Tru2Chevy

Right on....

The aluminum L98's have 1.94/1.50 valves, however I don't know how much larger you could go on a 305. My motor still has stock size valves. I'm sure you could get away with 1.96/1.55 though.

Nope, just a little one. Can't afford to go fancy, just wanted a little improvement. Also had the intake and heads port matched (or ported, or gasket matched....all the same), and had the the valve guides cut for retainer to valve guide clearance.

FYI - total bill for all the head work (including above + dissasembly, cleaning, surfacing, pressure testing, re-assembly, and porting the intake) was $550.

- Justin

85_305

In previous "head" discussions, I have read I can do 1.95's on the stock 305 heads, but not sure the maximum size.

Can you please explain a "multi angle" and what it does?

Justin.. do you think that the $550 for your head work was really worth it?
-Matt

BTW.. what year Desktop Dyno do you use?

Tru2Chevy

I would do more research, and talk with a machine shop before deciding on larger valves. the 1.94/1.50's prolly won't choke a 305 unless you plan on doing a lot of work to it.

Well, I know that the work done was good. As far as power increase per dollar, I couldn't tell you. I had the heads done before they were ever installed on my car. And I can't give you current numbers yet, because I'm still finishing up suspension work before my car can leave the driveway. (According to desktop drag, it will run a 12.1 @ 109 - but that's just program, so we'll see how she runs when she's actually at the track.)

- Justin

Oh yea, it's DD 2000 that I use for my engine sims....

85_305

So are you implying that I needn't get bigger valves? By saying "they prolly wont choke a 305..", are you implying that the stock valve size is fine?

Well, I think I will take up that offer you showed me with the cam, rockers, etc, for 300 bucks. I will look into that when the funds allow

Tru2Chevy

I'm not saying that the motor won't benefit from larger valves, but with a relatively mild 305, the stock valves in the alum. L98's will be ok. They are a good increase over the stock 305 size (1.80/1.40...IIRC).

- Justin

85_305

But in general, would the 1.94 be a good upgrade for my stock heads? I am really leaning to stay with the stock head..

Tru2Chevy

You can stay with the stock heads and still make ok power....but stock for stock the aluminum L98s will give you approx 40 hp. The 1.94/1.50 valves will be a nice increase over stock, and there is not really any reason to want to go bigger on a 305 unless you are planning to go nuts with it (planning to run boost?)

- Justin

85_305

Well say I was to go with the L98 heads.. will that cam-kit you recommended to me still work, and get all the power gains you said?

Unless you call 300 hp, 350 torque nuts, then no, I am not going nuts. I am DEFFINENTLY not running boost, lol.. I couldn't afford forced induction EVEN IF I TRIED But I deff. don't want to pay $400 for heads.

85_305

And also.. what about the Performer EPS manifold? That is good from idle to 5500 rpm.. or should I still stick with the Performer RPM?

Tru2Chevy

Yes, the cam kit will still work. The second dyno chart that I gave you last week was with that cam kit and the alum. L98's. Don't expect to make exactly the power that is shown in those charts. That will vary depending on a lot of things. Remember that it is a computer program that is designed to approximate the power of engine combos. If you've got 150k miles on this motor, I wouldn't expect 260 hp from an intake and a mild cam....but it will still make a very nice increase in power.

As for paying $400 for a nice set of heads, just how much are you looking to spend, and what kind of heads do you think you are going to find for much less than that?

I don't know much about the Performer EPS manifold, other than I know it's only for square bore carbs (Q-jet, Carter, Edelbrock).

- Justin

85_305

Actually, I have 197k on the motor, lol. But why will it not make the same ammount of power?

I relize 400 bucks for a set of heads is unheard of.. but I would rather put less money into my stock heads, and have them be just as good as hopped-up, more expensive heads.

But.. with 197k on my engine.. and I have new valve seals, mind you.. do you think my engine will be good for much longer? What usually goes on an old engine first?

Tru2Chevy

I've seen small blocks last 300 or 400 thousand miles, as long as they have been properly maintained.

An engine that has almost 200k miles is most likely tired, and at least slightly worn out. This will cause a slight decrease in power.

Just an FYI - you will never be able to spend $400 on your stock heads and have them flow nearly as well as stock alum. L98 heads. The ports and valves are just too small.

- Justin

85_305

300 or 400k miles on a chevy smallblock? Wow.. that is a lot of miles! (Just goes to show the American Muscle!)

I can spend under $400 for porting, and maybe bigger valves, right? Would my heads be near L98 heads then?

Tru2Chevy

If you can find a shop that will port your heads (intake and exhaust side), cut them for larger valve springs, cut them for larger valves, and sell you the larger valves to go in them for $400, then I think everyone on this board will have found a new machine shop.

Even then, your heads still wouldn't be as good as the L98's. Not to mention the fact that you still have all the extra weight (about 75lbs total) of the cast heads as opposed to aluminum.

While the stock heads won't limit you from making some power, if you really want to take advantage of the cam and intake, you're going to need better heads. Even if they aren't the alum. L98s. I just talk about those because they are good heads, and they are pretty easy to find.

- Justin

85_305

Well, I will call around diff. places about the heads. If I find cast-iron for a LOT cheaper, i will go w/ them.. but otherwise, I will aim for the Aluminum ones.
I just thought that it would be a lot cheaper for a machine shop to do my heads, than to buy new ones