BillZ260 Posted April 5, 2004 Share Posted April 5, 2004 I started tearing down the Vortec I got last week. The lower end HAS been rebuild but VERY VERY recently. I have a couple of questions about this new style bock. Are these roller motors? I guess I will find this out this evening if i can get to it, the lifters have flat spots and a keepr that keeps them from rotating, so I am thinking roller lifters right? But no roller rockers There is a crank trigger on the front just behind the Ballancer, any thoughts on what I could use this for? I am going carb for now and wondered what I might utilize this sensor for untill I can afford injection. The ballancer is 7-3/4", it needed to be 7-1/4 right? How much clearance is there? If I bump the mounts back in the "slotted" poition can I clear? The main caps are "only" two bolt but the bolts are bigger than the old style, 5/8 heads instead of 9/16, the spacing looks to be a bit wider and over all more BEEFY The rods are also wider, again BEEFY. I am happy with the overall condidion, the bottom end (as i said before) has been gone through, every thing is number stamped and the xhatch at the bottom of the cyl's is still there and sparkly, could not have hardly any miles. The ONLY concern of mine is what I found in the lifter galley under in intake. The oil was glossy and caked on the walls of the galley and there were several chunks! of this porus oily coal type crap. Big chunks and I am sure there were a lot of little chuncks lost in there too. WHat is this stuff? Never seen it before. Thanks for your thoughts, I am hoping to stay mostly stock in as is condition, of course I will take the entire assy to my machinist to have cleaned and I will put new springs in the Vortec heads. If this is a roller, will have to think about putting a differnt cam in, thoughts? Should I match the roller cam with rockers while I am at it? Just can't seem to stop typing. Adress what you want, I am all ears! Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted April 5, 2004 Author Share Posted April 5, 2004 Apparently this is the stock cam specs for the L31 5.7 V8... HR 202/207 .410/.424 115 L31 Vortec Any comments??? 225 HP and 330 Ft lbs. I think for the sake of time and money, i will try to reuse the stock cam unless someone can convince me that a different cam and the expence of modding the heads is worth it. I am open to suggestions but 330 ft lbs is looking good! Plus i don't have to break down the heads. I won an Edelbrock Performer intake on ebay and looking at a used Edelbrock 750 for now. Just FYI. Quote Link to comment Share on other sites More sharing options...
wheelman Posted April 5, 2004 Share Posted April 5, 2004 BillZ260, Where in the RPM range are the HP and torque peaks? Remember this is a truck motor which means it was probably designed more for low end torque than high or mid-range HP. You might want to explore switching to a cam that moves the peak HP up in the RPM range depending on where it is right now. Just a thought as I'm not sure where the power band is, what you plan to use the car for or if you plan on running a manul or automatic transmission. Wheelman Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted April 5, 2004 Author Share Posted April 5, 2004 Looks like 300Ft/Lbs from 1500 to 4500. This will be mostly a daily driver with a T-5. Do you know if this is a roller? Quote Link to comment Share on other sites More sharing options...
dmyntti Posted April 5, 2004 Share Posted April 5, 2004 If you have the retainers that keep the lifters from turning then it is a roller. Non rollers need to turn in there bores. The oilly crap in the lifter valley is broken down oil. It is a sign of either oil not being changed or severe overheating. I had this on the bottom of an intake manifold in a well maintained van I bought. It turned out that the Y pipe was clogged on one side and forcing all of the exhaust from one side of the motor to pass through the exhaust crossover passage in the intake. This craked the intake manifold and ruined two exhaust valve springs. Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted April 5, 2004 Author Share Posted April 5, 2004 I will venture to say something similar happend there then, because it was NOT in the pan. Thanks dmyntti! So, I am looking to replace the stock roller cam with another? I CAN reuse these lifters right? Since they are roller? How much is a roller cam and spring set? Quote Link to comment Share on other sites More sharing options...
wheelman Posted April 5, 2004 Share Posted April 5, 2004 Yes you can re-use the lifters. I've been pricing LT1 cams for the same purpose as you and they run around $300.00. I would imagine a cam for your engine will be similarly priced. I don't know what a spring set is going to run you but while your at it you might as well install roller rockers. I put a set on a Ford 302 years ago and they made a big difference in power and valve stem wear. You'll need to have the machine work done to allow higher lift numbers so include that in your calculations when figuring how much you'll be spending. Wheelman Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted April 7, 2004 Author Share Posted April 7, 2004 Thanks, I will get it to the machine shop on Friday. I will tell him what I am wanting and get his quote. I got the ballancer pulled last night, so I could get the crank and cam out. Crank is out, the cam however, spun a bearing. THe bearing came out of its housing towards the BACK of the enging adn got crushed a bit. The cam will spin but won't come out. Will take it to the machinist like this, hopefully he will have some ideas. The front crank journal is horendous! This engine lost pressure, and although it didn't run long after it lost pressure, it was enough to badly score the front main, the rest are decent. I hope we don't find cracks under all that caked oil goup. If so, I am going to start getting tired of Engine searching!!! Will see... Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted April 8, 2004 Author Share Posted April 8, 2004 Just got back from ALMOST dropping off the motor. My machinist did NOT want anything to do with the spun cam bearing. He said it would never be right, also voted against using the vortec blocks and rods. Apparently they are not forged, they are powdered metal, and break easily. SO I am in search of another block. Hopefully I can get my $$ back AGAIN for this piece of cast bulljive. Man, this is really disheartening. Luckily they guy was selling the block and heads seperatly so I will hopefully be keeping the heads and get my $$ back for the short block. I am going to seriouly look into buying one of those ballanced short blocks from someone like summit or whomever, maybe even a 383 or something. Any suggestions? I am still trying to keep this cheapISH If anyone has a deal or input or ENCOURAGMENT, please subit it HERE!!! I am so bummed right now... This SUX!!!!!! UPDATE Just got off the phone with the guy and he is going to get me another block, will see how that goes... Quote Link to comment Share on other sites More sharing options...
dmyntti Posted April 8, 2004 Share Posted April 8, 2004 Maybe you should contact another machine shop first. There is nothing wrong with a vortec block and the powder metal rods are supposed to be the strongest of the factory rods. They may not be as strong as aftermarket rods but they are good rods. Supposed to be good for 450ish horsepower. I beleive that the cam journals can be line bored and oversized bearings installed. Make some calls to machine sho[ps and get other opinions. I personally like to use speed shops for my machine work. I feel they have better quality and I use them even for standard stock type rebuilds. It is worth the extra money on the machine work to get a better foundation to build from. Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted April 8, 2004 Author Share Posted April 8, 2004 I am going to get another Vortec block, free exchange from the same seller, will see how that goes. I am sure that they are of better design than the old style. My machinist was just telling me what he had seen of them. Another thing is that they are ballanced differently and he said I need a vortec specific flywheel? He is a racer, builder and has been around for a long time. Anyway, this guy is GOOD. Alot of guys use him and as I have said before, he doesn't jack you around. He said you could go .010 over on the cam bearings but that .010 wouldn't have cleaned up that particular bearing journal, the bearing spun and freely slid in and out of the journal. Was pretty nasty. Thanks dmyntti for your input, it does make me feel better about using the Vortec. Quote Link to comment Share on other sites More sharing options...
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