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So I am looking at selling my coupe and all its goods and get my heads done and custom cams to replace my Crower Stage III and Jan 05 heads. I just always figured I would buy a used set and send to Fox Lake. Well in April Ron retired so that is out. Who is the go to now a days for head work and aftermarket true custom cams. Not off the shelf cams with custom in the name. Is Todd still good?
Also looking at all the different shops they have 100 different options. What are musts for street car heads with huge boost that will probably max out at 7-8K. 99% sure I will do GT500 heads for my entertainment purposes.

Been working on my Masters and just been out of the loop.
 

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Josh,

The Fox Lake heads were very impressive and very effective but sadly as you pointed out, Ron has elected to retire. Here is a table I put together some time ago comparing air flow from several porting shops on both Cobra "C" heads, GT500 style heads and yes Coyote heads.

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This is the same data presented graphically.

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The line that floats above all others (including the race ported Coyote) is the Livernois Stage 3 porting job on a "C" head with 1mm oversize intake and exhaust valves. Today Livernois will attempt to talk you into a ½ mm oversize valve so they do not have to replace seats and guides. The ½mm fix looks a little better than stock but no where near as impressive as the 1 mm oversize alternative.

Livernois also has a Stage 3 GT500 head offering. It will outflow the "C" head by 15% at the bottom of the lift curve and by 9 to 10% at peak lift, this is huge. Interestingly all heads (except the Livernois Stage 3 GT500 head) converge on 330 CFM at 0.500" lift. The Livernois Stage 3 ported GT500 head with 1mm oversize valves and seats is the one exception to this. It runs at essentially 350 cfm at 0.500 lift.

I have a chart of the GT500 head performance somewhere. I need to remember where and I will post up a pic of the performance.

The most important places in a head flow curves are always the 0.100 to 0.400 lift, flow numbers. The reason for this is both the low speed cylinder filling capability and the fact that an intake or an exhaust valve will spend twice as much time at any lift point below max lift because it is there twice as long, once on the opening side of the cam and once on the closing side of the cam. It is only at peak lift once.

If for no other reason than I believe I remember you have a intake manifold modified for GT500 heads, I would look at the GT500 alternative. If the manifold were a standard "C" head manifold there is no doubt in my mind I would use the Livernois Stage 3 ported "C" heads.

I'll look for the GT500 head data this evening.


Ed

p.s. Before you spend money on cams call me. If you've lost the number PM me and I'll send it to you.
 

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My heads are done by Jason Anderson of Janderson Heads, located in MN. All the info, flow numbers etc are in the post link below, 1600whp. If I didn't have Janderson 10 minutes from me, I'd send to Modular Head Shop. For cams, Todd Warren is the man. My cams idle and drive great and make huge power.

You're looking at new valves, at minimum exhaust valve seats, valve guides, resurface, and valve job along with new valve springs. I have used Manley valves for years, been 100% reliable under big boost and power. When you do the valve seats, you might as well do the oversize valves also since you're buying valves.
 

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OK guys, here's the data on the Livernois Stage 3 GT500 heads compared to the other alternatives. I had to dig it out of a digital dust pile in the back of my hard drive. I have also included the Anderson ported heads flow data for the heads that Tony uses so you can get a sense of flow and power potential. Tony's car puts down a impressively high 1600 RWHP which is huge no matter how you slice that cake.

First I'll put up the actual flow numbers and then I'll put up the graphic comparing the different head's flow performances. Here are the numbers;

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and here is the graphical rendering of those flow figures;

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The top line that is above everyone else will bring warmth to the cockles of Josh's heart because his engine is already set up for those castings.

I included a wildcat in this data. It is the solid blue line. That line is a Roush-Yates NASCAR D3 pure race head. When you are around something continuously you begin to take it for granted. Notice that all the 4V test samples out performed the NASCAR head up through about 0.350 lift. The Livernois Stage 3, GT500 crushed everybody including the NASCAR head up to 0.500 lift! Stunning falls short of the mark when you compare the Livernois Stage 3 ported GT500 flow performance to anything else.

We have a tendency to look at peak port flow to see who presumably is the best. While peak flow is not insignificant the most important numbers are the low and mid lift numbers. The big number at the top is not insignificant but the low and mid lift numbers are absolutely essential especially. The reason is that the valve is at any lift point below max lift twice! Once on the way up to open and once on the way down to close the port. It is only at maxlift once!

All flow figures above are the reported flow figures from the respective shops at a pressure drop of 28 inches of water.

You can identify the various porting shops by the graphical trace color and the legend at the bottom of the graph. The line that rises above all others is the Stage 3 porting job on the GT500 head that is provided by Livernois. At a 0.500" lift It will outperform the flow figures that all other heads achieve (including Coyotes) at 0.600 lift. In second place is the Stage 3 Livernois "C" head using the head casting that Cobra's came with.

It is interesting to note that the Livernois ported GT500 head significantly outperforms the very good Slawko and JPC/RGR race portedCoyote heads. Even more interesting GT500 heads from other shops also perform right at or a whisker better than race ported Coyote heads.

Ford did an engineering slight of hand with the Coyote engine. In n/a form Modmotors have poor low speed torque. By increasing displacement from 4.6L to 5 liters and using dual variable cam timing Ford was able to bring back low speed torque for a good seat of the pants feel off the show room floor.

As we all know the supercharged Cobra had no problem with low speed torque other than having to much to hook up most street tires. The Coyote was an engineering slight of hand performed for the Marketing boys so they would have a horn to toot as Ford spent their new engine platform monies developing the EV vehicle program. To kill off any possibly competition from modified supercharged 4.6L sibling competitors Ford strong armed the aftermarket to stop producing 4.6L performance parts.

Things like Cloyes adjustable timing kits and 9-way adjustable secondary sprockets suddenly disappeared as inventories ran out and no replacements were manufactured. Slowly every aftermarket performance part was disappearing from both the aftermarket and importantly also the Ford performance parts we once bought at enthusiast price points. Suddenly they were no more, but you could still buy hipo 289 and 427 FE parts that were 60 years old!

Bottom line if you want to build a killer engine get the Livernois Stage 3 head either in GT500 trim or "C" head trim with the level 3 porting job. If the price is too steep you have literally the best performing heads available for the 4.6 in the tables and graphs above. Pick what your budget will allow an go for it.


Ed
 

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Ed, just a minor correction on your chart. My Janderson ported heads are DB '03 castings, not gt500. Also, it is very hard to compare flow numbers unless they are all flowed on the same bench. While they are all supposed to be calibrated to provide similar results, there is likely a several percentage point difference. Other than that, great info
 

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Thanks for the sharp eyes, Tony. I've updated the post to reflect your correction to my mis-statement. Your observations about flow bench calibration are spot on. Ideally you want to believe the various shops do a credible job of calibrating. I believe most try to however, I have no doubt that the press of daily business can cause a few corners to be cut from time to time. Hopefully the differences are small enough to be down in the noise level.


Ed
 
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