EddieG

Guys, starting my rebuild to my 396/425. Any tips on what cam or cam kit is best for this motor?

Kerrmudgeon

Whatever grind you end up with, do yourself a favour and go full roller, lifters and rockers. Especially with today's oil, and flat tappet break-in failure. Plus the free horsepower you get.

midyear

100% agree....have had way too many flat tappet failures on big blocks over the past few years..roller is the only way to go.

EddieG

Thanks guys. Keep the info coming.

MikeM

Forget what those two guys said!

Just put the stock replacement cam back in it and you won't have camshaft trouble but you will have good streetable performance at an affordable price.

If you want maximum performance, different story. But, you can keep the stock factory replacement cam and upgrade to a 454 block and pick up more performance for less bucks!

vettsplit 63

Mike,
I blew the doors off every 454-450 horse Chevelle I ever raced with my 396-375 HP Chevelle. The short stroke would get em in a quarter every time. Two of em were local Chevy factory cars too. Little Rich kid driver was the owner's son. That is one of my favorite memories.

Ironcross

I have the same engine in a 67 Camaro and its OE cam is the L72-427 cam....But I`m not sure about the rear cam bearing in a 65 as to whether the oil grove is necessary

EddieG

Thanks Mike. I'm always open to good intelligent advise. Can't wait to get this rocket ship on the road.

MikeM

I know whatcha' mean. The 454/450 and the 396/375 Chevelles were BOTH easy pickin's in my Chevy II!

My point was, unless you have some updated heads to take advantage of the roller cams lift/duration, you don't have a lot to gain by spending all that cash to use one. The factory cam works well and shouldn't cause a problem because of adequate lubrication.

Don't know for a fact but I seldom ever see somebody complaining of losing a cam unless it's one of these aftermarket, super duper modern, blah, blah, blah camshafts with the really high tension valve springs.

Like IronCross, I have one of these cams in a '69 396/375 engine. It's the same cam the factory installed 42 years ago and I don't worry about it going flat.

mudbone64

This.

I ain't even gonna get into the flat tappet failure(s) in my 454 so let's just say, finances permitting, I'll never have another flat tappet cam again.

If you really want to dial your engine build in then call this guy:
http://straubtechnologies.com/
Chris will consult with you and help you decide what you want out of your engine. He'll also sell you the parts you need to make the engine run strong and run long. If I ever get to building a 327 for the POS in my avatar I'll be ringing Chris' number.

Stan's Customs

Big blocks were always subject to cam failures...a known problem back in the day because of big block high valve spring pressures ...even in stock motors.

Most of my customers didn't even know what was wrong...they would say it just didn't run "like it used too". Fixed many of them with a new cam.

I learned it on the first one I owned...a 325 hp. SS 396 Chevelle...right after I got out of the Army.

It was sporatic though...many ran a long time with no issues. I always wondered if it didn't have something to do with cam shaft metallurgy.

Stan...

MikeM

For some reason, I recall it had something to do with hydraulic lifter engines? They didn't blame it on to lack of Zinc back then, did they?

427Hotrod

The factory cam isn't bad at all really..but you can also move to some of the *not too crazy* cams that are still made.

I really had great luck with the Crane 256/266@.050 with .580/.600 lift on a 110 LSA in 396-454's. It runs much better than it looks on paper and never hurt parts. Crane lists it as a Marine lobe these days..which is a great sign of longevity. #134691.

I must have run a gazzilion cams through my old 427 and this was by far the best overall running flat tappet one I had in it.

Another choice is the Comp 288 street roller. It's a solid roller...but has mild lobes that won't kill stuff. Use good pressurized lifters and get it on a steel core (with an iron pressed on dist gear)...NOT the austempered cast one. It has 244/244@.050 and .623/.623 lift on a 110 LSA. REALLY nice driving street cam that makes great power too. The thing pulls down to 1000 RPM in high gear with a 4 speed and 3.36's without bucking,,,and will rev to 7000+ RPM if you want to. It peaked HP at 5850 rpm in my oval port pump gas 427 and ran low 11's@123 mph.

A rectangular port 396 is going to have to get some RPM to make any power at all. A hyd roller will be happy to 6500 or so usually...but those heads aren't even going to get started until 5000+ on a 396.

JIM

EddieG

Great info. I'm becoming a sponge. Thanks.

Westlotorn

Big Block Chevy's had issues with the Lifter Bore not being true to blue print, some are better than others. Most work with bone stock cams but when you increase the lift and pressures these had more cam failures than most other blocks.
The Performance guys solution before roller's came out was to blueprint the lifter bores, they would oversize bore them and then install bushings and bore them to the correct alignment. Probably $400.00 labor but it fixed the problem with cam failure in flat tappet big blocks for racers.
This was before the most recent rash of camshaft failures over the past 10 years or so.
I have only lost one cam on start up, I was brought into a project because the owner could not get a new engine to start, they had already been trying to start the engine till the battery cranked to dead. I found they had the distributor hooked up wrong and we started the engine with another battery. Did the proper cam break in, personally I have seen so many cam failures in the past that I keep RPM above 2,000 but under 3,000 for 30 minutes, I know 20 is recommneded but how many times do you get a chance to do this right? The idea is to get the lifters spinning right away so they spin every time the cam strikes the lifter. By the end of break in we had one lifter that would not adjust and hold. This lobe was wiped out already. I believe it was damaged in the prolonged cranking phase of start up. Once a lifter is scratched instead of rotating you are done, it will cup out and destroy the cam lobe. When we pulled this cam you could see the one cupped out lifter and 3 that were starting to go.
I guess the moral is, get your tune up right on before turning the key and do the break in as soon as you have oil pressure.
Another lifter problem area is the lifter bore itself, everyone is very picky on how the crankshaft finish is prepared, how the cylinder bores are prepared, very few look hard at the lifter bores, they need to be smooth and free of any knicks that might delay the lifter break in. A quick polish of the bores with fine emery cloth before your final wash of the engine block is a good preventative measure. Oil these as soon as the block is dry to keep surface rust from forming, the bores are another bearing surface in the engine and can cause failure.

Ironcross

Back in the 'Day...... or so are we lead to believe that 396/427`s had all kinds of problems...I have NEVER experienced any problems ...in fact they were under a 5 year warranty including the vaunted L-88`s.......I suspect improper handling or installation is the culprit and not anything to do with the engines and there machining.....when they left the factory, they were in perfect condition just like the present camshafts and valve train parts when removed from there boxes......

JohnZ

Yes, it is - '65-'66 big-blocks MUST use the cam with the groove in the rear journal, AND the '65-'66-only 3-hole rear cam bearing in order to get oil to the lifter galleries.