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Discussion Starter · #1 ·
Which would you choose and why. Trying to weigh the pros and cons of each.
People with educated opinions on this topic only please...I don't care if your brothers wifes uncles friend had these heads and it smoked!
 

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Discussion Starter · #3 · (Edited)
Duh, that would help now wouldn't it. I will be mounting these on a CHP 347 street fighter, I have a Edelbrock Performer RPM II intake, 75mm Holley TB, 30# injectors,80mm Pro-m Mass air, Crane roller 1.6 rockers, cam with somewhere in 575 area for lift and 1 5/8 long tube headers which flow into Flowmaster 2 chambers. Hope that helps
 

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heads

if you plan on porting, etc. Go with the Jr's. If you go box stock go with the AFR's. The 185's will outflow the Jr's Box to box stock, but you can get a tad bit more out of the Jr's with some work.
 

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whatever head you get use 13/4 longtubes not those 15/8s

i like the jrs. myself their a nice head right out of the box and you can grow with them.

i doubt the 185s outflow the jrs.

IMO i would use a bigger intake as well but thats just me.

i have nothing against the 185s their a very nice head as well but if i was use AFRs it would be the 205s.
 

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Discussion Starter · #6 ·
So there are differences but they are minor, I like the Edelbrock products and I have always used them and it looks like it will stay that way. Thanks for the input people
 

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I don't think the 185's outflow the Jrs stock for stock. Jrs have another 25cc on the intake port and flow something like 285 and 225 out of the box.

For a street strip car the Viccy's are the choice, for a street only car 185's would offer more torque (which you don't really have to worry about with the added cubes).
 

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Need more info. If you want important advice like part selection, please try to give us more info. For me to give anybody advice I need to know; compression, cam type and specs, heads, any port work, weight, gear, tires, trans, convertor if automatic, purpose of car, and if any power adders.

Later, Greg(XSR)
 

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custom ground cam 234-240ish duration with 570-590 lift. these arent the exact specs but there somewhere within these numbers. 3.73 gears,1 3/4 lt,80mm mam,75mm tb, beween 10.66-11.0 flat top pistons, either vickys or afr 185s. intake?
 

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heads & intake

I would go with the victor Jrs.Flow isnt the only thing you need to look at.Port volume needs to be considered too.The bigger the motor or should I say stroke,the more runner volume you need.The less stroke the less volume.You put a victor Jr on a stock short block with 9-1 comp. and it wont fall out of a tree!now you take a 347 with 5.315 rods and put victor jrs(210cc)on it and it will ride!I would put a TFS-R on it but only if you have means to raise the factory rev limiter.It needs to turn 6700 min.Otherwise put a SYSTEM MAX on it.victor jr.s can be tricky to cam,more so when they are ported because the exhaust port is so strong so make sure whoever you get a cam from has experience with these heads.Also the cams .050 #s arent everything either,you could take 10 cams with the same .050 #s and they would all act different.Pay the extra money and by a cam from someone you know has experience with this combo.GOOD LUCK!
 

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call up Ed Curtis at FTI or Flowtech Induction Systems...his custom grinds are some of the best in the country and his prices for what you get are unbeatable, i suggest you at least give him a call or shoot him an email to see what he has to say
 

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tripp george knows whats up, listen to what he said. The afr's will work good with the rpm2, but the vic jr's with either a vic 5.0 or a tfsr will rip all over that setup if cammed right....
 

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well, if youd ask me, for a street car the 185's will do the job, and would provide better throttle responce in the lower RPM range, the afr 186's and the comp cams 274 XEHR would make for quite a nasty street machine, and would work with your current intake quite well, and would still be streetable, for a more radical pro street type car, I would chose the victor JR's and the victor 5.0 intake, with a cam with something like 300/306 ADV duration, and a tighter lobe sep, like 108 since you would be pulling from 4000 up, so basicaly you need to determine the intended use of the car before any definitive answers could be given, Im not an expert...Im not even the best mech, I am however the the can of whooop Azzzz that gets delivered to many,many chevy owners....:)
 

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Discussion Starter · #15 ·
Well I started this thread and I am staying with the Edelbrocks, I have called Ed Curtis and he is making me a cam as a matter of fact it should be here today. He liked the RPM II and that was good enough for me, you see, some of these parts were purchased before I called him. I already had the intake and heads, He told me to get the AFR's if I didn't already have the Victors, but I did, so I planned on keeping them. I saw a post where somebody wanted to buy a set of Victors and I thought if I could sell the Victors and maybe buy the AFR'S, you get the idea. I have given up that idea since reading your responses to this thread and appreciate the help, besides my cam is profiled to fit the Victors but it sounds like the heads are very similar in flow numbers.
 

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Eddiehaskell - what part of WI are you in...im by Lacrosse
 

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Discussion Starter · #17 ·
I'm around Appleton, I saw the Sparta. I used to drive past there when I went west. Hey I was checking some other threads and saw you replaced your hood send me a mail I'd like to discuss "things" [email protected]
 

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You'll be glad you had Ed spec your cam.....it should make some nice numbers. I went with a set of AFR 185's and tfs-r intake for my 347....but I got them used for a great deal...so that's what I went with.
 

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I run box stock victor jrs on a stock compression short block with a anderson n 91 cam and it doesnt fall out off the tree it wheelies out and makes 388 rwhp and 330 rwt and goes 122.You will love the jrs they make great power and torgue even on a 302.I am also building a 347 and using the same top end from the 302 and I am expecting over 425 with matching torque at the wheels and mid to high tens hows that for versatility in a cylinder head.The afrs are good but for the money you cant beat the jrs for the power per doller.
 

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n8s_stang said:
I don't think the 185's outflow the Jrs stock for stock. Jrs have another 25cc on the intake port and flow something like 285 and 225 out of the box.
With all due respect (not picking on you personally), you're judging head flow performance the same way that most people do...by peak flow potential. However, the comparative, AVERAGE flow of any given heads throughout the lift range is far more important to power and performance than the peak number. In fact, the mid-lift numbers are MORE important than the PEAK numbers. That's because the valves spend far more TIME at mid-lift openings than they do at peak openings.

On every camshaft revolution, the valves move through the low and mid-range lift on the way to peak lift, and then back through the mid and low lifts on the way to closing. In other words, the valves spend a lot more time in the low and mid-lift ranges than they do at peak lift. Understanding that, look at the comparative specs of these heads (from the Edelbrock and AFR web sites, respectively). CFM flow, intake/exhaust, at various valve lifts:

.200" lift
Vic Jr: 127/108
AFR 185: 129/118

.300" lift
Vic Jr: 186/140
AFR 185: 189/153

.400" lift
Vic Jr. 234/167
AFR 185: 234/178

.500" lift
Vic Jr: 268/189
AFR 185: 267/185

.600" lift
Vic Jr: 291/195
AFR 185: 277/191

Now, looking at these numbers and understanding that the valves...at ANY engine rpm...spend more time below .500" lift than above, which heads do you want?

Even these flow numbers don't tell the MOST important part of the story, and that's flow velocity at the cfm volume delivered. Acoustic supercharging is a primary key to performance in any naturally-aspirated engine. The Edelbrock heads require 210cc of port volume to deliver LESS AVERAGE flow volume than the AFR with 185cc port volume. Which heads, then, do you think have the flow VELOCITY to beef up volumetric efficiency and cylinder filling at any rpm below 6500-7000 rpm? What percentage of the hours your 347 is running will it be running between 6500-7000 rpm?

If you're drag racing with a T-5 transmission and shift at 6500 rpm, you're going to drop back to about 3765 rpm when you hit second, 4456 rpm when you hit third, and 4887 rpm when you hit fourth. Which heads are going to pull you harder down the strip through these primarily mid-rpm ranges? AFR, hands-down.

For a street strip car the Viccy's are the choice, for a street only car 185's would offer more torque (which you don't really have to worry about with the added cubes).
I'd use a well-ported set of Vic Jrs. on a strip-only 347 race car; they'd beat the AFR 185s by raising the effective rpm range high enough to utilize the additional flow. Also, the mid-lift numbers of the Edelbrock's can be improved with professional (expensive) porting. For what it's worth, the Vic Jr's should be compared to the AFR 205 for a racing effort (210cc intake versus 205cc intake). The choice then gets harder.

I also don't agree that you "don't have to worry about torque." Torque is the ONLY thing that moves a car...period. We all love to talk about peak horsepower (me, too). However, street, race, or any other application, torque determines acceleration. Torque is an actual, measurable, twisting force. Horsepower is only a mathematical equation, multiplying torque by time. By gearing a car so that you can keep the engine screaming at maximum rpm most of the time, you CAN beat the performance of a high torque motor...simply because the gearing increases torque at the axle. But are you REALLY going to scream the engine around at 80%+ of red-line all the time? Or are you going to run around in the mid-rpm ranges most of the time? With a 6000-6300 rpm rev limit suggested by the rest of this combination, the AFR 185 will run off and hide from the Vic Jr's.

A CHP Street Fighter short block was suggested, which makes me think of compression ratio in the 10 to 1 range and a hydraulic roller cam. FWIW, not only would I choose AFR 185 heads, I'd go milder with the cam than the suggested 234/240. Maybe something in the upper- 220's range @ .050". Such a 347 will give you great performance with a 6000-6200 rpm limiter. BTW, I like the rest of the components that were chosen for this combo. I even like the 1-5/8" headers...you'll give up just a bit at max rpm but you'll love the brutal pull throughout the fat part of the power band.

Steve A.
 
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