Xu10J4Rs Gt3582R Steel Crank

[dimmadave 0]

Hi people am in progress of building a 16v turbo i have forge gti6 pistons i was wondering on my options on a steel crank and rods combo

[Sandy 189]

Turbo diesel XU9 crank is forged steel, 88mm stroke and very strong. Aftermarket options are limited and sometimes questionable quality.

[dimmadave 0]

I no of the 88mm crank xud/mi16 but unsure of wat forged rods to buy as i dont want to increase the cr .

[welshpug 1,622]

whatever suits your piston crown height/crank stroke/block deck height.

[dimmadave 0]

I am Fabricating a 316l side mount equal length manifold the moment n not stripped my engine to checked the std piston crown measurement against my omega pistons the block is standard deck height i am in process of buying bits and was wondering on rods

[welshpug 1,622]

check the design specs of the piston vs deck height, and if you choose to use the diesel crank you'll need to make the rod shorter.

[dimmadave 0]

Std rod center to center are 158 iirc i ve sorced a 152 ill have to finsh my manifold and strip and do a mock build with the std rod to check the piston crown aganist the deck height wats the difference between mi crank n xud?

[welshpug 1,622]

152mm wont be much use if they are pistons for a J4RS.

 

xu10 cranks are 86mm xu9/xud9 are 88mm.

[dimmadave 0]

What would you suggest ?

[welshpug 1,622]

measuring the piston.

[dimmadave 0]

Cant see the omega pistons sitting below deck or sitting higher ive build a few forge engines and the pistons have sat flush with the deck

[welshpug 1,622]

that may be so, but which conrod are they designed for?

[petert 551]

The number you're after is 235.1mm, if you want the piston flush with the deck.

 

ie

 

half stroke + rod length + compression height = 235.1 (for an XU10)

 

eg

 

44 + 158 + 33.1 = 235.1mm

 

If you want less CR then have a 157mm rod for example.

[dimmadave 0]

If the xu10 crank is 86mm and the steel is 88mm on std lenght rods of 158 would sit the piston 2mm above deck so wouldnt it be

156 rod lengh? Which would mean custom rods i guess

[welshpug 1,622]

no, 1mm, 2mm is in the total stroke not half the stroke.

[dimmadave 0]

Oh yer lol maybe skim the piston then seem the cheap option i can can zrp rods for 240+vat for xu10j4rs unsure of custom length Price

[welshpug 1,622]

sod using cheap rods.

 

I'd sooner use standard rods. bushed to suit.

[petert 551]

If the xu10 crank is 86mm and the steel is 88mm on std lenght rods of 158 would sit the piston 2mm above deck so wouldnt it be

156 rod lengh? Which would mean custom rods i guess

 

Good question. On an XU10J4 for example, the piston sits 1mm below the deck. Thus

 

43 + 152 + 39.1 + 1 = 235.1

 

I can't recall on an XU10J4RS how far down it sits.

[welshpug 1,622]

not very far at all, they're slightly dished.

[petert 551]

not very far at all, they're slightly dished.

What sort of answer is that?

[dimmadave 0]

Zrp cheap rods ???

[welshpug 1,622]

decent rods start at £600 a set, stuff like Farndon, robson, carillo.

[Tom Fenton 1,525]

Everyone likes to talk down the "cheap" rods, but has anyone actually got any experience of use and/or failure?? I know the ZRP are used by a few race engine builders.

[welshpug 1,622]

not personally, I'm taking the advice of an engine builder, it's not hard to see where they will fail and its the damage they can cause if they do fail that you are preventing by paying not a lot more in reality.

 

its also not purely the failure byt the longevity of bushes and quality control, some were out of tolerance when new.

 

a good engineer could adapt some standard conrods very easily, cheap and plentiful, more than up to the task.

[dimmadave 0]

I dont think standards rods would be up to the task of 500+ hp even if mircopolished and shot peened