just4bob50
Active Member
Its because of the performance of the AFR heads that TFS now offers CNC porting for their heads as an upgrade. Just look in any summit catalog to find out whats going on.
Is the AFR website full of crap?
- Thread starter ImportEater98
- Start date
just4bob50
Active Member
I just checked the summit catalog and as cast TW heads sell for 1150 if you want the CNC porting the heads jump up to 1850. Now im pretty sure those heads are not worth the $700 mark up.
broncobuddha
Founding Member
vikingpower
New Member
NO doubt, Vic Jr's are $150 less than 185's and make more power!broncobuddha said:
I've said that before, but too many people are stuck on the AFR bandwagon
04sleeper
Founding Member
You get what you pay for.
I have had too many bad experiences with TW heads with the valve guides failing and bolt holes not tapped correctly, etc....
With AFR you get a fully CNC'ed with every port and combustion chamber identical.
I would like to see a shop take the TW and fully CNC them for $200 that you save.
Just going off actual experience with them.
I have had too many bad experiences with TW heads with the valve guides failing and bolt holes not tapped correctly, etc....
With AFR you get a fully CNC'ed with every port and combustion chamber identical.
I would like to see a shop take the TW and fully CNC them for $200 that you save.
Just going off actual experience with them.
These debates come up occasionally, the following is simply information for everyone to use to give anything a fair comparison.....I feel Ed Curtis said it best.
Quote of Ed Curtis "From the past":
"Maybe this will help clear a few things up or possibly confuse more of you. Since I sell both manufactures, (and more) I think I should be able to bring some insight to the buyer. For the record, Trick Flow sponsors my Real Street car, AFR and I have a very tight relationship and Edelbrock sponsors my twin in Hot Street so I nothing to gain or lose in this explanation.
First of all, you must compare the two (or three) heads correctly.
The Edelbrock Performer/RPM and the AFR 165/185 are not of the same configuration as the Twisted Wedges. AFR and Edelbrock are true OEM type inline valve, 20* valve angle heads. Their valve centerlines in relation to the bore axis are also Ford locations so they are considered as direct a bolt on as possible. One should be comparing these two heads to the GT40 type heads and not a TW but that's a whole other story....
The TW heads on the other hand are designed with a 15*/17* valve angle and also have the valves rotated about the bore centerline so they can not be considered a true inline valve Ford head. These rolled valve angles contribute quite a bit to better flow figures out of the ports than "most" standard location valve heads, but not all heads. Also, by rotating the valves around the bore centerline, these heads allow the intake valve to enter into the center of the bore allowing for good flow figures and create a short intake runner. All these features contribute to a good flowing head.
Now if you wanted to compare some important features between the heads, just look into port volume and cross sectional area of the intake ports. Though AFR claims 165 cc and Edelbrock claims 170 cc intake ports, they are true inline heads so their overall design is similar and their comparison flow figures to each other are valid. TW on the other hand, claims a 170 cc intake port but its runner length is approximately 3/8" shorter than the real inline heads and hence, has a considerable larger cross sectional area to obtain that volume.
If you were to create any comparison of the 170 cc intake port of the TW heads to another head, you should do it with a 185-190 cc intake port not a 165 cc or 170 cc port from a true inline valve head.
There are a lot of shops now explaining about curtain area and other factors they use to determine if a port is really an efficient one or not. These guys are no longer going by just flow figures so why should you?
When you compare heads and flow figures, a lot of other important items must be incorporated. Doing anything else would be like comparing a Blue Thunder head to a Cleveland Boss head (or for that matter a big block Chevy) just because they are both canted valve heads.
Back on topic..
Now let's talk about valve size. The AFR and Edelbrock heads are currently using 1.90/1.60 valve configurations and the TW heads use a 2.02/1.60 configuration.
To attain ~250 cfm at .500" lift through an intake port, the TW heads use a 2.02 valve and the AFR heads (and Edelbrock) utilize a 1.90 intake valve, though Edelbrock claims more like 230 cfm. If you add in the fact of the larger cross section, the rolled valve angle and that bigger intake valve of the TW head, don't the AFR 165 heads look like a better head for a naturally aspirated, small cube, 300-350 RWHP application? If you don't understand this, just stop reading. "
Let me know if you have any further questions, Jason
Ed, if your reading, I hope you don't mind
, see ya at PRI
Quote of Ed Curtis "From the past":
"Maybe this will help clear a few things up or possibly confuse more of you. Since I sell both manufactures, (and more) I think I should be able to bring some insight to the buyer. For the record, Trick Flow sponsors my Real Street car, AFR and I have a very tight relationship and Edelbrock sponsors my twin in Hot Street so I nothing to gain or lose in this explanation.
First of all, you must compare the two (or three) heads correctly.
The Edelbrock Performer/RPM and the AFR 165/185 are not of the same configuration as the Twisted Wedges. AFR and Edelbrock are true OEM type inline valve, 20* valve angle heads. Their valve centerlines in relation to the bore axis are also Ford locations so they are considered as direct a bolt on as possible. One should be comparing these two heads to the GT40 type heads and not a TW but that's a whole other story....
The TW heads on the other hand are designed with a 15*/17* valve angle and also have the valves rotated about the bore centerline so they can not be considered a true inline valve Ford head. These rolled valve angles contribute quite a bit to better flow figures out of the ports than "most" standard location valve heads, but not all heads. Also, by rotating the valves around the bore centerline, these heads allow the intake valve to enter into the center of the bore allowing for good flow figures and create a short intake runner. All these features contribute to a good flowing head.
Now if you wanted to compare some important features between the heads, just look into port volume and cross sectional area of the intake ports. Though AFR claims 165 cc and Edelbrock claims 170 cc intake ports, they are true inline heads so their overall design is similar and their comparison flow figures to each other are valid. TW on the other hand, claims a 170 cc intake port but its runner length is approximately 3/8" shorter than the real inline heads and hence, has a considerable larger cross sectional area to obtain that volume.
If you were to create any comparison of the 170 cc intake port of the TW heads to another head, you should do it with a 185-190 cc intake port not a 165 cc or 170 cc port from a true inline valve head.
There are a lot of shops now explaining about curtain area and other factors they use to determine if a port is really an efficient one or not. These guys are no longer going by just flow figures so why should you?
When you compare heads and flow figures, a lot of other important items must be incorporated. Doing anything else would be like comparing a Blue Thunder head to a Cleveland Boss head (or for that matter a big block Chevy) just because they are both canted valve heads.
Back on topic..
Now let's talk about valve size. The AFR and Edelbrock heads are currently using 1.90/1.60 valve configurations and the TW heads use a 2.02/1.60 configuration.
To attain ~250 cfm at .500" lift through an intake port, the TW heads use a 2.02 valve and the AFR heads (and Edelbrock) utilize a 1.90 intake valve, though Edelbrock claims more like 230 cfm. If you add in the fact of the larger cross section, the rolled valve angle and that bigger intake valve of the TW head, don't the AFR 165 heads look like a better head for a naturally aspirated, small cube, 300-350 RWHP application? If you don't understand this, just stop reading. "
Let me know if you have any further questions, Jason
Ed, if your reading, I hope you don't mind
, see ya at PRI
04sleeper
Founding Member
Hissing Cobra
Founding Member
I've got the AFR 185's on my naturally aspirated 306. My combo is almost identicle to the one that John (ImportEater98) posted from the AFR website. I've got a little bit more compression (10:8:1 vs. 10:1:1) but a little less cam (Elgin Pro Stock 536/560, 248/258 @ .50 with 1.6 rockers vs. Comp Cams 282, 565/574, 232/240 @ .50 with 1.6 rockers.) I did not use a victor manifold, nor the 650 speed demon. Instead, I chose a dual quad intake manifold and two Edelbrock 500's.
My combo made nowhere near the advertised horsepower (455 @ 6,100 rpms.) I made 307 at the wheels (@ 6,400 rpms) which equates to approximately 360-370 at the flywheel. I know that my dual quads probably cost me some horsepower, but I don't think it would cost me that much (80 or so.) Anyone agree? Are their numbers rated on an engine dyno only, with no accessories whatsoever? Jason?
I'm not trying to start a bitch fest here, I'm just trying to understand how these numbers are advertised and if they're actually accurate. I also believe that it's damn near impossible to see 455 horsepower out of a naturally aspirated 302. If you did, it wouldn't be streetable.
By the way, I'm a HAPPY AFR customer. These heads were perfect, right out of the box.
My combo made nowhere near the advertised horsepower (455 @ 6,100 rpms.) I made 307 at the wheels (@ 6,400 rpms) which equates to approximately 360-370 at the flywheel. I know that my dual quads probably cost me some horsepower, but I don't think it would cost me that much (80 or so.) Anyone agree? Are their numbers rated on an engine dyno only, with no accessories whatsoever? Jason?
I'm not trying to start a bitch fest here, I'm just trying to understand how these numbers are advertised and if they're actually accurate. I also believe that it's damn near impossible to see 455 horsepower out of a naturally aspirated 302. If you did, it wouldn't be streetable.
By the way, I'm a HAPPY AFR customer. These heads were perfect, right out of the box.
Hissing Cobra
Founding Member
87'GTstang said:
Overkill? How so? If AFR says that you can use the 185's on a 302 and get 455 horsepower out of it, how can that be overkill? I know that the majority of people use the 165's on the 302's but the fuel injected cars with the hydraulic cams don't seem to be able to rev to the 6,500+ rpm limit. We did a lot of research before choosing the 185's because my solid lifter cam was advertised to make power all the way to 6,500 rpm's. We chose the 185's so that the engine could breathe a little better on the top end.
My setup may be better on a 347, 351, or even a 351 stroker based engine, but that's not the issue at hand. The issue at hand is whether or not the advertised AFR combo will make 455 horsepower. I suppose that it's possible but I'm having a hard time believing it without the aid of a power adder. Has anyone actually built and dynoed AFR's combo?
Rick91GT, I think that I read on this site that you've built 400+ horsepower small blocks. Were they 302's? Strokers?
Just curious that's all.
BlooDReigN
Member
I see nothing excessive about any of the parts Hissin Cobra has on his 306, and I would certainly never even consider any of those parts on my 351 based stroker.
307 at the wheels from a naturally aspirated 306 is nothing to scoff at. Another thing you guys forgot about that could also inflate the numbers is light weight engine internals like hypereutectic pistons. They didn't have to build the motor to last very long, just long enough to give them a number that would look good on a chart
All that combined with no drivetrain or accessories dragging the engine down, and I could see 450 crank hp coming from the combo they are running.
307 at the wheels from a naturally aspirated 306 is nothing to scoff at. Another thing you guys forgot about that could also inflate the numbers is light weight engine internals like hypereutectic pistons. They didn't have to build the motor to last very long, just long enough to give them a number that would look good on a chart
All that combined with no drivetrain or accessories dragging the engine down, and I could see 450 crank hp coming from the combo they are running.
"I chose a dual quad intake manifold and two Edelbrock 500's."
Maybe i'm just not thinking right, but a dual quad and two 500 cfm carbs is a hell of a lot of intake for a 5.0. The AFR 185s are fine if the airflow is right. Just a personal opinion but it just doesn't seem like things are as well matched as they could be and that a lot of air is trying to be rammed into the engine that cannot
What I am getting at with the AFR combo is that maybe it was that more of a complimentary package that was ran.
How is the low-end power and driveabilty down low?
455 is a lot but if you have an engine builder set it up perfectly as a combination, I would think it could get there. Driveabilty would suffer for the street definitely but who builds and engine NA with double the stock power and expects it to run well at 1500 rpms cruising?
Maybe i'm just not thinking right, but a dual quad and two 500 cfm carbs is a hell of a lot of intake for a 5.0. The AFR 185s are fine if the airflow is right. Just a personal opinion but it just doesn't seem like things are as well matched as they could be and that a lot of air is trying to be rammed into the engine that cannot
What I am getting at with the AFR combo is that maybe it was that more of a complimentary package that was ran.
How is the low-end power and driveabilty down low?
455 is a lot but if you have an engine builder set it up perfectly as a combination, I would think it could get there. Driveabilty would suffer for the street definitely but who builds and engine NA with double the stock power and expects it to run well at 1500 rpms cruising?
Hissing Cobra
Founding Member
My combo doesn't have a lot of low end torque so I've compensated with 4.30 gears. Driveability on the street is excellent. It idles around 1,000 rpm's and doesn't stumble, flood, surge, load up or hesitate. I run 1.64-1.81 60' short times at the track on my way to 12.40-12.80 timeslips. Here's a pic of my dyno graph. You'll notice that despite 1,000 cfm of carburetion, it doesn't run rich at all (also, the Victor Jr. outflows my dual quad intake.) The graph is at 13.5 on the air ratio between 3,400-4,300 rpms and declines as I build more power down to the 12.5 range, which is where I want it to be. It's tuned pretty good for two carburetors.
Personal taste and liking is what it is all about. Just seems that Since you do have a setup like that, that something is lacking and that more than just 307 rwhp could be squeezed out of it all
Glad to see that it seems to run that well for you though, all that really matters is the owner's happiness
Glad to see that it seems to run that well for you though, all that really matters is the owner's happiness
Dark Knight
Founding Member
Hissing cobra, your prob is that intake.. the ports on those are way to small.. I have an old weiand dual quad intake and the ports arent much bigger than a performer.. if you havent already tried it and have room... run a couple open spacers, it will helps some.. but I wouldnt be suprised if a stealth or RPM gave you another 50HP..
might have that intake extrude honed too..
might have that intake extrude honed too..
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