[71 chevy]

they dont particularly flow well,
they have small ports,
stock exhaust location,
and the exhaust/intake ratio is quite bad,

yet, Bob West, Creeper72, and now 46872chevelle and Sinister have shown that this modest head is more than capable of bringing the hammer down, often besting bigger, better flowing heads

theories? hypotheses?

 

[Sinister]

Don't forget me!

Seriously though. I was going to get the AFR's and like you said I went with known combo's. Robb and Bob both running great. They seem to have great street manners.

 

[71 chevy]

Don't forget me!

Seriously though. I was going to get the AFR's and like you said I went with known combo's. Robb and Bob both running great. They seem to have great street manners.

I didnt realize you are running the Race rites too. care to give a breakdown of your combo?

 

[71454Chevelle]

they dont particularly flow well,
they have small ports,
stock exhaust location,
and the exhaust/intake ratio is quite bad,

yet, Bob West, Creeper72, and now 46872chevelle and Sinister have shown that this modest head is more than capable of bringing the hammer down, often besting bigger, better flowing heads

theories? hypotheses?

I'd say almost 350 cfm out of a 270cc port is pretty good! :yes:

 

[creeper72]

they dont particularly flow well,
they have small ports,
stock exhaust location,
and the exhaust/intake ratio is quite bad,

yet, Bob West, Creeper72, and now 46872chevelle and Sinister have shown that this modest head is more than capable of bringing the hammer down, often besting bigger, better flowing heads

theories? hypotheses?

My back yard theory is great velocity for there intended range.They may not show alot of air on a bench, but they move air efficently.
They also have great throttle response and are an easy way to put a pump gas 454 in the mid tens easy with a roller. I am sure some pro's can give you the real answer , but thats how it works in my head.

 

[creeper72]

Here is a basic breakdown on my budget build:

Brodix RR Ovals 270 non cnc ported (cheaper version)
454 2 bolt block bored 60
Stock cast crank
Eagle SIR I Beam Rods Bushed with 7/16 ARP cap screws
Mahle Pwr Pak pistons & rings 28cc dome coated part #BBC645310D28
Clevite standard bearings
Melling std oil pump with shimmed spring (small washer)
UD harolds Grind from Custom Cams SFT
Johnson Lifters w EDM
Cloyes Hex-adjust Roller Timing Set
TrickFlow push rods
Milodon Hardened oil pump shaft
Moroso 7qt pan with built in windage & scraper
Team G single plane intake with 1/2" wood spacer
Holley HP 950
Team G aluminum water pump
MSD Pro Billet
Professional Products SFI Blancer
Cheap chrome pulley - stock replacements
B&M SFI Flexplate

I put this together myself and it could have been assembled with more detail.I pretty much checked P/V clearance, verified TDC ,verified cam ICL and used the old plasti-gauge for bearing clearances.
I did pay to have the Rot Assem. balanced.

 

[67Super Sport]

Brodix RR-O's here as well with a very small roller cam.

I think most guys that are using these heads with success are doing it with torque. Most are under 7000 rpm combos or barely over and they are choosing this head based on this RPM goal and taking advantage of the excellent port velocity they offer at these RPM's. These heads flow very well for a 270 cc intake port and it would take a very well ported set of GM irons to match them. Like what was already said think port velocity and lots of it.

 

[cv67]

Because there are super well flowing heads out there that substantially raise the bar doesnt mean one that flows less is "bad".

I agree with the rpm/torque statement above.

 

[40Coupe]

I don't run a particularly large head on my 468. If you want to ET in a heavy car you need to 60 foot and a small high velocity port lends itself well to this.

If you want one of these heavy Chevelles to go quick it all starts at the starting line.

 

[dadeo-3]

I am in the 10'50's with them in my 427 powered Camaro (see video in my signature). They just work well with my combination. Frankly, they would work better if I wasn't so over-cammed (287 @.050!!).

 

[Sinister]

I think most on here thought my car was over cammed but car seems to be running really well. Here is my combo. Of course this is the third motor in a year but this one really seems to have it together. Power is not an issue and at some point I plan to spray a 100 or 125 shot.

496
Brodix RR Ovals CNC 115's
Comp Cams Solid Roller 262/272 @.050 .714/.734 lift
Vic Jr. Slightly ported 1" spacer
BG 850 E85 self built
2" Ceramic Coated Headers
Scorpion Roller Rockers
Isky Needless lifters
Forged Scat Assembly
H-beam Rods
JE 13.1 Pistons
BTE 4500 Stall
TH350
12 bolt 4.10 gears 33 spline axles, Full spool, all Moser
UMI adjustable uppers
UMI boxed lowers
UMI relocation brackets (on top hole)
Hrparts Rear Anti Roll bar
Afco Rear shocks (haven't mounted yet)
Santhuff front springs (haven't tested yet but are mounted)
28x10.50 ET Drags (haven't tested yet)

I think that about covers it.

 

[40Coupe]

You are not over cammed at 13:1. That combo has 9's written all over it.

 

[Sinister]

That is what I am shooting for. I am not patient as you can tell but I am trying like hell to get there. I figure it will take a 6.40 pass to achieve it. My car is more set up for the 1/4 than the 1/8th I think. At least with the Vic Jr., 4.10 gears, etc..

 

[Bob West]

I had to run 6.27/6.28 to get there, but I dont have any compression

 

[Sinister]

I have a race in "running" that I am timing this weekend. It is fairly local so....if the weather holds up I am going to try and get my brother in law to monitor my "race" while I sneak out and hit test n tune on Saturday. Like you said Bob, my front end with the new Santhuff springs is awesome! I can move the entire front end up and down by hand very easy. That along with the new AFCO rear shocks, Moroso Trick Rear Springs, and slicks. My time has to end up dropping a bit. I think I can hit 104 mph this weekend and a 1.50 60ft for now. That should get my in the 6.6-6.7 range.

 

[71 chevy]

I'd say almost 350 cfm out of a 270cc port is pretty good! :yes:

328/216 at .600 is LOW compared to the more popular heads out there.

My back yard theory is great velocity for there intended range.They may not show alot of air on a bench, but they move air efficently.
They also have great throttle response and are an easy way to put a pump gas 454 in the mid tens easy with a roller. I am sure some pro's can give you the real answer , but thats how it works in my head.

I honestly dont even have an explanation - by almost any standard, they are too small even for a 454 so you probably have something there. the airflow is probably just optimized for a mid sized bbc

I am in the 10'50's with them in my 427 powered Camaro (see video in my signature). They just work well with my combination. Frankly, they would work better if I wasn't so over-cammed (287 @.050!!).

that's pretty stout for a 427 right there :thumbsup:

 

[71 chevy]

I don't run a particularly large head on my 468. If you want to ET in a heavy car you need to 60 foot and a small high velocity port lends itself well to this.

If you want one of these heavy Chevelles to go quick it all starts at the starting line.

hey, nice vids in sig. what heads are you running, and what is your suspension like?( I have a nova is why I ask)

I think you might be up to something as it seems most of the combos using the RRs do tend to 60' quite well

 

[Sinister]

I think you might be up to something as it seems most of the combos using the RRs do tend to 60' quite well

Except mine...but I am working on it! :thumbsup:

 

[71 chevy]

I think you might be up to something as it seems most of the combos using the RRs do tend to 60' quite well

Except mine...but I am working on it! :thumbsup:

lol, whats your 60?

maybe its time to try a dual plane intake (runs for cover)

 

[Sinister]

I have had a best 60ft of 1.59 on my ET Street Radials 30" tall in the heat of the summer with the track well prepped. Last week was my first chance with the new motor and it ran a best of 1.89. Not good, I know. I think once the track gets more prep with less street cars the 60ft will improve. However, if the weather holds up this Saturday and I can sneak off for an hour I think I will run a new best. Here are the recent changes to help improve 60ft.

1. Front Santhuff 200lb springs
2. Afco Rear double adjustable shocks
3. New Rear Springs, just not sure which ones yet.
4. And the most important change. Slicks! 28x10.5x15 ET Drags.

My front end moves very easily now so I am very hopeful to hit a 1.50 60ft on Saturday and a 6.6 or 6.7 1/8th at 104 mph. We'll see.