Prs/Cons of uprated valve springs and retainers

[A80Avant]

Being in the process of slowly building up a separate cyl head( thanks spink), i am trying to source some parts for it. I am going to use stock valves and replace the hydro lifters with new ones. BUT i dont want to use the same springs,as they have done 200K kms, and as a precaution i prefer to replace them. Same with the retainers.


I know that every supplier of springs say that the uprated ones are good for higher revving engines. What are their cons though, and would they be required if you are not revving much past 7300rpm anyway?

ON the other hand, where can one find OEM springs( other than stealers)?

Finally, similar question regarding retainers. Do we need titanium ones? if so, why?

If not, where can one find OEM new retainers other than stealers?

[Jamo]

Uprated springs are for high lift cams, in a stock revving and stockish cam lift they will SAP HP so you will lose power

Ti retainers, allow for lighter top end however they wear significantly quicker than OEM

The light OEM hydro lifters like 034 sell are the only things I would consider

[A80Avant]

yes, i use the lightweight lifters at the moment. Trouble is that i cannot find the stock springs or retainers on any shop atm, and only uprated stuff. Anyone knows a shop that can provide these other than the stealers?

[QuattroFever]

cryo treating retainers can lengthen the life a little if its an issue.

[A80Avant]

I agree, but cryo is best done on new parts.

How about treating a cyl.head post porting?

[terrybullwon]

http://www.guy-croft.com/viewtopic.php?f=2&t=1847

[QuattroFever]

I agree, but cryo is best done on new parts.

How about treating a cyl.head post porting?

Not sure. It relieves stress so may help avoid cracking, especially after any machining work. I guess you would do it before the final skim though.

Apparently can lessen the amount of expansion so not sure how that might alter the torque specs for the head.

Was going to try it on pistons for that reason. So i could run tighter clearance and reduce wear on cold starts. Wasnt brave enough though.

[Audi-Porsche Avant RS2]

Hello friends, what do you think about this spec head under a engine block with Pauter rods and Je pistons, but with a hybrid K24/7000 or 7200 or SMS turbo?

Lightweight lifters;
Titanium retainers;
Hi-rate valve springs;
3rd angle valve seats with swirl polished valves;
Intake and exhaust ported and polished;
New valve guides and Viton stem seals;
ABY inlet cam 7A exhaust cam

Can I have problems? Is better if I use also ABY exhaust cam?
If yes can I use ABY exhaust cam with the rest of the parts of this head or not?
Sorry for my, probably stupid questions, but I'm new in this kind of work on the head.
Thanks!
Alessio

[A80Avant]

I am not that brave either, but ill ask around.

I'll start getting the parts for the time being and stick to OEM parts for now

[Audi-Porsche Avant RS2]

In my setup I don't know if with this kind of head can I have some benefits or is better that I stay OEM too.
Alessio

[V6quattro]

In my setup I don't know if with this kind of head can I have some benefits or is better that I stay OEM too.
Alessio

I don't think it is wort the afford and money for such a small turbo.

[Audi-Porsche Avant RS2]

In the future is probably that I mount bigger turbo, my question is if with this head can I have a good setup, better than OEM head with these small turbo too or not and is possible that I have some problems, especially with 7A exhaust cam that is for engine with a lot of hp and I don't know if I can change 7A exhaust cam with a ABY or ADU one without change the rest of the head.
Thanks!
Alessio