Is a new cam worth it?

[muddpile]

I've been thinking lately about my restoration, and figured maybe I could add a little bit of juice to the engine in terms of a new cam. I've never done a cam swap in my life, but I figured since the hood, fenders, grille, rad/support, etc. are all off, along with the intake and valve covers, I might as well think about upgrading. The engine is an early 80's suburban 350 with HEI, perimeter bolt valve covers, and it will soon have an edelbrock 600CFM carb and performer intake. I've heard lots of good about Lunati Voodoo cams and lots of bad about edelbrock performers, but that's about it. The truck is a 72 LWB with a 350, TH350 tranny and highway gears out back (not sure of the ratio). The truck is going to be a driver, so I want to retain as much fuel economy as possible, but still get the most power out of it that I can (if at all possible). Is a cam swap something I can do myself with basic tools, and can anyone reccommend a good one for me?

[bskylerj]

How old is the rest of the motor? A cam is always a niuce upgrade. PM Twotons, he is a member here now and does a lot of performance upgrades. He he can help you with this question

[VetteVet]

Here is a little information on cam installation.http://www.amotion.com/tech/caminst.html

And here is an article on which cam to choose
http://hotrod.com/techarticles/113_0209_cam/

[cdowns]

alot of times putting a cam into a himilage 20year old motor just leads to an earlier funeral for that motor// the extra stress put on the valve springs that have already been thru millions of compressions then they break drop valves destroying pistons and cylinder walls ETC

[special-K]

I agree with cdowns,I don`t modify engine dynamics with any significant miles on it.

[Billla]

Originally Posted by special-K

I agree with cdowns,I don`t modify engine dynamics with any significant miles on it.

I've done a lot of cam swaps on engines after 30K miles - I did one on my Impala SS at 96K miles

I agree in general that if there's something weak or breaking a new cam is going to find it, and something radical is NOT a good idea unless you're upgrading everything else. But a reasonable upgrade is a Good Thing and will pay back with decent HP improvement. The important thing is to match the cam choice to your driving and the rest of the components - putting in a radical cam with a low-rise iron manifold and Q-jet isn't going to get you anything. As cdowns noted, you need to be ESPECIALLY concerned with the geometry and springs - stock springs + radical cam = broken parts.

Make sure the cam you select is suitable for stock springs and rockers and you're good to go.

There are a lot of articles out there on the swap, but the only two things I would add is to degree the cam - it doesn't take long and ensures everything is in the right place, and be sure to use a really good break-in lube...I use the MFGR's lube and then GM EOS in the oil during break-in and haven't wiped a lobe yet.

Good luck and tell us how it goes!

[muddpile]

The motor was swapped in by the previous owner, so I have no idea how many miles are on it, if its been rebuilt, etc. All I was told was 80's suburban. Maybe a swap isn't such a good idea with this level of uncertainty.....

[special-K]

Originally Posted by Billla

I've done a lot of cam swaps on engines after 30K miles - I did one on my Impala SS at 96K miles

30K ain`t bad,do what you want.I do.

[Chevrolet4x4s]

I would suggest going with the Performer EPS (as it is specially tuned to Edelbrock carbs manafold) as opposed to the Performer.The EPS realy wakes up a sbc over the stock intake
Hope this helps
Shane

[1970 CST Short Wide]

Just DONT buy a Comp Cam, They are junk in my Opinion

[phantom dually]

Originally Posted by 1970 CST Short Wide

Just DONT buy a Comp Cam, They are junk in my Opinion

Thats a pretty BOLD statement!! Comp is the biggest name in cams. Did you have a bad experience??

[davidh]

Originally Posted by phantom dually

Thats a pretty BOLD statement!! Comp is the biggest name in cams. Did you have a bad experience??

It seems I've heard people say their cams were "soft" before. Once I put one in a motor that was used or been used about 10K on it. I like 268 comp cam for daily drivers. For a uncertain used engine I'd stick with house brand $80 cam and lifters instead of $160 comp cam

[davidh]

I'd put in a cam with no more than 450 lift in it. since it's an older engine try one of the summit cam kits for $80 bucks. think the part no 1103 or something would be good. I had a motor down to what you are saying and I just couldn't resist and added a cam. 262XEcomp cam.

[Billla]

Originally Posted by davidh

I'd put in a cam with no more than 450 lift in it.

This is pretty good advice overall - .450 lift is a perfect number IMHO and shouldn't bind with stock springs and 1.5 rockers.

[muddpile]

So .450 lift is kind of the magic number for a stock/semi-stock application? And all I will need to upgrade is the cam and lifters correct? Not pushrods, rockers, springs etc? Also, what are some brands to look for/stay away from? Like I said, this is a driver, so I want a nice compromise of power/mileage/driveability.

[Billla]

Originally Posted by muddpile

So .450 lift is kind of the magic number for a stock/semi-stock application? And all I will need to upgrade is the cam and lifters correct? Not pushrods, rockers, springs etc? Also, what are some brands to look for/stay away from? Like I said, this is a driver, so I want a nice compromise of power/mileage/driveability.

Not a magic number, but in the right range - certainly nothing more.

You can't take ANYTHING for granted with valvetrain geometry. Check all the pushrods for straightness and ensure that you're not getting coil bind or rockers interfering with the studs. You still need to check everything, but the expectation is that everything should fit.

I'm a Crane guy myself, but you'll need to wait for the flood of opinions

[truckdude239]

Originally Posted by muddpile

So .450 lift is kind of the magic number for a stock/semi-stock application? And all I will need to upgrade is the cam and lifters correct? Not pushrods, rockers, springs etc? Also, what are some brands to look for/stay away from? Like I said, this is a driver, so I want a nice compromise of power/mileage/driveability.

yup just remenber new lifters or you will wear that cam out in about 3 mins with old lifters

[Bob D]

Originally Posted by davidh

I'd put in a cam with no more than 450 lift in it. since it's an older engine try one of the summit cam kits for $80 bucks. think the part no 1103 or something would be good. I had a motor down to what you are saying and I just couldn't resist and added a cam. 262XEcomp cam.

I was forced into the same cam replacement situation a year ago when one of my lifters blew apart. The guts came out of it right past the retaining clips So the job snowballed from there and I ended up discovering that the cam itself was badly worn and had a chipped lobe, some of the pushrods didnt match and one of the rocker studs had pulled out of the head. The engine turned out to be a 1970's block, '79-'85 heads. The block had been shaved and bored 30 over. I ended up installing the Summit 1102 cam/lifter kit, Summit pushrods,Edelbrock timing chain&gears and Headman Hedders. I already had the performer intake and 600cfm carb. The performance difference was night and day! Runs like a bat out of hell off the line but gets a little scarry at about 70 mph with the 3.73 rear end.

Gas mileage stayed the same 9 mpg average


Bob

[muddpile]

So one of those cheap summit cam/lifter kits would work fine for my application? I may have to order one up.

[twotons]

at .450 lift you may want to go with a set of long slot rockers, abou 60 bucks with nuts and pivots. i have broken some of the short slots at that lift, if it is a mild engine you might want to stick with 215 to 225 @ .050 duration, or it will be a tottal pig. I think Elgin makes a 218 224 @ .050 and 440 ish lift cam that works really well.

hope this helps.

[bg67lwb]

My experience with SBC engines is that the cams and lifters do not seem to last as long as the rest of the engine. I would replace with a stocker, at least. Talk to the parts guy at your local Goodwrench dealer. Find out what seems to be the best option for your block based on how you are going to use the vehicle.

[rkarr]

Originally Posted by bg67lwb

My experience with SBC engines is that the cams and lifters do not seem to last as long as the rest of the engine. I would replace with a stocker, at least. Talk to the parts guy at your local Goodwrench dealer. Find out what seems to be the best option for your block based on how you are going to use the vehicle.

I agree.. If it were me, I'd be VERY simple about it and get something like an old STOCK grind for a corvette... I'd be nervous about the lift, duration, and possible coil spring stress with anything else... if you're gonna go all the way, I'd stick with matched components... Edelbrock makes an intake and cam that works well "together"...
I don't know about you, but I'd rather be driving my truck than wrenching on it... Whatever you decide to do, take your time and think about what you want, then do it.

[davidh]

come on everybodys doing it. Can't you feel the peer pressure? Just kidding. Think of it this way. Add the cam for this motor and you may want more or less cam on the "built engine" you drop in later. Dont do a stock cam.. The 1102 or 1103 cam would be good. Put a curve kit in the distributor too. To me the cam is one of the easiest ways to make a small block come alive. Just don't submit yourself to the "mores law" if a little is good a whole lot is great. Not in cams.

[jbon64]

i had a performer cam & intake combo on a 350 , it ran great , got decent mileage and the cam had just the right lope to it ......sounded great

[special-K]

Whatever you do about your cam replacement will be temporary until you can do an overhaul or rebuild.As said before,(which is what I was gettin`at) the top-ends go before the bottoms.These days w/ no-lead fuel,the seats/guides/seals end up needing the once over and most experts will agree you`re just pissin`into the wind w/o going farther.If it`s going to take you 10 years to put 10,000 miles on it,or you`re going to sell it off,then go cheap.SBC cams seem soft,if anything.They are known for early demise,putting you in the situation you find yourself in now.Do what you want.Me,I'd just keep it going w/o throwing much money at it until a fresh motor can find it`s way under your hood.
Question:Are Competion Cams soft,or does someone not know how to properly set up/adjust/match a valvetrain?