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73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: Gramps on October 10, 2012, 03:48:34 am
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I've got a 78 chevy C20 Scottsdale 4x4 with a 350 and a 4 speed tranny, 70,000 original miles.
the truck is rock stock, with no options, and I'll be using it to occasionally pull a boat or a camping trailer, get fire wood, make trips to the dump, ect. the truck isn't going to see a lot of use, it's mainly just a farm workhorse.
the engine is covered in grease, it doesn't look like it's ever been cleaned under the hood.
I'm planning on taking it a shop, have the engine pulled and resealed to get rid of any and all oil leaks, and have a new clutch put in it.
My brother is insistent that I'm going to have cam problems with it if I don't get the cam changed out when I do the reseal and he's suggesting I have installed a roller cam kit.
I have no problems with installing a roller cam kit, and wouldn't mind getting something along the lines of a RV cam, or as is in my Subaru, a "torque cam" upgrade, I really like the torque cams on my little subaru, it sets it apart in both performance and sound from other cars like it, and it helps when pulling my little utility trailer, so have thought about the idea with the truck thinking it might not be a bad idea if I'm going to be towing trailers occasionally.
I did a google search and an ebay search for "Roller cam kits" and found that there's a gazillion different kinds of roller cam kits, anywhere from 300 up to 1,000 bucks.
I got no idea what I'm looking at, and even less of an idea as to which one I want, or if I even need one at all, I don't mind spending the money on one if it's going to help me out, but where do I start and which one do I want?
I know this is a loaded question, but maybe someone can give me a little insight in terms my simple mind and comprehend.
thanks, Gramps
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Why would you have trouble if you are just changing the seals? You aren't removing anything from the block are you? A retro roller kit is a huge investment for an old engine. If you were completely rebuilding it sure, but if you are just resealing it (as in not pulling down the shortblock) I wouldn't do it.
What are you wanting to accomplish?
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Why would you have trouble if you are just changing the seals? You aren't removing anything from the block are you? A retro roller kit is a huge investment for an old engine. If you were completely rebuilding it sure, but if you are just resealing it (as in not pulling down the shortblock) I wouldn't do it.
What are you wanting to accomplish?
Ditto
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Why would you have trouble if you are just changing the seals? You aren't removing anything from the block are you? A retro roller kit is a huge investment for an old engine. If you were completely rebuilding it sure, but if you are just resealing it (as in not pulling down the shortblock) I wouldn't do it.
What are you wanting to accomplish?
Ditto
I agree, as well. Simply resealing the engine will have no bearing on the cam, unless the rear cam plug is replaced incorrectly.
If/when you remove the intake manifold to replace gaskets, you can pull the lifters and inspect for abnormal/excessive wear. If the lifters look okay for 70,000 miles, the cam will be okay, too.
Retrofit roller cams can provide a noticeable boost in torque across the entire RPM range, but will be most responsive if other mods are made at the same time. As already stated, a big investment for a stocker w/ 70K miles, if not a factory service replacement engine with an OE roller from the factory.
Something more to think about - if the engine puffs blue smoke at start up, you might want to diagnose that (i.e., valve guide & seals vs. rings), before you tear it down; it could have a significant bearing on your repair solution and cost.
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I'll add this, as well: All things being equal (bearings and rings are good, etc.), if you are going to add a roller cam then you really should consider better flowing heads (e.g., Vortec).
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I agree with these guys. You'd be putting a lot of money into your 350 that you really don't need to spend, especially if it already runs good. What your brother is likely referring to as far as cam problems with the stock flat tappet cam is losing lobes due to the ZDDP being virtually removed from modern oils. The new oils and old engines just don't like each other very much! As long as you run an oil in it that has lots of ZDDP in it, you should be fine. Comp Cams, Joe Gibbs, Royal Purple, Valvoline, Lucas, and many others make the proper oil for your flat tappet cam to be able to live, and this is what it really boils down to, proper lubrication.
If you are tearing it apart to change all the gaskets and seals out anyway, I'd definitely be checking the timing chain since the cover will be off when you change the gasket and seal They tend to stretch over time, and can cause a boat load of trouble if they ever get loose enough to slip and jump time. It will cause bent valves and push rods...I know this from past experience. Just for the peace of mind, I'd spring for a new double roller set if it were me.
One other thing that I would replace while you're at it that is cheap to replace, and that could cause problems is the stock oil pump drive shaft collar. They are plastic from the factory, and the aftermarket makes a steel replacement. Cheap peace of mind if you ask me, since if that plastic collar were to ever break, you'd have no oil pressure, and a huge disaster would ensue! I use them in every engine that I build up, or tear down such as this. Zero failures. Just my 2 cents. ....Joe