Cam choice for 350 with Vortec heads [Archive] - Chevelle Tech

: Cam choice for 350 with Vortec heads


midnight1961
Jan 15th, 12, 1:44 PM
Does this look like it would be a decent performing cam for a 350 with stock Vortec heads ?

http://www.summitracing.com/parts/LUN-00016LK/

The engine is a 1971 350, has headers, Holley 600, 2100 stall, 3:31 posi gears.

Any suggetions or comments would be appreciated.

MrBill66Malibu
Jan 15th, 12, 2:05 PM
If your goal is not to have the heads machined for the 470 lift capacity and a good low end torque motor then yes that is a good choice.

midnight1961
Jan 15th, 12, 2:13 PM
Thanks Bill. I really don't want to have anything done to the heads. Just looking for something that matches up good with what I have. This car is just a cruiser, but low end torque is what I'm looking for.

docwilcar
Jan 15th, 12, 2:52 PM
That Lunati cam is about the same specs as the old comp 268HE cam and will work fine. Isky 264 Mega cam is similar with 216-216 dur. at .050, .450 lift on a 108 lsa which would give you a little better low and mid range in my opinion. If you want a similar cam with a rump rump idle you could use the old crane 274H06-218-218 .450 lift on a tight 106 lsa. I have this cam in my 84 Vette and it has tons of low and mid range and the nasty idle at about 700-800 rpm. It works with stock springs too. There are quite a few people using this cam. Elgin makes a copy of this cam under part# E1785PM and is around $100 including lifters from competitionproducts.com My 350 has the stock small valve heads, 8.5 c.r., edel. 600 carb on a zz4 intake, factory tube headers and true dual exhaust with no cats, AT, and a 3.07 rear gear. The Lunati cam will have a slight lope to it, the Isky a little more lope and the 274H06 quite a bit more. It is an old circle track lift rules cam Crane used to call the "saturday night special".

grovey
Jan 15th, 12, 2:56 PM
i had that cam installed in a 305 ho. i wasn't impressed.

midnight1961
Jan 15th, 12, 3:04 PM
Thanks Greg. I'll check into the cams you mentioned. What heads do you have on your Vette ? The ones I'm swapping out for the Vortecs were the stock 882's.

RB69SS396Conv
Jan 15th, 12, 3:34 PM
Wrong cam for those heads.

The thing that makes those specific heads different from any other SBC head, is the INTAKE ports. They moved them so they have all this wonderful FLOW. So think about that: lots and lots of FLOW, all this stuff going INTO the cylinder.

But.... (there's always a "but", eh??) they didn't do ANYTHING about the exhaust ports. They have the same sucky restrictive exh ports as any other SBC heads. Therefore, NO FLOW going out.

Therefore, it isn't hard to see, they can use all the help they can get on the exh side so that the flow IN and the flow OUT are more nearly balanced. They'll respond HUGELY to a cam with a bigger exh lobe than int lobe; something that will "crutch" the exh side, so to speak.

Look at the modern asymmetrical cams like the Comp XE and Lunati Voodoo series. Both of them have cams with about that same size intake lobe (which is a good choice for the rest of the combo), but a MUCH larger exh lobe, which makes a DRAMATIC difference to the overall results you will get.

midnight1961
Jan 15th, 12, 4:12 PM
Look at the modern asymmetrical cams like the Comp XE and Lunati Voodoo series. Both of them have cams with about that same size intake lobe (which is a good choice for the rest of the combo), but a MUCH larger exh lobe, which makes a DRAMATIC difference to the overall results you will get.

I dont think any cams in either of those two series will support the max lift of stock Vortec heads which I think is about .470 lift. I really didn't want to have to do any modifications to the heads.

65 Skylark
Jan 15th, 12, 6:45 PM
Comp Cams XE268.

midnight1961
Jan 15th, 12, 7:31 PM
Comp Cams XE268.


Lift .477" / .480"

Pretty sure that is out of range for stock Vortec heads

65 Skylark
Jan 16th, 12, 6:19 AM
Lift .477" / .480"

Pretty sure that is out of range for stock Vortec heads

You're right, I actually meant to put XE262. Sometimes my fingers don't do what my mind is telling them to do :) I had an XE262 in mine for a few years and it is an incredible street cam, great torque, wide power band and good manners. I've actually thought about putting it back in.

Yellomalibu
Jan 16th, 12, 6:53 AM
I am very happy with the Elgin E-923-P in my DD Blazer with a 350, which sees some towing and is about 1000lbs heavier than a Chevelle and has a stock converter. That cam is 270/280 advertised, 204/214 @ .050, 107/117 lc, 420/443 lift.

For the OP, with a lighter car and a bit of converter, I think the next "bigger" cam would work well: the E-922-P, which has 288/298 advertised, 214/224 @ .050, 443/465 lift, 112 lc (probably the same 107/117 split - don't see it on the website I'm looking at)

RB69SS396Conv
Jan 16th, 12, 7:43 AM
Those are both completely generic, "universal" cams. Can be had most anywhere for DIRT cheeeep. Been around for 35 years or more that I know of. Very "low tech" but easy on parts since they were designed way back before you could really buy valve springs in the variety you can now. Won't win any races but as said might be satisfactory in some situations.

http://www.summitracing.com/parts/SUM-1102/
http://www.summitracing.com/parts/SUM-1103/

The first one is what people often mean when they say "the RV" cam, the 2nd when they say "the mild" cam.

Yellomalibu
Jan 16th, 12, 7:55 AM
Thanks Bill. I really don't want to have anything done to the heads. Just looking for something that matches up good with what I have. This car is just a cruiser, but low end torque is what I'm looking for.

This is what I had in mind when I posted. A stretch to call either of the cams I mentioned "performance" cams, but I suppose both of those mild or RV cams are higher performance than the stock cam likely is/was. :)
The 350 in the Blazer was a 92 TBI engine, and the E923P is "larger" than what it came with. It has a smooth idle, plenty of low end torque, and gets 16mpg on the highway with a 600 vac sec, 3.08 gears and a 700R4. From what I hear, that's not too shabby for a C10 Blazer.

jeff swisher
Jan 16th, 12, 8:55 AM
I will add some for you...Stock used springs suck..stay with a "lazy"
cam unless you change springs the upper R's of some of those cams will not be there.
If you are happy with 5000-5500rpm then I would look at what you originally posted.
I have ran the 268HE many times, even with stock springs,,great mileage and performance,,you get the isky or others in that same size ground on a 108 or 106 they will pull a bit harder but the mileage will suffer by a few MPG.

I have got 20.5 mpg with the 268HE in a 78 nova with 308's and a th350
grind it on a 106 and i get 14mpg and this is with more compression to boot. 210psi cranking pressure

But the later runs 13.51...with a lot of gear in it and good springs shifting at 6000-6500.
Are you installing the heads yourself?
Are these already installed?
Sometimes a spring and retainer change is all that is needed to run higher lifts.
This is something easily accomplished in the garage or kitchen. :thumbsup:

Slick71ss
Jan 16th, 12, 11:40 AM
My pick for what you want would be this Voodoo cam...

http://www.summitracing.com/parts/LUN-60101LK/

You can run a little more lift if you're willing to purchase budget performance springs and either use a different spring retainer or modify your stock retainers. You can buy Howards 98214 valve springs for $30 and grind 1/16" off the bottom of your retainers and then safely run up to .500 lift. You could then step up to something like this Voodoo cam or similair...

http://www.summitracing.com/parts/LUN-60102LK/



I ran this combo on a stock 350 with stock Vortec heads...

Howards 98214 springs (don't use inner dampner spring) $30
Modified stock spring retainers
Elgin cam & lifter kit E1015M $107

Lift: .465/.488
Duration: 298/304
Duration @ .050": 224/234
Lobe Separation: 112 LC

That combo ran good for a dirt cheap, budget build. If I did it again I would use the Lunati Voodoo 60102 cam kit.

midnight1961
Jan 16th, 12, 3:16 PM
Thanks everyone for the advice. Thats what makes this site great ! I'm going to go over all the input given here and make a choice this week.

Thanks again !! :thumbsup:

BowtieAaron
Jan 16th, 12, 4:46 PM
IMO is spend $300 bucks and have the guide bosses cut down and buy different valve springs, that way you can use those heads to its potential and if you plan on swapping dams later you can.

I ran the xe268 for years. It worked nice even with a stock converter.
I currently run an xer282hr114 in my ls1 it's 224/230 588/590 lift on 114. This is my daily driver. I lost 1 mpg average and stayed same on highway. Coupled with headers I picked up 75rwhp.

I also run right now a 231/239 282/290 on 110 576/590 lift cam in my. 180cc headed 355.
With 355 gears, 26" tire, vacuum sec carb, dusk plane Holley I get 23.5mpg on highway with the old Muncie. Around town I hammer it so I'm not sure what the mileage is, but it's better than my gto. So prob 15ish avg.

I almost forgot to mention. My 231/239 drives almost as nice as my 224/230 on 114 in my gto.

So for what it's worth. I'd put atleast the xe262 or 268 in that motor. You won't be sorry. If you want a little more, the voodoo 268 cam.

Rubeng442
Jan 16th, 12, 7:26 PM
Take a look at the Comp Cams:

268AH - 268/276 222/226 .464/.464 110 LSA

265DEH - 265/269 211/221 .442/.465 110 LSA

I could be wrong but the 268AH looks to be about right given the restrictions.

Highway Star
Jan 16th, 12, 8:16 PM
Oh man...this is the cam you need, saw it in the catalog the other day. Probably about perfect....IMO...ought to be reeeal nice. A Howards Cams flat tappet oval track lift-limited grind. Looky...

Howards Cams Max Oval #111241-06
Duration at .050" 224°/232°
Lift .450"/.450"
LSA: 106

blumont
Jan 16th, 12, 10:47 PM
Quite a few years back UDHarold sold me a cam for my vortec headed 350. I believe it was 221/221 @.050. Lift was .454/.454, 110 LSA. It was a shelf grind from Ultradyne. That 350 was a great engine.

Ultradyne 276H10

Mikeys69
Jan 16th, 12, 11:09 PM
OK now you have like 12 cams to pick from, now which one. lol

Highway Star
Jan 29th, 12, 4:09 PM
to the top...OP, did we post too many cams? Did you decide?

midnight1961
Jan 29th, 12, 5:04 PM
to the top...OP, did we post too many cams? Did you decide?

I haven't bought the cam yet, but I've about decided to get the stiffer springs and go with this cam:

http://www.summitracing.com/parts/LUN-60102LK/

Mikeys69
Jan 29th, 12, 5:04 PM
to the top...OP, did we post too many cams? Did you decide?

Highway Star. That's a BIG problem here on TC. Everybody has to comment on something different..lol

Tom Mobley
Jan 29th, 12, 6:49 PM
LOL, it's not a problem, it's an opportunity...... ;)

Highway Star
Jan 29th, 12, 8:38 PM
This *is* the internet and there are a lot of knowledgeable guys on this website. ..BBC guys and SBC guys. Sure, the op got a lot of suggestions. He also got that many different people to ask why each cam was suggested . If we all answered, this would be a pretty valuable thread.

I picked the one I did so that stock parts could be used with stock pressures, but still have the duration to make more power and tight LSA for torque and cylinder pressure & effective/dynamic compression with the early ICA. It has a nice split to compensate for the heads also.

Yellomalibu
Jan 29th, 12, 9:59 PM
Somebody help out here... don't the Vortec heads need more than just springs to be able to handle more lift?
I thought there was machine work required, too.

I'd just like to clear this up before the OP buys the cam he has chosen...

Iwanna64
Jan 29th, 12, 10:06 PM
I believe there's a drop in spring kit you can buy that will allow up to .550 lift with no machining.
http://www.carcraft.com/techarticles/vortec_valve_spring_upgrade/index.html

Slick71ss
Jan 30th, 12, 10:26 PM
Somebody help out here... don't the Vortec heads need more than just springs to be able to handle more lift?
I thought there was machine work required, too.

I'd just like to clear this up before the OP buys the cam he has chosen...

I'd like to post a quote from the Nastyz28 forum that talks about or answers your question. This quote and pages of other info on Vortecs is located here... http://www.nastyz28.com/forum/showthread.php?t=56505


Good question, easy answer.

Scoggin-Dickey sells Vortec heads already correctly modified for use with high-lift performance camshafts. They also sell a complete kit which has the modified Vortecs, intake manifold (Edelbrock Vortec), rocker arms, etc to basically bolted on your existing short block.

Sallee Chevrolet has an interesting solution to this problem (from their website):

The Sallee Chevrolet solution is to use Crane Cam’s 10309-1 drop-in valve spring and retainer kit which is good for .550” lift with no machining. The installed height for this Crane Cams kit is taller and the lower part of the retainer is shorter. The “AVERAGE” clearance between the retainer and seal is .575” for this kit. We have found that some of the Vortec heads, coming from the factory, do not have the valve seals driven on all the way. You need to check that they are before installing this kit. If they need to be driven on all the way, we have found that a 3/8” drive - 1/2” socket fits the valve seal just about perfect.As with all modifications to performance engines though, you should always measure to assure that there is proper clearance and fit.

Comp Cams sells a tool that will cut down the size of the Vortec valve guide and is around $50 or so.

Another method is the infamous Vortec retainer "ghetto grind". If the camshaft being used only requires a stock 1.25" diameter single-wound valvespring, it is possible to only need to grind off approximately 3/32" off the bottoms of the stock Vortec retainers with a grinder or on a grinding wheel to achieve enough R-G clearance to run up to approximately .530" -.540" safely. I must caution here that R-G clearance must ALWAYS be checked to verify that there is in fact enough clearance - also include allowing for coil bind. One other thing - you must remove the dampner in this modification. Don't worry -- the stock Vortec valveguide being much larger in diameter than other SB heads will act as sort of a dampner and I never noticed any RPM issues related to lack of running one when I did this mod. Although myself and others who have done it this way have had no problems, I must caution this basically for those on a strict budget and cutting down the guides either with the Comp tool or at a machine shop is the best way to go. However, I'm of the opinion that since it works well within the noted constraints, then you're really only out your time to grind down the retainers. The choice is yours.

Bullcrappy
Jan 30th, 12, 10:50 PM
they can handle .480 and a lil more with this...

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&vxp=mtr&item=310375341636

Bullcrappy
Jan 30th, 12, 10:51 PM
or

http://www.jegs.com/i/Crane+Cams/271/10309-1/10002/-1

wade w
Jan 31st, 12, 8:25 PM
I'm on my phone so I can't post a link right now, but there was a story in car craft I think. They gave part numbers and every thing and I have done it. They used beehive springs. No machine work needed. Its not cheap, but you can get somewere around 550 lift. I used them so I could use a hydro roller. If you do a search on vortec head valve spring upgrade. It will come up.

BowtieAaron
Jan 31st, 12, 9:23 PM
This is what happens when you use beehives

http://i28.photobucket.com/albums/c209/ssclonelq9/Moyer%20Speed/65868abf.jpg

http://i28.photobucket.com/albums/c209/ssclonelq9/Moyer%20Speed/85d8d46b.jpg

http://i28.photobucket.com/albums/c209/ssclonelq9/Moyer%20Speed/730ee525.jpg

http://i28.photobucket.com/albums/c209/ssclonelq9/Moyer%20Speed/d55eed90.jpg

This is on a 99 ls1 corvette that I'm working on. It had a mid 220's cam and ported heads it made 398rwhp.
I've never liked single beehives and this just proves me why.

You can buy 1.29" dia springs with Ti retainers in good rates for decent price. Don't skimp on springs to save a few bucks or you could be out a few grand

Bullcrappy
Jan 31st, 12, 11:16 PM
i posted links above.

I'm on my phone so I can't post a link right now, but there was a story in car craft I think. They gave part numbers and every thing and I have done it. They used beehive springs. No machine work needed. Its not cheap, but you can get somewere around 550 lift. I used them so I could use a hydro roller. If you do a search on vortec head valve spring upgrade. It will come up.

wade w
Feb 1st, 12, 6:40 AM
This is what happens when you use beehives
I've never liked single beehives and this just proves me why.

You can buy 1.29" dia springs with Ti retainers in good rates for decent price. Don't skimp on springs to save a few bucks or you could be out a few grand

Ls1's come frome the factory with them. So your not going to make me believe there all bad because ONE failed. Things break.

Yellomalibu
Feb 1st, 12, 7:05 AM
I really don't want to have anything done to the heads. Just looking for something that matches up good with what I have. This car is just a cruiser, but low end torque is what I'm looking for.

The first page or two offered several options for the O/P to choose from. I wonder; has a decision been made?

BowtieAaron
Feb 1st, 12, 8:07 AM
Ls1's come frome the factory with them. So your not going to make me believe there all bad because ONE failed. Things break.

Ever see their stock lobes and cam specs?
Do a google search for comp 918 spring.
This is my 4th ls1 I've seen with a sub 224 @50 under 600 lift cam bust a beehive.

There are plenty of guys on here who have busted beehives and single springs as well..

cstraub
Feb 1st, 12, 8:31 AM
I have made a MACHINED 7 degree +.050" lock for many years. This will gain you .050" of install height with a simple lock change but it will reduce your seat pressure. I have a spring that will solve the loss of pressure also.

novadude
Feb 1st, 12, 8:41 AM
I have a spring that will solve the loss of pressure also.

Chris... are you talking about a "drop in" for unmodified Vortec heads? Can you share more details?

cstraub
Feb 1st, 12, 9:06 AM
It would be an 1.260" OD spring made from the Super Clean material. This is what the high end springs are wound from. The supplier is Japanese company in Kobe, Japan. This spring along with my +.050" MACHINED locks will give any Vortech head .050" more clearance between the guide and the bottom of the retainer. The spring pressure would be 130# @ 1.750" or 115# @ 1.800". I also for an upgrade have a retainer that will work and is shorter than the OEM retainer giving more clearance.

Also note the locks I have are machined. Not stamped. These are precision machined pieces.

novadude
Feb 1st, 12, 9:10 AM
What is the spring rate? I'm just looking for a spring that will work with mild FT lobes (Isky Megacam - 0.465" lift). I don't think I need a lot of spring, and don't want a lot over nose load, but I think I'll need something better than the 80# stock springs.

Will these typically set-up at 1.800" in a stock vortec head w/ +0.050 locks?

Doug Garland
Feb 1st, 12, 7:48 PM
Back to the original question. Did you decide? I am building a similar engine to yours, and I got my engine builder to use a L-79 update cam. It has a little more duration @ .050, and a little more lift, around .450/.460 lift, but has an updated more modern ramp design.

Slick71ss
Feb 1st, 12, 8:16 PM
Sounded like his mind was made up to me. :confused:

I haven't bought the cam yet, but I've about decided to get the stiffer springs and go with this cam:

http://www.summitracing.com/parts/LUN-60102LK/

cstraub
Feb 1st, 12, 9:32 PM
What is the spring rate? I'm just looking for a spring that will work with mild FT lobes (Isky Megacam - 0.465" lift). I don't think I need a lot of spring, and don't want a lot over nose load, but I think I'll need something better than the 80# stock springs.

Will these typically set-up at 1.800" in a stock vortec head w/ +0.050 locks?

Rate is around 320# per inch. They should set up around 1.800"

Yellomalibu
Feb 2nd, 12, 6:04 AM
I have made a MACHINED 7 degree +.050" lock for many years. This will gain you .050" of install height with a simple lock change but it will reduce your seat pressure. I have a spring that will solve the loss of pressure also.

Sounds like a good DIY way to get a much larger variety of camshaft choices for stock vortec heads. What is your price on this "kit" ?