cyphur

iTrader: (10)

i couldn't explain it to you if i tried, but you need to read J-Rod's thread on timing and such. VERY interesting read, if you can digest it all. it basically says every motor combo has an optimal timing point, and that more isn't necessarily good.

Bo White

iTrader: (59)

Timing is just that, timing. Every engine has its "best" timing; and the lower the amount of timing for maximum power- the better the combustion chamber shape is in that head. The more efficient the chamber- the less timing it requires to properly fire the mixture to make maximum power. This doesnt mean that a cylinder head that requires more timing than another will not make more power than the other.

Ed Curtis

The cure for timing your engine for maximum power...



http://www.msdignition.com/ignition_23_7531.htm

Ed

J-Rod

Good fast burn chambers don't need timing. Older poorer design chambers need more timing to get he chamber charge burned in time...

Props on your heads Visceral.

I'm not being ugly here to TEA, Visceral, or anyone else, so PLEASE do not take it as such.

TEA's bench is not a Superflow 600 or a Superflow 1020. The 600 is what you see "most" shops use. We can all sit around and say that all benches should be the same, but the reality of the situation is even within the same mfg (say Superflow) there are variances between benches. When you move between mfgs. there are even greater variances in many cases.

TEA has pointed out their bench is certified by NIST, etc... My point of this is that the only real use of those numbers is from a delta standpoint. In other words the differnece from what they did stock to what they do now.

To compare TEAs numbers on thier bench to Tony's numbers on a Superflow 600 is an erroneous way to do a comparison. Flow numbers are simply one part of the overall performance of a motor.

I'll agree just with Andy. I've seen a set of heads that flowed better than another set of heads. But, once you bolted them on, the lower flowing heads made 30-40 MORE hp. I'm not saying this is always the case. What I'm saying is there is a lot more to good heads than just flow numbers.

I know I've harped on port volume, velocity, etc... I just want folks to understand that before you jump all over this post and only look at the raw data , you need to understand that there are more factors you aren't looking at that will skew the end numbers...

Let me cite a non-flowbench example. Look at going from a dynojet 248c to a Mustang, and then over to a Dyno Dynamics dyno. All three of them are rear wheel dynos. You take the same car and have all three dynos in the same shop and you will see a huge variance. Does the car loose HP, or is the way the dynos interpret the power input very? The answer is the dynos vary.

Go over to HPE if you doubt this. They have both, in the floor. We've dyno'd on on the dynojet ~470 RWHP, unstrapped a car, and moved over the Mustang and seen ~430RWHP. On a DD dyno the car would be ~390-400RWHP. Do you see where this might not be a fair comparison if you try to compare two different car?


Look, these heads may be the best thing since sliced bread, I'm not saying they aren't. My only point is if you want to compare numbers, put them on the same bench with the same operator. Then, take them to the track... Other than that the rest is just a lot of chest thumping.

BrentB@TEA

Not taken as a bash. If you have to run more timing it means you have to start firing the the plug sooner.
If you have a very efficient chamber you will not need to light the charge as soon as a head with a chamber that is less effcient. The better the mixture motion of the port and chamber, the less timing is required to make as much or more power. Don't forget that the piston is still on the way up the bore when the spark plug lights off. A "fast burn" chamber has a faster moving flame front and hence is more efficient.
Remember how on old school SBC engines everyone used to like to run 38* timing? BBC most guys ran 40* Pontiac guys 34-36. It was mostly due to a combustion chamber design. Todays engines do not need as much timing because the combustion chamber design is way more efficient.

Tony Mamo @ AFR

iTrader: (13)

While we are on the subject of combustion chamber efficiency, I don't think ANYONE could argue that the AFR chamber design is not a superior piece than the "General" offered out of the factory. It's another often overlooked benefit the AFR cylinder head provides. The only way a factory ported casting could be as good is with welding and major surgery....a process that can compromise the ultimate integrity of the cylinder head if not done properly.

As far as trying to compare flow numbers, unless its on the same equipment with the same operator it becomes a completely invalid test. Ive seen a couple of posts that stated the AFR 205 exhaust ports were flowing over 265 CFM @ .600....(we advertise 230 CFM). Although flattering, the reality is you won't see those type of numbers on ANY SF600 or 1020 benchs. What does this all mean....It means if you TRULY wan't to compare flow numbers and actually learn something, it is essential it is done on the same piece of equipment, because much like dyno's, a flowbench is a useful tool but none of them across the country are calibrated the same. Then throw in all the other variables like bore diameter and height, clay and radiused entries, flow tubes, no tubes, and different shaped tubes (straight and curved), and the liklihood of significantly different results moves up exponentially.

Tony M.

flynbludream

iTrader: (1)

I thought the comparison was between this head and a AFR 205? Wouldn't that make the difference 26cc? That looks like a considerable size difference.

JZ'sTA

iTrader: (23)

There is no reason to compair the 205 with a set of stage 3 heads.
Big differences everywhere.
the compairison was between the 225's and the stage 3 6.0 heads from TEA.
The other compairision was between the 205's and a set of stage 1.5 5.3 heads.

JZ'sTA

iTrader: (23)

I could be wrong, but from what I have read TEA has flowed a set of 205's and 225's on their bench.
When they compair numbers it is between both heads on the same bench with the same setup.
If you looking completly at flow numbers then this is a good apples to apples comparision.
It still dosen't show which head will make more power.
I believe you are dealing with 2 of the top head companies on this board.
If someone said pick between a set of 225's and stage 3 heads for the exact same amount of money you would probally see me look like this.

jrp

iTrader: (16)

.....

slyws6

Someone needs to Dyno their AFR 225 heads on a 408 and then change nothing and dyno a set of TEA's equivalent heads and see what happens. That would be more interesting to me, I could care less about flow numbers.

-Sly

Ox-1

I agree.
Would be nice.

JZ'sTA

iTrader: (23)

2 bad none of us have that kind of money.
That would be damn near 5,000 dollars in heads, plus dyno time, plus tune time, plus labor.
Ouch.

xfactor_pitbulls

iTrader: (16)

TEA, sure could do a great comparo on that one. They sell AFR as well as their own heads. So theirs would be the company that makes sense to do it. Or some eccentric owner of a shop. But in all reality, its cool to ask for, but when it comes time to actually do the task I bet most folks would shy away just due to the waste of their time.

FYI, I would be willing to do the test myself. All I need is a donor 408 and the 2 sets of heads. I will handle the rest.

Brandon

BrentB@TEA

I am sure you ment more timing

While we do not have the same type of flowbench. Our bench and AFR's bench are within 1% of each other on the intake side. Our numbers have been different on the exhaust side.

I have seen that before with supeflow stuff. I have never personally seen it with a head flowed on our bench. One time we sent out a set of SBF heads for a magazine artical. The place doing the testing flowed them and ours didn't flow well on thier superflow bench comparred to the our bench and they were down 20cfm from some of the other heads in the artical. However when they were put on ours made 30 more RHHP that the otherheads. So yes I have seen it one way just not the other.
Port volume between our head and an AFR 225 is only 6cc's different. Again using the same beret to CC them.
Wow and your not trying to be ugly??
No one from TEA is chest thumping. Same bench same bore,same set up



Below is some same bench comparisons. First up is an AFR 205 head comparred with our 1.5 head. Notice the intake side flows within 1% of what AFR says it will. Thats why we sell them!
Below is a TEA CNC Ported 6.0l head comparred to an AFR 225 CNC Ported head.These are flowed on a 4.125 bore. The heads are also within 7cc's of eachother in port size. Now before anyone cry's foul about the bore size used the AFR actually fits a 4.125 bore very well. It is the only way we flowed Chris's head since that is his bore size. I also have flow numbers of it on a 4.03 and 3.90 bore. As you can see the AFR head has some killer midlift numbers and is a great product. That why we sell them! Our advantage is we can tailor to the specific customers needs.


_________________TEA 6.0Stg3________________AFR225
.100______________72_______________________68.9
.200______________151.5____________________152.4
.300______________224______________________225.6
.400______________274______________________277.5
.500______________318______________________310.5
.550______________335______________________323.0
.600______________345.5____________________307.6

BrentB@TEA

We are going to do that with a 346 shortly and then follow it up with a 408 in the not so far off future.

BrentB@TEA

I prefer the LS6 chamber but on this we just disagree.


Same bench ,same operator same test conditions post above.

mike c.

iTrader: (1)

my new AFR205's just gained me near 50rwhp(378 to 427hp) on a stang dyno over another sponcers ported head. i went from 115 to 122.2mph in the 1/4mi with them on a slipping clutch that only lasted two runs at the track. i think it may have more in it.

J-Rod

I'm glad to see you posted a side by side test of a TEA 5.3 right beside an AFR 205. That to me gives folks a good side by side comparison to see where your numbers come in at.

My point being is that most of the numbers out there have been derived from SF600 testing. Tony's numbers from AFR were derived from an SF600. So, when someone goes and compares those numbers to some other bench, made by a different mfg, I usually see differences. Even from a 600 to a 1020 you see differences, and those are benches from the same shop.

My point was if you are trying to compare numbers from inside of TEA's operation to numbers from outside its not a fair comparison hence my comment about "chest thumping". I think we've all seen folks take one set of flow numbers from over here at bench Y, and try to compare them to the numbers over bench Z and feel its a fair comparison.

With that said. I appreciate you taking the time to post comparative data derived on the same bench, same buret, same operator, and same orifice. That to me is hard data... The posts above that compared an AFR head, but it made not mention (that I saw) to orifice, 205 or 225, etc...

Let me cite an old post I made about 2 yrs ago

My point again about the chest thumping is benches are but one tool and they need to be understood as such. A delta of before and after performance, just like the track. Hence my comments.

In short, thanks again for the info, now, bolt those bad boy on and share some good news with us....


I'd also like to take a moment to make sure that I am not taking a jab at Visceral, or TEA. I'm not casting doubt on the numbers TEA generated. I fully believe if TEA said they flowed that number on their bench they flowed exactly that. I simply don't want folks to look at one point on a flow sheet any more than they look at one point ona cam (.050). Anyhow, I hope my comments were not mis-construed as casting TEA or these heads in a negative light. I just want folks to understand data in its context.

BrentB@TEA

fair enough