Superflow 110.

10" of water.

74mm bore adapter

No valve

Lift in Inches Flow in CFM

N/A 60.59

Standard Port

Lift in Inches Flow in CFM

0.05---12.7---8.1

0.1---27.54---21.5

0.15---39.2---33.6

0.2---46.6---44.1

0.25--- 55.0 ---53.9

0.3---58.25--- 57.4

0.35---61.42---60.3

0.4---62.48---61.1

Standard port with 30* cut back valve

Lift in Inches Flow in CFM

0.05---13.6

0.1---24.2

0.15--- 41.5

0.2---52.7

0.25 ---59.5

0.3---59.1

0.35--- 58.6

0.4--- 58.6

Throat clean up and SSR Blend

Lift in Inches Flow in CFM

0.05 ---7.25

0.1---19.6

0.15 ---30.6

0.2 ---40.6

0.25 ---51.1

0.3 ---60.3

0.35 ---66.2

0.4 ---64.7

as above +

Cut back Valve

Lift in Inches Flow in CFM

0.05 --- 10.4

0.1 --- 22.5

0.15---36.4

0.2 --- 49.2

0.25 ---59.6

0.3 ---66.2

0.35 ---66.2

0.4 --- 64.7

As above +

Tapered valve guide and boss

Lift in Inches Flow in CFM

0.05--- 13.8

0.1 ---26.8

0.15 ---40.6

0.2 ---51.5

0.25 ---60.3

0.3 ---67.9

0.35 ---67.9

0.4 ---65.4

As above +

Open up Throat to 80-85% of valve size. Concave LSR

Lift in Inches Flow in CFM

0.05 ---13.25---12.9

0.1 ---26.26---26.8

0.15 ---40.3---41.4

0.2 ---52.1--- 53

0.25 ---62.15---61.4

0.3 ---67.25---68

0.35 ---65.8--- 65.8

0.4--- 65 ---65.4

As above +

small 30* top cut, 45* seat (1.2mm) 60* bottom cut

Lift in Inches Flow in CFM

0.05 ---14.8

0.1 ---29

0.15 ---41.5

0.2 ---54.2

0.25 ---62.5

0.3 ---66.9

0.35 ---64.7

0.4 ---64.7

As above +

Raise roof behind valve guide to 36mm at mouth tapering into boss area

Lift in Inches Flow in CFM

0.05 ---14

0.1 ---27.3

0.15---39.7

0.2 ---52.1

0.25 ---60.7

0.3 ---67.26

0.35 ---69.1

0.4 ---66.62

As above +

Remove Valve guide boss completely and open port (clean up casting marks etc)

Lift in Inches Flow in CFM

0.05 ---14

0.1 ---29

0.15 ---42.1

0.2 ---55.1

0.25 ---62.5

0.3 ---68.4

0.35 ---64.7

0.4 ---66.2

Edited 14 March, 201016 yr by varnish

Good work, you must of had a super awsome mate to help you with work like that.

Otherwise you'd never of regulated them results properly, you've gotta be handy with the steel if you know what I mean "Earn your keep".

Had a chance to go over the velocity data and draw up some simple pictures.

All the air speed figures are in feet per second

(5280 feet in one mile, 100 miles per hour = 146.666667 feet per second)

Measurements were taken at full lift and @ 10" of water.

Lift in Inches Flow in CFM

0.05 --------------------14.8

0.1 --------------------29

0.15---------------------41.5

0.2 -------------------54.2

0.25 -------------------62.5

0.3 -------------------66.9

0.35 -------------------64.7

0.4 -------------------64.7

The shape of the port is pretty standard here. The valve seat has been smoothed into the SSR, and valve guide and boss cut away at the sides and shaped into a teardrop. Back cut valve and 60* bottom cut on the valve seat.

Lift in Inches Flow in CFM

0.05 -------------------14

0.1 -------------------27.3

0.15--------------------39.7

0.2 -------------------52.1

0.25 -------------------60.7

0.3 -------------------67.26

0.35 --------------------69.1

0.4 --------------------66.62

The roof was raised to 36mm at the port mouth (100% of valve size), and tapered gently into the original port size at the valve guide. This had the effect of making a slightly more down draft approach to the SSR, which you can see has improved velocity at full lift. But seems like we miss out of some of the lower down flow in the port above.

Lift in Inches Flow in CFM

0.05 -------------------14

0.1 -------------------29

0.15 -------------------42.1

0.2 -------------------55.1

0.25 -------------------62.5

0.3 -------------------68.4

0.35 -------------------64.7

0.4 -------------------66.2

Here we've pulled back some of the low lift flow, but miss out at higher lift as I suspect the port is going turbulent.

You can easily see this with a pitot and a manometer as it will not pull a steady depression.

To flow more air through an orifice of a fixed size, the air speed must increase. If you increase the orifice size and the flow doesn't increase the air speed must have dropped.

So as the flow hasn't really increased, we lose some air speed in this port.

I hope some of you find this interesting or useful.

Haven't really had time to do a lot with this.

And I guess people aren't interested anyway, but I think its good to share information as it might interest someone.

I've put a 36mm valve in the AAU and done some throat work.

The flow at high lift is suffering because of the small port size.

But you can see it's much stronger in the mid range and I expect to keep the strong flow here and improve flow at higher lift.

When I get time I'll open the port up and do some more tests. I'm hoping to hit 75CFM @10" with this head.

That would be a 20% increase in flow at 0.4" over the standard AAV head.

I've already seen this flow in the AAV head by adding clay to the port. So I know it's possible.

What an asset you are to this forum.

However most of what you have done is going to take a few reads to go in my head properly.

With a 30* back cut valve and smoothed ports, on a 1272 head, Is it going to be worth it?

Max

How did I not see all this before... awesome work

Cheers for posting up the info, your work does not go un-noticed

asked for this to be pinned, top information and it will be of use to some, or many!

awesome stuff mate...

been looking for some good knowledge on head porting/flowing... would it be nieve to think that when people say that port size is too big on and 1300 head that when on a G40 being under boost this may not be the case? I am building up a G engine atm and want to the get some head work done but was going to ask my engineer to improve the flow/open up the angle that the port turns down to the valve on as his suggestion was that port size was big enough already but he would just take out any ridges, rough edges and any casting marks...iirc

any advice appreciated cheers Ad

Great read, Done on the same flow bench as we have at work. I'll get my data up once I'm 'benched the head

It'll be interesting to see how they compare.

I doubt they'll be the same though, unless you use an identical bore adaptor to me.

Mine is 74mm diameter, and really long.

About 20cm long.

I wanted time for the air flow to calm down before entering the bench, but I think this wasn't such a great idea on reflection.

There is quite a bit of pressure recovery over such a long adaptor.

I tested this by tapping the adaptor and placing a water manometer at the top.

At low lift the water manometer can read upto 12" while the bench manometer reads a solid 10".

Effectively increasing the test pressure and therefore CFM.

It calms down a higher lift.

It doesn't make any difference to me as all my testing was done with the same gear. But if you start comparing number from different benches they will vary a bit due to set up.

I've to make an adaptor yet, the ones we use are all aroun 4" as its always used for big V8 heads

Nice work youve done here! Did you do any test with a valve in? I've always found the best power heads will flow slightly less without a valve fitted although being inferior on flow numbers alone.

Edited 3 February, 201115 yr by shaun_89

Standard AAV port with no valve flowed slightly less than a standard AAV port with valve.

I didn't test a modified port.