AFR or Vortec heads? Cam? - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 10-25-2005, 01:27 PM
rodent's Avatar
Garage Pimp
 
Join Date: Oct 2005
Location: Highlands Ranch, CO
Posts: 10
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
AFR or Vortec heads? Cam?

Found a complete virgin 400 SBC for $75 that I'm going to build for my custom K5 Blazer 4x4. The Blazer is mostly used for the rocks but I like to run it on the street and still have it power up the mountain passes while passing everyone on 38" tires. The drivetrain is pretty beefed. I'm using a 4L80 trans, and 1 ton axles.

I'm trying to keep this engine on a tight budget but one thing I don't want to skimp on is the heads. Scoggin Dickey offers some Vortec's that are machined to accept larger cams and the Edelbrock Vortec manifold for $900 or I can get a set of new AFR 195 heads for $1200.

I'm leaning towards the AFR heads. I already have a performer manifold that will fit my 400 SBC with standard SBC heads. I know I will have to drill the steam holes.

What do you guys think?

Also, any suggestion on a good cam to use in the 400 sbc?

http://www.sdpc2000.com/catalog/2172...mer-Intake.htm
Our Vortec cylinder head kit provides you with everything you need to install the new Vortec heads on your vehicle. The following kit includes assembled Vortec heads, head gaskets, GM head bolts, GM stamped steel rocker arms, intake manifold, intake gaskets, 12 point intake bolts and additional required components as stated. This kit features our upgraded Vortec heads which have been modified to accept our high performance Z28 valve springs with lightweight LT4 retainers. This produces a high reving cylinder head that can handle up to 0.525" lift hydraulic camshafts. An Edelbrock Vortec Performer intake manifold is matched with this kit for optimum performance.

http://www.airflowresearch.com/pages/195sbc_sh.htm
The AFR Emissions Legal (versions from 1969-94 with heat riser, CARB EO #D-250-2), 195cc intake port small block Chevy cylinder heads are available in your choice of straight or L98 angle plug versions. These heads feature a 74cc or 68cc combustion chamber with a 64cc exhaust port and a 3/4” thick head deck (ideal for nitrous or blower applications). The 68cc chambers are designed for flat top or dished pistons; domed pistons will require additional machining. Standard valves are 2.020 intake and 1.600 exhaust with AFR’s hardened ductile iron interlocking valve seats. The exceptional flow characteristics, ideal operating range of 2000 rpm to 6500 rpm, 23º valve angle, and standard valve spacing make this the perfect street head for 350 cid to 400 cid engines from 1955-86. Available for 1987 to present engines with center bolt valve covers and 2 center intake bolts at 72º angle. No special parts are required.




http://www.chevyhiperformance.com/te...38/index1.html
Quote:
When comparing cylinder-head flow data, it seems that everyone always looks at the maximum-lift flow data. But especially for street engines, the smarter move is to look at the mid-lift flow numbers. We decided to look more closely at the more popular iron and aluminum small-block heads at the 0.300-inch valve lift. Why 0.300-inch valve lift? According to knowledgeable engine gurus like the late Smokey Yunick and Zora Arkus-Duntov, concentrating on valve lifts at 65 to 68 percent of maximum valve lift contributes to both a strong overall torque curve and good horsepower. Number crunching 65 percent of 0.480-inch valve lift equals 0.312 inch.

We used this information to evaluate several small-block cylinder heads that we’ve flow-tested over the last four years. Since many of the heads that we tested used varying intake-valve sizes (from 1.94 to 2.08 inches), we multiplied the circumference of the valve (diameter times 3.1417 (pi)) times the valve lift to create a square inch area “flow window.” Then we divided this valve window area by the flow at 0.300-inch valve lift. By doing this, we eliminated the variable of valve diameter by creating a flow- per-square-inch criterion.

Here’s how this works using the GM Performance Parts Vortec iron cylinder head. The Vortec head uses a 1.94-inch intake valve to flow 190 cfm at 0.300-inch lift. We multiplied 1.94 inches times pi = 6.094 inches of circumference. This figure times the valve lift equals a flow window area (6.094 x 0.300 = 1.828 square inches). Then we divided the flow by the area (190/1.828 = 104 cfm per square inch). This number by itself really doesn’t mean much. But when we compared over 15 cylinder heads using this evaluation, the Vortec ranked fourth overall. This is just further reinforcement for how well this cylinder head flows between 0.100 and 0.400 inch of valve lift.

The following list includes the top 15 cylinder heads that flowed the best when averaged between 0.300 and 0.400 inch of valve lift. We should also state that all of these heads perform well. Should this mid-lift flow data be the only criterion for choosing a cylinder head for a 350ci/450hp street engine? The simple answer is no because it’s dangerous to base a decision on only one data point. But we would certainly encourage the use of this information as part of an overall decision on your next set of cylinder heads. Our lawyer has also advised us to say that your mileage may vary and the secretary will disavow any knowledge of our actions should we be caught. So there.

The 300 Club
1. AFR 190
2. Canfield 220
3. Canfield 195
4. Vortec iron
5. AFR 180
6. AFR 210
7. TFS 195
8. Holley 300-570
9. World Sportsman II 200
10. Dart Iron Eagle 220
11. Edelbrock Performer RPM
12. World S/R Torquer
13. Brodix -8
14. Stock 882 iron
15. Edelbrock Victor Jr.

    Advertisement

Last edited by rodent; 10-25-2005 at 02:28 PM.
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 10-25-2005, 02:09 PM
347mustang's Avatar
Member
 
Last photo:
Join Date: Apr 2005
Location: oklahoma
Posts: 389
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
did you mean afr 205???? the afr are nice but they are a pretty high rpm head with the big 205 cc runners, and on a 4x4 you need low end power not hig top end power, you could build it and it would not prefor like you wanted to where the vortec would more better suited for low end power and still have nice top end if you needed it and the same goes for the cam , use to big of a cam and the 4x4xwill not be happy , 4x4x's like low end power and cams will make the difference in it, combine a big cam with a big set of afr heads and it will be soggy at any thing under 5000rpm, maybe try the vortecs with a extrem 4x4 cam from comp
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 10-25-2005, 02:39 PM
rodent's Avatar
Garage Pimp
 
Join Date: Oct 2005
Location: Highlands Ranch, CO
Posts: 10
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by 347mustang
did you mean afr 205???? the afr are nice but they are a pretty high rpm head with the big 205 cc runners, and on a 4x4 you need low end power not hig top end power, you could build it and it would not prefor like you wanted to where the vortec would more better suited for low end power and still have nice top end if you needed it and the same goes for the cam , use to big of a cam and the 4x4xwill not be happy , 4x4x's like low end power and cams will make the difference in it, combine a big cam with a big set of afr heads and it will be soggy at any thing under 5000rpm, maybe try the vortecs with a extrem 4x4 cam from comp
Sorry... typo. I meant the 195 AFR heads but I could also get the 180 AFR's too. The Vortec's size are 170. I thought maybe 195 would be okay for for a 406ci engine for low-mid RPM use.

I was looking to do this build and build a high torque engine but also have some good HP at the upper end:
http://chevyhiperformance.com/techar.../148_0306_406/


Maybe I should stick with the Vortec's.

Here's a pic of the K5 back when it had a 496 rat:
http://home.comcast.net/~k5shawn/k5.jpg

Last edited by rodent; 10-25-2005 at 02:58 PM.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 10-25-2005, 04:41 PM
firestone's Avatar
http://teamrfc.gospelcom.net
 
Last photo:
Join Date: Nov 2003
Location: Fenton MI
Age: 32
Posts: 1,743
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
If you have the money for the AFR's I would go with them hands down. The Vortec heads are great for the money, but the AFR's are far superior. As far as the size goes, I would go with the 180's in a truck like you are talking about. It will be a torque monster. One thing to think about with the vortecs is that they tend to crack if they are overheated whereas the thick castings of the AFR heads will be much less apt to.

Here is an interesting article

http://airflowresearch.com/articles/article39/A-P1.htm

Adam.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 10-25-2005, 08:27 PM
tornado-tech's Avatar
Member
 
Last photo:
Join Date: Aug 2004
Location: Kansas
Age: 47
Posts: 320
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Since you said the truck will be in the rocks, I would get the vortecs. You will be after as much torque as you can get since rock crawling especially with the weight of 1 ton axles and 38's, you will need low-end torque. The AFR's are an excellent head but will move your powerband up. That is not what you want in the rocks.
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 10-25-2005, 09:54 PM
Member
 
Last wiki edit: Vacuum brake bleeder set up
Join Date: Nov 2003
Location: So Cal
Posts: 1,245
Wiki Edits: 8

Thanks: 0
Thanked 0 Times in 0 Posts
Go with the AFR's if you have the money. Gearing is where you get the low end torque from... 5.13's is what you want with those tires and OD.

I have a '71 K5 on 1-tons and 36's with 4.56 gears. You have OD and bigger tires...you need more gear!
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 10-25-2005, 10:00 PM
lluciano77's Avatar
Short changed on common sense
 
Last photo:
Join Date: Jun 2003
Location: california
Age: 37
Posts: 3,548
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Is everyone loosing site of the fact that the freakin' Vortecs are $900???

Man, you couldn't pay me enough to by a set of Vortec heads for $900 bucks.

If I found out one of my friends paid $900 for a set of Vortecs, I'd have to shave their butt and teach them to walk backwards.

Get the AFR heads. 400s like a lot of flow. The 195s will work fine. I have a set of 200cc Sporstman IIs on my 400. They are ported to the moon on top of it. I have more bottom end than I know what to do with.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 10-25-2005, 11:31 PM
Blazin72's Avatar
You got a leaky spark tube...
 
Last wiki edit: Rearend removal
Last journal entry: General Lee
Last photo:
Join Date: Jul 2005
Location: Union, WA
Age: 32
Posts: 2,868
Wiki Edits: 19

Thanks: 0
Thanked 2 Times in 2 Posts
I would have to agree with the AFR crowd. If youve got the money, go with em. If youre looking for low end grunt you may want to go with the 180s. According to the link below they'll flow 250 cfm intake and 208 cfm exhaust at .500 lift. By comparison the Vortecs flow 239 cfm and 160 cfm at .500 lift.

You can sift through these to help you make your decision. http://www.carcraft.com/techarticles/116_head_chev/
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 10-26-2005, 09:25 AM
Registered User
 
Join Date: Nov 2004
Location: California
Age: 67
Posts: 831
Wiki Edits: 0

Thanks: 28
Thanked 23 Times in 20 Posts
You also asked for cam input. I think you need to make a cylinder head decision first. Here's why. The AFRs flow VERY well on the Exhaust side, producing a very high E/I flow ratio. They work very well with single pattern cams. Just about any other Chevy head works best with a dual pattern cam (that's why so many Chevy cams are dual pattern . . . . . ) Using the AFR heads, and looking for a particular type idle quality and performance curve, you can increase the Intake side's duration some (as well as the exhaust's) and still maintian the same overlap and LSA you'd have with a smaller intake lobe on a dual pattern cam. Is that confusing?? It sounds confusing to me. Think of it this way. Overlap has a lot to do with idle quality. Overlap is a function of LSA and the sum of the Intake and Exhaust durations. So, if you use a single pattern (reduced Exhaust duration) cam you can take some of that exhaust duration that you didn't use and apply it to the intake side. Thus, you get a longer intake event. And an adequate Exhaust event. An exhaust event that might not have been adequate had you had a poorer flowing exhaust port. When purchasing a cam, this is good to know, because some companies will custom grind a cam (using their standard lobes, but with custom lobe combinations and custom lobe orientation) for you. Some will even do it for free. So, you can get just exactly what you want. I bought a Comp Hydraulic Roller for my 383 a few years ago. I ordered single pattern (two identical lobes) because I'm using AFR heads. So, I was able to slightly increase the intake duration, and select the LSA I wanted. Have fun!!

Pat
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 10-26-2005, 11:23 AM
USA1's Avatar
Member
 
Last photo:
Join Date: Apr 2003
Location: Indiana
Posts: 177
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
lluciano77 The vortecs come with heads,intake,rockers,head bolts, gaskets and other hardware. I realize you don't care for vortecs, but that price is not bad for all that you get.
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 10-26-2005, 02:15 PM
rodent's Avatar
Garage Pimp
 
Join Date: Oct 2005
Location: Highlands Ranch, CO
Posts: 10
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Thanks for all the replies!

Yeah, 900 is the complete Vortec kit from sdpc. Includes machined heads, different springs, and manifold. New Vortec heads are under $500 I think (not machined). Hard to beat that cost if you didn't have a high lift cam but you still need the special manifold.

I called AFR and talked to Dave which was really helpful. He acutally suggested the 195 heads for a 400 SBC even for low RPM use. True, the torque at idle will be a little less but its still well over 300 ft lbs. I'm running 4.88 gears with a Doubler (4:1) transfer case so I really don't need a ***** load of torque down low. I'd rather have the power at the upper RPM if I'm trying to make it up something steep where I need lots of wheel spin and high RPM to get me up. I also want the power on the mountain highways when I'm passing someone going up a steep grade. I figure my RPM will be 4000-5500 when doing so.

That article makes a great comparison too.
Quote:
After a few pulls, the AFR cylinder heads with 180cc intake runners made nearly the same amount of torque as the original configuration (Vortec heads), but it did so 700 rpm higher in the power curve, adding 49 hp to the best Vortec dyno run. Remember, these gains came from a motor with less compression
49 hp with less compression? Damn!

Thanks for the cam info too. That will be helpful selecting the proper cam.
Reply With Quote Quick reply to this message
  #12 (permalink)  
Old 03-04-2009, 10:11 PM
done learning, done living
 
Last photo:
Join Date: Feb 2009
Location: Middle of the Mitten
Age: 29
Posts: 1,698
Wiki Edits: 0

Thanks: 158
Thanked 89 Times in 80 Posts
$1200.00 go for the brodix heads. b in brodix =best. afr heads to me are overated. but that is just me. For rock crawling I would go with the vortec heads but i would choose the dart ss heads over the gm vortecs. remember intake runner size is the most important thing when choosing cylinder heads and a little to small is better than a little to big. you want the intake runners full of gas and air all of the time to make good torque and power
Reply With Quote Quick reply to this message
  #13 (permalink)  
Old 03-05-2009, 03:05 AM
curtis73's Avatar
Hates: Liver. Loves: Diesel
 
Last wiki edit: How to find cheap parts
Last journal entry: Found an LQ9 today
Last photo:
Join Date: Dec 2005
Location: Carlisle, PA
Age: 41
Posts: 5,186
Wiki Edits: 16

Thanks: 7
Thanked 9 Times in 6 Posts
Do yourself a favor. Find a target hp. Then find the flow you need to achieve that HP. Then find a group of heads that fit that flow profile and choose the one that has the smallest intake port volume.

Flow makes HP, small port volume makes velocity which equals torque. In a 4x4 rock climber/street truck, you shouldn't care about anything above 4500 rpms, unless you want to cripple rock climbing ability in favor of bragging rights. This isn't mudbogging or monster trucking.

Vortecs flow as much or more as most entry-level aftermarket 190cc heads and they do it with 20cc less intake port volume and about 1/3 the price. Be realistic. If you're not revving the engine to the sky, you don't need more than the .470" lift from vortecs anyway.

This website is not gospel, but it is your friend: http://users.erols.com/srweiss/tablehdc.htm

i also agree with the others... $900 is too much for vortecs. I had a set of ported, rebuilt vortecs with springs/retainers for .550" lift that I just sold for $475. They are for sale remanufactured all over the web for $300-$450. They are available already modified brand new for something like $675

Last edited by curtis73; 03-05-2009 at 03:13 AM.
Reply With Quote Quick reply to this message
  #14 (permalink)  
Old 03-05-2009, 06:33 AM
Registered User
 
Join Date: Dec 2008
Location: New Jersey
Posts: 616
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Quote:
Originally Posted by crussell85
$1200.00 go for the brodix heads. b in brodix =best. afr heads to me are overated. but that is just me. For rock crawling I would go with the vortec heads but i would choose the dart ss heads over the gm vortecs. remember intake runner size is the most important thing when choosing cylinder heads and a little to small is better than a little to big. you want the intake runners full of gas and air all of the time to make good torque and power
I agree. Someone mentioned exhaust flow above... exhaust flow is really an irrelevant number. There's 900HP+ motors making that power with less than 250CFM on the exhaust side. In your application, meaningless.

Also, the question is for the delta in price the Vortecs can be worked. IMO for YOUR APPLICATION keep the money in your pocket.

Don't get all wrapped up in flow numbers, there is far more to a head than flow numbers.
Reply With Quote Quick reply to this message
  #15 (permalink)  
Old 03-05-2009, 12:42 PM
Registered User
 
Join Date: Feb 2009
Location: orlando
Posts: 204
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
both heads are a good deal, i used those vortec heads on a 400 they are torquey, but when you look at afr's dyno results on their website, you'll just want them even more. if you have the money, get the afrs, you'll be glad you did...excellent mid-flow lift numbers!!
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Camshaft for vortec heads Leon Weathers Engine 3 11-19-2004 11:02 PM
heads?? cam??? J327HO Engine 4 10-24-2004 12:52 AM
XE 268 or XE 262 with Vortec Heads Chevy21 Engine 3 09-06-2004 10:38 AM
AFR heads? dk01_99 Engine 14 07-19-2004 10:46 PM
vortec heads rpainter87 Engine 1 03-17-2002 01:09 PM


All times are GMT -6. The time now is 01:30 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.