Heads or cam? Please help

[samlsn]

Hi, I recently replaced my tired, original 350 with a freshly bored .030 4 bolt main cap 350, with 487x cylinder heads(76cc) and a GM 962 cam. Problem is I underestimated the importance of CR and used flat top pistons with 4 valve reliefs and I'll be lucky if I'm even sniffing 9.0:1.
I'm young and dumb, and on a budget so live and learn. This thing has no pep. Should I install a better cam for the heads, or find a better pair of heads with smaller combustion chambers for the cam?
Thanks in advance for your input, and sorry for any lousy grammer, I sent this from a tiny phone

[b454rat]

heads are easier to change than a cam....

[cableguy0]

A modern cam would be a massive help. That ancient cam depended on a ton of compression and higher octane fuel at the pump. Something like even a comp xe268 or lunati voodoo 10120701LK or 10120702LK would far out perform that cam. You can get by with the heads and if it was me I would start with the cam because its a lot cheaper of an option with the best chance for better performance. Even if you were to swap heads I wouldn't even consider running that cam. Your leaving so much power on the table with a 50yr old design its sick.

[b454rat]

Wondered what that cam was lol....If it's that old, replace it with the 268. They sound great and make great power too.

[cableguy0]

Originally Posted by b454rat

Wondered what that cam was lol....If it's that old, replace it with the 268. They sound great and make great power too.

Its the old 327/350hp cam. Works ok around 11-1 compression and 6000rpm but other than that not so much.

[BossHogg69]

Although 'old school' I was always under the impression that the 487x was a decent head - I'd keep them if it was me. But like cableguy & b454rat stated, you'd be much better off with a modern '268' cam. They are all around proven performers on the street in a mild 350 - of the many I've heard and seen out on the street, they seem to always run well as long as the rest of the combo is pretty well in line.

What carb and intake are you running? What's your ignition setup? Sometimes a little tune up/timing adjustment can really wake an engine up also. Just a thought, but you might get a timing light and a vacuum gauge on that thing and do some tuning before you bust into that motor.

[crazy longhorn]

Think about how you use the truck....hotrod, or hauler? On the Xe-268, she will like 24-2500 on the stall, & a tad lower rear gears.(4.10) The Xe-262 , will be a little more street/tow friendly, with a tighter converter/ taller gears (3.42-3.73). The 487 X heads that you have, will run nice.....& you can up grade later On the street, even with a small cam, drop the big heads on....sit down, shut up, & hang the big F on! Its all about useable tork....longhorn

[crazy longhorn]

Originally Posted by cableguy0

Its the old 327/350hp cam. Works ok around 11-1 compression and 6000rpm but other than that not so much.

I differ with you....not a fight, but that old 327/350 cam was a 151 on the casting? Longhorn

[samlsn]

Originally Posted by BossHogg69

What carb and intake are you running? What's your ignition setup? Sometimes a little tune up/timing adjustment can really wake an engine up also. Just a thought, but you might get a timing light and a vacuum gauge on that thing and do some tuning before you bust into that motor.

I have an edelbrock 600 cfm, which I tuned with a vacuum gauge and a torquer single plane manifold. Hei distributor with gaps at .045 and roughly 10° initial advance, 10-15 vacuum that stops sucking around 2,000rpm, and 20°mechanical, for a total of like 35°all in. Headman long tube headers connected to true dual flow master mufflers.
I recently had hand surgery to reattach a tendon I severed in a woodworking accident, but as you can see in the pic, it's pretty much all healed up so I'm ready to get it dirty again!

[samlsn]

Oh yeah, 3.08 rear diff

[picklito]

Sorry, didn't see your distributor specs, above! I'd try 14-16 initial, which will put you at 34-36 mechanical. Vacuum will be added to that.

962 wouldn't have been my first choice of cam, but really quite acceptable. I'd go through your distributor before you change anything else. Especially if you have the stock advance curve in there, you're gonna need more initial timing while limiting total to "somewhere in the 34-40" range. Hard to tell without testing. But if you're at 6 or 8 initial and a stock curve it could really be a dog until rpm's come way up.

[68post]

Your bigger problem is the single plane intake and the 3.08 gears. You need a dual plane intake, gears and a small stall. Or a dual plane and a smaller cam.

$.02

[samlsn]

Originally Posted by 68post

Your bigger problem is the single plane intake and the 3.08 gears. You need a dual plane intake, gears and a small stall. Or a dual plane and a smaller cam.

$.02

Good point, I actually have my intake listed on Craigslist trying to trade for somebody's dual plane.
And as far as torque converters go, I need to start googling 'cause I know nothing about that part of it.
I can't thank you guys enough for the advice/knowledge

[samlsn]

Would I benefit by switching to 1.6:1 rockers? I've read mixed opinions, and also inconsistent views on weather they are a direct swap, or need to check for coil bind/pushrod length, both of which I've never learned to do

[68post]

Originally Posted by samlsn

Would I benefit by switching to 1.6:1 rockers? I've read mixed opinions, and also inconsistent views on weather they are a direct swap, or need to check for coil bind/pushrod length, both of which I've never learned to do

Some engines will have a small gain and some will have a small loss, but the chance for interference is very likely (also valve spring bind). Not worth it on an assembled SBC engine.

[GASoline71]

Originally Posted by BossHogg69

Although 'old school' I was always under the impression that the 487x was a decent head - I'd keep them if it was me. But like cableguy & b454rat stated, you'd be much better off with a modern '268' cam. They are all around proven performers on the street in a mild 350 - of the many I've heard and seen out on the street, they seem to always run well as long as the rest of the combo is pretty well in line.

What carb and intake are you running? What's your ignition setup? Sometimes a little tune up/timing adjustment can really wake an engine up also. Just a thought, but you might get a timing light and a vacuum gauge on that thing and do some tuning before you bust into that motor.

The only "good" thing about them is that they have a 10cc larger intake runner than a non "X" head. They came in either 1.94 or 2.02. They came stock on my 1972 350 in my GMC.

Decent head... but not really a performance head.

Gary

[cableguy0]

Originally Posted by crazy longhorn

I differ with you....not a fight, but that old 327/350 cam was a 151 on the casting? Longhorn

Those are the things that only old people know . Those cams were 20+ years before I existed. No fight at all. Main point is that the ancient grind isn't doing him any justice. Thanks for the correction.

[Marv D]

samisn,, that hand looks nasty!!! Kickback?

I had a piece of oak refuse to go over a dado blade and kick back. Pushed the oak into my right palm enough to damage tendons and 15 stitches, and of course the left hand was right on top of the dado when the oak exited the back of the table. Tips of 3 fingers and part of my thumb hamburgered before I was smart enough to pull out. Doc spent an hour trying to pull pieces of the nail bed around and stitch it together. Other than the fact that my finger tips are numb meat and no bone for the last ~ 3/8" .. ruined my chances for a carreer as a safe cracker LOL

OUCH ,, buddy I feel your pain.

[68c10owner]

Originally Posted by cableguy0

Its the old 327/350hp cam. Works ok around 11-1 compression and 6000rpm but other than that not so much.

Originally Posted by crazy longhorn

I differ with you....not a fight, but that old 327/350 cam was a 151 on the casting? Longhorn

I believe the 962 cam is the 350hp 350 L82 camshaft. Very similar to the 151 cam and almost as old. Lazy lobes for sure but worked ok in my 290hp 350 crate engine that came in a 65 el camino I had. A modern grind would do wonders here as you guys already know.

I have to agree, heads are easier to change but then your held back by the 40yr old camshaft tech. Your basic long block is ok. I would do a camshaft swap. A modern grind is going to be more aggressive and build more cylinder pressure which means more power. I wouldnt worry about the compression. More compression would make more power but its not a issue with this build. Besides, the camshaft doesnt know what compression the engine has. I`d change the cam and then down the road maybe change the heads.

This cam would be about the biggest I`d go with your set up.

http://www.summitracing.com/parts/lun-60102lk

Might even like the next one down better, the 60101. 1.6 rockers can help but you will have to drill out your pushrod tube holes in the heads and for this set up I dont think you would see much improvement.

[samlsn]

Originally Posted by Marv D

samisn,, that hand looks nasty!!! Kickback?


OUCH ,, buddy I feel your pain.

Thank you.. it actually happened without power tools, I was cleaning up a dovetail joint with a 1/4" chisel...and right when I was pushing with all my might because it was such a hard species of wood(santos mahogany), it slipped out of the corner and plunged into my hand. I was soooo pissed!

[AcampoDave]

This is a truck forum not a surgery forum. Do we really need pics like that? Especially first thing in the morning as I eat breakfast. Come on show a little decorum here. It's not that I am overly squeamish, but if I want pics like that I can easily find them on a different site.

[cableguy0]

Originally Posted by AcampoDave

This is a truck forum not a surgery forum. Do we really need pics like that? Especially first thing in the morning as I eat breakfast. Come on show a little decorum here. It's not that I am overly squeamish, but if I want pics like that I can easily find them on a different site.

I think its the perfect place to remind all of us that the activities in the shop can do some real damage if you don't pay attention. Regardless whether its wood or metal the tools are dangerous and will hurt you when you get complacent. Its always the things you have done a million times that land you in the hospital.

[AcampoDave]

No offense cableguy, as I respect you, but driving is dangerous too. However, I am not about to start posting gory accident pics to remind us all to drive safely. You are absolutely right about complacency though, on the job, behind the wheel, etc.

[samlsn]

Originally Posted by AcampoDave

This is a truck forum not a surgery forum. Do we really need pics like that? Especially first thing in the morning as I eat breakfast. Come on show a little decorum here. It's not that I am overly squeamish, but if I want pics like that I can easily find them on a different site.

Sorry do you want me to try to take it down

[samlsn]

<---AcampoDave after breakfast
And I'm like ---->