Help me decide between these heads

I agree with AFR over elderbrock and also agree with the statements that you have other heads out there that will not only outperform but also not limit your HP upgrade.

I put some obscure Australian heads which went through a 5 axis CNC porting (secret recipe) and can easily bet that the combo can't be outflowed by any CNC ported heads with a <220CC runner. I slapped those babies with a more then descent cam and dyno'ed at 550HP naturally aspirated.

With good V8 heads 750cfm carb a plus, with great V8 heads a must..... and would consider 850cfm.

AFR185s - dont bother with 165s on a 351w.

You will want a little more agressive cam than the RPM cam with 185heads. If you go that route, you will never look back. You should be making 350hp to the wheels with that combo...and a better carb

Heh I just went thru what your about to go thru. I am running TFW heads, and the stage 1 cam. The rest is in my sig. I am building the engine this week, and I will let you know how it comes out. I got my block yesterday .

As far as the carb goes, I would go with a street avenger 670cfm. I did a lot of research on this, (see my thread: Spacers, are they worth it ?) and a lot of good info came to me. Also I emailed engine builders, and talked to local builders, and heh even got the famous carb calculater...remeber on a 351ci engine, at 5000 rpm shift point, your cfm is 502..according to the calc. so with that in mind, going to big on the carb could not net as much performance as you want. I spoke with some people who run a 670, and they were very happy with it. Much as D Hearnes said in our own forums. Snappy throttle response, but was also able to dig out the power.

I will give a very detail blow by blow report hopefully this weekend with pics !

I wouldn't be afraid at all to run any of those heads, RPM's, AFR165's or Canfields. You've really got to ask yourself where you want the motor to make power. Do you want it in the low to midrange or midrange to topend ? Low to midrange is easier to live with on the street and will move the car off the line faster, also easier on the motor's rotating assembly and block. ( it'll last longer) Mid to upper rpms ? Well let's just say that on the street, unless you've got some really steep gears and a 4 or 5 speed manual trans, you're not going to see those rpm's very often ( unless you like to visit with the local law a lot) Also harder on the motor's bottom end, taching 6-7 grand frequently. Bigger cams, single plane intakes, big carbs and big heads all move the range that the engine likes to operate best up the rpm scale.

Depending on the cam and intake, I would also consider the AFR 205

before all of this discussion of heads.....

Were you considering Piston to Valve clearance as an issue? Hence the 1.90 intake valve? If that is the case, then what we are saying about 2.02s and 2.05s.....may be useless info.

allcarfan said:

before all of this discussion of heads.....

Were you considering Piston to Valve clearance as an issue? Hence the 1.90 intake valve? If that is the case, then what we are saying about 2.02s and 2.05s.....may be useless info.

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Good point. I know on my old block, I could not fit 2.02 heads with the pistons.

Here are a few of my thoughts.take them for what you will.

1) By FAR, and I do mean BY FAR the BEST VALUE in heads is Canfield 192, period. They will support in excess of 500 hp in stock form, and can be ported to flow really well. How can you beat $1195 assembled with FERREA Comp valves?????? AFR 205 are $1700 PLUS!!!!!

2) Edelbrock RPM do pretty damn good against AFR 165 in the head tests I have seen.....good enough to really make you say why the price difference???? Eddies are about $1000.00 AFR 165 is $1325.00.

3) There was a really good article I read recently where they tested a bunch of diffrent size carbs on a big block mopar.......Shattered all the myths about carb sizes......Guess what: when TUNED, the bigger the carb, the more hp AND torque they made.......interesting. I think a 750 is bare minimun for a 351ci engine, you just need to tune it so it is running proper air to fuel.

4) Lastly........I hope those are not factory CAST pistons? I hope they are forged. It really is not the best idea to throw high dollar heads and radical cams and whatnot at a stock, tired bottom end, unless of course, you enjoy rebuilding engines and ruining heads.

My 2 cents.

67GTCOUPE said:

Here are a few of my thoughts.take them for what you will.

1) By FAR, and I do mean BY FAR the BEST VALUE in heads is Canfield 192, period. They will support in excess of 500 hp in stock form, and can be ported to flow really well. How can you beat $1195 assembled with FERREA Comp valves?????? AFR 205 are $1700 PLUS!!!!!

2) Edelbrock RPM do pretty damn good against AFR 165 in the head tests I have seen.....good enough to really make you say why the price difference???? Eddies are about $1000.00 AFR 165 is $1325.00.

My 2 cents.

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Actually I saw a very good article on flow for heads, and the ones who came out on top and not mention here were The Trick Flow Twisted Wedges..All tests were done with a mighty demon carb 750. very interesting read that was.

Victor Jr.'s, best bang for the buck head out there. Be ready to notch the pistons though.

I am running the RPM 1.90s on a 10.5:1 395 stroker. I am also using the entire RPM package escept for the carb, which is a Holley 750. The package runs really strong. This combo seems to complement the horsepower with a pretty decent torque curve, and torque is what gets you moving. I love the package.

That article mentioned about carb sizes waqs written by david Vizard for PHR magazine. It was a very good article. I think that whole mathematical formula for carb sizing is bunk anyway. While it can mathematically can tell you what cfm you need for a given rpm, it never takes into account the rate of acceleration, which is what we are after anyway. Crusing at 5000 rpm may only require 500cfm, but getting there fastest may be an entirely different story.

Max Power said:

I am running the RPM 1.90s on a 10.5:1 395 stroker. I am also using the entire RPM package escept for the carb, which is a Holley 750. The package runs really strong. This combo seems to complement the horsepower with a pretty decent torque curve, and torque is what gets you moving. I love the package.

That article mentioned about carb sizes waqs written by david Vizard for PHR magazine. It was a very good article. I think that whole mathematical formula for carb sizing is bunk anyway. While it can mathematically can tell you what cfm you need for a given rpm, it never takes into account the rate of acceleration, which is what we are after anyway. Crusing at 5000 rpm may only require 500cfm, but getting there fastest may be an entirely different story.

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I ran the edelbrock rpm heads and intake on a 351w..was VERY impressed! BUT, my custom cam grinder (Jay Allen) worked the numbers.....Vic Jr intake was worth an average of 30hp across the board, and the heads would choke it REALLY bad.........so I decided to cancel my vic jr heads I ordered, and get Canfield 192s instead after he worked more numbers and got me another 25-30hp over a wide range by ordering the Canfields with 54cc chambers.

Anyway, the bottom end needs to be strong and sound, regardless of what heads you choose.......my 2 cents.

Both are good heads but the AFR 185 is definately a better head than the Edelbrock.
Kevin

Sicarius428 said:

Both are good heads but the AFR 185 is definately a better head than the Edelbrock.
Kevin

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when I was looking to get my Edelbrock RPM Performers ported and polished, I contacted a shop that does CNC machining and asked about getting my heads worked up. the owner told me it would be cheaper to get new AFRs than it would be to port my heads. Also, he said that his own dyno results show that on the same engine, the AFR heads made 30 more peak hp than the edelbrocks did, all other things being equal. Kinda makes me wish I had........

Sicarius428 said:

Both are good heads but the AFR 185 is definately a better head than the Edelbrock.
Kevin

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As far as I know, the comparison was between the AFR 165 and Edelbrock. That is a fair comp, puttin g 185 fully ported heads against unported 170cc heads isn't.

The 185 will flow more than stock Eddies, no doubt. The 165s.....well, probably flow more, not much, but really is it worth the $325.00 premium????

Then the Canfield 192s will hold their own against the AFR 185s and power wise, won't be too far behind AFR 205s.