i was on the under standing that 2wd and 4wd rod's are different,


But i stripped my Fiecos engine, and found some 2wd rod's i've had sitting around for years, and the part number on the side are the same.


The only difference is above the grudgen pin (sp) on the 4wd rod's there's alot more metal? So Wieght/balance.


Can anyone clear this up?


The number on the sides of all the rod's are 'X YN00002'



Cheers Danny.

 

What weight is etched into the bottom?

4wd ones seem to be more likely to be an "H" from what ive seen, but Im not convinced there is a hard and fast rule.

 

all the rods are the same on either 2wd or 4x4 as are the cranks,no difference what so ever,

 

something to do with offset dimensions to lower piston slap??

 

on the pistons not the rods,why do folk try so hard to distort the facts on this site by posting stuff they dont know about?

 

Thats the pistons not the rods though surely?

 

He wasnt trying to distort facts, he was trying to help.

And now that me and you have both corrected him, it makes this thread useful, thats the GREAT thing about this site, if crap does get posted, it normally gets quickly corrected which helps dispell the myths

 

Just to confirm, on the Cosworth Racing website they list ONE type of YB rod only:

Catalogue » Heritage » YB Con Rod Assy » CON ROD (YB0023)

Product
CON ROD (YB0023) £150.00

http://www.cosworth.com/shop_item.php?productid=138

--------------------------------------------------------------------------------

 

now i think about it obviously i am wrong. be silly to design a bent rod. still would like to know how the piston design is different.

 

there is one rod type as doug says but there are also matched sets ie heavy and light ones if you have unmatched set get them end to end balanced

 

Thats the only difference i could see, was the wieght.

 

And standard of course.

 

Just checked the rods.


They all have H engraved on the top and the cap.

The top of the rod meterial differ'd from

9.3mm = 4wd,
5.9mm - 7.75mm = 2wd rods.

Also wiegh'd them,

Caps wiegh 158 - 167 grams, Rods = 463 - 474 grams, both together in they sets 629 - 633 grams.

But one of the 2wd rod is the same wieght as my Fiecos 4wd rod, for the cap, rod and complete set.

 

Thats assuming someone hasn't had the engine apart before you, and put an un matched set it......

 

The 4wd rods are all the same.


But the 2wd rod's come out of a rebuilt engine that a mate rebuilt. Which did have a new rod fitted on No 4, but looks like it had a another rod before that, as had 3 different style of part number stamp marks.

 

That could be the difference ....... a couple of rods from a "heavy" set, and some from a "lighter" set.....Basically four rods, from the same engine would normally appear identical to each other.

 

So, Have the lighter set got 'L' engraved? or any other I.D marks?

 

Rods other than weight .... yes, Cranks... no!

 

interesting thread this!!

 

edited.

 

the cranks are different-

the nose of the crank that the crank pully goes onto is slighly tapered on the 4x4

 

Cheers,

i noticed that a month a go, when i try fitted my escos front pulley on a 2wd crank.