Has anyone on the board had any experience with the Kaase P-38 heads? I saw a set being worked by Ron at Fox Lake a while back and they looked somewhat impressive. I don't see a lot of internet discussion about them, however. Thoughts?
I understand that they work pretty well making good power.However,most of the high HP guys I see at the track are using either Yates,Brodix,CHI, or ported Trick Flows.All of these hds I`ve mentioned will flow over 350cfm on the intake side & at least 220 on the exhaust side.
Haven't run them yet.. but awesome heads. As you may remember from my "what headers fit high-port exhaust ports" thread a while back.. I have a set on the back burner as I finish a couple of other projects right now. Mine were purchased as more of a "blank canvass" so to speak though(un-drilled I/E mounting locations). In the interim, I will use my little RHS 160's on my old and well seasoned short-block to get the job done well enough for now. My take on them is this. Aside from the full on race castings($$$$), they are absolutely THE best aftermarket head on the market next to the slightly lessor TFS 11R when it comes to the combustion chamber design. Best pocket and bowl in as-cast form on the market. Lots of extra metal(very heavy) and huge porting potential. No shaft rockers required either. No stock valve angle head can match them and people get far far too caught up on dry flow numbers.. for which these heads still do plenty well with over 300 cfm @ .500 lift. This helps maximize power under the entire curve without having to throw such huge duration and lift at them just to reach your power goals. I have no doubt that 400 cfm is possible with a raised port design like I'm shooting for. My ports will be too small to hit that peak though, so just putting that out there for you bigger CID stroker guys. Enhancing wet flow improvements and making fuller use of the valves curtain area is where it's at on the piston end of things. If it was only about raw cfm numbers?.. we'd probably have many less castings available in the SBF market and more would still be using hogged out and port-plated Cleveland heads. lol My only real complaint is that the stock location exhaust port design is a bit weaker than the raised port stuff and cannot be raised to the same extent that the others are capable of. BUT.. they still flow in excess of 250 cfm on a bench and can easily be shored up well enough with a good scavenge type header design though. I would suggest getting ahold of Cliff at Kasse's shop to get some references to others/race teams using them. A few well timed phone calls will open your eyes to their real and full potential. Rulebooks and weight penalties are generally why you don't see them being used more often in the mainstream. That.. and Kasse doesn't beleive in bribing the magazines with advertising $$$ to help spin doctor them into all their "unbiased testing". Plus, people in general are just dense and too damned brand loyal, IMHO. I buy based on designs and casting potential and these things have that in spades.
The thing I always liked about Kaase was his humble, low key style. He doesn't make wild, over the top claims about anything he builds. His stuff just flat out runs. I find it interesting that he decided to make a hybrid Windsor head when it was his Cleveland prowess that wrought havoc at the Engine Masters. If I ever decide to build my 363 street engine, it will be a tough choice between a Aussie Cleveland & a P-38 canted Windsor head. The Aussie's have really done a fantastic job with the Cleveland design when it comes to street/strip applications.
Look at what Craig Hedja`s Maverick (434 cleveland) is running w/ CHI heads in the Ozark Mountain Super Shifters,5.23 in the 1/8 mile,I think that says it all.I`m not taking anything away from John Kaase,he makes a fine product,but if you want to go really fast the other hds I`ve mentioned will do a better job as I have seen them in action.
Dan, In my mind, the only head design to use in a max performance application NA is the Cleveland design, be it a Brodix Neil, Yates, BT, SC-1, CHI etc. I think the Kaase head falls somewhere in between a Windsor and Cleveland and may be the best bet when building a dual purpose street/strip engine, if for no other reason than it allows you to close the hood with most intakes. The P-38's work with a variety of intakes and headers. When it comes to a shock towered maverick or Comet, this is important. My heart keeps saying Cleveland while my head says "Windsor". Having said that, I keep checking out "Racing Rangers" Boss Comet with envious eyes
You almost completely nailed it. Stock port locations will always cause some level of compromise vs relocating and twisting the original Cleveland architecture. Stock Clevelands are plagued with similar problems as well. Kasse originally developed these heads to also include a high-port version but backed away from the endeavor due to market saturation. But.. there is more than ample material to do it yourself and many have also used far less superior castings to be welded on anyways. This is a VERY solid design with room to grow for the bigger 420 cid+ stroker motors. The real hidden beauty of the canted design is that the higher you go?.. the wider you can make the port without even getting into pushrod relocation/offset rockers. Also keep in mind that Kasse has helped R&D many versions and iterations of the CHI heads through the years. In fact, I'd even go so far as to say that CHI wouldn't be as advanced as they are today without guys like him pushing their designs for greater improvements. The C400 is his baby. And.. I've held onto some of the CHI castings a few times and can tell you for fact that he P38's have a superior combustion chamber and can also be rolled/angle milled to greater degrees that the CHI stuff. Raising the ports, enlarging intake valve size, and moving the head a bit with offset dowels/redrilling dowel locations can easily get you to the same level as the CHI stuff. Course, doing those same mod's to the CHI stuff can still trump them.. but he has told me that 800+ horsepower is cake with worked P38's and 700+hp is the norm on milder 427 builds using un-ported castings and still somewhat conservative cam timing that can be daily driven without drive-ability issues. The bigger thing to keep in mind with these castings is that their CSA is smaller than many mid-level castings despite their larger 240cc port volume. Big valve pockets and smaller cross sections mean extra torque for the street vs the considerably larger port volume race castings being discussed in comparison. HIGHLY under-rated head design, this is.
I know some will beleive that these Windsor based heads will not hang with the big boys. But they would be wrong. This ^^^ is possible WITHOUT welding roofs or offset PR locations. Like I said above.. the design was cast with the intention of a high-port version, so the material is there. 350 cfm is available with light grinding and not too hard to imagine that I wasn't exaggerating about those 400 cfm flow numbers if you decided to get more extreme with the mod's. Damned near the same power potential at half the cost of the bigger race stuff. Also worth noting that a Cleveland Edelbrock RPM(or CHI's version) dual plane intake manifold(or single plane design if you prefer) can be lightly mod'd to bolt right on to a high-port version such as this too. Needs a valley cover and water crossover(both available aftermarket(CHI and others).. or not hard to fabricate in the scheme of things) to make it all come together.
I remember back in the early PS days, Cleveland racers would add a bunch of braze to the top of the iron 4V intake runner and angle mill them to achieve a more direct shot to the valve. This required a furnace to keep the head up to temp and a lot of patience. These castings appear to already have necessary meat in them to do both.
I wish I knew the answer to that but it was simply a quick chop'n'mock of.. "what if I wanted to make my life much easier and simply use the material available in as-cast form to enable the use of an off-shelf Cleveland.. or even an 8.7 Super Vic.. intake?". So, I ordered a Cleveland air-gap and mocked it all up. Looked awesome and would probably confuse the hell out of most people. lol Would be a killer street setup for a smaller/mid-sized cid motor but I want more than that when the time comes to bolt them onto my man-o-war aluminum block. Shooting for around 8,000 - 8,200 rpm redline.. endurance type deal. 525 - 550 horse is a conservative power estimate from this big-bore short stroke deal. However, I can tell you with near absolute certainty(I've done several other "high-ports" through the years, some Clevelands as well, and none were what anyone would call "dud's") that I sure didn't ruin the heads flow numbers which Kasse designed in and sold me on to begin with. Cross sectional area is slightly smaller that the as-cast version but the straighter shot(taller/longer/smoother SSR) should help even the score back up towards the original as-cast sizing at the very least. If you look at Kasse's P38 web page for flow numbers you can see that the Windsor architecture certainly doesn't leave them short changed very much at all. As cast form nears 300 cfm at only .500 lift and they keep on flowing past .700 lift with some conventional port work. He also has ported numbers posted there as well but that's still not a high port version like mine and there's obviously plenty more left on the table if you want to continue working for it. I'll move the head away from the chamber wall about .050 and shrink the exhaust valve to 1.54" to allow a larger 2.16" intake valve. Heavily angle milled in the .140 - .160 thou range with a final pass or two to get the chamber to around high 40 cc range after some additional chamber work is added into the equation. Final valve angles will be under 7° intake.. and under 9° on the exhaust. Well over 12:1 compression and E-85 will still allow us plenty of street duty. The heads are on the back burner until I can get all my ducks in a row and am able to spend the time and money to do them up the way I really want. They'll be filled with aluminum on floors and roof and putty work will be very limited. Valve cover spacers are partially done and will be welded/milled onto the head to push the intake ports entry to the maximum possible height. Custom intake manifold will obviously be needed at that point but port plate/spacers would easily allow an off-shelf manifold to be used as well.. could probably also use a milled down or re-flanged 9.5 deck intake if I really wanted to. The exhaust side will just be lifted as high as the water passages will allow with some margin left in, widened out a fair bit, and floor filled/stuffed with aluminum as well. Will also weld port plate extensions onto each individual port and use a 3" bolt spread header flange.. with custom stainless headers of course. Sort of a raised squashed port exhaust type deal when it's all said and done. Maybe a bit over 250 cfm with the pipe if I get it closer to right.
Yeah,if you have ever looked at the Nascar heads,they have smaller valves than you think they would & strange looking combustion chambers.I looked at a set closely 2 years ago that Jim Stugart had at Va Motorsports Park in Petersburg Va.He worked down there for a while & has connections & buys their used heads & rebuilds them.A number of racers in the Pro Stick class are using them on n/a 377ci mtrs,11/1 comp ratio turning about 7400 rpm.They were racing a 1000 ft at Maryland Intl Raceway 2 yrs ago,many were putting down 7.40 times,pretty stout.They are the way to go if you can afford them,out of my range,$7500 bare,no valves,no guides & lots of machine work to get them ready to go.However,they say on the flow bench they can flow as high as 470 on the intake side & I don`t know of anything else that can match them,that is why a 358ci mtr in Nascar can make over 800HP.
Dan, Have you ever looked at the C3 and D3 heads that Roush/Yates sells? I've seen used heads that come off of the ARCA and Cup motors they build that go for $3,500-$4,500 a set.
Nascar is far too homogenized and rule limited and will never truly show you what the true potential of cylinder heads are when the veil is lifted. If you guys want to see and study some REALLY badass max effort heads?.. google "Frankenstein heads".. or "CFE heads". These guys make heads that flow WELL over 500 cfm and even have many versions with small 1.58" exhaust valves flowing over 300 cfm. No rules.. no restrictions.. and no budget limitations has that affect on a heads final design.
