I've been watching this story unfold, anxiously awaiting the eminent "mushroom cloud". Glad to see that didn't happen, good job keeping your composure guys!
Anyway...mitchell, you asked about the heads and intake. Those RHS heads the OP wants to use are a Vortec design. And per their description "The dual pattern intake will enable you to use virtually any intake manifold". So, with their heads, you can use either a conventional or a Vortec intake manifold.
I have to wonder if their runner dimensions must be a little different from GM's heads though. The runners on a GM Vortec head is considerably taller than a conventional head. You could alter the angle of two of the mounting holes on each side of a non-Vortec intake to bolt it to the Vortec heads. But unless you weld more material to the top of the runners on the non-Vortec intake (and have it machined flat), you'll be left with next to zero gasket mating surface between the two, which would mean a blown intake gasket is a very likely thing to happen. The way to get the most benefit from using Vortec heads is by using a matching Vortec intake.

 

+1



I was watching this thread just waiting for it to explode. It was great that you guys didn't let it get that far.

 

I'm pretty thick skinned, I just don't like being flat out told I don't know anything on the open forum.

Mitchell seems alright though, I'm not holding any grudges

 

Oh, nobody would say that about you....as far as you know!
I gotta hand it to you though, you do seem to know quite a bit for being such a young tyke.

 

I get told that quite a bit, but I don't let it get to my head. I think that's where a lot of people in my age group get into trouble. As I said before, I know I'm inexperienced, and I have an enormous amount of information and experiences yet to be absorbed.

However, I can wrench just as well as someone twice my age. I might not know quite as many tricks, but anything mechanical (even if it's something I've never done) comes natural to me. Then if there's a subject or a concept that I don't fully understand, I educate myself by reading or asking someone that does know, rather than blow smoke.

Of course automotive does come easy. I do a lot of work in the hydraulic industry, specifically industrial and marine. My father's company specializes in Mega Yachts, and that's a whole different world than doing a set of brakes or a top end.

Now, sorry for completely derailing the OP's thread

 

I think I am responsible for destroying the OP's thread... oh well sorry guys. Perhaps I shouldn't have been so antagonistic in the first place. And thank you good sir for not holding a grudge, I find myself acting pretty arrogantly sometimes (something I ought to work on). You remind me a lot of me 3 years ago except you are less prideful than I was and on the fast track to becoming much more knowledgeable, just never let it go to your head (that's when the learning curve flattens out, trust me I've let my small trivial amounts of knowledge go to my head enough times to know, and I was snapped out of it time and again by a more experienced tech/car enthusiast putting me in my place)

 

Honestly I don't believe that particular cam would respond that great to 1.6 ratio rocker arms, It's lift is already proportionately high compared to the duration and overall valve overlap. plus a lot of heads need to be machined for that much valve lift. I don't THINK it'd really make a noticeable difference in your engine, not worth spending the money anyway IMO. but look at your flow numbers on the heads, (if you can find them) if they flow just amazingly at and above .500in valve lift compared to down low then it might be worth it, but remember the cam only peaks once, so peak valve lift flow numbers aren't as importance as mid lift numbers (valve passes them opening and closing), so duration is key, especially at higher valve lifts, that is why nothing beats a roller matched with some nice heads for good streetable performance. (the duration and a given valve lift is higher with roller cams than with flat tappet cams, the trade of is the ability for higher rpms, but you aren't looking for THOSE kind of rpms)

 

That's not a whole lot of cam compared to some in my opinion. With the 1.6 it should put him .528/.536 and with an abdc of only 61 he'll still have a good low end torque (hence the powerband starting at 1600)*. Duration and ABDC can give you a good indication of how a car will perform in the low end. All lift does is help to unshroud the valve seat to feed air into the cylinder which is more for the top end in my opinion. The engine valve events are what dictate how much air it pulls in. Where the valves open in the stroke also tells how much air it pulls. With a smaller dynamic stroke you would want a higher lift to allow it to pull as much air as possible during that short amount of time. With a longer dynamic stroke you don't have to worry about it near as much unless there are huge amounts of lift involved IMO. At least this is how I've always been told and done.

*> I was running a 280h cam with stock 882 heads (2.02/1.6 valves) and 1.6 roller rockers. The 280h cam was .512/.512 lift with a 280 duration and 66 ABDC and I still was easily around 300hp and decent low end torque that was verily streetable with power brakes. So my duration was a lot more than this cam and I never noticed any driveability concerns. I think he will be fine with this as long as the heads have a decent runner to help with the top end RPM's.

 

the 882 heads flow great at lower valve lifts but not as well up high, they are great heads for lower end torque and throttle response for that reason, that is if matched with the right cam (and the smaller ports keep velocity high). Like you I'm not as much worried about his engine responding poorly, i just don't think any gains would be very noticeable, his best bet would be a cam with a little more duration if he's looking for more power imo, but that will take away from his low end. Then he could always advance the new cam a few degrees to get a little low end back. *shrug* could be worth it though, it really depends on the heads and how they flow. mine has 276* duration and closes at 66* after bottom dead center and i have no problem with low end, i can't get off the line cuz of wheel spin. mine doesn't have much for power brakes though.


to the OP:
I don't know the flow numbers for those heads, but if you want a little more power and you want to keep your low end, a good camshaft range for you would probably be around 225* duration @.050 111-112 lsa and a 106-107 intake centerline. I also think a dual pattern is better a little more exhaust duration for better scavenging of the cylinder. if you want bigger power lift and duration numbers need to go up but this will likely effect the low end negatively, a higher intake centerline will push the power curve up a little, the peak will probably stay about the same. if you want a more peak power you want a tighter LSA but that will negatively affect the "broadness" of your torque curve. for a broader torque curve you want a wider lsa but your engine will peak lower. something like that, hope it helps, i don't think 1.6s will make a noticeable difference in your engine, i switched from 1.5s to 1.6s and it didn't make a difference at all, i switched to a cam with a tighter lsa more duration and about the same lift and it did much better.

 

btw i'm not trying to sound like a know it all. rereading my posts sometimes i do, just keep in mind these are my opinions. the cam i described is what i personally would use with those heads in a 350 based on my previous experiences.