Small intake port head with a " better" combustion chamber and 2.02 intakes?

[Mr Woodys Garage]

Graph, Showing No RPM Or HP "Fall Off" Above 6200 RPM.  There Is More Potential To Be Had, This Is Just Where I Ran Out Of Time And Money. The Smaller Numbers/Graph Was The Same Engine, Before Teardown And Having Lifter Bore Correction And Roller Cam Bearings Installed, Which Woke It Up A Bit More Than The Already Respectable Numbers. My Only Regret With The Build, And These Heads Was That I Used The Premium (Full Roler) Harlan Sharp Rocker System With Them (Changed The Adjusters To Use Ball/Ball Pushrods, And Oil Through Them) I Didnt Want To Cut The Heads Up For The Much Better T&D Rocker System., Which Was The Only Choice For An Upgrade At The Time Of The Build. Within A Month Of My Engine Being Finished, And Dyno'd, They Came Out With The TFS Specific Rocker System For These Heads. Certainly Would Have Rather Used Them. Demand Is Definately There For Hi-Fi FE Parts. Still A Lot To Be Said For The Iron Heads, But For The Money, The TFS Heads Can't Be Beat.

[blykins]

I also have some corresponding dyno data. 465" Engine with the EMC heads, and also out-of-the-box TFS heads.

Only disappointing part of the TFS heads is they hit a wall around 6200-6300


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I'm wondering what you had going on there.  Maybe it was an issue with that particular pair of heads? 

Here's a 449 that I did with out of the box TFS heads:



Here's a 465 that I did with out of the box TFS heads:



Neither had a problem with rpm, so I'm wondering maybe if your heads had a port/valve job issue???

I do know that when I do a hydraulic roller with these, the setup has to be *light* in order to get them to pull on up.

Regardless, as you have shown, the amount of off-the-shelf performance that you get for $2600 is awesome. 

[e philpott]

CaptainCobraJet and Mike Brunsons flow benches seem to be similar, CCJ quote on the TFS's were 310 at .500 and Mike's flowbench is 308 at .500

[CaptCobrajet]

I'd say Mike's data is pretty accurate.  The power curves correspond pretty well to the flow he witnessed.  The iron EMC heads I sell have nice  11/32 stem valves.  The contest heads did have a rather expensive set of 5/16 stem valves with some back angles that I don't sell, just in case I ever go racing again, lol.   The valves size is 2.150 in the iron.  Bigger than that gets pretty thin around the spark plug hole.  It would respond to a 2.200 valve, but it wouldn't live long before it would leak beside the plug hole.

That back-up in the TFS head is a real thing.  I have noticed over 20 years of flowing on my bench, that it is more finicky about turbulence than a Superflow.  Mine seems to expose the turbulence and it affects the flow more than the Superflow benches.   I am not smart enough to know why, but I know it happens.  The crutch for the turbulence is most likely wider lobe separation, but it will take torque away through most of the curve, as it helps it hang on up top.

Mike's more than likely had a tighter lobe sep than Brent's examples, and the torque was there bigger and sooner, and then it ran out of breath.  Overlap will aggravate the sonic problem in the TFS head.  If the exhaust isn't pulling it through as hard, the turbulence is less pronounced.  The downside is the loss of usable torque by going wider.  Torque is king unless you plan to drive one around at 6000 rpm, so chasing a peak power number that loses you torque at lower revs isn't how I would do it.   This has turned into an interesting thread.  It brings to light the fact that different heads have different personalities, beyond just flow numbers, and they all won't like the same cams.

[66gtafairlane]

I also have some corresponding dyno data. 465" Engine with the EMC heads, and also out-of-the-box TFS heads.

Only disappointing part of the TFS heads is they hit a wall around 6200-6300


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Mike, are willing to give some engine specs ie.compression, intake, headers ?

[66gtafairlane]

I also have some corresponding dyno data. 465" Engine with the EMC heads, and also out-of-the-box TFS heads.

Only disappointing part of the TFS heads is they hit a wall around 6200-6300


picture hosting

Nice ! Mike can you give more information, ie compression, cam intake etc.

[66gtafairlane]

I also have some corresponding dyno data. 465" Engine with the EMC heads, and also out-of-the-box TFS heads.

Only disappointing part of the TFS heads is they hit a wall around 6200-6300


picture hosting

I'm wondering what you had going on there.  Maybe it was an issue with that particular pair of heads? 

Here's a 449 that I did with out of the box TFS heads:



Here's a 465 that I did with out of the box TFS heads:



Neither had a problem with rpm, so I'm wondering maybe if your heads had a port/valve job issue???

I do know that when I do a hydraulic roller with these, the setup has to be *light* in order to get them to pull on up.

Regardless, as you have shown, the amount of off-the-shelf performance that you get for $2600 is awesome.

Truly amazing figures for FE / strokers, both OEM iron and aftermarket aluminum. Have been used to seen these kind of hp/figures/ci for those 351 W / 460 strokers which I have been building for some 30 years -makes me really happy and looking forward to my new 462 build for my 66 GTA.

[blykins]

I don't want to lump anything all together in a general statement but different heads most likely will always require different cam specs.  In Mike's dyno results, it could be that the cam favored the TFS heads, or it could be that the cam favored the C4 heads.  That's something you don't know unless you do a ton of camshaft testing in situations like that, then you can almost get into a perpetual rabbit hole of variable chasing which will wear you out pretty quickly.

The amount of overlap brings up a good point.  Tighter lobe separations may help the bottom in certain combinations, but the LSA is not the only thing that controls the amount of overlap.  The advertised duration has as much say in the overlap as the LSA does.  I can have two cams:  278/278 @ seat, 240/240 @ .050", 110 LSA and 270/270 @ seat, 240/240 @ .050", 106 LSA and they will both have the exact same amount of overlap.  Will those cams behave the same?  No, and it's not because of the LSA number, it's because of the more/less aggressive lobe of each camshaft. 

[My427stang]

Mike, what were the open and closed spring pressures, same on each head?

[CaptCobrajet]

Yes, you can certainly change overlap by using more or less aggressive lobes.  That doesn’t exactly do the same thing as changing separation if using the same lobes.  That’s why there is an infinite number of combinations and lots of cam companies.  A lazy lobe will make a more linear change in area under a curve, whereas changing the position of lobes on the cam just moves where the curves happen.  The engine will digest those changes in a different way.  Lots of things to consider………

[CaptCobrajet]

All of these examples posted are all different combos.  Just looking at where peak torque happens on each one, you can conclude that Mike has the smallest cam, and Mr Woody has the biggest one. Curious how many of these engines had a dual plane manifold……..that also can affect it.  If the cam isn’t big, and the engine is, it will run out of plenum past peak and taper off.  The strength of the dual plane is it will have nicer power where you want to drive a street car.  Happy and peppy below peak torque. 

[Barry_R]

I recently had a 482" with the TFS heads on dyno.  It acted like Mike's - ran out of breath earlier than I expected, but made good power up to that point.
Since it was my first go around with TFS stuff (I am out of castings) I was not sure "why".
I have another TFS headed engine - 465" with more cam and compression - coming up on dyno next week.
Very curious to see how it behaves.

BTW - Blair's EMC engine was a bad dude....  Iron heads have not been my thing for a long time, but he schooled a bunch of other pretty sharp folks with that deal.

[mbrunson427]

Sorry, not the fastest response. I'm living my life 50/50 between Tulsa and Denver right now so unfortunately FE's have been on the backburner.

I should have done a more thorough job explaining the dyno data that I posted above. The engine is a 465" engine built by Blair (.040" over 428 block). Originally with Blair's EMC C4AE-G factory cast iron heads that were ported in that same fashion that his engine masters engine was. My '62 Galaxie was the intended recipient of this engine, but as things go, plans changed. The engine was sitting at my place and we needed a dyno mule so we swapped the 465" engine with TFS heads and also some other pro-port heads that we had laying around. Our intent is to also swap on our MR head after its 100% complete, but this has been a long drawn out process and hasn't happened yet.

The heads had beehive springs on them. Sorry Ross I didn't catalog the spring data well enough to be able to tell you here from my computer, I'd have to get back to the shop and put them on the spring tester. I understand your sentiment, you think it was valve float? We fooled around with springs a bit to make sure that wasn't the case. I assure you it wasn't. The discussion above between Blair and Brent makes the most sense as to why the TFS heads didn't want to make it past 6200 for us.

The 465" engine has a performer rpm intake on it, mildly modified. Intake divider cut down a bit and the plenum is blended. The cast iron heads were run with the same intake as the TFS. All conditions kept the same except heads.

The engine is around 10.5:1 compression. Normal dyno headers. Nothing crazy for the bottom end. I think the only bit of trickery was in the cam. It's a shorter lift cam and shorter duration but sure seems to have steep ramps on it. Almost like a stock class racer built it. Solid roller cam.

[My427stang]

I suspected float less than bounce, and given added info of a steep lobe, thinking more maybe bounce.

That being said, just bench racing, but typically what I see from a head is flattening out, not losing it's mind like that

[Barry_R]

Ran my second engine I referenced above with out of the box TFS heads.
Although a very different combination it behaved in a similar fashion - bumped it's head right around the 600HP mark.

Thinking about JDC's comments - next time I run a set they are going to get some additional touch up work to see how they respond.