It would be interesting to see someone do a dyno comparison,with as cast Dart and AFR, then after blending to see what the HP gain would be in just improving the heads, low lift numbers seem to be very important since the valve is at any given number besides peak, twice.
Low lift numbers are important if the first few hundred thou of lift represent a large percentage of your total lift like on a head like this. You'd have no reaosn to run a .750+ lift cam with this head, but on a head where you're looking for peak flow numbers and are looking at .800+ lift, low lift numbers are far less important than getting those upper lift numbers. Also, the valve may see those low lift numbers twice, but if you consider how fast it's accelerating through those numbers, it's really not that important as compared to the amount of time it spends between .500 to max lift and back to .500 again.Originally Posted by Jspeeddemon
In the madness of this world, know the Peace of God.
Here are a few pics of the finished chamber.
In the madness of this world, know the Peace of God.
bore relief
Steel, how much difference does a bore relief notch make, where the combustion chamber hangs over the deck, on a 4.310 bore? I used to see this a lot, but I just have not noticed it lately. Just wondering if anybody has tried to flow test with a notched bore.
Thanks,
Chris
Great question. It's something I want to test one day when I have time. Most aftermarket heads today have chambers sized for a 4.500 bore and setting them on a 4.25/4.31 bore definitely effects flow. How much I couldn't say. Notching the cylinder would definitely make a difference.
In the madness of this world, know the Peace of God.
I never hang out in this forum anymore because it lacks diversity in opinions and the loudest are often wrong. However, I saw this same thread over on Yellow Bullet (a real good source for solid tech info if you're interested) and figured it would be here as well. FWIW Tony Mamo, owner of AFR offered this perspective:
Guys,
Scott posted the same exact thread on two other boards. I took the time to respond on one of them.
The abridged version of my response is AFR stands behind the product we manufacture. We offer a lifetime warranty and we stand behind our advertised flow numbers as well.
If you have an issue with the quality or airflow of any of our product we suggest you contact us directly so we can address your concerns. If we get the product back and it doesn't flow we will do what it takes to make sure it does as well as reimburse you for all your freight expense.
Rick, the President of AFR, contacted Scott on my behalf. He encouraged Scott to give us an opportunity to evaluate the heads ourselves. We are only a day away via UPS and would naturally like the opportunity to flow test/look over the heads and rectify the situation should there be a need.
The folks that deal with us on a regular basis (both individuals and shops) know we really care and take pride in everything we produce. We do our best to advertise real world production numbers....not prototype or best case scenario. Alot of shops and individuals have seen our heads meet and exceed what we advertise....but keep in mind there are a ton of variables here.
The best we can do now is flow test a production 305 piece off the floor unless Scott decides to send us the heads in question. If he does I will post the results from our flowbench and fill you in on how we handled the outcome of this situation one way or the other
Thanks,
Tony ,
AFR offered to take the heads back, flow them and do whatever it took to make sure they met advertised numbers AT NO CHARGE. He chose to pass on this free offer due to schedule (which I get) but to be clear, AFR would have done whatever necessary to make sure the heads did flow advertised rates.
I'll admit to being biased towards AFR (Dart & Brodix too) and think it sucks when someone bags on a product/service on websites without even giving them the chance to make it right EVEN AFTER THEY OFFERED. I bet Foxwell Motorsports wouldn't take kindly to the same thing happening to them.
Friends, while not the popular opinion here (but is in larger racing circles), there's nothing at all with assembled heads. I've run dozens of sets over a lifetime of racing (currently running AFR's though I rebuilt these after a different PB "expert" boned me on them). I do agree you need to take them apart, check springs, guides and valve job, etc but rarely have I had to do much to them to make them "right".
My point is, if you got a problem with a supplier's parts/services, at least have the decency to give them a chance make it right before posting on a bunch of websites saying how much they suck.....
Oh for those interested, the YB thread is here AFR/Dart flow comparisons, out of the box. - Yellow Bullet Forums You might have to be a member to check it out, not certain. It's closed now due to some of Scott's fans becoming unruly but the first few pages are interesting.
Peace out.....
just for clarification?????
Tony Mamo doesn't own AFR, Rick Sperling does. IF FACT if you took the time to read your own post you would know that. But thats always been your problem David, you into it what you want it to say, not what is actually says. So your opening statement holds true, the loudest are usually wrong.
I have all the respect in the world for Tony, and the 4 sets of heads I have to chose from on my shelf, I feel the AFRs are the strongest performers to date.
But I am not sure exactly what you expected him to say. I can't quit figure if your still pissy over the hea ds that were selected for the 5000 RPM offshore boat that were better suited to a alky drag motor of the same size, or the eye thumbing you took over the v-drive gear rotation. Which ever.
I wonder if Mamo would be willing to flow test the heads Steel just finished against a set off the self. I doubt it, Tony is sharper than that. You on the other hand, not so sure.
If people like to talk about the varibles of a dyno and the operator, flow benches are in a world of their own in theat regard. They have dynos beat hand down in questionable data bench to bench, operater to operater, and even day to day depending on the baro. pressure.
But you just couldn't resist could you David. Your more worried about what Steel posted on a set of heads, when you should be worrying more about the fact that you have been running RH gears in a LH application, and NOW wonder if if its OK to switch to the correct rotation
When you have the gear rotation thing down pat, maybe then you should venture into a area you know zero about.
Last edited by gn7; 09-12-2011 at 06:06 PM.
fun stuff
well, the problem with these fun threads, is that everyone reads into them a little different. im no better than most at that. i talk with Scott often, and have about this deal here. i believe his intentions were to simply show people that even some of the best heads should be checked out. in fact, most will not be right, out of the box. they might work great, but they wont be near their best.
when i asked him what he thought about AFR heads, he said he really liked them, may have even said he loves them. i dont think any of this was meant to bash AFR or anyone else. from what he tells me they make a fine product. people are quick to get side tracked from whats being offered here. im pretty sure, regardless of all this, if you asked him what heads he recommends, AFR is still a top choice.
i can understand AFR's response, and its admirable that they would stand behind their product. for that reason, i may make make my next heads AFR's. i wish some other head makers had the same commitment to quality. i dont think for a second, this was meant to throw AFR into the Pro Comp pilejust to show some real world info, to allow people to make better choices about what they may want to do to their heads before bolting them on.
if i were to buy AFR or any other head, they would go straight to my favorite cylinder head shop to get done up. its very common knowledge these days, that you dont run a set of heads straight out of the box, and expect perfection, or anything real close.
maybe knowing more about this helps me understand it all, and i know a lot of people here are smart enough to understand it for what it is. my personal opinion is this: AFR makes nice heads, send them to a good head guy, and make them real nice.
X2 A good tailored suit vs off the rack fitwell, the problem with these fun threads, is that everyone reads into them a little different. im no better than most at that. i talk with Scott often, and have about this deal here. i believe his intentions were to simply show people that even some of the best heads should be checked out. in fact, most will not be right, out of the box. they might work great, but they wont be near their best.
when i asked him what he thought about AFR heads, he said he really liked them, may have even said he loves them. i dont think any of this was meant to bash AFR or anyone else. from what he tells me they make a fine product. people are quick to get side tracked from whats being offered here. im pretty sure, regardless of all this, if you asked him what heads he recommends, AFR is still a top choice.
i can understand AFR's response, and its admirable that they would stand behind their product. for that reason, i may make make my next heads AFR's. i wish some other head makers had the same commitment to quality. i dont think for a second, this was meant to throw AFR into the Pro Comp pile
if i were to buy AFR or any other head, they would go straight to my favorite cylinder head shop to get done up. its very common knowledge these days, that you dont run a set of heads straight out of the box, and expect perfection, or anything real close.
maybe knowing more about this helps me understand it all, and i know a lot of people here are smart enough to understand it for what it is. my personal opinion is this: AFR makes nice heads, send them to a good head guy, and make them real nice.
David, I'm going to put the essence of your entire post in genuine perspective with one simple question. Can you quote, copy, point to, or even suggest anywhere where I even remotely said AFR's parts or service sucks?
In fact, I can show you the exact opposite.
Maybe you should get ALL the facts straight before you do your own "bashing". Foxwell Motorsports fixed these heads for the customer at no cost, and at the request of the customer. Like I stated on the other sites...my obligation is not to AFR, or the "internet experts"...it's to my customers. Period.
Everyone seems to forget this was a comparison, and AFR wasn't the only one mentioned, but I'll be damned if I'm going to follow up any further on this publically.
In the madness of this world, know the Peace of God.
Thanks Nelson, you pretty much hit the nail on the head. I guess I was a little naive in thinking the thread would be seen objectively by more than just a few. Definitely my bad.well, the problem with these fun threads, is that everyone reads into them a little different. im no better than most at that. i talk with Scott often, and have about this deal here. i believe his intentions were to simply show people that even some of the best heads should be checked out. in fact, most will not be right, out of the box. they might work great, but they wont be near their best.
when i asked him what he thought about AFR heads, he said he really liked them, may have even said he loves them. i dont think any of this was meant to bash AFR or anyone else. from what he tells me they make a fine product. people are quick to get side tracked from whats being offered here. im pretty sure, regardless of all this, if you asked him what heads he recommends, AFR is still a top choice.
i can understand AFR's response, and its admirable that they would stand behind their product. for that reason, i may make make my next heads AFR's. i wish some other head makers had the same commitment to quality. i dont think for a second, this was meant to throw AFR into the Pro Comp pile
if i were to buy AFR or any other head, they would go straight to my favorite cylinder head shop to get done up. its very common knowledge these days, that you dont run a set of heads straight out of the box, and expect perfection, or anything real close.
maybe knowing more about this helps me understand it all, and i know a lot of people here are smart enough to understand it for what it is. my personal opinion is this: AFR makes nice heads, send them to a good head guy, and make them real nice.
In the madness of this world, know the Peace of God.
could you please clarify all this???
the answer to this should be pretty obvious by now. not gonna happen.
DAVID
You shoud know by now that if it was not spec'd by one and built by the other, then it can not possibly be CORRECT. Makes one wonder how Anderson, Brogdon, Krisher, Stanfield, and the rest of the boys do so well without their esteemed knowledge. A cure for cancer, and the ability to walk on water are forth coming, stay tuned.
Last edited by Bubbletop409; 09-13-2011 at 11:33 AM.
Larry
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