Hey guys, heard about you from a friend who said there's some awesome background knowledge here for buildups so hope you dont mind a 3rd gen fbody owner coming by for some help.

I have a 2bolt 406 with stock rods, Manley forged flattop pistons and a stock aftermarket nodular crank. I also will be using 1 3/4" headers with a single 3" exhaust. This is going in a 91 camaro with the stock 700R4, converter,3.42 gears and 26" tires. The car weighs 3200lbs dry.

I'm looking at AFR 190's at least. But am starting to think 210's would be a better match. Only consideration is that this will be a street car(in summer only of course) also for the next couple of years also probably.

I love a lumpy idle but don't want to get into using a pump so I'm looking for something that will give me the highest avg figures really. I dont' care about peaks as much as higher avg's for a rev range of about 3000-5500 which will be my ultimate redline.

With my little knowledge and Desktop dyno I've found the XR276 cam to look good with AFR 190's so far. What do you guys think?

As silly as this sounds, I suggest either a good old CC 270S or maybe even a 282S solid cam OR one of Harold's great solid cams that fall in the grunt motor rpm operating range you are talking about!!

Don't get me wrong here b/c I know guy's spec. different LCA's and ICA's as well as lifts and such to gain off corner power but I DO feel these two type cams should put you in the ballpark!!

AND I do figure Harold can pick one a lot better thyen I can for your specific wants...

pdq67

I've heard of this cam wizard named Harold and noticed a few of his posts here. Would love to hear a suggestion and have some contact info for your business Harold graemlins/thumbsup.gif

With that low of a redline, 190's or 195's would be your best bet, IMO. Torque is what you're going to want with the drivetrain you have. With the stock rods on that 400, keeping the revs down would be a good idea. On the cam side of things, keep in mind that it's better to err on the conservative side, especially with your combo. I would consult UDHarold, or any of the major cam manufacturers after you have the heads set in stone.

Well one thing you said in your question, and the term "road race" would lead me to a wider lsa cam. Likely a 112 lsa. The power wont be as peaky in the middle, but will reach up a bit longer. Probably right where you want to be. And the 112 lsa will give you a bit smoother idle. So at least keep a slightly wide lsa in the specs, I would think. And about 278-285 seat duration in a solid cam or 270-280 in a hyd cam.

If you wont be spinning this 400 north of 6000, and you probably shouldn't, I would use a hyd grind.

http://www.cranecams.com/?show=browseParts&lvl=3&prt=5&Vehicle_Type=Auto&Cylinders=8&Engine_Make=CHEVROLET&Year=1973&Engine_Size=262-400%20C.I.&partNumber=119831&partType=camshaft

Rega
AFR does not make the 190 any longer, it has been dropped.
If you are going to keep the RPM that low, I agree the 195 would be your best bet.
They have 180, 195 & 210.
Also the full competition ported models of these heads.
For info, with the 76cc head & flattops you are going to be about 9.7 assuming the deck isn't cut more than .005 or so.
If you email me I can probably save you a few dollars on the AFR's ;)

If you wont be spinning this 400 north of 6000, and you probably shouldn't, I would use a hyd grindAs long as the motor still is using the stock rods, which will be for a couple years at least, I won't be spinning past 5500.

Can you give me a little more detail on why I should use a hyd setup over solid for under 6000? Faster ramp rates?

For info, with the 76cc head & flattops you are going to be about 9.7 assuming the deck isn't cut more than .005 or so.
If you email me I can probably save you a few dollars on the AFR'sEmail on its way graemlins/thumbsup.gif

And see, I look at the head choice totally different from most of you. I feel that at least a 210 or 220cc intake and 2.05 or 2.08 valves would be more ideal. The reason is because the BIGGEST SB port is still smaller than the SMALLEST BB oval port. I don't think that anyone will argue that a healthy 396-402 with oval ports will dyno higher than an equivelant SB. And the number one reason for this is because of the better flow characteristics of BB heads. Even though a 406 is a SB, 400 cubic inches is still 400 cubic inches, regardless of whether it is in the form of a SB or BB. If a SB is expected to produce the HP/torque numbers of a BB, then it also needs to be able to breathe like a BB. That requires ports and valves which will allow it to do so. And also, to take advantage of the breathing ability of bigger ports/valves, the best (and I agree, the most expensive) cam choice would be a roller. In an engine that will be kept UNDER 5500-6000, a hyd roller would be just fine. Otherwise, if the choice is a flat tappet cam, then something in the range of a .510 to .540 lift hyd will work (you can certainly use a solid if you like). When you get bigger than a .510 lift in a SB, then you need to start considering a bigger spring (stock SB spring pockets are 1.25, the next step up is 1.45). Opening up spring pockets in SB heads needs to be done VERY carefully because of the possibility of going into a water passage. This is normally NOT a problem with the better aftermarket iron heads (Dart-World). A healthy SB400 can easily handle a .510 to .550 lift and a duration @.050 of 240 to 250. EASY! In a SB, it is more critical to check valve-to-piston clearance when you get into the .500+ lift range.
In something like a late Camaro, space restrictions kind of limit you to staying with a SB. But keep this in mind, when building a REALLY strong SB, you can get into BB expenses real quick. I love SB400s, I've built a lot over the years. But I am the very first to say that if you REALLY want the BIG HP/torque numbers, spend your money on a BB!!!

One reason the BBC ports have a larger volume is that they are longer. The the difference in cross-sectional area isn't as much as the volume leads one to believe.

Originally posted by onovakind67:
One reason the BBC ports have a larger volume is that they are longer. The the difference in cross-sectional area isn't as much as the volume leads one to believe. Ditto ;)
Port volume is a very good indicator of cylinder heads of the same family but you cannot compare different types. Even 23 deg vs 18 deg will skew the results as cross sectional area is the important number in port size.
If the port is too big it can flow killer brag about sewer pipe numbers but it will be a complete dog on the engine.
It may make the same peak power but everything else will probably be ugly
The way I understand it you want enough port in area to support the rpm you want to run at with the size of the cylinder you have & the type of cam. A roller will normally take a slightly smaller port for the same rpm than a flat tappet because the cylinder sees the port effeciently for a longer period time

Cam Wizard, eh?
For the RPM band that you're looking for, you don't need a big cam,
Most of the guys here have heard of my daughter's 'Going To The 10th Grade' car, an '84 Berlinetta Camaro with a 383 SBC, using the 195AFR heads. It had Hookers, a Performer manifold(pre RPM days..), and an UltraDyne 266/276H12 cam, 211/221 at .050, .471/.485 valve lift with Crane 1.6s, and a 112 LSA.
It idled smoothly at 400 rpm, but would cause the oil light to come on, so I moved the idle up to 550.
I would use the 195AFRs, they are excellent heads for a TORQUEY 406.
If you want a reliable, low- or no-maintenance solid lifter cam, I can make you a single pattern 264 at .020, 232 at .050, .470" lift with 1.5s(.501" lift with 1.6s), and 112 LSA. This cam should idle at 750 or lower, and have massive, flat, torque from 1500 to 5500. You would need to adjust the valves about once a year.
For a hydraulic, I have a 276H14, 221 at .050, .454" valve lift, and 114 LSA. We use this a lot in oval track racing where they have a 17" vacuum rule. The 276 was the exhaust lobe on my daughter's 383, and it ran for 8 years as a daily driver.....
Just some suggestions....

UDHarold

Thx for all the info guys. Picking up alot.
Still a little confused on how much duration and lift I can get away with using AFR's 1.25" springs. I really would like to go near the limit of what's reliable for city driving and idle. I'll be using 1.5 roller rockers to start off and thinking in a couple years i'll goto 1.6's with larger springs.
So, why not something like 232 @ .50 and just over .500 lift(but below .510) with a HYD grind? I don't necessarily need low maintenance... I like having something to watch and work on. I dont' even mind visiting the gas station. I just don't want something my brakes won't work with really. Is LSA my only significant consideration for most of this and how much can I really get away with? Less than 112? 110?

I want a bigger cam but I'm not sure if I'm just being the typical guy who thinks he needs more cam than he does, or if I need better hardware to run it reliably or if you guys are just suggesting the more friendly camshafts.

Hope I'm not asking too much at once but I'd really like to understand exactly what I'm putting in, where it's working and when.

oh, I have decided on the AFR 195's I should say.

The heads come standard with a 1.450 hyd spring, 120 seat pressure.
They can be ordered with just about anything you need ;)

The 5500 rpm limit is why your being recommended small cams.
Your stock rods are the limiting factor in your combo.

You have heard from the Man!!

Harold, grind him up one of them explosive up to 5700 cams that then falls right on it's nose just like the roundy-round guy's use coming outta the corner heading down the long straight to the other corner!! Don't they want their cam to fall right on its nose just as they hit the brakes to enter the corner???

And if he runs outta rpm on a road course, he just needs ta have more gears to keep her operating in the right rpm/speed ranmge, imho... Can you say, five-speed??

If the sucker is geared and tired right, it will be a hoot!!! As alway's, jmho..

I've chatted several times with Harold in the past about small SB solid cams that create great street rpm range grunt... He has at least three what I would call a family that caught my eye once he let me know they existed as far as being nice small solid cams!!!! Which, imho as a cam layman is FANTASTIC!!!

Small solid cams are kinda hard to find in this day of BIB crap!!

Please listen to the MAN!!!

pdq67