Im getting a new engine (still trying to look for a decent one, I think I found one)

an engine that has 310 hp, from a local store in my town, while im getting a new engine, I desided I want to swap a cam, a bigger one, that has a pretty rough/choppy idel, but still drivable street use.

My question is I want this Xtreme Energy Hydraulic Flat tappet cam, One I found off Jegs but it has a note saying

"We do not recommend the use of stock valve train components with these camshafts due to the aggressive lobe designs."

Does that mean I gotta swap out and put different vavle train in? if so, how much and would it be a big hassle?

http://www.jegs.com/p/Comp+Cams/746624/10002/-1/10707

My other option I sorta like is Im looking in my catalog from PAW and they have Comp Cam High Energy Hydraulic Flat tappet cams, and I found one that said this:

Lift:445"
Duration: 268*/268* 110 LC
RPM Range: 1,500-5,500
50 state Legal C.A.R.B Approved*
Good street performance with stock
cnveter, choppy idle.

(btw, I didnt mess up the word "cnverter, that is exactly what they said)

And that cam has nothing saying that I need to do anything with the vavle train.

So which one should I get?

which one is better?

 

Hm, Nevermind on the Xtreme Energy cam, I looked into it more in my catalog from PAW and finding out that theres alot to it, and High Energy would probly be a better choice (in my opinion) anyone agrees about that?

 

If you go to a nice, larger than stock cam, getting some nice valve springs kinda goes with the territory. And while you're at it... some nice rocker arms would be a good addition, but not necessary... etc.

Big cam = new springs. It's just the way it works.

You'll need to know the stats on the springs at the installed height on your heads and how that compares to what the cam needs. It's not hard, it just requires a few different (not that expensive) tools to do it.

 

Do you know the specs on that motor you're looking at? Cylinder heads and compression ratio would be most important to know at this point, but the more info the better.

You really don't need to do much for the milder XE grinds other than make sure you've got valve springs that are up to the task. But choosing a cam isn't something you would want to do by how the idle sounds. It's gotta be a decent match for the rest of the combination or you could end up making a dog out of it.

 

Also with that nice lopey idle comes some eprom tuning. Remember about all that stuff.

 

Picking a mild cam to avoid replacing valve train is a bad idea. You may as well just stick with the stock cam, you don't have to replace any parts then! Yay! None of that pesky extra HP to deal with
C'mon, get with the program here. Buy a "fork" type valve compressor for $12, and some 1.25" springs for $60, and then the cam you WANT. Make sure it matches your engine though (CR, convertor, heads, etc) and go to town.

 

Vortech iron heads,
Compression ratio is 9.5:1
Rocker arms are 1.5:1
the origanal cam they have in it is a Hydraulic Roller.
The specs on the origanal cam is:
Lift: .431"/451"
Dur @ .050" int/ext. 196*/206*

The cam I found out of my PAW catalog is:
Lift: .445"
Dur: 268*/268*

I havent messed with vavle springs, lifters and cam, and the other things before, Im not all too sure what would work, but I have an idea what would, and what wouldnt.

But like I said, Im still under a budget, and have to know everything before I buy, and I dont want to cause more work and more money for something, that I can probly find cheaper and easier.

 

There's more to a cam, as regards valve spring selection, than just the peak lift.

Stock cams have long, slow, easy, gentle ramps, that sort of ooze the valve open. That's why you can get more power by replacing them: open the valve faster, and you get more flow, more of the time, which equals more cylinder fill, which equals more energy in each firing. The Xtreme Energy cams are pretty much as aggressive in snapping the valve open, holding it as far open as possible for as long as possible, and then dropping it suddenly back closed, as their designers felt they could get away with.

Consider a wave of water when you're down at the beach or something. You could have a 4' wave that's a long slow gentle swell, or you could have a 4' vertical wall of water bearing down on you. Which one would you feel more? Your valve springs are pretty much the same way.

That's why stock ones ARE NOT adequate for ANY aftermarket cam; and ABOVE ALL, not for the push-the-envelope ones like the XE and the VOodoo series.

You don't want a "cheap" cam. Cams overall are SO CHEAP anyway, that it's pointless to spend a whole bunch of money on the rest of the motor (the expensive part), and then handicap it with an inferior cam. Penny-wise and pound-foolish: like moving dollar bills laying on the sidewalk out of the way to pick up the dime under them. In particular, the Vortec heads like an asymmetrical cam, with a larger exh lobe; the heads have all this GREAT intake flow that makes them what they are, but the same sucky exhaust port as any other stock head. THey respond to a cam that props up the exhaust a good bit, in relation to the intake. Look at the XEs and the Voodoo line. Rollers preferably.

 

I have a Flat Tappet cam for sale, Edelbrock performer plus. Go check out engine/valvetrain parts for sale. If you get a bigger cam also you have to have your guides grinded down for more travel. The edelbrock cam i have for sale is close to stock but has more lift and durartion...

 

Alright, then what are you suggesting? (apparently Im not getting what your talking about, sorry)

Yes the XE cams are nice, but then I have to work on all that like your saying, and what would I need to make it work, like different rocker arms? push rods? all of it? but would it be worth the work?

Wouldnt the cam I suggested work better, the High energy torgue cam. has good street performance with stock converter and has a choppy idle, and looks pretty good to me, and it doesnt say anything about requiring replacing the vavle train.

but if the XE works better and get more advantages, then what is it, and what do I need? if that cam isnt worth putting money into, then I will go with that cam I just said, or if it is worth it, what do I need? like ehat in EXACT is what im asking?

 

Well generally those things you'll have to replace for any cam swap. If you're going with a cam smal enough to reuse the stock pieces, it's not worth the trouble to swap it, but that's my opinion.

And I'd hazard a guess and say the HE cams aren't much different. They'll require you to swap at least the valve springs I bet.

 

I can understand I'd have to replace alot of it, but most of it? Im beleiving the rocker arms are self aligned, and what kind and specific kind would I need, and Im sure the HE cam isnt any better, but didnt say anything I gotta mess with changing my vavle train, and works with the stock conveter.

 

THe HE cam (I'm not going to do the research on which cam you're looking at and what their measurements are) will probably require you to change all the same parts the XE cam wants you to change.

Why not a roller cam?

 

:-\ Yeah... I looked into it a little more and its the same work... I think I know the parts I need to more it work. I have to see how much it all will cost and see if it will still be under my limit im spending on, because after I get the new engine, I gotta get a new tranny, and put bigger rear gear parts in.

 

Does this XE cam needs a 2000 converter in a manual car? (dumb question... but right now, my head is about to explode, sitting up late, going through catalogs and books, one solution with the HE would work buying the whole kit for it, but apparently it is used for a 9.1 or less compression ratio, and my engine will be 9.5.1 ratio, so I dont think its going to work.)
and would the XE cam work with 9.5 compression ratio engine?

Im sorry Im asking alot of questions, and sound clueless, but its a bit fustrating of what solutions I can go, but they dont add up any better then the other. not to mension, Im going to have to get a 5 speed tranny with a overdrive which I found one for $3500, and dont wanna spend that much, or get a 6 speed which would be a little cheaper, but not by much, and much more.

 

Depends on the cam what stall you need. Higher(numerically) rear gears will make a stockish stall easier to work with, vice versa. But since you've got a manual, that means absolutely nothing to you. Ignore it.

THe compression recomendations are more rules of thumb, but try to follow them because that's where they work the best. There is more than one xtreme energy cam and more than one high energy cam. You have to sift through and figure out how big you want to go.

$3500 for a 5 speed? WTF? You can get a T5 for $200. Are you talking an aftermarket 5-speed? A TKO or something? I just grabbed a T56 for $1200 with everything I need the other day. You can get LT1 T56's all day long for under $2000 and usually around $1000-$1500 and it swaps right over. DO NOT GET AN LS1 T56! You can make them work, and people have done it, but it's much easier to start with an LT1 T56, everything swaps right over for you if it's a 1 pc RMS block (it should be if it's a 91).

And why do you need a "5 speed tranny with overdrive" anyway? That doesnt really make much sense? 5 speed with overdrive is a 6 speed? Or do you mean a T5 where the 5th gear IS the overdrive? What's wrong with what you have?

Ignore the stuff about stall converters, you're using the clutch instead.

 

first of all do not buy a longblock

just get a shortblock w/flattops that does not come with a cam timing chain and oilpump

buy a nice cam and get a GOOD!! set if heads and put new springs retianers and locks in

if you can put a cam in you can bolt a set of heads down

do it however you like this is but a suggestion

 

I think that you should get the engine first. Think ahead, but dont get yourself AFU until you have a base to start with. After you have a starting point and know what you are working with, it's much easier to build from. A good set of roller rockers are a great investment. I would think you could buy shortblock with some nuts and an aftermarket set of heads for what your going to spend on the engine you described and a new trans. Put some power in the car, blow up stuff, then replace it!!

 

Man...this thread is a mess.

First off; the engine you're looking at has stock vortec heads. This probably means they're limited to .480" cam lift unless they've been machined. You need to find out more about the heads before you go any further.

Second, the High Energy or Edelbrock Performer cams are "ol' school" grinds and not very efficient compared to the XE line so I wouldn't bother with them.

Third, you mentioned the existing engine has a roller cam. IMO, you'd be silly not to use another roller cam. And if the valve bosses have not been machined to accept higher lift than stock on the heads, then I suggest the CompCam XR258H, but I would get it custom ground with a 114 deg LCA so the ECU doesn't have a fit. It's a step above a stock cam, still roller, and fits within the restrictions of the head lift limit, and also, I doubt you would need to get the ECU reprogrammed. Not to mention that you could get away with just a valve spring change. Stock rocker arms will still work with that cam.

With that cam and engine, you can easily get 325HP....but probably a little more depending on the exhaust setup.

 

That is the cam I got. Don't let the numbers fool you. It is a sleeper. The ECU will like it, idles smooth (550 rpm), good vacuum (17"), with the 383.

12-408-8 XR258HR 258 264 .480 .487 110°


Also look at the 08-300-8 262HR-12 262 264 .450 .480 112° Its a "stock ecm" computer cam.

or 08-500-8 XR258HR 258 264 .480 .488 112° "no chip change"

BTW I have several stock 350 vette's.

Quote SteelTownMadDog "It's a step above a stock cam" = bunches more power than stock.

 

No doubt. The XE line has pretty aggressive lobe profiles. I have the XR270HR in my 355 and love it. When I build my engine next winter (either 383 or 406) I'll be getting another XE roller cam, probably a XR282HR and use the same lifters.

 

I dont really need a 5 speed tranny with an overdrive, and the 5th gear has an overdrive on it, and it would work somewhat like a 6 speed, handles more torque I guess, but Im probly wrong about that.. like usal with alot of things. wow.. If I can find a 6 speed tranny that cheap ($1000-$1500) i'd so be on getting it. I've been having some troubles finding one around here. and alot of people tell me the stock 5 speed tranny can only hold up to 400 tq, or 280 horsepower then it'd snap... I dont really know if its a fact or not, I dont know much about trannys.

I've decided maybe rebuild and engine that will work with that cam, and I found it raither cheaper then having to buy a crate engine for $2500, and then redo the whole vavle train.

I apperatate your guy's help, and some.... I dont.... Im sorta burned out, and pretty confused, but slowly understanding it more and more.