AFR MOPAR 340 HEAD TEST!

[PRH]

I’d expect an even bigger difference in power if the test had been done using a short block that could fully use up the air flow of both heads.

But as for the AFR’s themselves……”so far, so good”.

 

[273]

I'm not going to argue with you. Glad you can do your own work, so can I. I encourage everyone to do as much as they can for themselves. But I stand by my statement that most people in the hobby, cannot for whatever reason (skill, space, time, tools) port an iron OEM head with positive results that approach the performance level of one of these aluminum heads. Thus, having ready to go options off the shelf that provide a significant increase over stock iron heads, is a good thing. Doing a gasket match on the ports and knocking some burrs off isn't going to take an OEM iron head into the realm of an aftermarket Eddy/ProMaxx/AFR type aluminum head. Getting that kind of result from an iron head takes skills and tools that 90% of enthusiasts just don't have and these days finding a shop that can/will do a set of iron heads to that level will likely cost you the same as a set of Trick Flow 190's.

Totally agree 99% aren't gonna port their own heads for one reason or another, shouldn't be suggested as often as it is like it's a realistic option for most, if your able to bonus. Plus most can't do their own machining, milling, valve jobs, guides etc.. so unless your heads only need a lap job your gonna be investing a good chunk of money to rebuild them that could go towards a good set of aftermarket heads.

 

[Oldiron440]

Here's my 0.02 on a few of the issues being discussed here. Can the iron 360 heads make as much power as the AFR? Maybe, but it would take a huge amount of work. The restriction to flow in the 360 style head is mostly around the apex area. That huge, ugly valve guide vein takes up too much real estate. To get a 360 head flowing much over 200-210 cfm requires a lot of deep port work. Opening up the pushrod pinch will do some good (very little really) in the mid lift range. A 2.02 valve with a nice valve job and bowl blend will help low and mid lift flow a bunch. Without addressing the flow restriction at the apex, opening the pushrod pinch and opening the valve and bowl area will actually HURT high lift flow due to increased flow separation over the short turn. Then there's the issue of the 72cc 360 chamber vs the 63-65cc AFR chamber. Totally different compression and quench characteristics.

As far as the TF vs the Chinese heads. The TF probably is a little nicer than the AFR, but only a little. TF uses multiple foundries in the states and has some difficulty maintaining consistent supplies. I have a set of TF heads that are a few years old and those heads look quite different from a TF head I purchased a few months ago for porting work. It is obvious that they came from 2 different foundries. The AFR head comes from the Steven Sun foundry, which does a really nice job with their castings. The brass guides and seat rings are pretty good stuff and machinability is on par with the TF. TF valves and springs are nicer than any Chinese products I have seen. I have no idea what valves and springs AFR is using.

One other note. I have flow tested 8mm valves vs 11/32 valves. There is no difference that I could detect. Going from a stock 3/8 stem factory valve to a reduced stem 11/32 valve is worth about 4-5 cfm on the top end. There is a significant weight difference in an 8mm valve vs the 11/32 however.

I wasn’t talking about getting all the power off the AFR heads from stock heads but if you can get fifty percent of the difference between the AFR and stock heads for $500 I’m not sure the other fifty percent is worth $1500. If you’re starting with a pair of garbage heads new makes sense. One more thing is running a new pair of heads out of the box can be risky, everything from face finish to seats, guides and valve runout can need addressing before use so there can be hidden costs…

 

[273]

I’d expect an even bigger difference in power if the test had been done using a short block that could fully use up the air flow of both heads.

But as for the AFR’s themselves……”so far, so good”.

10-20 more degrees and 0.050"-0.100" more lift would really wake that 340 up, I feel a lot are glossing over how small of a cam their running.

 

[273]

I wasn’t talking about getting all the power off the AFR heads from stock heads but if you can get fifty percent of the difference between the AFR and stock heads for $500 I’m not sure the other fifty percent is worth $1500. If you’re starting with a pair of garbage heads new makes sense. One more thing is running a new pair of heads out of the box can be risky, everything from face finish to seats, guides and valve runout can need addressing before use so there can be hidden costs…

If it's in your wheel house and can gain 30+ hp for $500 sure makes sense, but most can't or at least unwilling to try or just don't want to and glad to buy 400-500+ hp heads for 2k+.

 

[TT5.9mag]

One other note. I have flow tested 8mm valves vs 11/32 valves. There is no difference that I could detect. Going from a stock 3/8 stem factory valve to a reduced stem 11/32 valve is worth about 4-5 cfm on the top end. There is a significant weight difference in an 8mm valve vs the 11/32 however

Great post. One question for you. At what flow level were you testing the valve stem diameter difference? Do you think on a more serious head you’d see bigger gains? Or on a less serious head there would be bigger gains?

 

[Oldiron440]

If it's in your wheel house and can gain 30+ hp for $500 sure makes sense, but most can't or at least unwilling to try or just don't want to and glad to buy 400-500+ hp heads for 2k+.

In case you missed it the stock heads made damn near 400 hp, I’m not impressed with the AFRs on this 340. Maybe if it was 400” with a cam in the 250@050 duration range the difference would be more…
I would have liked to see how the heads they didn’t run would have compared, the heads he put together for the engine and took off to run the stock heads.

 

[TT5.9mag]

In case you missed it the stock heads made damn near 400 hp, I’m not impressed with the AFRs on this 340. Maybe if it was 400” with a cam in the 250@050 duration range the difference would be more…
I would have liked to see how the heads they didn’t run would have compared, the heads he put together for the engine and took off to run the stock heads.

Me too but 365 isn’t “damn near” 400 in my book.

 

[NC Engine Builder]

I think that's pretty darn good "streetable" power out of that combo. Nothing exotic, and over 400 hp... quite simular to the 340 that I did for @gzig5

 

[TT5.9mag]

I think it’s great simple power out of a short block that’s similar to what most of the mopar crowd is running. Either a 318-340-360. It’s a good representative test. If he tested the afr against a pro ported X head who does that information benefit other than the head porter?

 

[TT5.9mag]

Richard on his live feed yesterday went a little deeper into the behind the scenes at Dulcich’s place.

 

[273]

In case you missed it the stock heads made damn near 400 hp, I’m not impressed with the AFRs on this 340. Maybe if it was 400” with a cam in the 250@050 duration range the difference would be more…
I would have liked to see how the heads they didn’t run would have compared, the heads he put together for the engine and took off to run the stock heads.

Could you port out stock heads to make these and even higher hp numbers of course you can, but the point is most are not and glad they can just order a set of 450 hp +heads, if that's not for you and some others here that's fine and port away.

I'm not making a case to buy AFR heads, to me all this test shows is decent power can be made with reasonable parts if you rather do it with ported stockers go for if some rather TF's or SM or W2 or whatever heads then do.

 

[Earlie A]

At what flow level were you testing the valve stem diameter difference? Do you think on a more serious head you’d see bigger gains? Or on a less serious head there would be bigger gains?

Here's a couple of tests from the past. Test 1348/1349 is a Trick Flow port, 45 deg seats, 2.08 valve flowed with no manifold. Valve was changed from a 11/32 Ferrea to a 8mm Trick Flow.

Second test is a Promaxx port , 50 deg seats, 2.08 valve flowed with a Super Vic manifold attached. Valve was changed from a 11/32 Ferrea to a 5/16 Manley 10 deg.

In both cases the 11/32 valve averaged slightly higher flow, but in both cases the average changes are less than 1 CFM. There are a lot of things going on here as well. Change in valve manufacturers, change in valve margin width. Change in valve seat and back cut widths. In one case going from a 12 deg to a 10 deg nail head. Not sure if I even changed the guide in these tests. Sometimes I just wrap the valve with thin shim stock. So there could be concentricity issues, etc. etc.

My big takeaway was this - no real difference going from 11/32 to 8mm (or 5/16). The shape of the valve head doesn't change much (if staying with 12 degree) and neither does the diameter of the base of the valve stem since the 11/32 valve is a reduced stem valve. Only the upper valve stem (the part that goes in the guide) changes diameter.

 

[273]

I think it’s great simple power out of a short block that’s similar to what most of the mopar crowd is running. Either a 318-340-360. It’s a good representative test. If he tested the afr against a pro ported X head who does that information benefit other than the head porter?

100%

If the X heads or whatever heads are ported to similar specs as the AFR's I'd imagine the dyno results would be similar.

 

[PRH]

I think an in between test with something like a basic bowl blended factory head with 2.02 valves(220-230+/-cfm) would have been an interesting addition to the mix.
Something representative of what a shop that “dabbles” in porting might turn out.

 

[MOPAROFFICIAL]

I think a test between the AFR and your average pro ,if you want to call anyone that "Porter" would not necessarily make the porter look good/benefit other than validating his work or verifying what works..as much as would show the limitations to the designs, both aftermarket and stock. They can only do so much around that 50 something year old engine design. The technical side is more interesting to me. Most seasoned individuals can get the same results when it comes to "porting".
The test on the other hand, for the enthusiast...well maybe It lends support/evidence to whether one should bother porting his heads to meet the power requirement..or not going that route and simply buying an Afr , TriCkFloW etc.
I enjoy seeing elbow grease keep up the good fight.. as well as the old "leave well enough alone" or "don't fix what's not broke".

Remember when they tested the LD 340 against the new RPM intake? What was it like maybe a 9 or 10 horsepower difference at ? Rpms?.. and thats as cast comparison.
I still run a LD 340, I put a spacer to make up the difference in plenum height as well. I like the cool old stuff and there's a reason why it makes so much power, because sometimes they get it right the first time

 

[273]

Well it's Steve's dyno I imagine he'll be putting out his own dyno video's so we may get some other heads being tested.

 

[a-bodyguy]

would you spend 2K for 60hp and 39tq?

tti headers are a grand for 20 hp
iam for sure not spending 1000 1500 to redo my tired 68 x heads if you can buy those 2k and remove weight as well
that motor with a progressive 200 shot with factory 340 logs cal tracs 3.91s and a drag radial would suck the paint most everything

 

[TT5.9mag]

Here's a couple of tests from the past. Test 1348/1349 is a Trick Flow port, 45 deg seats, 2.08 valve flowed with no manifold. Valve was changed from a 11/32 Ferrea to a 8mm Trick Flow.

Second test is a Promaxx port , 50 deg seats, 2.08 valve flowed with a Super Vic manifold attached. Valve was changed from a 11/32 Ferrea to a 5/16 Manley 10 deg.

In both cases the 11/32 valve averaged slightly higher flow, but in both cases the average changes are less than 1 CFM. There are a lot of things going on here as well. Change in valve manufacturers, change in valve margin width. Change in valve seat and back cut widths. In one case going from a 12 deg to a 10 deg nail head. Not sure if I even changed the guide in these tests. Sometimes I just wrap the valve with thin shim stock. So there could be concentricity issues, etc. etc.

My big takeaway was this - no real difference going from 11/32 to 8mm (or 5/16). The shape of the valve head doesn't change much (if staying with 12 degree) and neither does the diameter of the base of the valve stem since the 11/32 valve is a reduced stem valve. Only the upper valve stem (the part that goes in the guide) changes diameter.

View attachment 1716443546

View attachment 1716443547

Thanks for the info. Very well done.

 

[NC Engine Builder]

Here's my 0.02 on a few of the issues being discussed here. Can the iron 360 heads make as much power as the AFR? Maybe, but it would take a huge amount of work. The restriction to flow in the 360 style head is mostly around the apex area. That huge, ugly valve guide vein takes up too much real estate. To get a 360 head flowing much over 200-210 cfm requires a lot of deep port work. Opening up the pushrod pinch will do some good (very little really) in the mid lift range. A 2.02 valve with a nice valve job and bowl blend will help low and mid lift flow a bunch. Without addressing the flow restriction at the apex, opening the pushrod pinch and opening the valve and bowl area will actually HURT high lift flow due to increased flow separation over the short turn. Then there's the issue of the 72cc 360 chamber vs the 63-65cc AFR chamber. Totally different compression and quench characteristics.

As far as the TF vs the Chinese heads. The TF probably is a little nicer than the AFR, but only a little. TF uses multiple foundries in the states and has some difficulty maintaining consistent supplies. I have a set of TF heads that are a few years old and those heads look quite different from a TF head I purchased a few months ago for porting work. It is obvious that they came from 2 different foundries. The AFR head comes from the Steven Sun foundry, which does a really nice job with their castings. The brass guides and seat rings are pretty good stuff and machinability is on par with the TF. TF valves and springs are nicer than any Chinese products I have seen. I have no idea what valves and springs AFR is using.

One other note. I have flow tested 8mm valves vs 11/32 valves. There is no difference that I could detect. Going from a stock 3/8 stem factory valve to a reduced stem 11/32 valve is worth about 4-5 cfm on the top end. There is a significant weight difference in an 8mm valve vs the 11/32 however.

In my mind, the REAL benefit of using the 8mm stuff is weight, and since they are essentially LS valves, lots of affordable options for valves and springs.

 

[cookietruck]

10-20 more degrees and 0.050"-0.100" more lift would really wake that 340 up, I feel a lot are glossing over how small of a cam their running.

Little cam and the motor made 65hp more…for $1500
Seems pretty nice to me.
Especially if someone were looking at redoing steel heads.

 

[gzig5]

I think that's pretty darn good "streetable" power out of that combo. Nothing exotic, and over 400 hp... quite simular to the 340 that I did for @gzig5

Yup. 440lb-ft @4350rpm and 460hp @6300rpm with essentially no tuning. Promaxx 171 heads lightly tickled and a used SFT cam 272/276, 242/247 @ .050", .540/.549" w/ 1.5 ratio, 109 LS. I think my cam is just a notch bigger than the 268 in the AFR test. It wasn't done yet at 6300 and we didn't have the intended 1.6 ratio rockers mounted so there is some more in the back pocket. It's KILLING ME that the car isn't ready for the engine yet.

 

[MOPAROFFICIAL]

Well it's Steve's dyno I imagine he'll be putting out his own dyno video's so we may get some other heads being tested.

I have some ported iron heads that I would definitely lend for a test like that.

 

[fishmens67]

Little cam and the motor made 65hp more…for $1500

It doesn't take much to tickle some.
I'd be depressed after spending $1500 for 65hp.

 

[NC Engine Builder]

It's a little disingenuous to say "65 hp for $1500" because you would have had to spend money on the iron heads to make them fresh enough to use, THEN add up your time porting them. So the actual cost difference in the real world is almost zero.