[RallyBob]

Go ahead Bob!
I'm back from holidays so I have some time now.
Post your data & comments here on this forum,
I will make/post the plots & update your webpage @ RROC.
Cheers,
Hiro

I found some more flow charts for various head types. Now you have work right up until winter...

1.9 competition-ported, 1.85" intake valves, 1.50" exhaust valves

Intake port:..... Exhaust port:
.100" - 37.5 cfm..... 31 cfm
.150" - 53 cfm..... 46 cfm
.200" - 71 cfm..... 54 cfm
.250" - 86.5 cfm..... 68 cfm
.300" - 99 cfm..... 76 cfm
.350" - 110.5 cfm..... 86.5 cfm
.400" - 120 cfm..... 96 cfm
.425" - 122 cfm..... 100 cfm
.450" - 124.5 cfm..... 103 cfm
.475" - 126 cfm..... 105 cfm
.500" - 126 cfm..... 106 cfm
.525" - 126 cfm..... 106.5 cfm
.550" - 128.5 cfm..... 107.5 cfm
.575" - 128.5 cfm..... 108 cfm
.600" - 128.5 cfm..... 108 cfm

 

[RallyBob]

Here was a 1.6 litre head I built for a friend.

5/16" stems, 1.80" intake valves, 1.55" exhaust valves
Bowls blended, valves guides trimmed only.

Intake port:.... Exhaust port:
.100" - 31 cfm.... 31 cfm
.150" - 42 cfm... 42 cfm
.200" - 53 cfm... 51.5 cfm
.250" - 67 cfm... 61 cfm
.300" - 78 cfm... 66 cfm
.350" - 88 cfm... 71 cfm
.400" - 95.5 cfm... 75 cfm
.425" - 99 cfm... 78 cfm
.450" - 100 cfm... 79.5 cfm
.500" - 102 cfm... 81 cfm
.525" - 102 cfm... 82 cfm
.550" - 102.5 cfm... 83 cfm
.575" - 103.5 cfm... 83.5 cfm
.600" - 104 cfm... 83.5 cfm

Same head, but with competition porting done.

Intake port:... Exhaust port:
.100" - 35.5 cfm... 32 cfm
.150" - 52 cfm... 43.5 cfm
.200" - 65 cfm... 53 cfm
.250" - 78 cfm... 62 cfm
.300" - 90.5 cfm... 72.5 cfm
.350" - 103.5 cfm... 81 cfm
.400" - 109 cfm... 90.5 cfm
.425" - 115 cfm... 93 cfm
.450" - 119 cfm... 95 cfm
.475" - 121 cfm... 96 cfm
.500" - 124 cfm...97.5 cfm
.525" - 125 cfm... 100 cfm
.550" - 125.5 cfm... 101.5 cfm

 

[RallyBob]

Here is a stock 2.2 head head flow.

Intake port:... Exhaust port:
.100" - 42 cfm... 33 cfm
.150" - 57 cfm... 45 cfm
.200" - 75 cfm... 56 cfm
.250" - 89 cfm... 65 cfm
.300" - 102 cfm... 72 cfm
.350" - 109 cfm... 75 cfm
.400" - 113 cfm... 75 cfm
.425" - 115 cfm... 75 cfm
.450" - 118 cfm... 75 cfm
.475" - 119 cfm... 77 cfm
.500" - 119 cfm... 77 cfm
.525" - 120 cfm... 77 cfm
.550" - 120 cfm... 77 cfm

Now here is a high performance street 2.2 with 1.94" intake valves and 1.60" exhaust valves.
Intake port:... Exhaust port:
.100" - 40 cfm... 31 cfm
.150" - 57 cfm... 43.5 cfm
.200" - 74 cfm... 53 cfm
.250" - 89 cfm... 65.5 cfm
.300" - 101 cfm... 76.5 cfm
.350" - 115.5 cfm... 86 cfm
.400" - 128 cfm... 95 cfm
.425" - 134 cfm... 99 cfm
.450" - 139 cfm... 101 cfm
.475" - 143.5 cfm... 102 cfm
.500" - 146 cfm... 102 cfm
.525" - 146 cfm... 102 cfm
.550" - 146 cfm... 103.5 cfm
.575" - 146 cfm... 103.5 cfm
.600" - 146 cfm... 105 cfm

 

[RallyBob]

Stock 2.4 litre head.

Intake port:... Exhaust port:
.100" - 36 cfm... 28 cfm
.150" - 50 cfm... 42 cfm
.200" - 68 cfm... 54.5 cfm
.250" - 84 cfm... 68.5 cfm
.300" - 99 cfm... 78 cfm
.350" - 110.5 cfm... 86 cfm
.400" - 109 cfm... 89 cfm
.425" - 110 cfm... 91 cfm
.450" - 110.5 cfm... 93 cfm
.475" - 110.5 cfm... 94 cfm

High performance street ported 2.4 head with 1.94"/1.60" valves.

.100" - 36 cfm... 31 cfm
.150" - 53 cfm... 46 cfm
.200" - 68.5 cfm... 58.5 cfm
.250" - 84 cfm... 72.5 cfm
.300" - 100 cfm... 83.5 cfm
.350" - 112.5 cfm... 90.5 cfm
.400" - 126.5 cfm... 100 cfm
.425" - 132 cfm... 103.5 cfm
.450" - 136 cfm... 106.5 cfm
.475" - 138 cfm... 108 cfm
.500" - 139 cfm... 110 cfm
.525" - 140 cfm... 112 cfm
.550" - 141 cfm... 113 cfm
.575" - 143 cfm... 115 cfm
.600" - 144 cfm... 115.5 cfm

You'll note that when modified, both the 2.2 heads and 2.4 heads both don't really start 'coming alive' until about .400" valve lift. What that means is if you are running a typical .430" lift street cam you're not letting the head make any power! A prepped 1.9 head is a better choice with low valve lift.

 

[Hiro]

I found some more flow charts for various head types. Now you have work right up until winter...

1.9 competition-ported, 1.85" intake valves, 1.50" exhaust valves

Intake port:..... Exhaust port:
.100" - 37.5 cfm..... 31 cfm
.150" - 53 cfm..... 46 cfm
.200" - 71 cfm..... 54 cfm
.250" - 86.5 cfm..... 68 cfm
.300" - 99 cfm..... 76 cfm
.350" - 110.5 cfm..... 86.5 cfm
.400" - 120 cfm..... 96 cfm
.425" - 122 cfm..... 100 cfm
.450" - 124.5 cfm..... 103 cfm
.475" - 126 cfm..... 105 cfm
.500" - 126 cfm..... 106 cfm
.525" - 126 cfm..... 106.5 cfm
.550" - 128.5 cfm..... 107.5 cfm
.575" - 128.5 cfm..... 108 cfm
.600" - 128.5 cfm..... 108 cfm

thanks for the data Bob!
I'll work on it back home this evening,
back to work today with lots of paperwork sh... to deal with!
Hiro

 

[RallyBob]

Okay, more data gathering occurred today!

I ported a street 2.4 head last week, and wanted to flow-test the bare head, as well as the Dbilas DSD intake manifolds which were port-matched to the head. Then it occured to me I had never flow-tested the cut-down 3.0 litre EFI intake I had prepared for another engine with a 2.4 head, so here was my chance to compare a ported big-valve 2.4 head (bare port), the DSD intakes, and the EFI intake on the same day, minimizing the variables.

So, here are the results on the intake port with a 1.94" valve:

Bare port........Dbilas intake.....EFI intake

.100" - 33.5 cfm... 32 cfm... 32 cfm
.150" - 50 cfm... 47.5 cfm... 46 cfm
.200" - 68.5 cfm...65.5 cfm... 63.5 cfm
.250" - 88 cfm... 83.5 cfm... 80 cfm
.300" - 106.5 cfm... 100 cfm... 93.5 cfm
.350" - 123 cfm... 115.5 cfm... 105 cfm
.400" - 132 cfm... 124 cfm... 113 cfm
.425" - 137 cfm... 128.5 cfm... 116.5 cfm
.450" - 137 cfm... 131.5 cfm... 119 cfm
.475" - 137 cfm... 134 cfm... 121.5 cfm
.500" - 137 cfm... 134 cfm... 123 cfm
.525" - 138 cfm... 134 cfm... 121.5 cfm
.550" - 138 cfm... 134 cfm... 120 cfm

Years ago I tested a ported 2.2 head, and it flowed a peak of 136 cfm through the bare intake port. I then bolted a stock 2.2 EFI intake manifold to that head, and the flow peaked at 99 cfm! I had another 2.2 intake on loan from Gil (OGTS) that had been Extrude-Honed, and it peaked at 100.5 cfm....only 1.5 cfm more! So you can see how bad the 2.2 intakes truly are...

And for posterity, the cylinder #1 exhaust port with a 1.60" valve:
.100" - 32 cfm
.150" - 47.5 cfm
.200" - 60 cfm
.250" - 71 cfm
.300" - 81 cm
.350" - 88.5 cfm
.400" - 94 cfm
.425" - 96 cfm
.450" - 97.5 cfm
.475" - 98 cfm
.500" - 99 cfm
.525" - 100 cfm
.550" - 100.5 cfm

 

[Hiro]

Okay, more data gathering occurred today!

I ported a street 2.4 head last week, and wanted to flow-test the bare head, as well as the Dbilas DSD intake manifolds which were port-matched to the head. Then it occured to me I had never flow-tested the cut-down 3.0 litre EFI intake I had prepared for another engine with a 2.4 head, so here was my chance to compare a ported big-valve 2.4 head (bare port), the DSD intakes, and the EFI intake on the same day, minimizing the variables.

So, here are the results on the intake port with a 1.94" valve:

Bare port........Dbilas intake.....EFI intake

.100" - 33.5 cfm... 32 cfm... 32 cfm
.150" - 50 cfm... 47.5 cfm... 46 cfm
.200" - 68.5 cfm...65.5 cfm... 63.5 cfm
.250" - 88 cfm... 83.5 cfm... 80 cfm
.300" - 106.5 cfm... 100 cfm... 93.5 cfm
.350" - 123 cfm... 115.5 cfm... 105 cfm
.400" - 132 cfm... 124 cfm... 113 cfm
.425" - 137 cfm... 128.5 cfm... 116.5 cfm
.450" - 137 cfm... 131.5 cfm... 119 cfm
.475" - 137 cfm... 134 cfm... 121.5 cfm
.500" - 137 cfm... 134 cfm... 123 cfm
.525" - 138 cfm... 134 cfm... 121.5 cfm
.550" - 138 cfm... 134 cfm... 120 cfm

Years ago I tested a ported 2.2 head, and it flowed a peak of 136 cfm through the bare intake port. I then bolted a stock 2.2 EFI intake manifold to that head, and the flow peaked at 99 cfm! I had another 2.2 intake on loan from Gil (OGTS) that had been Extrude-Honed, and it peaked at 100.5 cfm....only 1.5 cfm more! So you can see how bad the 2.2 intakes truly are...

And for posterity, the cylinder #1 exhaust port with a 1.60" valve:
.100" - 32 cfm
.150" - 47.5 cfm
.200" - 60 cfm
.250" - 71 cfm
.300" - 81 cm
.350" - 88.5 cfm
.400" - 94 cfm
.425" - 96 cfm
.450" - 97.5 cfm
.475" - 98 cfm
.500" - 99 cfm
.525" - 100 cfm
.550" - 100.5 cfm

very interesting data Bob!
I will make the plots tomorrow.
Hiro

 

[neuropel]

So what's the source of restriction on the top side for the 3.0L EFI? It actually starts going the wrong way...

Todd

 

[Hiro]

thanks for the data Bob!
I'll work on it back home this evening,
back to work today with lots of paperwork sh... to deal with!
Hiro

OK some plots using Bob's flow data,
first here are the merged plots for all intake & exhaust respectively:

 

[Hiro]

the two previous plots are quite messy,
so now let's go head by head separately,
here are the "low intake cast" port heads:

 

[Hiro]

and here are the "tall intake cast" heads:

 

[Hiro]

now comparing the two 1.6 heads both intake & exhaust on the same plot,
or the three 1.9 heads intake or exhaust separately:

 

[Hiro]

all 2.2 head data on the same plot,
all 2.4 head data on the same plot:

 

[Hiro]

now just to emphazise the fact that the 2.2 & 2.4 heads are flowing very differently,
in spite of their similar external shape,
I compared all 2.2/2.4 data from intake or exhaust on two different plots:

 

[Hiro]

Bob if you need other types of plots,
or dual/multiple compare that I did not plot yet,
just ask!
Hiro

 

[RallyBob]

So what's the source of restriction on the top side for the 3.0L EFI? It actually starts going the wrong way...

Todd

Who *really* knows Todd...most engines eventually 'stall' their airflow at some point. I think the bends in the manifold runners create enough surface friction to reduce the peak airflow. Not an issue with a manifold with a 'straight shot' to the valves like DSD intakes.

I suspect that running a custom plenum-type intake with straight runners that are parallel to each other would be even better.

Bob

 

[RallyBob]

Bob if you need other types of plots,
or dual/multiple compare that I did not plot yet,
just ask!
Hiro

Wow! Very nice work Hiro! And very fast too....:notworthy

How about this latest comparison with the bare 2.4 port/Dbilas/3.0 inlet manifold?

Bob

 

[samdog]

I know the perfect motor that would be a ready and willing doner for that cut down 3.0 efi !!!!!! Hey, Dr Bob...you make the call and the patient will be there. Thanks

 

[wrench459 (R.I.P.)]

Not an issue with a manifold with a 'straight shot' to the valves like DSD intakes.

I suspect that running a custom plenum-type intake with straight runners that are parallel to each other would be even better.

Bob

I'm liking where your going with this!
How about a custom intake with no plenum ..phased injectors using a EEC-IV
V-8 ecm? Say goodbye to the heater core on a GT. Will need a special algorithm forgive me just thinking...

 

[wrench459 (R.I.P.)]

Using the EEC-IV ecm
Lower Fo1=Op1,Fo7=Op3,Fo6=Op4,Fo4=Op2
Upper Fo3=1,Fo2=3,Fo5=4,Fo8=2
Daughterboard to handle the offset on the upper injectors?
Or twin four cylinder ecms