What's wrong with AFR's exhaust port?
 

On another thread it was brought up that AFR's exhaust port leaves a lot to be desired. I would like to know what's wrong with the port... Please don't reply to this thread with flow numbers on such and such's flow bench. When it comes to the exhaust side of things you minus well throw the flow bench in the garbage because it means nothing. You can pretty much do that for the intake side of things as well but we will leave that for another thread because this is going to be complicated enough. So what's wrong with the port I ask? Countless engine builds putting up big numbers N/A and Boosted. I really want to know what's wrong with it.

Its a lousy piece of crap because somebody in the internet said it was.

here we go.:food-smiley-007::food-smiley-007::food-smiley-007:

IVe seen the AFR heads make some great power. I also think their pricing is pretty good as well.

I do think that cylinders heads bring up the ford vs chevy vs dodge kind of debate. Today's market has alot to offer as far as cylinder head choices. Theyve all come a long way , AFR, Brodix, Dart, etc. Lots of sizes shapes, and so on available. Plus we have many many head porters that can do alot too to improve on most of these heads.

I feel the statement of there being something "wrong" with afrs exhaust port is poorly worded based on someones opinion, and simply an incorrect statement .

maybe it was just someones application they used said AFRs on... wrong match? AFRs are "top shelf" along with Dart and Brodix IMO...

all im going to say is i always used dart heads for years but after working with bob i decided to try some afr,s.i am very happy with the afr,s but i still love the dart,s.imo they are pretty even but through bob the afr is a better value.again,just my opinion so don,t bother flaming me.

After much research , I just laid my hard earned money down on a set of AFR 315's . The voices of experience here lead me to believe I'll be happy I did . Can you say engine jewelry that performs as good as it looks......:drool1: :cool-smiley-011:

AFRs are great.

:food-smiley-007::food-smiley-007::food-smiley-007::food-smiley-007: I brought extra.

:waffen093: lmao!!!

:popcorn: thanks for sharing !

Says who ???

I've used both Darts(355 cnc) and AFR's(357's),made ~1200hp(touch more) w/ both and the cams were very similar.The 4L whipples were getting close to my safe(I don't like to run over 9psi) limit.

JimV, read the entire thread last night. http://www.offshoreonly.com/forums/g...s-540-sci.html

I think black baja was referring to what "Ben Perfected" stated in the other thread. What I got from the thread a couple years ago where JimV was posting, was that when he flowed several sets of AFR heads they did not flow the numbers claimed on AFRs website , on his flow bench. I think?

maybe Bob will chime in, He'll set ya straight

Gotcha Joe, I thought he might have read the thread from 2011.

Sounds like he already set you straight, me too. Hows the new boat? All you expected?

I believe he said it can be improved. Just like the Dart intake port, his opinion. I don't believe something is wrong with the port.

They sound good to me.

Im sure it will be when I get it, travel to Buff. NY this time of year is a bit tricky

Ok, thought you already had it.

Want a much better exhaust port design?

You can, but you'll have to change pistons, rocker arms, pushrods, valve covers, intake, headers, and etc, etc, etc.

http://www.brodix.com/wp-content/gal...03_exhaust.jpg

https://www.youtube.com/watch?v=LmVVoUT7Di0&feature=player_detailpage
:cool-smiley-011::circle::circle:

^^^^ I bet my man has a magic room. :nicethread:

and don,t forget the guide work every 50 hrs.

Some good arguments, but I guess my .02 is I suppose if someone can show me un biased proof of a back to back conclusive engine test on the dyno with all else being equal using the same engine, other than a head swap comparison, then until then, I will stick with the port that comes from AFR factory. I like making more power thru the cylinder heads, but I figure that ol' warsh tub of mine is gonna go plenty fast enough for what I want.

If somebody does a back to back test one day using AFR's factory cnc'd exhaust port vs a modified AFR cnc'd exhaust port that is supposed to be better, then when it comes time that I must do a rebuild on my engines, then then perhaps I will consider having my AFR cnc'd exhaust ports modified.

If Smitty ("Articfriends") 540cid engine can make 1115hp on the dyno with his little 315cc AFR's, then that is good enough for me for now---he's an honest and respected test bed.

A buddy of mine built a pair of M4 Procharged 522ci engines. Each engine was dynoed at least twice, maybe even 3 times, with different cams, carbs, etc. Anyhow, I was there and witnessed the engines make big power on the dyno runs. They exceeded 1200HP each time, just at a little different rpm range due to the cam changes. However, they did so with alot of boost. 15lbs if I recall right. we told him that was too much boost for his combo, and it was, but he liked that 1200hp number.

They did that, with Edelbrock Performer RPM aluminum heads. So, technically, I can say Ive seen the edelbrock heads support 1200hp on the dyno. However, I would be willing to bet anything that bolting a set of AFR heads, Dart CNC heads, that they would have gained quite a bit of power hands down. And made as much power as the edelbrocks, but with less boost, and simply been a better setup all around.

I think their is a big misconception out there that forced induction engines don't respond as well to higher flowing heads, as much as a N/A does. Also, when power packages are looked at in that manner, one must consider not all forced induction systems are created equal. Lets say you have a roots blown setup making 1000HP with XXX heads, and you thought the heads were hitting a wall airflow, or power wise. You may then generalize, and say xxx heads are good up to 1000HP. But, you have to figure in the other things too. Like parasitic loss. The dyno is simply measuring power at the flywheel. It does not know what the parasitic losses are. So that 1000HP roots blown XXX head setup that was maxed out, may actually support 1100+HP with a whipple, or procharger, psi, turbo, etc. Then of course there is air temperature differences from blower to blower, and many other variables that can change the output at the flywheel.

Fwiw, that engine combo above I mentioned, got tossed out in favor of, bolting on a pair of AFR 315 heads, a 1071 littlefield, blower shop intercooler, and cams from Bob M. It made 985HP, with 10lbs of boost on the dyno, and 930HP with 8lbs of boost. The combo is very nice, and we are excited to install them in his 42 Fountain soon and see how it runs.

I guess my point is, if smitty turned his boost up even more, I think you'd see those heads support even more power with the 315 AFRs. Sorry for getting a little off topic, as this post really has no answer to the op's question. :popcorn:

Smitty is a good example, because he had other heads before (Merlin's) and couldn't make anywhere near the power he was looking for, even turning up the boost. He got the AFR's and surpassed the power he was looking for even with boost he was more comfortable with.

BObL ran into this also. Too much boost for the power (some box stock basic Brodix) and more boost wasn't doing anything. I think BobL ended up going to a set of Ported Brodix's or etc and made his number with acceptable boost #'s.

Many more example's, but these where chosen because of being members here, to agree with MildT and many others. Adding more boost is not always the answer - ie: doesn't always make more power if the combo of parts is not there to support the added airflow.

that engine with 17 lbs boost made close to 1300 hp but it was not safe on pump gas.the new roots combination made just shy of 1000 hp but imo,it will be a much better engine and should last for a long time with only oil changes and a lot of fuel.

Also can be a factor when you run out of blower, or camshaft as well. You get to the point of diminishing returns. Sometimes you simply have to make more power on "motor'', if you are compressor limited. Like trying to make 1000HP with a 177 blower on a 454. Not gonna happen. But it can happen with a big blower and alot of boost. today, builders are doing 2000HP with conventional heads and turbos and centrifugals.

Definately not with schitty or just okay conventional heads.

I think Steve Morris does alot with the Brodix Head hunter heads, but heres a setup with the 355cc Dart conventionals. https://www.youtube.com/watch?v=tTZkIG3RExI#t=208

Ah, Steve Morris. He was the machinist at the local Napa store in my home town. He did all the machine work on my first engine rebuild. 2.8L V6 GMC Jimmy engine. He sent me home with a machined block, a master rebuild kit, torque spec, clearance #'s and plasti-gauge. Told me what to do and how to read the plasti gauge. I asked what oil to run and he said straight 30w, nothing any thinner. 180,000 miles later I sold it $1500. Lol

Nice! I always like watching his builds. Some cool stuff. Anyone have any extra butter? :popcorn:

He also freshened up the heads. I believe he went to Dart a few months after that.

Where is Steve Morris located now?....still in the Muskegon area?

Yes Muskegon area.

I remember a few years back we were talking about achieving HP goals. I was asking him questions about superchargers, blowers and turbos. He said, "Superchargers to about 2000HP and Turbos after that. Turbos are for when you get serious about making power." Lol

http://www.stevemorrisengines.comSteve Morris Engines

Racing Car Parts Store
750 E Ellis Rd, Norton Shores, MI 49441

4 pages and still nothing wrong with the port? Here is a company that has 15 5axis CNC machines and someone makes a comment that the port leaves a lot left to be desired. I'm sorry guys I just don't buy it. With all the engineers and air flow specialists that work for the company don't you think that if a problem was discovered with the port a few changes would be made to the program and corrected immediately. I think what we have here is a few people that don't know what they are doing/ talking about making statements about a great product that they have no buisness commenting about. Any monkey with a dremel tool and a flow bench can get a port to flow more CFM but this doesn't equate to making horsepower.

I think I will stay out of these threads and just "like" the winners.