Thread: Cam Suggestions

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Guys, my insterests have changed. Not really wanting to drag race anymore, just have a good, dependable street car and I need to swap my cam shafts around to do this. SO.....

My engine:
377Cid(400block, aftermarket crank, steel rods, forged pistons)
full roller valvetrain for solid camshaft
441 Casting cylinder heads (76cc Combustion chambers)
I have a torker II Intake, but i don't HAVE to run it, i can change that.
No carburetor yet.

I'm not looking for a daily driver or a fire breathing dragon, but something in between. A powertrain that I can depend on, one that makes good vacuum, and that doesn't require higher than 93 octane gasoline to run. Something around 350-400 horse would be good enough. Thanks in advance for any help that you can give me and any recommendations that you have.

I would build this combination with your 377:

www.airflowresearch.com/eliminator.php

You could always drop down a cam size and still have plenty of power if you wanted it to be a little more street friendly.

I'm trying to use my old iron 441 casting heads if i can because of financial reasons. I'm doing everything I can to keep from having to sell this motor to pay for school.

If this sounds like the most horrible idea in the world, could you guys also recommend a good BUDGET set of cylinder heads? I just can't afford a high dollar set of heads right now.

A setup that would give 1HP:1CID would be perfect.

Call one of the cam company tech lines, see what they recomend... These guys build cams for a living and can usually come up with a cam for most any application....

I run a 406sbc, 8.5-1 dished pistons, rebuilt factory rods and crank, ARP, #450 heads ( '77-'80 305 heads that were ball milled to open up behide the 2.02 valves, 58cc, UD cam 276/286 at .0045", 221/230 at .050", .454"/.454" valve lift, and 110 LSA (healthy lop ), GM dual plane Q-jet manifold, redrilled Q-jet, and headers. I run 36 total timing, 87 octang, no knock, or over heating with 6cyl rad, t350/shift kit, high 3's rear-end.
Mines not a a fire breathing dragon, but it is in a daily driven '68 El Camino, 20 miles to work every day. 100+ to -30, sun, rain, or 15" of snow.

What is it in, what is the cam? your mpg won't go up over 12-14 mpg even if you neuter it!


Pat

this motor is going into a 1972 el camino with a th350 and about a 3.55 rear end gear. About 10-11 mpg is all i'm asking for. I just can't stand driving a car that gets 2-3.

Originally Posted by Hopper111

Guys, my insterests have changed. Not really wanting to drag race anymore, just have a good, dependable street car and I need to swap my cam shafts around to do this. SO.....

My engine:
377Cid(400block, aftermarket crank, steel rods, forged pistons)
full roller valvetrain for solid camshaft
441 Casting cylinder heads (76cc Combustion chambers)
I have a torker II Intake, but i don't HAVE to run it, i can change that.
No carburetor yet.

I'm not looking for a daily driver or a fire breathing dragon, but something in between. A powertrain that I can depend on, one that makes good vacuum, and that doesn't require higher than 93 octane gasoline to run. Something around 350-400 horse would be good enough. Thanks in advance for any help that you can give me and any recommendations that you have.

What is you current comp. ratio??

441 heads are great for what you're doing. 993 are evn a touch better. I am running a van with an RV conversion (higher deck height etc) It weighs 7000 ibs with 1 occupant and 57 gallons of fuel. Engine is a std bore 350. Cam, has .447 lift intake, 461 exhaust, stock rockers, Edelbrock performer (2101) single exhaust @ 2.75 exhaust. Monolithic convertor and stock muffler designed for high altitude. I just pulled a trailer weighing 7,000 lb up to and back from Denver. I forgot to mention, I was loaded inside the van with gear and travel stuff and an extra passenger. Got 16 mpg average, worse being 13 mpg on the huge grades they have there. Engine dyno'd @ 330 hp, 411 ft lbs trq 5 years ago. We put it on the floor dyno and with 2.73 rear gears, it laid down 265 hp and 320 ft lbs of torque. You have way more then enough potential to achieve what you want. Keep it simple and you will get it. By the way, the engine now has 350,000 miles on it and just started getting a bit of blow by. Remember the mpg I just gave you? it's real and I can't complain even at 3.00 dollars a gallon (87 octane)

Erik, with a 4.155 bore, a flat top piston and a 76 cc head, I think my compresion ratio will be around 9.5:1. I don't really know how to calculate compression exactly but that is what the book that I ordered those pistons out of.

I got the 441 heads off of the old 350 that came out of the el camino. The valve springs are tired and the heads probably could use a surfacing and a set of guides, but i think i'll still get away cheaper than going out and buying a high dollar set of big chambered heads.

I'm looking for like an economized street car I guess. One that will make 350-400 horse and get around 12 mpg so that I can jump in it whenever I'm feeling froggy and run around town with it instead of my ol' pickup truck.

Originally Posted by Hopper111

Erik, with a 4.155 bore, a flat top piston and a 76 cc head, I think my compresion ratio will be around 9.5:1. I don't really know how to calculate compression exactly but that is what the book that I ordered those pistons out of.

I got the 441 heads off of the old 350 that came out of the el camino. The valve springs are tired and the heads probably could use a surfacing and a set of guides, but i think i'll still get away cheaper than going out and buying a high dollar set of big chambered heads.

I'm looking for like an economized street car I guess. One that will make 350-400 horse and get around 12 mpg so that I can jump in it whenever I'm feeling froggy and run around town with it instead of my ol' pickup truck.

I would look at cams that have around 220 at .050.
I would try and run 8to 10 degree's more duration on the exhaust side

This might be a stupid question, especially coming from someone who has been assembling engines of all makes and models for the last two years, but i never though to ask. What does duration do/effect exactly?

Duration is rated as either advertised or actual time off of the seat that the valve "sees". Advertised is the most used to sell the cam. Effective is mostly rated for effective use for flow numbers. I have seen manufacturers like Comp Cams use .020 (which is very useful for Race Motors). Your cam card and the people you talk to will use the .050 spec for an effective duration. It is widely known that the valve (especially intake) does not start to react to proper flow until it lifts itself off of the seat and it reaches this spec. .020 is useful and .050 is useful for degreeing the cam because of ramp speed and a lot of heads really do offer a flow that's effective at that start point. You can have a cam rated at .294 duration but doesn't start to do it's job until the valve raises off at .050 therefore you should consider that duration spec not advertised. Others can do a more effective job coming right off the seat at .020 or 010. It's experience and understanding designs of the profile to get your combo just right for your engine. This also helps you understand where to place centerlines etc, when degreeing this piece.

Ok so after reading the last few posts about duration, it would seem that I should be looking for a low duration, low lift cam. As Erik said 220. The cam I already have is 242/242 @ .050", So 220 would bring my opening RPM down by about 1000 RPM.

My cam requires 3000+ stall @ 242 duration, would that mean that a cam with a 220 duration would require 2000?

If so, what is stock stall speed for most factory th350 torque converters?

Does duration affect performance more, less, or the same as valve lift?

so what kinda milage and performance do you get out of that cam?

There are 2 cams that I've been looking at.

1 is: Upper low-end to mid-range torque and power. Daily performer, mild bracket.

RPM Range: 1200-6200
Advertised Duration: 280/287
Duration @ .050: 242/251
Lift: .502/.502
Lobe Center: 110c
The other is about .484/.484" lift, but I can't remember the duration.

Would the above cam (.502/.502") be a big step down from my cam at:

Intended for hot street/strip applications. 3000+ stall or manual a must.

RPM Range: 2500-6500
Advertised Duration: 285/285
Duration @ .050: 242/242
Lift: .567/.567
I'm having a bit of a problem finding solid roller camshafts with lower duration and less than .500" lift.
Lobe Center: 110c

Good job Denny. After that previous post, there shall be not one thing understood about cam selection or proper set up. I know a lot of builders would have glazed over, but if anyone really wants more understanding and knowledge about the subject that does it readily. Great job once again.