Hey everyone, need some help here picking a good cam for my car. Its a 350 roller block with factory vortec heads, dual plane intake, holley 650 carb, headers and straight pipes. I want to slide a better cam and lifters into it but I don't want to break the bank with engine mods. What would be the easiest install and best cam/lifter combo for this? Looking for good driveability and low to mid range power while keeping fuel economy in mind. Not asking much huh?

 

Used zz4 cam and ls7 lifters

If you had budget for a new cam, i would do something like the howards
https://www.summitracing.com/parts/hrs-181145-10

Or any similar size brand

 

LT4 Hotcam (Installed 2* advanced from the 109 ICL
LS7 Lifters
LS6 Valve springs
Comp 787 retainers
1.6:1 self aligning rockers

Properly tuned its good for about 400 HP and 430 TQ.

Run about a 2,400-2,800 rpm stall speed torque converter and it will SCREAM.

Had that setup in an Express van I tow with. LOTS of HP and TQ.

 

Have the Vortecs been modified for lift beyond ~ .460"?
That's about your limit with the stock heads.
Any cam with a performance orientated grind will need springs better than the OEM version as well.
As an example, my first go around with Vortecs was with a flat tappet .454", 218 @ .050" single pattern cam. Vortecs were new out of the box with no modifications. The engine felt healthy enough however one burnout too many put a valve into a piston and that was that. The solution was the addition of Comps 26918 spring and retainer (with .050" taller offset locks). That allowed for jump in cam specs to an XR276HR. 224/230 @ .050", .502"/.510". No machining was required to allow for the increased lift however I did cut the guides for a positive style seal. The heads were also adapted for screw-in studs. That put the 3700 lb car into the 12's. I also knocked down over 20 MPG on the highway.
You've got factory rollers lifters so you should be good to go there.

How's Marathon doing? I've passed through there many times travelling to and from the west. Ever see a grey 86 Coupe pass through?

 

Looking for good driveability and low to mid range power while keeping fuel economy in mind.

Pick 2 and forget mid range power!

 

All good options/comments above except that last one. With the mild cams suggested, you can have all three All it takes is some attention to tuning.
The biggest factor in your cam choice that you haven't specified, already alluded to by Fast, is TC stall. Are you after just good road performance? or dragstrip times?

 

So what's your recommendation then? Or are you waiting to criticize another's? Thx for showing up. I can tell you are a big help even with out any cam to recommend.

 

So given the fact that my heads aren't modified in any way, what are my options for putting a bigger cam into this? Don't really want to start pulling heads and sending away for machining. Looking for something easily installed.

 

looking for good seat of the pants road performance. Not worried about times .

 

haha not many people know this area. We're all still hiding in our igloos from the cold lol

 

For seat of the pants, good low/midrange power output, hard to beat those two options Orr99 suggested. I run the same ZZ3/ZZ4 cam (see sig).
The LT4 Hotcam will give you a more rumpity idle, but definitely requires a higher stall converter as was mentioned to make up for it's weaker low end (mild long-ramp lobes bleed off more cylinder pressure at low revs, reducing torque; however, that characteristic makes it pull harder at the higher revs. As FAst said, it definitely works better installed at a 106-107 ICL rather than the "drop-in" 109 ICL.

 

Alex Spring Kit. LT4 Hotcam or ZZ4 Cam. You will have a strong runner. I like 86 LG4's setup as well as skinny z's setup it is very impressive for the power and gas mileage he gets.

 

oh yeah....gas mileage!
Forgot to mention, with the E4ME factory carb, I've squeaked out 26 mpg with the ZZ4 cam.

 

Any of the above posts are steering you in the right direction.
Now there are a couple of questions you have to ask yourself: (as pertaining to box stock Vortecs)
Cam only and no additional parts which would include springs, retainers, locks, etc? This limits valve lift to ~.460".
Cam and spring upgrade? There are several options here. I'm partial to to Comp's 26918 spring only because I've had success with them in several builds. Other's have had luck with Alex's springs. Any of these would raise the lift limit to about.540". No machining required for either approach.
Once you enter into new spring territory, you'll need to address the pressed in rocker studs. Pinned (maybe), screw-in (preferred).
The OEM roller lifter arguably had a 6000 RPM limit. Beyond that the lifter body would distort and bleed off hydraulic pressure. With some of the cam choices presented here, you're entering into where power production above 6000 RPM becomes relevant. An aftermarket or LS7 lifter might be required. (As a side note, the problems with the lifters was often associated with loss of valvetrain stability due to inadequate springs. Further testing has demonstrated the weakness to be the lifter, although the spring always has to be considered as well).
Let's not overlook valve train geometry as that has to be addressed with the change in cam (and probably when the Vortec heads were added but probably wasn't considered). That may mean a change in pushrod length.
You can see how it all adds up.
Perhaps, as I did the first time around, you'll consider a cam that requires little if anything in terms of installation. I've found that a difficult prospect when the roller cam almost always allows increased lift values vs duration. It's the lift that hurts here. Perhaps someone has a recommendation for a small lift cam. Back then, my experience was with a flat tappet cam profile. .454" w/218 @ .050" much like the tried and true (and outdated ) Comp 268H. (Flat tappet unfortunately).

As for Marathon. I've passed through there many times in the past 35 years travelling to and from the west. Always going someplace else but needing fuel along the way.
I thought at one time Marathon was part of the airport turned dragstrip group that exists in northern Ontario. I did a quick on-line search but the closest I could come up with was Terrace Bay. Maybe Dryden...?

 

ya thats terrace bay. Marathon almost got a strip but it never amounted to anything. Still don't know which direction I'm going to take with the car. Machining parts means shipping them 4 hrs away and a big pain in the ***. I wana be able to toss a cam in and maybe some new lifters and rockers and that's it. UltimatelyI'd like to turn as much hpas I could but budget says otherwise lol

 

Yeah you could try a beehive 26918 kit which should get you extra lift or the Alex parts spring kit which several have used here with success. A cam around .500-.520" lift should run under those but you should measure/ check

 

I've been looking for a .450" lift rule (oval track) cam but can't find anything that's a hydraulic roller. Finding that would be the ticket for the Vortec limited lift. Now, that said, any cam that would fit that category would probably specific an upgraded spring.
So, I think, that's where you're at.
Cam, springs with retainers, offset locks (and I specify that because the Vortec uses a 1.7" installed height spring and any of the aftermarket springs suggested here have a 1.8" installed height. The .050" offset locks are required to bring the spring heights in line with the spec). Keep the lift around .520" (+/-) and depending on your compression ratio, you should be able to dial in a pretty decent combination. Speaking of which, do you have the engine specs (piston dish and height below deck, head gasket thickness in particular) or the actual static compression ratio numbers? That'll be the deciding factor in the overall cam selection.

 

Stock unmodified Vortec heads can only handle something like 0.480"lift cams. That should limit your cam search quite a bit. But I read several owners are using stepped spring retainers (from Comp Cams) to allow greater lift but you would need to verify this for your self.
If you want good mid-range with good fuel mileage your looking at short duration camshafts with tight lobe center line angles. SBC stock heads like a 108 LSA but a better breathing Vortec head could run well with a 110 LSA. For duration you need something less than 265* full duration and more likely less than 260*. This short duration compensates for the increased overlap of a tight LSA. This will have power band below 5,500 RPM but a better solution than a larger cam that your heads can't use the higher lift and your torque converter doesn't match.

I guess what I'm saying is larger cams need better heads and higher stall converters - more compression too. A shorter cam would be a better match for your goals.

Good luck.

 

ya that's one thing I don't have yet. I'm going to have to get in the garage sooner or later and get it tore down I suppose and do some measuring. Was hoping it would be a drop in cam but learning with this engine combo there's guna be more to it lol

 

Comp cam has magnum low lift lobes, and the tri power extreme lobes

You can get around .450 lift or .480 lift anywhere from 206 deg to 250 deg with the magnum low lift.

Tri power is for baby cams up to 218 deg at .050. .480 lift or .450 lift options

Fairly soft lobe families tho.


Xtreme 4x4 are very aggressive but up to .474 lift. Beehive kit, this likely will fit in the vortec head

Anything else classified as lift rule lobes would be way to aggressive for street life

 

Totally overlooked the Magnum line up. Maybe there's a low lift roller in there that'll allow the stock springs. As I mentioned, I had done it with a flat tappet cam similar to the old Comp 268H. Compression ratio was right around 10:1 and cranking pressure was north of 200 psi. Not a power house but very responsive and excellent highway fuel economy for a carbed application and limited hardware to tune on.
It loved the TH700 first gear and 3.70 rear gear. Boiling the tires was not an issue.

 

Eh i'd replace springs regardless even if it is a stock lift profile. Stock springs are abit weak

I only used magnum high lift lobes with great success

 

You can grab a set of LS6 springs for about $70 and a set of comp cams 7* retainers and that should get you good to about .520 lift (I read many places this gets you to .550 total clearance, so .520 with .30 margin). Both are avail on Summit/jegs.

 

With the valve seals tapped all the way down the last 5-6 sets of Vortecs I have actually bothered to measure had ATLEAST 0.520" clearance giving them room for .490" lift in stock form with 0.030" left to spare. The Comp 787 retainers with the LS6 springs allow you to offset that by +0.050". That means you clear 0.540" with 0.030" left to spare. I have run one set with 0.554" on both sides without issue.

 

Yeah I did read that in a bunch of places too, that just replacing the seals or tapping the stock ones down would really help. I did a lot of research on the vortec heads because I was super close about a week ago to pulling the trigger on all the parts for an l31 swap with an lt4 hot cam. But I think I might Focus this season on appearance and maybe some suspension upgrades, it runs great and I'm not racing with it. It's fun to drive even with pretty much stock 305.

 

.

 

Not too far off the often quoted .460-.480".
Seeing as a spring upgrade is required for anything other than the tamest of replacements, pending a review of the current compression ratio, the OP has plenty of choice regarding a cam.
Considering also that replacing a cam with the engine in the car (as I believe that was the original intent) makes the valve spring swap minor in comparison.

 

You DON'T want a Magnum cam, or ANY OTHER single-pattern, w Vortec heads.

THIMK... the ONE THING that makes those heads better than any others before them, is their INCREASED INTAKE PORT FLOW, accomplished by moving the port about ½" upwards to give a straighter shot into the cyl. BUTT... they have the same sucky exh ports as any other SBC head. Well, you can't make more power unless you generate more heat in the cyl during combustion; and the easiest way to do that, is to put more air and fuel INTO the cyl; but you can't do that unless you can get the old spent stuff OUT from the last time that cyl fired. For that, you need an exh lobe with LOTS more duration than the intake, but not necessarily more lift, since exh flow doesn't keep increasing as lift gets larger. The valve is smaller, and the port is smaller, meaning that the distance that the valve opens, IS NOT the bottleneck, and therefore flow DOES NOT increase by increasing the lift past some certain point.

The LS7 lifters, LS6 springs, Comp 787 retainers, and a cam with less than around .525 lift, will drop RIGHT INTO your motor. Best all-around recipe for simple cheeeeeeep plentiful non-exotic stuff these days.

I'd look at "custom" grinds. Specifically, I'd try to find someone to grind an intake with about 275° of "advertised" intake duration, about 225° .050", and about .510" lift; and on the exh, about 285° advertised, 237° .050", and about .500". I'd have it ground on 110° lobe centers and install it at about 106° ATDC. You'll want about a 3000 - 3200 RPM stall with that. Better valves will also help, such as Manley "Street Flow", esp on the exh; but I think when you see how much better REAL valves are than stock, you won't want to leave stock ones on the int either, even though they won't make as much difference there as they will on the exh.

 

I tend to agree but wouldnt rule out single patterns tho. David Vizards vortec headed budget build used engine quest replacement vortecs and a 224/224 108 center. 447 hp
http://www.hotrod.com/articles/0611e...all-block/amp/

But i would tend to run a split pattern on any head to carry power up top

Custom grind is always prefered but does add cost, depending on the core used. Comp atleast does basic grinds for same price as shelf. The billet cores are 409$

 

If you want a drop in cam only you could install the same cam I'm using in my fourth gen. It's a hydraulic roller used in the Ramjet 350 and the GM 383 crate motor. Part #14097395. It burns rubber all day and my Camaro has 18.5" Hg vac. Can't get the car to hook so strip times are the same but that will change with rear axle re-locators. Still get 20mph.

Check it out.

 

Look into Herbert cams. We have run them for decades. They have some nice grinds and can build what can you need.

 

Check Bullet also. Their whole lobe catalog is online. Including a bunch of Harold Brookshire's Ultradyne designs, which Bullet bought when Ultradyne imploded.

The RamJet cam is sub-200° of .050" duration. Great torque (aka boil the tires off) but that's about it. Limited high-RPM performance at best.

Physics says, Vortec heads need a split-pattern cam. Keeping in mind that the article quoted above WAS NOT Vortec heads; it was aftermarket heads with the Vortec port pattern. 2 potentially VERY DIFFERENT things.

Fizyx yz phun.

Yes I was a math & physics major my first run through college.

 

Over and above the exhaust flow, the exhaust system probably gives the greatest cred to a split pattern cam profile. All the more reason to make sure that from the headers through to the tailpipes, it's desinged properly. If you can get past that, even with the "sucky" exhaust port, then the single pattern is better suited if you are building for torque. And, as a bonus, better mileage. That's taking into consideration where in the exhaust profile the additional duration is being added. (Typically about 2/3rds to the opening side of the ramp.)

That's a hell of a split. And a wide LSA for the head and cubic inch.
Comps XR276HR is what I've used in the past and has about half the split with 276/282, 224/230, .502/.510, 110/106. Overlap 59°.
Considering that engine (with OEM Vortecs) made peak power at about 5700, but essentially flat from test RPM start about 3500, sort of indicated the there was more to it in terms of peak HP (which was modest compared to other Vortec builds). My problem was the really shitty exhaust and I figured the split would help. Same as suggested here.
Given that information, if I could have addressed the exhaust system flow (after the port), I would have:
Kept the same overlap: HP peak was in the right spot.
Tighten up the LSA to 108°. There's too much data to deny that the typical Gen 1 SBC headed 350 doesn't produce the best numbers with that 108° LSA. That would include the Vortec.
That gets a adv duration of 275 equally split. ~224 @ .050".
Looks alot like the post below.
My guess is that this engine (and the OP's) could produce similar results.
Despite the Vortecs exhaust port but having addressed the exhaust system.

It seems that the dual pattern profile does suit higher RPM applications.
The industry standard it seems, is to put most of the additional exhaust duration to the opening side of the ramp. This allows more time for the cylinder to blow down. It also has the effect of hurting low RPM torque. And mileage.

 

Oh did I mention the Ramjet cam is cheap? No other parts needed for the swap other than gaskets.

 

I dont necessarily buy into the exhaust intake flow ratios for determining duration split

It really depends on what you want the engine to do. Most race motors do have good intake to exhaust flow but they will run 8-12 deg exhaust splits. It usually makes power carry beyond peak hp

lsx stuff has great exhaust intake flow but work exceptionally well with alot of split.
Hell even turbo cars are getting away from single patterns

 

For all intents and purposes, I've confined my dialogue to the Gen 1 SBC 23° head w/ an average 10:1 CR.
It's the massive amount of information available that allows some certainty when saying something like the 108 LSA for 350 CID is about the optimum.
Once you get outside the Gen 1 23° envelope, the results change. The discharge coefficient with respect to most early SBC is about the same. This is all before the port has a major influence on flow and you're talking about .100" - .200" valve lift here. It's about the valve size and the valve seat efficiency. Jump to an LS and the head development shows through and the performance achieved with a tight LSA in a Gen 1 isn't needed to produce the same "results" in a Gen III/IV. So a wider LSA can be used and gets the advantages that it provides as icing on the cake. Typically a broader and flatter torque curve. Somewhat the same deal with a BBC. Even with the same CID, the better flowing heads of the BBC allow for a wider LSA.
Boosted applications are another story altogether and I will excuse myself from that discussion as I've little to no experience.

 

Yeah, and if they had it at Wally World or Harbor Freight, that'd be an equally strong recommendation.

Build once, enjoy many. "Cheeeeeeeeeep" disappears into the background noise after about your 1st half-mile on your new motor. DON'T make bad decisions based on that. Which is NOT the same as saying, "spend lots of money"; rather, it's saying, spend money where it MATTERS, and NOT where it doesn't. And the cam MATTERS.

 

I disagree! I ran the Ramjet cam for a while and honestly it is no better than the Vortec cam in terms of HP. Makes more torque but the HP honestly SUCKS.

I used 1.6 rockers with that cam and had valve float happening as early as 4,500 rpm. Changing the springs to LS6 springs and Comp 787 retainers raised my RPM for peak HP by 300 from 4,400 to 4,700 and gave me a solid 40 hp gain at the 5,600 rpm fuel shut-off. That being said the Ramjet cam was designed for a 350 with TPI heads in a boat and is designed to completely die over 5,200 rpm to keep from over-reving while pushing a boat down the lake. Not exactly what I would want in a performance oriented car. The plain jane F/Y-car LT1 roller cam runs so much better, has a smoother idle and makes more vacuum and has a flatter torque curve. The LT1 F-car cam is a drop-in and gives a solid 20-30 HP gain over the Ramjet. I fought detonation in hot weather with both the 395' Ramjet cam and the Vortec factory cam. The hotter LT1 cam cuts the dynamic compression ratio just enough you can run full advance on pump gas and actually made more torque with less compression.

 

All the gm cams can be had for cheap used. Zz4, the gm 222/230 crane cam, lt4 hot cam, etc

Then the lt1 type cams...can find from time to time. Cc502-503, crane 227, etc

 

Totally agree.The ramjet cam is a good 4x4 truck cam at best.Not an f-car cam.

 

The Vortec truck cam is another sub-200° @ .050" grocery-cart-ish wonder. Might be appropriate for hauling loads of asphalt or pulling around a trailer of lawn mowers, but bears no relationship whatsoever to anything "performance". It is NOT a "performance" oriented piece in ANY manner way shape form or fashion. Doesn't belong in this discussion, any more than the RamJet cam does.

 

Could not agree more. Its really not even a good 4x4 cam because I would want a torque curve that is flatter than the Ramjets. Works well in a boat though.

I have software to tune the marine ECMs and I can say first hand that swapping out the factory Ramjet 350 cam for a LT4 Hotcam with nothing more than a LS6/Comp787 upgrade on the springs/retainers and a retune was worth 75 HP at fuel kill. Peak HP increased by 55 and moved from 5,100 rpm to 5,600 rpm. Running 1 3/4" long tube headers, flowmaster cone reducers, dual 2.5" exhaust, and magnaflow mufflers, the Ramjet 350 made right at 365 HP with the stock cam, with the LT4 Hotcam 3* advanced, made 420 HP. From the lowest RPM the dyno could accurately load the engine (about 2,700 rpm) the LT4 Hotcam made more torque. Not to mention the LT4 Hotcam sounds like it belongs in a hot rod

 

I think your missing my point. It's not only cheap but it should bolt in w/o any other parts other than gaskets. And it doesn't need a torque converter or any gear change. I can't explain why others would run the cam into valve float territory when it's really a 5,500rpm and below only cam .

Like I said before you want fuel mileage, low parts cost and mid range torque? Choose 2 and forget about midrange torque. But the Ramjet 350 cam burn up my tires right off idle with 3.23 rear gears and gets 20 mpg. Paid like $220 brand new plus gaskets and anti freeze. No springs, retainers, locators, keepers or lifters.

I can't help but recall all those that don't really even know how to adjust their lifters but spend over $1000 on a new cam and parts. We all have to start and learn somewhere but common sense would be to spend less while doing so. The choice is eaches own.

 

What are the Ramjet cam specs? An internet search has numerous and conflicting results. Some from this forum...

In all of this, (and the OP has all but disappeared), it could be said any hydraulic roller with lift ~.480" and overlap/LSA/duration to suit the RPM/CR could be used. Further to that, if the specs are tame enough, and by that I mean something along the lines of the old Comp 268H (.454, 218@.050"), that the stock valvetrain could be reused. Revs held to 5500-5700 as peak HP would likely be about that.
It worked for me although that cam was flat tappet.
This, I think was the intent of the original post.

 

Marine cam is 196/206@ .050, .431/.451" lift, 109* LSA, 106* ICL. In thr Ramjet it is run with 1.6 rockers.

 

Stock 049 TPI cam or LT1 cam would be a better cheap alternative right? What do you think Fast355?

 

Been sitting here reading a lot of useful info and a lot of different recommendations but in the end all I want to do for now is be able to slide a roller cam into it and maybe springs at most. Hoping for a little bit of lump at idle but not an asset.

 

I need to add the Ramjet 350 crate motor is rated at 345hp and 396ft-lbs torque. You usually need tolower your shift points to optimize that cam rather than increase them.

 

I find it interesting that some have an issue with valve train control with a small cam like the Ramjet whereas in my case, the first experiment with stock Vortecs and Comps 268H (similar Clevite grind) didn't produce any such trouble. It wasn't until a burnout gone wild and the RPMs spiked to somewhere well north of 6000 was there any damage. And the damage was enough to bend a valve (possibly two but it's been a long time).
Thinking about it as I type, perhaps it's the heavy roller lifter that's the difference. The 268H was a flat tappet. More than likely that's the issue. I'm not to argue with any results posted here.
That said, a valve spring upgrade is a small price to pay considering the amount of work to swap a cam with the engine in the car. That's a job I dislike a great deal.

In that case, from what's been posted here, you have a few options.
Go for the LS6 springs or Comp 26918. Springs are pretty much a given with a hydraulic roller.
The best cam will be matched to your compression ratio. As for gearing and such, that can always be changed.
Lump at idle...I was always complimented on the sound of the XR276HR. It worked well with a 9.5 - 10:1 CR. Had a decent sounding idle, pulled about 12" of vacuum (with about 16° base timing), good mid-range and made power up to 6000. I also knocked down some pretty good highway mileage numbers with well over 20 (Imp) MPG on a cross country (through Marathon) trip. With a carb. I also pushed a nearly 3800 lb street chassis into the 12's.
Of course there are other options. I'm just throwing out what worked for me.
It might be worth adding that for my next performance orientated build, seeing as I've pretty much scoured the internet for advice, opinions and the like, I'll solicit the services of one of the more reputable cam profilers. Terry Walters Racing Engines uses David Vizard's COS Cam program to select a cam based on the available engine/chassis package information. Another that comes highly recommended is Mike Jones. Interestingly what they have to offer tends to differ from what is generally accepted as the norm from an internet data base. Case in point being the suggested LSA for a 350 Gen 1 SBC.

 

Might have some influence but i’m just gonna lean towards valvespring condition. Generally weight on the lifter side of things does not matter. Valve side is the prime area of concern. I would be surprised to have float under 5500 with ram jet cam if your springs are atleast stock like in pressures, but they do wear over 100k miles lol

On a stock l98 cam with 1.6 rockers on motor alone, i could rev to 5500 and did not lose control. Same cam and springs basically in my 305 car plus 9 psi boost, it lost control by 4000-4200 rpm lol go figure.