How much Flow can you get with a stock intake port

[GoFast.....]

I am putting some things together for this 107 and I am wondering just how much flow at 28 inches you can get out of a Stock ported head with keeping the stock intake port at 1.640 JET Clams they can flow 257cfm @28 inches from a modified stock TB http://www.johnsonenginetechnology.com/JETPAGES/parts/twin-cam-throttle-body.html The 1.94 flows pretty well but I wonder if a stock head can flow anything bigger efficiently

[Don D]

How much CFM does your motor need?

[hdtuner23]

257@28  Thats w/ both ports, tell them you want flow #s w/ 1 port blocked off.  Unless that is you have 1 of them single cyl. motors.Far as I know the cyl heads only work individually!!!

[mayor]

gofast, I remember Larry Hardy posting some data last year on the '06 heads where he was able to get 246@25" at .550 with a 1.9" intake w-port and bowl work (260@28").

[hdtuner23]

Just stating that half the information is never enough. Converting to 10 in. by the way would be a multiplier of .598. Or 153cfm @10. Stating that JET never tells how their manifold is tested other than @28. By the way a 06 46mm w/ a stock port 1.61. flows 159cfm @10. or 265 @28. 1 port open! HMMMM

[GoFast.....]

that is with one intake port. Has anyone ever posted some flow numbers with 1.94 valves

[Admiral Akbar]

R&R cast Heads with 1.94 Intake and 1.625 Exhaust valves (THESE HEADS ROCK)
Intake
· @ .100 = 38.6
· @ .200 = 80.2
· @ .300 = 114.5
· @ .400 = 141.5
· @ .500 = 157.3
· @ .600 = 167.8

Exhaust
· @ .100 = 29.8
· @ .200 = 62.2
· @ .300 = 89.3
· @ .400 = 110.6
· @ .500 = 112.7
· @ .600 = 114.1

The note ain't mine

[GoFast.....]

R&R cast Heads with 1.94 Intake and 1.625 Exhaust valves (THESE HEADS ROCK)
Intake
· @ .100 = 38.6
· @ .200 = 80.2
· @ .300 = 114.5
· @ .400 = 141.5
· @ .500 = 157.3
· @ .600 = 167.8

Exhaust
· @ .100 = 29.8
· @ .200 = 62.2
· @ .300 = 89.3
· @ .400 = 110.6
· @ .500 = 112.7
· @ .600 = 114.1

The note ain't mine

Did you include the price Max and what size of intake port is this. m ust be at 10in.

[Admiral Akbar]

that is with one intake port. Has anyone ever posted some flow numbers with 1.94 valves

All you asked for was numbers..

Pretty sure the intake port is bigger..

The 1.94 valve size is not the limiting flow factor with 1.63.

The port diameter (and design) is..

If you have to ask the price, they're too expensive..   
(don't know, BTW)

Max.

[Deye76]

R&R cast Heads with 1.94 Intake and 1.625 Exhaust valves (THESE HEADS ROCK)
Intake
· @ .100 = 38.6
· @ .200 = 80.2
· @ .300 = 114.5
· @ .400 = 141.5
· @ .500 = 157.3
· @ .600 = 167.8

Exhaust
· @ .100 = 29.8
· @ .200 = 62.2
· @ .300 = 89.3
· @ .400 = 110.6
· @ .500 = 112.7
· @ .600 = 114.1

The note ain't mine

Did you include the price Max and what size of intake port is this. m ust be at 10in.

Yes, "10in."

[KingofCubes]

This R&R head is with a 1.900 intake, 1.625 exhaust at 10"'s. What is even better about this head is the velocity.

[POORBOY]

This R&R head is with a 1.900 intake, 1.625 exhaust at 10"'s. What is even better about this head is the velocity.

What are the FPS velocity numbers on these heads,[ short turn,middle ,top,] that would be interesting.

[KingofCubes]

Those heads were tested at the lab at Dartmouth. Tested at 150"'s of depression and held between 675 -720 fps at any given lift.

[POORBOY]

Those heads were tested at the lab at Dartmouth. Tested at 150"'s of depression and held between 675 -720 fps at any given lift.

Dam, that's haul'in ass, would that be somewhere around 300-370 FPS @ 28 inch

[GoFast.....]

Those are 725.00 a peice heads and puts them in the class with everyone elses supercast heads. I would think we would have some guys on HTT that could post some 1.94 stock ported head flow numbers

[wfolarry]

To run a 1.940 valve you really need to change the seat. That's probably why you don't see more of it. I ran a 1.940 with a Super G & the ports opened up to match the S&S manifold. It flowed good. I don't save flow sheets or I would post it. Those flow numbers you see from the R&R head are easy. The hard part is in the mass flow that the test at Dartmouth proved out. While my bench won't pull 150" it can pull over 40" & you'd be surprised at the things you find wrong when you crank up the pressure. A head that looked good at 10" can look like "Potty mouth" at 40". Some guys use small benches & convert their #'s to a higher depression but testing at those higher #'s might reveal a flaw that you otherwise wouldn't see. It's all in the details.

[Don D]

I wasn't trying to be a smart ass. How much do you need to achive your goal? There are heads to be had with a phone call that will far exceed these R&R heads for airflow on a test bench. Ports and valves as large as a sewer main. If the R&R heads are too $$ much how many $$ do you want to spend? There is a point of diminishing returns if airflow is going to be singled out as the milestone, and aftermarket looks better. I wrote a long comment on the Vizard thread and told my thoughts on a similar topic.
I have achieved similar results to the R&R head and put them on bigger motors (113"). I test at 28" and probe velocitys at up to 48" but that is not really a complete story or the best of breed heads won't necessarily fit the build you propose. Also test fixtures and other bench specific idios can give results that are not real conducive to comparasion against others unless they use exactly the same setup.
These builds just don't work well usually when an end user picks a group of "best" parts. The head porter, tuner and builder all can help make good decisions regarding the "best" parts. If a guy is doing his own work the tuner and head porter suffice. Pick those well and put the motor together right and it will work well. The "best" parts are the sum as a collective group and this includes how the bike will be tuned and with what software and hardware.
A little food for thought
http://www.rehermorrison.com/techTalk/16.htm

[PanHeadRed]

Go fast I have measured Zippers CNC (stock casting) head flow 270 CFM (actual was 269.8 cfm) lift was .7" @ 28" I did not have the opportunity to measure the port. I believe the intake valve was 1.9"

257CF from 1.64 (if I am interpreting it correctly) is more then reasonable for a stock casting.

And I would not doubt for a second the 270+ CF from the R&R.

Larry, I would be very interested in seeing the flow numbers from the 1.94" intake if you can locate them. If you can't would you post/email from your best memory?

[Admiral Akbar]

I know that early CNC Zippers heads have a 1.63 intake port, I've heard that the later ones have bigger ports.. If you look at Munkey's carb shoot 3, a stock SE manifold only flows 154 cfm at 10 inches... I have trouble believing a bored out FI can pull say 257 @ 28 x sqrt (10/28) =  154 cfm @10.. Track length is a bunch longer and it's got a butterfly. The 45 on a 1.7 se manifold pulled 154.. So the FI with butterfly is as efficient as a 45?

Max

[ederdelyi]

Before I leave for my "northern retreat" I'll throw this out for the "flow junkies" to chew on:

Flow and velocity reports at the various depressions are without a doubt a good measure of the efficiency of the component and I won't argue the use of them as a figure of merit.

But, and IMO,it's a big but, (no, not your SO's) why is it that no one seems concerned about anything other than what these things will do at what amounts to WFO operation? How much air and at what speed is that air flowing at 1500 - 2500 RPM which is where most say they want their power? Airflow and port speed isn't constant in a running spark ignition, throttled engine... at least not in any I've ever worked with. So why is it that all the folks who say they want low end grunt are only looking at what this stuff will do WFO?

Y'all have fun and if I don't get back on the forum before the reindeer crap on yer roof ... Merry Christmas and Happy New Year!

[Faast Ed]

.... before the reindeer crap on yer roof ...

I love this guys way with words!!!  LOL

Have a safe and happy Holiday Ederdelyi. 

[PanHeadRed]

Max, if you asking me about the TB flow I can't answer, I am already confused enough about the original question, I guess I can't really tell if he is asking about flow from a stock head casting or the throttle body.

[PanHeadRed]

>So why is it that all the folks who say they want low end grunt are only looking at what this stuff will do WFO?<

Ed I will admit I do not have all the answers, but I am one of those guys who does not limit my rides to one fourth of a mile at a time.

I consider a race from Baltimore to Daytona and back a better measure of a bikes worth.

MFC/HFN

[wfolarry]

>So why is it that all the folks who say they want low end grunt are only looking at what this stuff will do WFO?<
Here's a few..........
Bragging rights.
Sitting at a bar showing your friends that your bike made more power than theirs.
Gotta have something to show for all that money wasted.
Never go farther than the next bar.
Trailer their bike to all events.
Think the burnout pit is cool.

[Deye76]

>So why is it that all the folks who say they want low end grunt are only looking at what this stuff will do WFO?<

Ed I will admit I do not have all the answers, but I am one of those guys who does not limit my rides to one fourth of a mile at a time.

I consider a race from Baltimore to Daytona and back a better measure of a bikes worth.

MFC/HFN

That's my definition as well.

When Ed said many want low grunt @ 1500-2500rmp, I almost choked. If I'm at 1500rpm I best be in 1st gear, accelerating, not in 3rd + trying to pass a truck.