Assessing Joe Dirt's work

[AMXguy]

My new project car came with a 440 in it that's sat for 20 years.

Pulling it down it's easy to see it had to be Joe Dirt who rebuilt it, every corner was cut and the entire engine was plugged with silicone.  on the plus side I have LY rods and a fresh ground steel crank. 

The 346 heads have new valves springs and keepers, the guides are pretty good .  but Joe ground the top of the guides down and put stock umbrella seals on which fit fine.  my question is did this  trash them ?   can I have them machined for positive seals or is it even okay for a street engine as is?

If I still have something to work with I'll send them off to be checked over but if they're scrwed up I'll just pull the parts out and toss them.

[Chryco Psycho]

Well 346 are nothing special , trimming the top of the guides is normal for higher lift cams so the retainers do not hit the seal or top of the guides , they can be machined for positive seals or used with umbrella seals on the street . exhaust is more critical to have adequate oiling to the valve stem .
Having said that I would use a closed chamber head over any of the open chamber heads , for the price of reworking the 346 you can probably buy new Stealth heads , you just need to swap to 10* locks & retainers & maybe swap springs to match the cam if you choose a cam out of range of the springs the stealth heads are supplied with .

[AMXguy]

The problem is I'm trying to keep the stock look with stock vale covers and HP manifolds.   will Stealth heads work with those?

Won't the closed chamber heads require a special piston to keep the compression under 10.5 for a street engine?  I've used KB hyperutectics with 906 heads the last few times and had about perfect results.

[Chryco Psycho]

The Stealth heads will look stock  & work with stock parts . alum heads need 1 point more compression to make the same heat / power , so closed chamber with aluminum works & keeps the quench to prevent detonation .

[AMXguy]

I'll look into those.

I running 1 point more compression I assume the octane would have to be increased accordingly?   I'm running 50/50 AV100 and super now and it seems to be just fine.  1 point more and I'd have to do something different I'm not sure a higher AV100 blend is a good idea.

[Chryco Psycho]

the closed chamber will resist detonation using quench & the Alum will absorb more heat & run cooler , you may end up with less octane needed

[AMXguy]

All things being equal what kind of HP gain could one expect?

[Chryco Psycho]

I have seen 10% or better on a simple head swap

[AMXguy]

Very interesting. thanks  I'm going to check it out.