I've got a set of 14101083 heads off my 87 Caprice 9C1 350.

I tried running through the search to try and get some information on these heads, and there's a lot of great information but one thing I was kind of confused about is what is the stock maximum lift these things can handle? Somebody posted flow numbers all the way up to 0.600" lift, and I couldn't tell if that was after modification or stock I never saw where they mentioned that. I'll provide a link for the cam I'm planning to get for them, I just need to know if it'll handle them in stock configuration with 1.52:1 rockers.

From what I've seen people say about them they're either great, or they're average, either way it doesn't bother me. They've got a good size combustion chamber, the valve size is fine, I'm not looking to put down big numbers I just want something fun to drive. If I get 300 horsepower on the dyno at the crank without any accessories on it I'll be thrilled.

One thing I do wish I could figure out though is what the factory cam profile is for that old 9C1... I've seen a couple charts, but I can't find them now. I'm guessing it was probably a step up from the 305 peanut cam, probably similar to the Chevrolet Performance roller truck cam you can find on Summit Racing. 196' / 206' @0.050" and .431"/451" lift.

https://www.compcams.com/xtreme-ener...oller-sbc.html

*EDIT*
I've also seen some videos of guys using this cam and it's also a pretty strong contender, and it has a little less lift so it might just work out of the box. Just wanna be sure before I buy. Thanks!

https://www.compcams.com/xtreme-ener...oller-sbc.html

 

083 is a decent enough head casting. Roughly the same flow, in stock trim, as the old double-hump castings from days of yore, like 186 or 492 or 041.

"Max lift" is kind of the wrong question to ask about stock heads. About like asking what the CFM of a Q-Jet is. Not to be a jerk, but asking that sort of thing shows that you don't understand all the factors in play, just yet.

Stock - TOTALLY stock, as in, brand new the day they rolled off the production line - everything except the valve springs was good for something in the .480" - .500" range. Being a CASTING, and lots of the factors at hand being determined by their AS-CAST features, there's ALOT of variability in that.

The difference in lift between those 2 cams is negligible, for the purpose at hand. It's roughly the thickness of a sheet of 24 lb printer paper. Not exactly the kind of distinction that can be made when talking about AS-CAST CASTINGS. Let alone, after they've had a valve job or 2, some wear on the valves, and so on. Let alone, the difference between stock stamped rubber rockers, which deliver a MEASURED ratio anywhere between about 1.38 and 1.45, with most of them being in the 1.42 kind of area. What "worked" "well enough" for the factory, isn't going to cut it if you're going to try to push the limits.

One thing is absolutely positively 100% ironclad guaranteed without doubt CERTAIN though: stock valve springs won't cut it. For that matter, both of those cams are at the extreme outer limit of ANY 1.25" OD straight spring. And, for such a spring to have a chance of long-term survival, very careful attention to detail would be needed: particularly, getting the installed height EXACTLY right. 1.750", to within .005" or so. Not a job for a shadetree to reliably accomplish without the specialized measurement tools. And even then, they won't be able to do an adequate job of controlling valve motion; that is, you would be able to tell an A-B difference between those and better springs with no other changes, in nothing any more complicated than just the way the engine runs measured from the seat of your pants. Even a stock cam will run better with better than stock valve springs.

My recommendation would be, LS6 springs, the Comp "adapter" retainers (787) with their matching hardware, and set up to about 1.78" installed height; and the larger of those 2 cams.

 

9C1 cars shared the same L98 cam that came in Camaros and Corvettes. 207-213. 415-428 lift. GM #049. Im running those same heads with a bit of porting and the stock cam on an upgraded TBI unit on my car and it pulls really well. I think as a crate engine without accessories the iron head L98 made an advertised 285hp iirc.

 

I think Mercury marine 350s used the same 083 heads and had a rating of 270 hp (marine engines have few accessories). So if I had to guess with a decent cam and intake you should be able to get 300 hp at the crank.

 

Fair enough, though I suppose I wouldn't be asking if I did. I don't think you're being a jerk, just stating the obvious. I mean, I've got a basic understanding on engine building theory, this is just my first time actually doing it so as I work my way through it, I've been reading articles from old magazines, browsing forums, watching videos, and asking stupid questions trying to figure things out before I destroy the engine I'm trying to build lol.

(I'll probably still mess up somehow, but I'll cross that bridge when I get to it)

Okay, so the question I should have asked is whether or not the heads - in their stock configuration, without any machine work - will support the proper springs needed to support that cam, rather than what I did ask, which is whether or not the stock springs would cut it. What my caveman brain can gather from what you said is, as long as I use the right springs, with the proper hardware, and as long as I make sure to do my part and ensure the proper measurements before I send it, it should work.

Looked up what you recommended, and this is what I found:

Chevrolet Performance 19420455 Chevrolet Performance Valve Springs | Summit Racing
COMP Cams 787-16 COMP Cams Steel Valve Spring Retainers | Summit Racing

Those are 1.8" installed height springs, so I need the retainers and +.050" offset valve locks to start, and then I'll have to measure the open height, and closed height of the valve with the retainer installed.

In the end, much cheaper than buying new heads, and I'll be able to use the stock manifold to maintain that stock look. It won't blow anybody away with gobs of power, but that does sound like it would be fun to drive, and most importantly, it would be serviceable even by a Neanderthal such as myself.

Thanks for the help

 

That had me intrigued for a hot minute, but I did a little searching and found that the '87 L98 cam was 202/206 @0.050" with .403/.415" lift and 114.5 LSA P/N 14093643

The cam you're talking about was indeed in the L98, but from model years '88-89. It had a 117' LSA in addition to the specs you mentioned. Full P/N 10066049

Still, not bad. If you're right and the 9C1 came with the same cam as the Camaro, I might just leave the cam, and install the better springs, roller-tip rockers, and get a set of pistons to up the compression. I'll also think about taking the heads to a machine shop to get new valve guides, and new valve seats installed so I can put 2.020" and 1.6" valves. If I ever want to get more performance down the line all I have to do is install 1.6 ratio rocker arms to get a little more lift.

 

You are right on the cam. Supposedely 90-92 went back to the same cam used in 87. I was also thinking the 9C1 cars had the TBI heads and not the #083s???

 

Maybe some of them did? Maybe it depended on how the department ordered the vehicles, maybe it was an option.

All I know is that mine came with 14101083 heads, and I have pictures to prove it lol.

 

Cool. Basicly an L98 running TBI then. Pretty much what Im running

 

Well, except I'm running a Quadrajet which is also what came stock on the Caprice. GM P/N 14101076 dual plane spread bore intake manifold. I'll take the simplicity of a good carburetor over a TBI or TPI set up any day of the week. lol

 

Hey, where did you find my selfie???? I took that 45,000 years ago with my brick phone.

That's not right. The installed height is a property of the castings, the valves, and the retainers. In a word, it's the space that the spring is squoze into, NOT a property of the spring itself.

The nominal stock installed height of a SBC with nominal stock hardware is 1.700". In reality, it's all over the place, usually somewhat greater; and ALWAYS greater, after some wear and some valve seat grinding. BUTTT: there are ALWAYS shims under them, and on the exhausts, there's a "rotator" that's about .125" (1/8") thick, as well which is DEAD WEIGHT in the ABSOLUTE WORST POSSIBLE place in the valve train (it absolutely positively needs to go straight into the trash RIGHT NOW). So, the trick is, use your spring micrometer (you have one of those, right? that's one of the tools I was referring to; something kinda like this https://www.summitracing.com/parts/pro-67390 ) to find the height with the valves and retainers you're going to use, then stack shims https://www.summitracing.com/parts/cca-4753 under the springs, of a thickness such that the height you measured, minus the thickness of the shims you put in, comes out to something in the 1.75 - 1.8" range, NO GREATER THAN 1.8" under any circumstances.

I'm no expert on factory cams or heads or any of that, in 9C1 cars anyway. You've got what you've got, and arguing about "this motor came with that [thing]" gets you exactly nowhere. Total waste of time and ... bishop buffing. But I'll tell you, I used a XR264 in the 305 (don't ask) that's in my Camaro right now, with 186 heads, and got 237 RWHP and 273 wheel ft-lbs of torque, in California, therefore with the stock Q-Jet carb, all emissions devices installed and operating INCLUDING EGR and AIR, stock air cleaner, catalytic converter, full exhaust, California watered down cat pee in the gas tank. That's somewhere very close to 300 HP and 350 ft-lbs at the crank. Around 16" of vacuum at idle. Around 21 mpg on the highway (3.73 gears), 14 - 15 around town. The A/C blew nice and cold. Your build, with the same cam, should do better than that: if it is otherwise equal to mine, it should put down around 340 HP and 435 ft-lbs at the crank, and still get stock gas mileage, idle vacuum will be around 19". IOW, no problem with power brakes, A/C, or any of that; assuming of course, equal attention to detail in the short block and head assembly compared to mine. Very close to 1 HP and 1.25 ft/lbs per cubic inch is not too shabby with a carb from the Stone Age, while retaining stock-like driveability.

 

Very fancy! Most cavemen I knew had to make due with finger painting the walls! Don't ask where they got their red and browns from.

Okay, that makes sense. In other words, I'm making sure that the space between the spring seat and the retainer doesn't exceed the specification. Seems simple enough.

I might actually have one of those tools in my garage already. Most of the tools I've got I inherited from my grandfather, so I've got plenty of tools that I have no clue what they're for until I need them, and I look up what they are, or somebody tells me and I'm like, "Oh! I've got that!"

If I don't have one, then I'll just be adding another tool to the collection for somebody else to eventually snap up cheap in the estate sale lol.

I've got a bunch of tools he hand made for specific jobs too, which is kind of neat. I've added my own contraptions to that collection a few times over the years, but that's getting off topic.

Well, the factory part number for the cam should be somewhere on it if what I've read is correct. So honestly my best course of action when I get home from my Saturday shift here at the stealership, is to dismantle the engine down to the block and rotating assembly, start inspecting parts, to see what can go along for the ride and what's wasted and needs replaced, and do measurements to find out what kind of condition the cylinders are in and get everything ready for the machine shop... if I've got it down that far I might as well... in for a penny, in for a dollar. I'll pull the cam and see if I can't find that part number. If the cam I find in there is what I expect it to be, and it looks good, then I'll ride with that one. Probably. Unless I change my mind. I've got plenty of time to think about it, it's not like all this is going to be done overnight.

Hopefully the block will only need a hone job after getting cleaned up, but I thought that would be the case last time and I ended up with a boat anchor that they let me slide on. They kept the core for scrap and I got off Scott Free. Then again, the internals of that engine were absolutely wasted and I knew that before I even had it all apart... had a hydraulic flat tappet cam that was chewed up so bad you'd think it came out of a modern HEMI. Multiple lobes worn off completely and the tappets had nice, sharp little domes on their bottoms. I also thought it was going to be a 305, but it ended up being a 350 bored 0.030" over with a nice big crack in the lifter valley that you couldn't see until the machine shop got all the sludge off of it.

I've actually still got the heads from that engine... I forget the casting numbers, but I'll look them up later. I'm pretty sure they're (s)crap low comp heads but we'll see.

As far as power goes, like I said... if I can manage to get 300 at the crank with no accessories on it then I'll be happy. Luckily for me though, I live in CT so there's no emissions inspections on cars older than 25 years.

 

Do you have this intake yet and do you know what it came from? Thanks