt (and rebalanced) after each race, then sure, balancing the entire group of components together is best. For most anything less than that, simply having each part balanced separately is just fine.
 

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Much also depends on if you are building just one, that you will never need to replace, or several with matched components for race. For example, will you replace the clutch at any time? Better it's balanced to itself. Any chance the crank pulley will get broken? Balance it to itself. Flywheel? Rods? Pistons? Ever need partial component replacement?
With a performance engine build, you pretty much understand component service life. Balance items to themselves that might reasonably need future replacement.
 

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What ever you do you need to make sure your balancing shop is on the same page as you. Because it will do no good if you balance up the individual parts then they use the flywheel and or the front pulley for weight adjustment to balance the assembly.
I have a front pulley with a huge weld on it that surely was not needed to balance it alone and another pulley or the same one with weight ground off a groove lip.

That weld if on a cast iron pulley was not a wise idea in and of itself as there are probably some cracks there some where.

ken
 

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Richard Jemison
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I agree with Gordon. balancing everything together isn`t the way to do it on a 4 cyl inline engine. balance all the components separately. Flywheel/rods/pistons and front pulley if you must. (To small to waste $$ doing)
 
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