Whats the best head for a stock 1992 l98 350.. RHS the #12407 with there 1.9 1.5 valves or the 12410 2.02 1.6 ? ? Thanks,

 

"Better" always depends upon what you're building. I'd just get the 12407 heads and stick to the smaller valves. 2.02 is overkill, unless you're doing all of these three things:

1. porting or changing the intake manifold
2. porting/deshrouding the heck out of the heads
3. getting a high duration camshaft grind

and the big number 4 must come into play, too--when you do these three things, you're usually also adding displacement, by stroking the 350 to 383 or 396 cubes, to get the most out of the higher flowing top end. The key is making your setup mesh, so it performs optimally.

 

It all depend what you want out of it and how big your wallet is.
I bought the EQ vortecs off ebay cause there easy on the wallet and they a seem to be a quality head to me.

Or you can buy AFR 195's and have the best street head around but those run like 1400 or so.

 

Let the head debate begin...he he he.

 

The correct answer is the 1.94-valved heads, because the whole point of the TPI is to ram extra air in at high velocity, and the larger throat that goes with larger valves will reduce the velocity. Counter-productive.
AFR 195s are not the best street head. The 180s are better, and are good enough to feed a 400 to 6500 rpm and 530 horses, so no need for a 195 head on anything less than a 434.

 

Wow.. Think's, It looks like i will be going with the small valve head. I noticed a lot of people get the small valve head and then add a 1.6 for the exhust valve...What effect does this have on the power band?

 

done correctly (there are very many wrong ways, very few correct ways) It helps power at upper RPM, moreso with short-runner intake manifolds, like the popular HSR.

 

To better these RHS Heads... I was thinking stock size valve's, but polished and under cut. Or would this have some kind of ill effect? And ps all you guy's have been a great help with picking my new heads! and i have to call out Atilla the Fun as i have bothered this guy to Death and he's Been a GREAT HELP! Thanks Guy's

 

Manley Pro Flos or Street Flos are good valves, but the gains in flow would probably not be enough to be noticeable, unless you port the heads and get a more radical cam. Again, everything needs to work in conjunction, to see a huge improvement.

It's always a money pit.

For example, if you're going to use bigger exhaust valves, then you'll want to change the cam specs to maximize the larger valves....when it all comes together perfectly, it performs optimally. It doesn't do as much good for a camshaft that is designed for a certain head setup to have more exhaust flow, when you can match a camshaft to the higher exhaust flow, for optimal performance....example-higher duration on the exhaust lobes, since you have more area to move the exhaust gasses.

And with heads, nobody can say that AFR 195s are "better" than 180s or vice versa because it depends on what the displacement, cam, etc. is. A well matched head of a lesser brand will perform better than an excellent brand that is not matched to the rest of your setup, even though the excellent brand is a higher quality product.

Dart and AFR make excellent heads. RHS heads are really good, from what I've heard and read. I've found that a lot of "old school" hot rodders swear by the Darts.

As long as you take your time and match and tune everything properly, the RHS heads will be great on your engine.

I'm still trying to maximize my LT1, with the money I will be able to spend on the darn thing. It takes time, but it's worthwhile to do it as right as possible.

 

Yes, I agree.. That's why im asking so many question, i want to do this right, and if i needed to spend a little extra on some better valve's them i was cool with that.

 

It's good to ask questions. There is always something new to learn every day, for all of us. It's a lifelong thing, really.

Stick with the stock valves.

Excuse my previous babblings--In a nutshell, once modifications are started, it's like a chain reaction of mod after mod after mod, to make everything work together. It sure can get expensive. It sure is fun, though.

 

These valves are worth it : http://www.competitionproducts.com/S...ductinfo/8430/ do not stick with stock valves. You'd be giving up most of the advantage of these heads. When you get these valves, hand-lap them using a new black marker. That'll let you see how big of a 30-degree back cut to have the machine shop to put on each valve. Ignore the guys who have NO experience with flow benches. Their advice is just guesswork.

 

I didn't mean use the stock valves from your old head or anything. I just meant use the valves that RHS puts into the head, if you're buying the assembled heads, as long as they are good SS valves. If not, Atilla seems to have found some good valves for you, at a good price.

 

Ok, That sounds like a winner combo..thanks for the help.