Installed my AFR 205s in the spring of 2006 and I have 33k miles and close to 400 track runs on them so I think I'm due for some new springs. I've already bought 1.7 Yella Terra rockers and Morel lifters and now I'm looking at which valve spring to go with. My lift is only .600 so I've maxed out the current springs and AFR says to go to the higher lift spring with roller rockers.

I could just replace my existing AFR 8017 .600 lift springs with the AFR 8019 .650 lift spring or I could get some PAC 1521 .700 lift springs. I'm assuming that the 8019 will just drop in without changing the titanium retainers, locks, valve seals... Or should I change them as well? If so shouldn't I just go with the PAC 1521 spring kit and replace it all? The money isn't the issue...the best thing to do is.

I run NA and I think I'm not going to get much more out of the heads as they stand. My 454 rwhp is the best I've seen on a NA 2004 LS1 stock bottom A4 GTO. So the other thing I've been told to consider is to send the heads off to be worked over to get some more out of them and just have the valve job done on them at the same time.

Opinions???

 

All you'll need is the PAC Racing 1221 spring for that camshaft profile. Ask me how I know.

 

I am running the AFR 6016 cam, same duration but slightly less lift (0.588) with the AFR 8019 springs and YT rockers. No issues. Not sure what is required to swap to the PAC's, i.e., not sure if you need new seats, etc. I would check with Tony or AFR with that question unless the folks at PAC are familiar with the AFR hardware.

 

8019's are a drop in upgrade; don't need new seats & retainers. As far as re-working the heads; since cash isn't an issue, why not? I'd send them to the source that knows them the best, AFR (Tony).

 

If you didn't I don't know who would. lol

Ok figured that on the 1221, I know I don't need the .700 lift but why not get the spring with the nitriding and Nano Peen processing since it extends the springs life. ... and maybe a little bigger CAM needs to be discussed at some point.

 

I know the extra processing does add to the reliability but the regular 1221s are used in every camshaft profile in the same series as yours. If you step it up, we need to consider a cylinder head swap too... What are you planning now?

 

I'm feeling restricted. Thinking maybe a few more cubes are in order.