easy way to upgrade Rods...???

[Bram]

can you really replace rods without balancing in this modern an engine?

I did not balance my rotating engine components after swapping in Scatt H-beam rods. The engine runs better after I changed the rods which could be due to the weight reduction of the rods (about 40 grams difference IIRC on each rod). Just make sure the rods are equal in weight (also at the ends) which they were from factory in my case.

I know it's not according to the workshop manuals and high spec tuners, but it seems to hold out just fine for now. However I do not revv the engine above 7000 rpm to avoid any possible issues, although I can only tell if it stays OK for sure after a rebuilt and check the mean crank bearings and other internals.

[Knight Rider S4]

Rather take the engine out!

Don't think there is a quick way to do this, can't see how this could be done without removing head?

I have done this job with engine in and you need a ramp for this or you will be **** ing round all day changing them over

Totally agree with Jamo ..If I was going to do this again ..I would rip the engine out have it on a stand and do it with ease ...Have the lot done in a day easy

[QuattroFever]

can you really replace rods without balancing in this modern an engine?

[Rocco]

wow, good explanations here


i´ve opened my engine 4 months ago with a mechanical friend and we have skimed the head + polished the ports + PK Motorsport metal head gasket 8´8:1 CR with ARP bolts torqued in 3 steps and 105nm i think

the enngine block,pistons,etc seems in very good condition... but unfortunately the Rods are continue going stock.... now i think that before with "few" more money now my engine with upgrade rods...

i am sad now,because i don´t want to open it again because run perfect and it has nothing of engine loses or leaks...

maybe next time... but i bought a AAT block and 7A perfect head..... and it will be better expend the money in this small rebuilt engine project..


thanks to all

-Tomas-

[repo]

The ONLY way is to remove a head.

Pistons do not fit down enough so you could remove the pin clip from the sump side.

[GazzaG60]

i left my crank as is in there. i did a few extra bits i didn't list to keep it to the precess asked about

i had my pistons skimmed to lower compression and winged it. had the machione shop remove and refit the rings. all cleaned and that. then built it back up myself. 20k on and its all well. revs smoother and the slightly lighter mass helps me at least think its reving faster.
i also did a new waterpump and oil pump at the same time. better once than twice.

its doesn't burn oil it leaks it lol

[S2central.net]

LOL - there aren't many jobs on the S2 we can truly say are easy... But this one would be a nightmare without removing the head.

Good advice from Gazza above and I third the suggestion for going to ARP head bolts at the time... And uprated conrod bolts as well for good measure.

Block shouldn't need honed unless renewing the piston rings... Not sure I'd remove/refit old rings so that the pistons can go to be weight matched...

Make absolutely certain to not mix up the big end bearing shells - keep them matched to original position - probably a good time to inspect bearing surfaces actually and check clearance with plastiguage

Oh and cleanliness is your friend on the rebuild !

[madpugger]

Removing the head is definitely the easiest way, but its still not 'easy'

Also, if you are putting in uprated rods, it's a good idea to do the head bolts too...

[Jamo]

Rather take the engine out!

Don't think there is a quick way to do this, can't see how this could be done without removing head?

how you would you change the gudjen pin and put pistons back in?

[GazzaG60]

agree on time. its the bloody sump and all those bolts thats a pain.

[Bram]

I think it's much less work to remove the head compared to change them from the bottom (I think it's a horror job). Actually you can change rods in 1- 1,5 days work, when taking the head off. At least that's how long it took me to do it.

[madpugger]

Agreed with Bram.

Technically you could remove the rods from the bottom, but you would need to remove the crank, which required removing the engine or gearbox, or at least splitting them. Then you have the issue of fitting the pistons back in.

I would do exactly as Bram suggests, far easier and less time consuming!

[GazzaG60]

you need to remove the head.

best way id say is.

1. head off
2. sump off.
3. remove rod cap and push rod and piston clear of bore. remove 1 by 1.
4. label them as you go.
5. get the rods. send them and the pistons to the machine shop for weight matching.
6. either have the block honed and fit new rings or wing it and ensure the rings are fitted back to the correct pistons.
drop in 1 by 1 like you removed. use a good ring compressor. i have the ARP ones in a few sizes.fit new shells. use engine lube on the shell surface meeting the crank.
7. buy some arp studs. fit those with a metal gasket
8. put everything back together.

job done.

a better chip will be easier on mechanicals but not enhance their strength. best to fit rods if you are close to the edge.

[Greg_S]

I thought it was possible, but you have would have to remove the subframe to take the sump off and unbolt the rods to remove them

[Rocco]

The change rods you have to take the cylinder head off. There is not other way to do it.

,in this way i will continue with stock Rods... ,and look for an other more reliable ECU setup


thanks for the info Bram