questions about roller cams

[crazy4offroad]

If you put a new cam in you should use it but for an every oil change situation I would say no you shouldn't need it.

 

[bucket]

I still think that for what you want, a roller cam is a good idea. More power and efficiency... stock 70's and 80's cams suck.

 

[Gramps]

I still think that for what you want, a roller cam is a good idea. More power and efficiency... stock 70's and 80's cams suck.

I'm listening, but kind of weighing my options at the moment, just kind of taking in what everyone is saying.

I'm kind of thinking at this point that maybe what I should do it buy a crate motor, and build it up, and just have it on standby, from the records I have on the engine I have now, it was pretty much religiously taken care of, I've been looking through a few pages of maintenance reports, and this guy even changed the spark plugs, cap, rotor, and wires every 20,000 miles, so I'm thinking that this engine is pretty healthy just the way it is and I might be better off just leaving it alone and building something out of a crate motor.

the truck does have some more immediate problems that need addressing, so I am probably getting the cart before the horse here, the radiator leaks, and it still need a serious backflush.


I tend to go a little overboard when I do stuff, so I figured a new radiator, a good back flush, a new water pump, (even though the old one ain't leaking) and all new hoses should solve any potential cooling system problems before they arise.

 

[HotRodPC]

If you put a new cam in you should use it but for an every oil change situation I would say no you shouldn't need it.

Exactly. I'd almost think if you did, your cam would get addicted to it. Then the one time you didn't use it, the cam would go thru withdrawls and wipe a lobe out.

 

[HotRodPC]

I still think that for what you want, a roller cam is a good idea. More power and efficiency... stock 70's and 80's cams suck.

My bad, I must have been mistaken this for a budget do what works build. For real, have you ever considered the cost of a roller cam, lifters, rockers and .....and .... to install a roller cam? I'd find me a well cared for low mileage as in 100,000 miles or so Vortec motor conversion before I'd go thru a Roller Cam retrofit into an old school 2 piece rear main motor. And if I were going to go thru all those motions, then may as well go LS conversion being GM pretty much squeezed most of the reasonable hp/torque out the Vortec 350's. $$$ vs practicality is what it boils down to IMO.

I do also agree Gramps, get your maintenance done on the thing. Sounds like a very well cared for, unmolested motor, with good records kept and all that, and low mileage too. But, I'm a firm believer in time itself is as much a killer of vehicle as is mileage and your talking about a 35 year old vehicle. Example being, you can probably get a million miles on a radiator hose, IF you were driving this vehicle from coast to coast nonstop. But you'd only get about 50,000 out of it if the vehicle were driving 2500-3000 a month. Time itself will kill the mechanicals of a motor. Rubber valve seals even become hard, as does trans seals, belts etc.

 

[Christian Nelson]

Other than tune up/replace consumable stuff, I'd leave it alone. My experience with older stuff is, the more you open it up, the more trouble you cause. Run it til something breaks, then fix that. No sense in chasing your tail. There is no end to that. I see guys who rebuild an engine just because, and I can't help but notice those guys are ALWAYS having issues with their fresh built motors. Alternately, I've seen trucks that sat for 10 years, someone pulls the plugs, a squirt or two of oil in the cylinders, change the oil and filter, put fresh gas in it, and vroom, thing runs like a champ, and they drive it for years with no issues.

No reason a 350 shouldn't run 250,000 miles if it's been taken care of.

You want more power, let the thing breathe. That's the biggest issue the engines of the late 70's early 80's had. Someone decided jamming a potato in the tail pipe and a ball gag on the intake was a good idea.

 

[HotRodPC]

Other than tune up/replace consumable stuff, I'd leave it alone. My experience with older stuff is, the more you open it up, the more trouble you cause. Run it til something breaks, then fix that. No sense in chasing your tail. There is no end to that. I see guys who rebuild an engine just because, and I can't help but notice those guys are ALWAYS having issues with their fresh built motors. Alternately, I've seen trucks that sat for 10 years, someone pulls the plugs, a squirt or two of oil in the cylinders, change the oil and filter, put fresh gas in it, and vroom, thing runs like a champ, and they drive it for years with no issues.

No reason a 350 shouldn't run 250,000 miles if it's been taken care of.

You want more power, let the thing breathe. That's the biggest issue the engines of the late 70's early 80's had. Someone decided jamming a potato in the tail pipe and a ball gag on the intake was a good idea.

That's what I'm sayin !!! Replace the old stuff that has tendency to weather rot, or rot with age, like belts and hoses. Fresh fluids and filters and Rock it !!!
I put a $100 USED long block in my bro's ElCo. It was from a 74 Malibu with over 150,000 miles. The car sat for several years. A guy bought the car for the trans, crossmember, brackets and manifolds for a crate long block he bought to convert his sisters Jag to a 350. We put the manifolds from the ElCo on it and installed it. The valve seals are dried out so it does smoke at start up for about 10 seconds then clears up. Uses about 1 1/2 quarts of oil in a 5000 mile period and run great. He drives it back and forth from OKC to Ft Worth. No oil additives, No Zinc and it's still the OE cam and lifters as far as we know. Oh, we did put a new timing chain & Gearset on it while it was apart too.

 

[Christian Nelson]

Total agreement here Hotrod!

If ya wanted to replace the valve seals, you could with some rope in the cylinders, bring them up to TDC of the compression stroke, to hold the valves, and pull the springs, etc.. Might not be worth the hassle, I've seen people use an air compressor on the spark plug hole too, but I'd trust something solid like the rope than having the pressure drop somehow, and whoops the valves fell in.

Buddy of mine used ot beat the snot out of an old truck he got that sat for years. One time we were mudding, and he ended up sucking water in the engine. We got it out of the water, pulled the plugs, cranked it over a few times to pump the water out, and slapped it back together, and it ran fine.

These engines can take a TON of abuse before they go down. From what I can tell though, when people rebuild them, either they aren't putting them together right, or the new materials aren't as good, or SOMETHING, because just about every person I know of who took a perfectly good motor that was running fine, and decided to rebuild it had all sorts of gremlins to chase, spun main bearings, collapsed lifters, you name it. ALL sorts of stuff! This is why I always say if it ain't broke, don't try to fix it!

 

[HotRodPC]

I think it's a combo of both on those rebuilds. And taking to damn many short cuts. I've built several budget motors but my moto has been if you're going to do it, take the time do it right. For example. I always spend the $80 to get the rods cleaned, magnafluxed, shot peened, check for twist and big end resized. $10 a rod, it's just good insurance. Most won't do it. Getting some cheap ass $99 rebuild kit from China don't cut it either. I only use famous name brand stuff, like Clevite bearings, and even though cheap, they've been around for years, but Silvolite or Badger pistons. You can still get a budget kit, but don't get the CHEAP kit. I also plastigauge EVERY last journal on the crank and if they are the least bit marginal or close the edge of tolerance, then I'll plasiguage it on 2 sides. You're spending the money and taking the time, just spend a little more time and money and all will be perfect. Total of 3 times it paid off. 2 x had a twisted rod in 2 different builds, and once I had an egg shaped journal on a crank. Those would have been doomed motors and lucky to have gotten 30,000 miles out of them before a rod was knockin.

 

[crazy4offroad]

Here's a good episode of Horsepower TV that was on recently, I know they're talking about a Vortec but still there's a shitload of good info in it...
http://www.powerblocktv.com/player/show_player.php?ep_show=HP&ep_num=HP2012-08

 

[Gramps]

Here's a good episode of Horsepower TV that was on recently, I know they're talking about a Vortec but still there's a shitload of good info in it...
http://www.powerblocktv.com/player/show_player.php?ep_show=HP&ep_num=HP2012-08

nice informative video, thanks for posting it.

: I'd find me a well cared for low mileage as in 100,000 miles or so Vortec motor conversion before I'd go thru a Roller Cam retrofit into an old school 2 piece rear main motor.

I just did a craigslist search for Vortec and it looks like you can get a used one for a fair price, maybe that's the way to go, buy one on the cheap, and build it up.

like this one for $400:
http://portland.craigslist.org/mlt/pts/3359441678.html

the ad reads: "I have a good runnning vortec 350 engine in a 1999 chevy suburban im parting, come hear it run before i pull it. motor will be sold complete from throttle body to oil pan and fan to flex plate. $400.00 firm!!! ***-***-xxxx serious inquiries only"

take something like that and do a reseal on it so it don't leak and run it the way it is, that's what we do with the subaru motors.

 

[HotRodPC]

nice informative video, thanks for posting it.




I just did a craigslist search for Vortec and it looks like you can get a used one for a fair price, maybe that's the way to go, buy one on the cheap, and build it up.

like this one for $400:
http://portland.craigslist.org/mlt/pts/3359441678.html

the ad reads: "I have a good runnning vortec 350 engine in a 1999 chevy suburban im parting, come hear it run before i pull it. motor will be sold complete from throttle body to oil pan and fan to flex plate. $400.00 firm!!! ***-***-xxxx serious inquiries only"

take something like that and do a reseal on it so it don't leak and run it the way it is, that's what we do with the subaru motors.

That's what I'm talking about. Now you get it. Honestly, I think what you have sounds damn good. It's OE and unmolested. Noone has been in it butchering it up, taking crap off and throwing it away etc. You know how uncommon that is for a 78 these days? It's obviously been maintained well and is low mileage. Belts, hoses and fluds and I'd be rocking it. If I did any mods, it would probably only be an Eddy intake to give a little better throttle response and tad bit more low end umph. Run a true dual exhaust and call it good to go.
Take a look at the cost of the roller cam and parts needed to do a roller valvetrain swap in that old school motor vs the used Vortec motor that is already set up roller motor. You could even go with that Vortec motor, and run an aftermarket Eddy Carbed intake and carb. The power will be there for sure compared to the old shcool OE 78 motor. IF, and I say IF, I wanted to do the changes, that's the road I'd take over roller cam retrofitting an old shcool 2 pc rear main motor.

 

[Gramps]

the truck already has dual exhaust, came factory that way, but it's just a single pipe off each side, there's no crossover, which I'm told it should have to be a true deal exhaust.

I'm going to clean mine up and run it the way it is, but will go shopping for a good used vortec to build up as a spare.

you guys got me pointed the right direction, I honestly thought a 350 was a 350 no matter what year it is, and I'm seeing now, that's just not the case.

I watched the video and there's some dress up parts I like , like the valve covers and the water pump, but for the basic engine I have in the truck now, I need to be leaving it alone.

my plan is to clean the truck up and have it repainted and want to keep it rock stock for the most part, right down to the wheels, tries and hubcaps.

for the engine I have now, here's where I think I should go with it:

new radiator, all new hoses, new water pump, change out the timing gears and chain to a double roller, do the crossover for the exhaust, and call it good. am I missing anything?

 

[crazy4offroad]

Main part of the video to pay attention to is the Vortec heads which increase hp dramatically over old school heads, and the simple rebuild they did that netted over 1 HP per cubic inch. The EFI Live setup would be an awesome addition but honestly the waterpump, valve covers, etc didn't matter that much to me. Just be aware of the lift limit of Vortec heads, they bought GMPP heads with the spring seats cut for more lift.

 

[HotRodPC]

new radiator, all new hoses, new water pump, change out he timing gears and chain to a double roler, do the crossover for the exhaust, and call it good. am I missing anything?

Maybe replace the rubber fuel lines and may as well get the safe for ethonal use hose. Since you have a REAL radiator, if you can find a radiator shop, since they are all about out of business now due to plastic disposable radiators being much more common, you could just have that same radiator rodded and cleaned to be like brand new again.

I think you're on the right path of leaving it pretty much stock. There's plenty of modified and butchered trucks out there that can be had cheap if you wanted to do some major mods. These trucks in nice, clean, OE, well maintained condition are few and far between these days.

You are close to right on the 350's. There is really only 2 different versions as far as blocks. The old school 2 pc rear main seal block from 69 and you can actually back up to 68 since the Large Journal 327 block IS a 350 block, and up to 85. Then 86 and later are 1 piece rear mains. So those are the 2 variants. Now, in the 86 and later there is some differences in if they are tapped and drilled for roller cams and lifters. I've got a 94 Long Block here that has all the bosses for a roller motor, but they are not tapped and drilled. By 96 and later, they are all tapped and drilled for roller valve train. 96 and later also have the Vortec Heads which is instant bolt on horsepower. About 40-50 hp depending on your total combination. So technically speaking, I consider the 86-95 350 bastard step children. The good stuff was thought about, but didn't quite get it. You can tap and drill those blocks though since the meat is there to do it. Just alot of work.