Ireland engineering hd rockers and oem prices

[shaun_89]

Has anyone on here used these on there m20 and what opinions do you have of them?

They are coming back as the cheapest option at around £260

Steel newmans are £450
Stealers oem are £418 for 11(as i already have one)

Not sure wether to bite the bullet for the newmans or save some money and get the ireland ones...

[ross2009]

are you actually gonna be tracking it or racing it?

[shaun_89]

are you actually gonna be tracking it or racing it?

Its a track car

[ross2009]

well imo its worth it then if there gonna take the punishment
id go for the newman ones personally

[shaun_89]

Just rang gsf and they can get some for £9.37 ea

However they couldnt tell me who makes them...
Do they sell cheap repros or are they oe quality?

[Mikey_Boy]

I would beware anything that claims to be OEM that isn't OEM...!

Remember as well that you will have to pay import duty and VAT on the Ireland items..

[shaun_89]

Ive just rang gsf again but a different branch. The rocker arms they sell are febi/bilstein ones, are these oem ones?

[ross2009]

no there not oem but BMW do use febi I've just bought a set from gsf cost me 150

[shaun_89]

no there not oem but BMW do use febi I've just bought a set from gsf cost me 150

How do they compare to bmw ones? Ill be blending down the casting lines and shot blasting them if i got some standard ones anyways.

[ross2009]

not alot of difference I would have thought there both ali

[ross2009]

what this idea about flagging casting lines and shot blasting them I used to work for a casting company and personally that ain't gonna make a blind bit of difference that's only the surface that your touching if the integrity of the cast has air in it or bubbles then it's gonna brake wether you like it or not not that they should have co they can test that but flagging casting lines and blasting them isn't gonna change the structure of the casting

[shaun_89]

The idea is to remove any stress raisers on the rocker. I can do it for free so i might aswell give it a go. I know i cannot change the physical properties the cast. My bmw one that snapped had plenty of air bubbles in it, i was quite shocked.

[ross2009]

but you've got to remember they didn't have the tech to check 20 odd years ago ;)

[e21Jason]

cast and blasting hardens the surface and reduces the risk of cracking, a lot of the uprarted ones are OEM which are xrayed to pic the good ones then shot and peened

Jason

[DmcL]

i got a full set of 12 new rockers from a local breakers/parts dealer for about £120.

ive had them in the car for about a year and a half so far and have been revving the engine out to damn near 7000rpm for most of the time since then.

they recently got a new site up which is http://www.bmwspareparts.com/

i would say tell them daniel with the gold E30 sent u but i dont think it would make any difference on the price knowing him lol

[Mikey_Boy]

This is all excellent stuff - remember though that anything aluminium will have a fatigue life and this is key to why the alloy rockers break as well as the issues with castings etc.

Bead blasting etc will only have the effect of delaying the inevitable, which gets ever closer with increasing revs!

For real durability, steel is the only way...

Cheers,
Mike

[Gruelius]

the ie ones are "beefier" in the area where most fail, the part where the eccentric sits.

[HairyScreech]

cracks begin at the highest stress concentration point, which is nearly always a sharp edge on the surface, the surface is the furthest from the neutral axis in bending, so thus has the highest "leverage".

by removing the casting flash you are reducing any stress risers.

if you then go on to shot peen then, (not blast) then it will put a small amount of compression force into the surface of the material.
as things dont tend to crack under compression they tend to do it under tension, this small amount of compression at the surface reduces the localised tension and thus the chance of a crack developing.
the principal is similar to toughened glass.

surface finish is very important to cracking, as any defect on the surface is a stress concentration point.
think scoring glass or bathroom tiles before breaking them.

[DmcL]

think that about sums it all up right there haha

BTW welcome greu, never noticed u joined up here. hola gringo