Hi all,
I had recently freshened my old 396 in my 68. I needed to replace the factory cam as it wasnt in the best condition after all these years. I went with crane cams repo of the 375 horse 396 camshaft, and I have to say I hate it. The car seems very lazy on the bottom end, since I only run 3;73 gears. i had broke the original 4-speed 20 years ago and have had a turbo 400 in the car ever since. I do have a TCI street fighter converter in the car that will foot brake around 3200 or so. The rest of the engine is stock 11to 1 compresson and it is 030 over so I guess its really a 402. it still has the factory "840" rectangular port heads and the stock aluminum intake with a 750 holley. I know I could probably solve most of its problems by switching to 4;10 gears but I like to take the car down the highway and it turns 3600 with the 3:73 in it now. I was looking at the Comp cams section in summitt at cam 11-219-4 with is a 294 solid. what do you guys recomend?
Thanks in advance,
Nick

Hello,

I think the big reason you hate that cam is because it is ground on a 114. Similiar to the DZ302's stock cam. Very sluggish and sloppy down low, even with tall gears. TO make matters worse, the 396 being a big block has much more weight to move so it can't even rev like it should. At any rate, i'm gonna assume you have Power Brakes and that you'll need enough Vaccuum to run those, so here are a couple possibilities.

If you get a cam with smaller duration, and tighter lobes, it will idle just like the factory cam, but be 10,000 times more responsive and rip like crazy.

If you want to go with a comp cams, I'd go with either the 294s Magnum which is part number 11-219-4 which is 248@.050 i/e and .595 lift on a 110. That think will rip in your combo. Definately rougher idle than your existing cam, but much more responsive in all ends.

Part # 11-218-4 is the next size smaller, which is 236 @.050 and .561 lift also on a 110. Little more torque, probably idles exactly like your stock cam.

There are two other cams, I really like, one is the Extreme Energy Cam, part # 11-678-5 which is 240/252 @ .050 and .590/.598 lift on a 110. The split pattern helps the upper end ad starts making pulling like a mother at 2500.

If you want to stay factory, Comp makes something called a Nostalgia Plus and a Magnum Muscle, both are cams designed to sound like originals, but with modern designs and techniques. You'll make much more power with one of these, (probably the extreme energy) would make the most, but it depends on your style. Any of these would make a night and day difference over your factory cam.

Just FYI, I restored a 69z about 3 years ago, and blueprinted the motor, and couldn't stand the 30/30 cam, I tried 3 different designs of that style cam, and finially went to a modern lobe design and all I wanted to keep was the idle to sound like a stock cam. The cam I went with was about 15 degrees smaller, on a much tighter lobe (110,as opposed to 114) and the car was a completely different animal. It was still easy to drive, pulled like a mother and never gave any problems like the stock 302s are prone too.

I think you'll love any of these cams.

Imho, go with a CC 282S solid cam AND I bet you will really like it!!!

I put one in my 496 but don't have my motor in my car yet..

pdq67

Have you tried quickening the advance curve? The old factory cam will respond very well to it. The more modern cams are much better but I think you may have some other tune up problems. I just helped a friend with an L-72 69 with 3.73s. His car will turn the tires at will even with an excellent suspension.

Nick,

Are you trying to run on pump gas? If so the 11-219-4 (aka 294S) is about as small as you can go. Even with it your still looking at over an 8:1 DCR on the engine. I'm currently looking at the same cam but I going to run the 842 aluminum heads to help out with the DCR number. My biggest concern is the vacuum to run the brakes and RS headlights. Is anyone out ther running the 294s with power brakes?

Thanks,

Ted

Oooop's, forgot about the 11 to 1 CR. thing... pdq67

rpol hey i have the 294s in my 454, in my 68 i have power brakes but have not driven it, while i broke in the cam i got 10" of vacuum at idle, idle around 925 rpms, i have 840 cast heads,294s, dart sp intake, bg850 carb, what gears should i go with ?? oh ya i got a th400 manual shift kit,3500 stall, ford 9 in need of some gears, what would you run, will see street and strip use, anyway thanks
jake

Hi all,
Thanks for the quick replys.
I had been loooking at both of those comp cams that you guys recomended. I liked the #'s of the 294s the best so far.
I actually have full advance (36 total) in by 3000 rpm. I guess I should have explained the soggy botom end a little better. It seems lazy with slicks on the car. When i have the street tires on it ( 255-60-15s) the car will blow the tires away at will even if you hit it at 40 mph. But with the slicks (26x10.5) the 60' times are terrible. 1.91 has been the best but they are usually around 1.96. I thought if I put a cam that came in a little sooner the 60' times should pick up. The 294s is 2500-6500. My Blue print 396/375 cam is 3200-6500.
RPOL78,
Yes i have been running the car on 91 octane super unleaded with octane boost. And you are right about the vacume, the power brakes seem fine but my RS headlight doors move really slow with the cam I am running.
Thanks again,
Nick

Slicks and 60ft times weren't mentioned in the post. That makes everything different. Even though I like TCI street convertors you might as well change it now before it dies. An increase in stall speed and a better quality convertor should cure your problem. When I ran a motor like yours I usually had all of the advance in by 2000 RPM if not sooner. If you want to change to a more modern cam it will help but they are also harder on parts the old L-78 cam was designed to run for 100,000 mi.

Nick,

If you change to the 294s cam you very well may run into problems running on pump gas. If I use 11:1 and the intake valve closing at 73 ABDC for the 294s in the DCR calculator we end up with about 8.2:1 DCR. With iron heads you probably will have detonation problems. I had a 327 in an old vette running 8.3:1 DCR and was having to mix 10% toluene with 92 octane to eliminate detonation. Comp's version of the L78 shows the intake closing at 86 ABDC (Crane only shows the number at .050 on their online spec card). If I use the same 11:1 and the intake closing at 86 ABDC we end up with about 7.1:1 DCR. That's a pretty big difference in DCR. By the way I've Desktop Dyno'd both of these and DD show a pretty big difference in HP/TQ with the 294s. It's up for debate as to how real the numbers are.

Hope this helps,

Ted

I think you should have a good look at your carb and distributer! I know 4 guys running that cam in the pure Stock drags, all running through the manifolds and on F70-14 polyglas tires. A 69 Nova is running 12.2's, and 2 LS-6 Chevelles are running 12.30's and a couple of 69 427 Camaro's running 12.40's..... all at 110 to 113 MPH. That cam is excellent!
Peter

Copo Pete, good point about the pure stock drags, but remember these guys are running skinny biasply tires so they NEED to kill major TQ down low . . .

I also think a shorter cam with a tighter LSA would help, but I do not claim to be a BBC guru either.

Originally posted by COPO PETE:
I think you should have a good look at your carb and distributer! I know 4 guys running that cam in the pure Stock drags, all running through the manifolds and on F70-14 polyglas tires. A 69 Nova is running 12.2's, and 2 LS-6 Chevelles are running 12.30's and a couple of 69 427 Camaro's running 12.40's..... all at 110 to 113 MPH. That cam is excellent!
Peter COPO PETE,
I am all ears. What do you think I should do with the carb and distributer? Also at what altitude are these cars running the numbers at the pure stock drags? My car has gone 13.20 at 103 at 5300'. I am pretty sure if I were at sea level or close to it the would run a 12.40 or 12.50 just the way it sits. I konw most people dont like to give out all there secrets, but can you point me in the right direction. by the way my car is just over 3800 lbs with a driver.
Thanks Again,
Nick

Nick the 294s is a great choice but you don't drive that car that much on the street anyway to worry about using pump gas. Go solid roller and buy some good gas. We should talk...

Mike,
actually I put just over 8000 miles on it last year. I guess I should have put a little more thought my camshaft before I bought the repo of the stock cam, but I still think the car ran better with the GM version of this cam. I know the car probably just needs more gear.

HELP
Nick

Are your plans to put another 8000 miles in the next year or to just race it? If you are going to continue to drive it that much on the street, you will not be happy with more gear. The 294s is a great cam but you can do a solid roller like mine and drive it 8000 miles a year easily with no problems. You know I don't drive mine that much but the solid roller/street car thing is a myth. BTW, wanna race? :D

Originally posted by 69RS/SS350:
BTW, wanna race? :D Loser buys the beer tongue.gif I plan to drive it as much as possible on the street. Heck I even want to do a couple legs of the power Tour this coming year if they are back in this neck of the woods. You know what the deal is Mike, I cant let my brother in law out run me with his 68 Z especially when he is running one of my old small blocks in his car. :mad: I sold my race car and I'm done with that for now, but I still enjoy going to the track ever now and then and playing a little. I just want the car to run to its full potential, but first and fore most it is just a driver. one of these years i will restore it and maybe if I'm real lucky it will turn out as nice as your 69. graemlins/beers.gif

Loser buys the beer tongue.gif

I drink Mich Light and I like it cold! graemlins/beers.gif

Problems with solid roller cam longevity in street engines is NOT a myth. If you plan on trying a solid roller cam on the street there are a few that have had success with the Crower severe duty lifters and Isky tool room valve springs. Most are replacing lifters and/or springs every couple seasons. Idling extended periods of time seems to be what kills solid roller lifters.

A solid roller isn't something that I would consider right now. Although nothing sounds sweeter than hearing one through mufflers, it's just not for me. When I freshened the 396 I just wanted to keep it stock for the most part and very drivable. I had thougt about putting 1.88 exhaust valves in the heads, but then desided to leave the heads alone as they are original to the car and aside from a light surfacing untouched. I would just like to pick up a couple of tenths and I think Oger has a valid point about my converter not being the best one for the job. I have thought about puting the 4-speed back into the car, but then I start remembering all those broken parts and inconsistant shifts I quikly deside againt that.
Thanks to all for the help and for the ideas and please keep them coming
Nick

o.k first off, i don't want to start the old "solid roller vs. reliability" debate up, but i must add my .02 concerning longevity/reliability (i just can't help myself ;) ). myself, and several of my buddies have run and are running solid rollers in our cars. nobody has yet had a failure in lifters or anything else but springs for that matter, and no more than 1 or 2 spring issues, and that was just from tempting fate with substandard springs. the key is just good parts. you don't "hafta" run tool room springs, but they are nice, and quality lfters as well. three of us are running comp cams lifters, and i'm running isky springs, one step down from the tool room springs, manley pushrods, and an isky cam. this is my second season of running all of it, tons of street mileage, probably more idling than anything, and never a problem, and the lash is always close or right on. another buddy ran his 406 and solid roller set up, nothing exotic, for about four years, many street miles, and never had to touch a thing. most of these are smallblocks, from 355 to 408. but i also know a couple of my buddies w/ bigblocks ran the same cam and lifters for several years, and never had one let go. it also really depends on lift and general agressiveness of the cam, but most of these cams i'm referring to are around .600-.650 lift and decent duration. mines little, only around .610, and .250 @.050 . so in short (yeah right :rolleyes: ), would i reccomend it for a daily driver, not likely. would i reccomend it for a serious street or street/strip car? hell yes! and there are no unsightly cam break in problems, either. just buy the best parts you can afford, and rev on! graemlins/thumbsup.gif

Where are you guys getting this DCR calculation? This calculation takes cam duration into account when figuring compression?

lluciano77, if you really wanna know, check out my work. It explains DCR and how the DCR calculators work.

http://www.eden.rutgers.edu/~vath/327/DCR1.jpg
http://www.eden.rutgers.edu/~vath/327/DCR2.jpg

Most of the pure stock drags are at between 800 to 1000' elevation. They are running the cams 6 degrees retarded, which genrally picks up 2 tenths and 2 mph. Run your initial at about 18 degrees and all in by 3000 rpm for a total of 38 degrees. Try 68 jets in the front and 78 in the back with a yellow spring. Plug the back power valve. You should be able to spin the tires as long as you want.... if you want! But we generally don't like to. graemlins/clonk.gif
Peter