Here are the dyno results where three different header designs were tested on a +060 over 292 Y that has stock (unported) 1957 ECZ-G heads, 1957 ECZ-B 4V intake, an Isky 228°/238° @ 0.050” camshaft  with 110° lobe centers, 1.43:1 rockers, and a Ford 1.08” (440 cfm) 4V carburetor.  Engine performance comparisons are made in the 2500-5500 rpm range.  The EMC headers are a 1.75”/1.875” stepped header with mufflers.  The Reds headers have 1½” diameter tubes and are the pickup/truck headers (intermediate length tubes).  The Tri-Y headers are firing order specific for the Y and have 1.625” primary tubes.  Only the EMC headers were run with mufflers in place; just didn’t have mufflers for the other sized pipes.

 

 

Scoring is calculated by adding the average torque and horsepower values for the 2500 to 6500 rpm pulls, multiplying by 1000 and dividing by the cubic inch of the engine.  The scores are as follows:

EMC headers  1628pts

Reds headers   1623pts

Tri-Y headers  1607pts

 

I’ll add that the flattened out torque curve exhibited by the Tri-Y headers is similar to what has been seen with Tri-Y headers on other engines that used them.

Lorena, Texas (South of Waco)

So it looks like tri Y headers are mostly hype. I've always heard that they are better for low end. The 1 1/2" header is the clear winner for the street. Were they car or truck headers?


Lawrenceville, GA

Charlie, I think Ted said Red's Headers were long tube truck headers. I'm very impressed by the performance of the Red's headers. Big improvement in torque at low engine speeds, and tracks the EMC headers through the mid-range.



Like the other graph of the 60 over 272, there's a small wiggle in the 4000 rpm range, except for the EMC headers. Bigger engine, larger valves and a cam with a closer centerline might be the reason it's happening sooner. I'm still thinking the wiggle is caused by intake or exhaust tuning effects. I'll guess that adding an air cleaner helps smooth that wiggle.



Comparing the torque per cubic inch, this tune does better than the 272's tune at first glance.

Best regards,



Paul Menten

Meridian, Idaho

Ted, again, thank you so much for taking time to test these exhaust systems. They are very informative. Keep 'em coming! Ryan

Heber City, UT (15 mins outside of Park City- basically it's in the mountains)

55 Effie

I noticed that the graph starts at 2500rpm. Does the dyno work at lower RPM? I've only heard that tri-Ys are excellent for the street. Looking at the graph, it doesn't seem to be the case but perhaps it is stronger than the others below 2500rpm and we just aren't able to see it.


Lawrenceville, GA

Hey Ted, Where did you get my engine? I thought it was in my car in the garage, I guess I better go check.

Nearly Identical to what I am running except for the cam I have the Clay Smith C-272-8-B which I believe is on the same 110 centerline, Just a minute, let me go get the card. Hmmm don't say the lobe centerline but it is a 224* @ 50 duration .446" lift on both intake and exhaust.

I decked to .010 in the hole with .030 off the heads. Best gasket, and the rollmaster advanced 4*. How much in the hole are you on this engine and has any been taken off the heads and is it using a best gasket? Cam strait up or what?

Just curious because this is a real close setup to mine.

55 Vicky & customline

58 Rack Dump, 55 F350 yard truck, 57 F100

59 & 61 P 400's, 58 F100 custom cab, 69 F100, 79 F150, 82 F600 ramp truck, 90 mustang conv 7 up, 94 Mustang, Should I continue?

The cam in the 301 that was dyno tested is installed 4° advanced.  Best Gaskets were used.  Heads only had enough taken off of them to clean them up.  Some of the other details escape my mind right now but the engine was essentially a stocker with a pump gas friendly compression ratio.

Lorena, Texas (South of Waco)

The dyno can be programmed to go as low as 100 rpms to start test pulls but the camming, carburetion, and compression ratio on an engine typically dictates where to start the dyno pulls.  With the 228/238° camshaft, the dyno pulls were started on the 301Y at 2500 rpms simply to keep from loading the engine too heavily at the start of the pull.  The lower the rpm start point, the harder it is on the main bearings from a loading standpoint.  Same is true for this same engine in a car as you really don’t want to begin a full throttle acceleration run in high gear starting at  a point lower than 2500 rpms.

Lorena, Texas (South of Waco)

Thanks Ted,

I figured I was in that ballpark, the only other differnce is I am using the 1.54 ratio rockers.

55 Vicky & customline

58 Rack Dump, 55 F350 yard truck, 57 F100

59 & 61 P 400's, 58 F100 custom cab, 69 F100, 79 F150, 82 F600 ramp truck, 90 mustang conv 7 up, 94 Mustang, Should I continue?

hey ted, did you check the ecm headers without the mufflers, did the numbers drop?

 lincoln/merc. y-blocks &mel's                                                               bucyrus, ohio.