My 312 is getting a new cam! I rode in a truck with a built up 307 and this cam. Think the L82 cam from the vette(Mellings C-410-P). A torquey classic if you ask me. Plenty of vacuum, not much overlap, good power, good sound, easy on parts.

Should be a good performer and fairly easy to tune. I'll let you'll know when I get it swapped in and start to tune it.

Also means that I am tired of having the timing cover seal leaking.

 

Cool You know what the specs are on it?

 

291*/287* Seat to Seat
224*/224* @.050
.450"/.461" Lift
114* lobe center on both intake and exhaust
SAE Timing=IVO 27 BTC, IVC 84 ABC, EVO 75 BBC, EVC 32 ATC
.050 Timing=IVO -3 BTC, IVC 47 ABC, EVO 46 BBC, EVC -2 ATC

Idles at a smooth 700 RPM in the stock compression 307 (8.5:1) with 15 in/hg on the gauge. (Mine is idling at about 16 in/hg @ 650)

Here are the other engine specs.

http://www.nastyz28.com/camaro/z28l82.html

EDIT- Changed the specs to what was on the cam card. I have it installed on a 106* intake center.

 

Should be a nice cam in that 312, keep us up on how it's going when you finish the swap. Might even consider stepping up to 1.6 rockers to get a little more lift out of it.

 

Already have the crane gold 1.6:1 self aligns that were factory on a LT4.

 

I thought the LT4 had a GMperformance parts version of a roller 1.6? None the less you are becoming the swap wizzard of the TBI world. You have a new cool project every week

 

IIRC, Crane made them (1.6 alum SA rockers) for GM. So you're both right.

 

Well I did my gear swap to 3.73s a couple of weeks ago and was fairly impressed. Well I've done some more. Last weekend I put the cam in, changed to 305 injectors w/ 32 psi 454 spring and VAFPR, no other changes except for a fairly rough tune in the chip. It could use some definate changes in the chip still, for one thing it is using a stock L82 ignition timing curve, straight from a camaro service manual. It does have good response, a fair but lumppy idle(requires an open loop idle so far), immediate pull off-idle, good bottem end torque, a great mid-range, and lots of top-end HP. It runs better with this cam and 3.73s than my stock L69/LE9 cam ran with 3.08s. I am sure my mileage went to hell though(Probably less than 20 now, maybe 18 but it is too early to tell). I am still only turning 2,200 rpm @ 75 MPH and using less pedal than ever to hold speed and accelerate. Maybe the cam and gears won't hurt as bad as I thought. Today being my day off work, I did some playing. It went back on the mustang this morning. After about 1 hour of tuning with the wideband to get the VEs narrowed down, I made some pulls. I am impressed to tell you the truth. I wouldn't have thought a cam this mild would have added that much power. I don't know how much the gears changed the numbers though?

With a 5,800 rpm governor (from the old swirly headed 355) and through the mufflers here are the non corrected numbers.

RWHP=272.7 @ 5,500
RWTQ=315.6 @ 3,350

With the 6,300 governor (from the old XE-274 cammed LE9) and with the cutouts open, they're after the X-pipe.

RWHP=300.8 @ 6,000
RWTQ=325.7 @ 3,500

I picked up 27 RWHP with the headers capped but lost almost 25 ft/lbs @ peak. With the cutouts opened I picked up 55 RWHP over my old HO cam through the mufflers baseline. Strangely down low it wasn't as bad only lost maybe 15 at 2,300 through the mufflers. Honestly with the gears I can't even tell that I lost anything. I am not to worried though as I am making almost as much torque at the wheels as a 5.3 does at the crank, but at a lower RPM.

Maybe I will get some track times this weekend. Till then I am having too much fun peeling the hides Need a fund for new rear tires

 

That is awesome.

Dude you truly rule at finding the good deals and making them kick ***.

Bill

 

Well you wouldn't expect it not to perform would you. GM took the crummiest 350 in the middle 70s complete with catalytic converter and made 245 NET HP(at the back of the transmission with all accessories installed and operating) with this cam. That is with the crummy smog castings of the day, a sick 8:1 compression, weak timing curves, lean carb jetting, stock cast iorn intake and exhaust manifolds, small exhaust, etc. Put the cam in an engine with more compression, better flowing intake, headers, dual exhaust or cutout-exhaust, a better induction setup, better timing curve, etc and you will get better results.

 

Yeah but I am not the chevy historian like you are. Hence I am not the chevy master. LOL!!

It is a flat tappet cam though right?

The other question that I have is...

Can you use roller lifters on a flat tappet cam or is that no good? IE using this cam in a newer block that is setup for roller lifters already.

Thanks

Bill

 

The L82 cam is a flat-tapet hydraulic camshaft.

The lifters aren't compatible. The old L82 cam is similar to the ZZ4 cam anyway. It specs out pretty close to the L82 but has a little more lift. The ZZ4 Hot might even make a little more torque.

EDIT- Opps I meant ZZ4 cam not LT4 Hot. Sorry for any confusion.

 

Great numbers, congrats on the success

Any way you could post up the graph of one of the runs, it would be cool to see where it all comes in and the shape of your torque curve.

 

So what did the zz4 come out of? I know you can get the hotcams on ebay for like not that much but where is a good place to get the zz4

Bill

 

I'm running a ZZ4 cam, I got it off a TGO member. Look in the classifieds one comes up pretty often, they're on ebay and elsewhere as well. Pretty cheap, you should be able to pick one up for around $100, be sure you know how to tune though.

 

How do you like the cam. Did you see a big difference after the tune?

Bill

 

It pulled rocker studs before I could find out, it's on the DL right now for quite some time.

 

So do you recommend screw in studs with that cam.

Bill

 

No question about it. Especially since I went with stronger, larger diameter springs. The load is just too much on press-ins.

 

Just got back from the 1/8 tonight. A money race against a friend. I collected!!!! Against a newer automatic 2.0 4 cylinder(gas) VW Beetle I ran the following

R/T=.238
60"=2.198
1/8=9.890 @ 69.08

To his
R/T =.861
60'=2.741
1/8=12.076 @ 56.64

This was through the mufflers shifting at 5,500 rpm. It got a nice tire screech going into second too. This thing runs well for having only 312 cubes.

 

Addition to the thread and proof. I am still getting 18-20 MPG on the highway even at this performance level.