305RSlc

Hey guys, I am just about ready to go 350. I know I am going to do at least a 355, maybe a 383 depending on my funds. I have heard that power is made mostly in the heads and cam though. Well what I want to know is what heads I should go with. I have decided to go with the LT4 hot cam to start off with but I don't know which heads to use. Here are some options I have found

World products S/R torqers: 2.02"/1.06" can handle lift of up to .560", 170cc intake runner, 68cc

Cast Iron Vortecs: 1.94"/1.5" can handle lift up to .480", 170cc intake runner, 64cc

These two are about the only heads I have found that are under $400 a piece assembled. I am only going to be building a long block for the time being and just keep the TBI on it until I can save for a carb or MPFI. Which of those two would be better to go with? With the torquers I wouldn't have to change springs or get a new intake, but I would with the vortecs. However, the vortecs are cheaper assembled; but do they flow any better? I would go with the fast burns or some AFRs but right now I am just trying to get budget horsepower since it is my first engine build. (still gotta get suspension and rearend ) Shoot me some opinion or advice; some flow charts would be awesome as well. Thanks!

pskel350

the vortecs are nice, but you would have to get a new intake manifold to fit. i think either set would be really good on a street motor. IMO i would go with the world products, and maybe port them a little before you install them.

unknown_host

iTrader: (1)

I would go with vortec heads, a performer rpm intake for vortec heads and a 650 carb. I would also go with a more aggressive camshaft, the LT4 is pretty tame for a carb application.

kfoley

The vortecs will outflow the S/R's (stock replacements). However you will need a vortec style intake manifold. You'll have to get them modified for higher lift, SDPC sells them for about $320/ea ready to go,but you can find them on the net for much less (I bought a set for $500 one time).

unknown_host

iTrader: (1)

If you are really on a budget the only thing you need to do is buy a set of $40 kmotion valve springs, remove the inner dampers and buy a set of +.050 installing height retainers. Thats what I did, no problems at all.

MrDude_1

i would do niether.

a set of used assembled aftermarket heads is within reach.... even more so if you save up..

personally, even if it ment waiting another couple months, id save up a lil more and get some better heads.

305RSlc

Yeah I am aware the hot cam is a little small. But like I said, I am eventually going to do MPFI and am going to keep the TBI setup on it for now... so the 112 lobe seperation of the hot cam will be computer friendly,not the best thing in the world but it'll at least give me a 350 in the car while I save up for whatever induction I go with. Thanks a lot for all the help though.

How do the vortecs outflow the torquers if the torquers have bigger valves? That's the question that was in my head and actually sparked this post to begin with. thanks guys!

unknown_host

iTrader: (1)

Why, especially if he is going to be putting such a small cam in the motor? Vortec heads will be perfect for him, plus he can be assured that the valve seals, springs, seats and guides are all brand new and will have some longevity to them.

305RSlc

Yeah, pretty much what I was thinking....don't want anything to break on me right after I assemble it. If I decide to go carb, what kind of cam should I run? Hell, what would be a better cam for a mild 355/383 than the LT4 hot cam? Just trying to get ideas on the best way to spend some dough on power....and not more than $3000, looking for about 300-350 hp and plenty of torque to snap the heads of my friends(and probably the axles)

unknown_host

iTrader: (1)

Comp XE274 hydraulic flat tappet cam is perfect, with vortec heads and a carb it would make over 400 horsepower with 10:1 compression.

305RSlc

Anything that would allow me to go hydraulic roller? I know about roller cams than I do flat tappet so that is why I ask. What kind of carb should I run with the vortecs and that cam? Sorry if my questions seem dumb, i know more about FI and roller cams than I do anything else and I don't want to get into building something and not know what I am doing. Would a single plane or dual plane be better to go with for a carb. I have heard TBI benefits from a single plane, but is it the same for carb?

unknown_host

iTrader: (1)

Depends what you want to do with it.

My car is as follows:

Vortec heads, cleaned up with some porting, no other machining, stock valves, $40 K-motion valve springs, +.050 installed height retainers, comp flat tappet extreme energy 274 camshaft, stamped steel stock 1.5 rocker arms, 9.9:1 compression, std bore 350, Demon 650cfm carb w/ mechanical secondaries, Edelbrock Victor for vortecs single plane and hedman 1 5/8" shorties into true dual exhaust with an X pipe.

The car has run a best of 12.45 @110.XX on a pathetic 1.95 60 foot. I never got around to getting slicks or drag radials for the car, but it has 1.82 60 footed before in worse tune. So that would have been good for at least 12.2's if not 12.1X's.

If you really want to go roller, I would look into the extreme roller line from Comp Cams, but only if you plan to go with a carb (which I would).

My 350HO crate motor stock from carb (demon 650, edelbrock performer intake) to pan in excellent weather on radials went 12.93 @ 106 with full exhaust. There are several members on this board with the 350HO and TBI on top, and I havent seen faster times out of any of them...

305RSlc

Well I want to keep it streetable, and it is my daily driver. 12's in the quarter would be awesome. However, I do need to keep some street manners since it will be driven constantly, and I need a good cam that will create plenty of vacuum to run power accesories, especially a/c. I live in florida so I can't live without it.....although driving around at 60+mph with the windows down makes for some pretty good a/c Still though, I want to retain p/s, a/c, and have good street manners and get as good if not better gas mileage than my TBI.(17 city/about 25 hwy) However, with longtubes and a lopey idle, I would fall in love with it no matter how fast it ran. I love that muscle car sound.
unknown_host, could you shoot me a link to those K-motive valve springs so I can get the specs on them? I appreciate the help guys!

unknown_host

iTrader: (1)

http://store.summitracing.com/partde...=KMO%2DK%2D700

There are a few people daily driving the XE274, it makes enough vacuum where brakes arent a problem. Its not a small cam and its not a large cam, its as in between as you can get.

305RSlc

thanks a lot....but those only handle up to .500" of lift. Aren't the z28 springs the same outside diameter but can handle a little more lift? Either way, I'll check into those cams you have suggested.

kfoley

If you get the 274, I would reccomend getting the matching springs from Comp. Pn is 981-16 and you'll also need matching retainers (can't remember the pn on those).

305RSlc

I guess I'll just contact Comp and describe my setup and what I want to do with it and see what they recommend. I forgot to ask,
unknown_host, those times you posted with your setup, are those with your stock 2.73's? and what tranny? If you're hitting low 12's on 2.73's then I am definitely impressed.

kfoley

Just so you know, Comp is conservative when it comes to reccomending cams. Generally I would go a step up from the one they suggest (at least).

305RSlc

I will definitely keep that in mind...thanks for the heads up. I am still debating whether to go hydraulic roller or flat tappet. I am hoping to get a L05 and just use the lifters from that to keep the hydraulic roller cam.....hence my obsession with the hot cam. It's one of few rollers that I have seen that are quite good(I guess) But I am gaining valuable knowledge by just asking questions so i probably wont' buy anything till I know a little more.