Hey guys I just got a set of 081's off ebay for 100 bucks.
What can I do to build these up to get the MOST power out of them that I can.Aside from porting and polishing (which is a given.)I know that the heads will need to be machined to accept the larger lift.What type of springs,valves and retainers would work the best.I will be using an LT1 cam with 1.6 rockers.What can I do guys?

 

3 or 5 angle valve job

 

If that's all the cam lift that you plan to run stock dia. springs of good quality will work. Do the heads have the valves with them?

 

If you are already going to port the heads and you are set on the LT1 cam than I would just run a spring that matches the LT1 cam (comp 981 for example) and be done with them. If you want more I would back cut the exhaust valves, have the guides machined so that you can run a positive valve seals with .480+ lift as well as having the pressed in studs removed for screw in studs. If you want to run a larger cam in the future the machine work mentioned will be required.

If the heads do not have valves in them now you may opt for larger ones. However, Dewey has already proven that you can make over 300hp with the stock valve size. A valve job and port work go a long way on all 305 heads.

 

A little exhaust bowl blending will do them well. I had that done on my 416 heads.

 

Well I already have the heads at the machine shop.They are getting a 3 angle valve job,the 1.94 and 1.54 valves from my 906 heads,and a full valve grind on both the int. and exh.I know that I need to machine the heads to except a higher lift. I think a .550 lift would be a safe bet.I'm still debating on using the LT1 cam.I've been contemplating a ZZ4 cam.I will be doing some home porting myself.(I'm practicing on my 187's off my 92) I want to get some more flow from the exhaust.I know that they only flow about 110 on the exhaust.if I can get about 170 or 180 I'll be happy.I would like to get 200+ on the intake.I WAS thinking about getting beehive springs,are they any good?

 

anybody else?

 

come on I KNOW you guys can give me some more clues on this.

 

You can run behive springs (I believe they make a set for stock srping seats) but I would just run normal springs that match whatever cam you choose.

 

one more question I have is I did use the valves from my vortec heads.The valves were the same diameter and length.The only differance that I could tell in them is that the original valve locks were a single pattern and the vortec ones had a dual pattern.would going to different locks be a problem?

 

Don't know why it would be a problem, if they work, they work. I've got a questoin for you though, maybe I missed it, but if you have Vortec heads why are you not using them?

 

I'm saving those for my 350 that I'm building up.I'm building up the 305 just for giggles.plus it's still pretty fresh so why throw away a good starting motor.the 350 is going to be my beast.but first I'm going all the way with the 305.I want to push this motor to it's absolute limit.Balanced, blueprinted, stroked and fully port matched.yeah it's "waste of time" when I already have a Vortec 350 but the experience for me is very well worth it. I love doing this stuff,it's not about "economical suicide" as so many have put it.Just the sheer joy of working on my engines and learning the things that I have learned from this site is the best.

 

plus I wanted to use as much "305" parts as possible.

 

I definitely respect that. The most you'll ever learn about an engine is when you tear it down and do some major work on it. Good luck! That's a big reason why I tore into my 305 as well.

 

I have been considering the ZZ4 cam does anybody have any good idea what springs would work well with this? I have also been told ,correct me if i'm wrong,but the ZZ4 engine is basically a carbed LT4. Would ZZ4/LT4 head components work with my 081's i.e. springs,retainers,and caps?

 

bump again