Running an Elgin rv” grind in my 350. Not the MTC-1 equivalent It’s a different grind but still considered an “rv” by them. Don’t have the specs but it’s a lower rpm cam. Similar engine. 350, dished rebuilder pistons with 194 valve double hump heads. Does what it’s supposed to do. @Fordors lifters? Brand? I’m curious as well. I will be purchasing soon. The ones most recommended here are Johnson’s Howard’s And OE gm
Competition Products sells Elgin cam & lifters as a package , I've had 4 of their sets & not had any trouble ....
Thinking this might work.... About the right specs. I've used them before, a couple bucks more but well worth it. Lunati makes an almost identical grind as well. https://www.speedwaymotors.com/Clay...mith-Hydraulic-Camshaft-Lifter-Kit,80455.html
Spent a little time today cleaning up the heads I acquired this week. They look pretty nice as they are. Good guide plates, 3/8" screw in studs, I pulled a couple valves and they are just as the fellow said, very fresh. I'm very happy with these. They come in right around 62cc so I'm assuming one cut at some point in their life, although I have heard of 461's that were 62cc from the factory. They are dead straight however and no cracks or other crap. They have one hole in the top oil rail only, (didn't hit any water), that was put in to attempt to run later accessory brackets. Nothing a little PC and a bolt won't cure. I'll cut it flush and nobody will notice. They came off a 383 and track use. You can tell they were running tap water, no coolant, by the crap inside which will clean out pretty easily. They have never been ported,(excellent!), so I'll just do a light port match before they go on. I'm happy.
Id check the spring pressure . Those springs look a bit much for a mild hyd RV cam and bit much for what your were thinking
I don't have the ability to check spring pressure but I'm sure it's up there. I'm going to use a good quality hydraulic cam and lifters along with hardened push rods so I don't think I'll have much of a problem. I have a set of stamped steel roller rockers, a 1.5/1.6 split set that I could use. I should probably just use stock style stamped rockers but the rollers wouldn't hurt anything. I myself have never broken one although I hear the usual stories about losing rollers into the galley. No preference either way.
That cam is just a fraction more than the old 327/350 hp cam. Couple more degrees at 0.050, and nominally 0.008 more lift. Essentially negligible amounts, should work fine for your light car. I would think about matching springs, too much and the pressure on lifter/lobe interface may cause problems. Springs for relatively low lift and flat tappet are cheap.
You don't want to break the cam in with some big heavy springs . Id recommend removing the inners for the break in at least . Any shop can check the spring rate at your installed height for a few bucks . there are even tools to check them on the heads . Watch that the stock rockers do not hit the larger valve retainers . I had that happen once. Extra stiff springs are hard on the cam , Hard on stock rockers and push rods an need more horse power to work them . If there for a solid roller cam ( I dont think they are ) they will not go well with a HYD street cam . Amazing what a set of early standard size z28 type springs can support on a under .500" lift cam .
I just visually compared them to a stock 307 head I have here and it is a huge difference. I'll see if B&Y Machine can check them for me. Once again I've made what should have been a cheap junkyard engine into the money pit. Sometimes I just can't resist screwing myself. Hopefully it will run half decent when I'm done.
I see valve springs with dampers .not necessarily hi perf. You didn't mention what condition the guides are in or whether or not there are valve seals . go to your local machine shop & grab some used( worn out) valve springs for break in .
I don't think you realize what not having a proper quench area means in the operation of the engine. Its really not an "option", as the combustion process can be a real problem. It may actually be the reason the engine was removed from service. Met a guy who did it wrong one time and he had to buy octane booster to add to his gas to prevent knocking. Your choice is to either get new pistons or to deck the block. To make your "band aid" approach work, you want to use a cheap head with small combustion chambers. That does not help solve the quench problem. If you deck the block, you can then buy any number of heads that will work. Some heads have different accessory holes. Usually an old set of heads ends up needing to be refurbished and you have as much in them as better newer heads would have cost. I'd deck the block and then look for a decent pair of alum heads to put on it. There are some decent used alum heads out there that will end up costing you little more than repairing clapped out heads. Something to realize is that compression ratio and quench are not the same thing. You can have proper quench and still build for a lower compression ratio.
Good idea on the valve springs. I have a pretty good supply around the shop. I do primarily fabrication work and usually send the motor work out. This is the exception because it's mine and I usually just buy a salvage motor for my own stuff. The heads are indeed fresh. nice valve guides, seals, and everything else. I believe the springs to be some variation on factory high perf. hardware. I honestly don't think they are some insane roller cam territory springs with an insane spring rate. Most certainly aftermarket but not high end. In retrospect I should have bought a $200 283 and called it a day. I missed the whole summer and Fall Wildwood so I have a little breathing room here and I'm not so pressed for time now. This should turn out to be a fairly nice runner after all my bitchin and complaining. I just don't want to be in a situation I've put myself in before where I run myself so far in the hole on a car I need to sell the near completed ride for half or a third of what I have in it just to clear what I owe on the parts. These are the roller rockers I have on hand, They are PAW forged chromoly steel. They are not stamped mild steel. This is a split set, 1.5/1.6, that is new and just weren't used on a motor in here. I wish they had a better roller setup but they work just fine. I've used many sets before.
Regarding the springs, if you have a bathroom scale, drill press and calipers you can measure the pressure at installed height and open height of the cam lift. No, I didn’t come up with this on my own, just relaying gleaned information
80% of the piston is dished and that 80% has 4 eye brows cut into it . you never going to get what the guys on the internet call proper squish , quench, clearance with those pistons even if you had them .005 out of the hole . with a thinner gasket the actual deck of the head is likely with in .010" of were many factory built engines are in relation to the piston. Id wager there is not 5 HP to be gained if it had .040" or .075" piston clearance with those dished pistons IF the actual compression was kept the same . if it was a true flat top it would be different . considering those heads on a true flat top 4 eye brow piston that is .005" in the hole would run fine with about any cam at 36 degrees of timing on pump gas I doubt he's going to be needing octane booter with the dished pistons . the fact big chamber heads on the same pistons still ran OK the smaller chamber heads will be better yet . Not Ideal but its not some deal breaker on a used engine hes doing for cheap . would it be better zero decked ? sure maybe a little but I doubt its going to be noticeable in a street car . I have a 1988 350 out of a truck sitting here standard bore 100% factory . the pistons are .040 " down in the hole on one end and on the other there . 039" thats with a factory thick gasket that near as I can tell is about .030 used . so its about .070" from the head . the OPs' engine with .050" in the hole and a .028 gasket is only .008" more . its not going to make a 5 HP differance and Id bet the timing needs are about the same . Hes out about $35 for gasket if it doesn't work out well and his time . Id more concerned if it was a 10.5 to 1 motor and iron heads and pump gas with a cam that made high cranking pressures . For him to deck the block and buy cheap aluminum heads hes going to be in to it for about a grand on used bores and internals . he woudl be better off jsut buying new piston and going flat tops as well IF the bores are correct for what he can buy . that going to be about $150 for some plain cast stuff . he would at least show a goin and be in the 9.75 to 1 range or so . About 10 years ago we did a dyno run on a 350 with the same 461 heads and flat tops 4 valve reliefs . It was right at 325 HP with a small cam and the single plane torquer intake . ( your basic 350 pump gas build ) He hurt a valve and cast in seat when a spring broke and the easy solution was to just open the intake seats up to 2.02 from the 1.94 and replace the valves . Back on the Dyno the engine was worse up to about 4500 and then showed about 5 hp more to 5500RPM the 202 valves did not really help with the stock ports and every thing was the same . Rings had about 5000 miles on them from one test to the other . personally as far as I know we used the same part number gaskets on both assemblies . On a street 350 with a automatic id have stuck with the .194 valves and had the better low end power were you actualy drive the car at.
I’ve never heard/read a good quench is for HP, but I guess it allows one to squeeze (no pun intended) a few more HP out of it, I was under the impression it was to reduce the possibility of detonation. But I’m far from an engine guru.
I’d get some cheap-o z28 style springs and bolt the heads down with whatever thickness gasket the parts store had. the OP just needs an engine that moves the ride down the road. This ain’t rocker surgery
I'm just fine with the 1'94 valves and the springs on there. I would have liked to drop the 40lbs. of weight but not worth it for what the aluminum heads cost. The cam swap is worth the effort for sure as at least at that point I know what I've got. I'm using a fresh Holley along with a decent dual point Mallory. None of this stuff is cutting edge but it does have a certain amount of nostalgia for an early 1960's style build. All of this stuff would have been typical of the era. Had a 350 been available back in '62 this would have been a pretty good street motor and it will probably make as much power as a 327 of that vintage. There's several sets of 'trips available on Marketplace for around $500-600. If I can get a set I'll do a bit of rebuilding and even cooler for the era and run great, (albeit with a bit less power than the Holley).
Every time someone is building a Chevy you get the “buy new heads” or the “you can’t build em as cheap as you can buy em” or “just get a crate engine” That might make sense on other forums but just seems odd here. Why build a car in the first place when you can just buy one I guess.
You are absolutely correct. On this forum building one can be as much fun as having one to drive. I've noticed this as a sort of sign of the times lately. Most gatherings are for the bought cars. We've become almost a counterculture thing. Believe me, the only way I'm going to have a rod of my own is if it's build pretty economically. Lots of good advice in this thread but I'd be willing to bet most guys back in '62 had no idea and just bolted shit together and hoped it ran, (at least some of the time). I hope we've progressed from there but I have to admit it can take some of the fun out of it. At any rate, all the information I'm gleaning from this thread is being carefully considered and a lot of it is being put to use. Two weeks ago I was going to just throw the smogger heads on and find some used valve train parts. Now it's turning into a fairly nice motor. Thanks guys!
I need to go back to the original intent of this thread for a bit. I'm not a total novice but I'm well aware of most of the stuff we have discussed here. My question was in essence, how bad is this going to suck? I was hoping guys with experience could pass on their thoughts on a less than optimum combination and my concerns have been answered by several people. My intent was to run this for at least a year in as close to "as is" condition as possible. I know it is not a perfect example by any means. To sum up where I'm at, with the 64cc heads I've got I'm going to get about 8 .5 +- static compression. Pump gas territory for sure. If I swap out the pistons, which will add about $750 to the cost of the engine, I will be in at about 9.75 or so, high test territory for sure but still street manageable. I have ordered the Clay Smith cam, which as 38Chevy454 mentioned is a pretty close repop of the old 327/350 hp GM cam. I've used these many times and they are a great street cam of good quality and US made. I ordered the recommended springs, retainers and a new set of seals just incase when I open them up. These heads are really nice otherwise. I'm using the dual plane Weiand along with a new Holley dual feed 650 up top, (maybe a set of Rochester trips), along with the new water and oil pumps. Hopefully I'll be able to just stone the bores a tad and use a set of KB or Speed Pro pistons if I decide to change them out. All in all not a horrible small block. If you have perused my build thread on the Vicky you will notice this is the fourth engine I've built for this car. All the other ones I ended up having a bunch of cash invested and I passed them on the other guys just to get my parts money out. Not good practice as I took a serious loss on each one. If I fire this one up and it runs well it may meet the same fate and I'm back to square one which is what I'm trying to avoid. Hence the reason I am being cheap on this one. One or two of the past motors I've built for this car. There was another 327 that I don't have any pics of. I will add, the 389 ran like a raped ape. I had more in the heads than I do in this whole motor. The 292, (283) was just a sweet sounding motor in PowerPac trim including solids on the old Crane cam.
@1biggun said: 80% of the piston is dished and that 80% has 4 eye brows cut into it . you never going to get what the guys on the internet call proper squish , quench, clearance @Budget36 said: I was under the impression it was to reduce the possibility of detonation. (Yes, that's correct) I asked the question once about how you could maintain quench in an engine with low compression. The noted journalist explained it to me. The compression ratio essentially has nothing to do with quench. By that I don't mean that it doesn't play any part in the compression ratio, only that you can build to have any compression ratio you want and still have proper quench. The dishes and valve reliefs do affect the compression ratio......but around the outer circumference of the pistons top there is usually some flat surface. The distance from this surface to the bottom surface of the engines head is where quench resides. Yes, making the quench distance larger or smaller will have some effect on the overall compression ratio because its part of the compressed volume contained above the piston at TDC. The point simply is that the initial combustion process works better when it starts in the smaller confined space between the flat part of the pistons top and the bottom of the head. Not having quench or the proper amount of quench to start the combustion flames travel across the chamber can lead to detonation. Realize that quench is not the whole top of the piston, because there is a combustion chamber rising into the head to accommodate space to open valves and expand the burning gas. Quench is only basically where the bottom surface of the head is flat......and slightly above the flat surface of the piston. Even if you had a completely flat top piston, quench would not be the whole top of the piston because you have a combustion chamber above most of it.. "]www.motortrend.com/how-to/ideal-quench-height/[/QUOTE]
While new pistons may come with a better quench, realize that it doesen't matter if you raise the compression ratio if you still have poor quench. See the article I attached above. You may luck out or you may not, but check the pin height of your current piston and the ones you may order. If the pin height is the same, the quench will be the same even if you changed the compression ratio. Basically you need to calculate what deck height and gasket thickness you need. I'd just mill the block and reassemble it. There is nothing wrong with keeping compression low so you can run regualar gas because you drive a lot. I fool with old 472/500 Cadillac engines and they built many of them with 7.5 compression ratios.
Great explanation! I most certainly understand the importance of having the motor right. However, if I have to spend another $2,000 between pistons, rings and machine work to get this thing dead on and then sell it to somebody for $600-$800 is kind of foolish as that's all good running 350's are going for around here. I would have just bought one and threw it in here but you never know what you're getting and the good ones go for the same money as the scrap. In answer to some earlier posts, when I'm done with this one I'll have about the same in it as a base crate motor. It will still be a run of the mill, 250 hp, iron head Chevy but it should run reliably. My assumption is these pistons are rebuilders with higher pin locations to maintain cylinder volume on a family truckster. I'm going to swap them out for something that is is maybe .010-.015 max. Most likely when I get one of these out they will have a screwey pin height. All of the information above is absolutely correct and you guys are saving me from myself being cheap. Worst thing that happens is somebody gets a nice 350.
Not suggesting that. I'm saying that if you have the block decked you can reuse all the existing parts you have already ....except the gaskets. If you change cams, you need new lifters. If the cam you have is decent, leave it alone. Just put the new heads on it the way it is and check to make sure the valves clear the pistons. I would change the valve springs though. That looks like the cheapest route to me. The whole problem is based around the deck height, so just machine the deck height and maybe a thinner head gasket. One of the biggest "ifs" is whether new lifters /cam will make it thru the break in process. Why go there if you aren't seeking anything beyond a slight performance gain? So if you only machine the deck and reuse the cam, you shouldn't have many worries when you fire it up.............
I'm not averse to these pistons so your solution is most certainly logical. My machine shop about went into heart failure when I asked them about just decking the block. Obviously they would like to go through everything at the same time. I think the dished pistons are going to put me right where I want to be static compression wise. I think I made a good call on the cam and as noted above I have different springs coming with it. The cam in there is pretty new but I don't have lifters for it anyway so not a lot lost. I also have no idea of what grind it is although I'm sure it's a typical rebuilder unit, possibly even a regrind. I just this afternoon made arrangements for an Offenhauser/Rochester 'trip setup that will make a tad less power than the Holley but will look pretty cool. They get great gas mileage as long as you keep your foot out of the secondarys. The best part is the intake is a very old one. I may need to have that shaved a bit after the block is decked. The fly in the ointment has always been why the engine was pulled years ago, which we'll never know. It could have been for any number or reasons including possibly the vehicle was in an accident and they just salvaged the engine. Not uncommon for salvaged engines to get cannibalised. When I pull it down I can check all the bearings, rods rings etc. for something that may be amiss.
Mine was similar. Mid 70s engine from a commercial rebuilder. Fred Jones. It was in a 64 vette a friend of mine bought. He built a correct era 327 for it. Didn’t need the 350. Had a stupid lift cam. Engine was in great shape. Rehoned,new rings, bearings and a much more stretable cam. has the rebuilder dished pistons. Traded the 76cc heads off and had a set of 461s rebuilt. Runs great. Pinging? Hard pulls with cheap gas. Normal cruising was fine It was in my school bus. Now it’s in a c40. A lightweight car would probably not experience that pinging. it’s been good for over 30k miles.
I ran a very similar set up in my '46 Plymouth. 040 over 350 with crummy rebuilder pistons. I used a Comp Cams XE262(loved it) single Edelbrock carb(hated it) on an Edelbrock dual plane(mehhh) I ran both 416 heads and later switched to a set of 461 2.02 heads. I preferred the 416's. It was no beast but it sounded great, pulled fairly hard and made the car fun to drive. Fuel wasn't an issue and it was low buck fun. sounds like you will have a fun motor....build it, go have fun with it and learn along the way.
The Jalopy Journal
