New Design Type 4 Heads

Unkl Ian · Post by **Unkl Ian** » Thu Jan 15, 2009 9:04 pm

Longer shafts shouldn't be a crisis.

Offset rockers are common on domestic race stuff.

mikeG15 · Post by **mikeG15** » Fri Jan 16, 2009 4:44 pm

I don't get the logic of this design, the inlet port curves around on itself so why not have a port that fires directly into the head across the back of valves aligned with cylinder axis . This might mean a Heron type approach but with considerably improved breathing. The Type 4 is after all not a high revver.

Post by **Piledriver** » Fri Jan 16, 2009 7:51 pm

mikeG15 wrote:I don't get the logic of this design, the inlet port curves around on itself so why not have a port that fires directly into the head across the back of valves aligned with cylinder axis . This might mean a Heron type approach but with considerably improved breathing. The Type 4 is after all not a high revver.

It's more or less the stock layout.

With 50x40 valves and ports that support them properly, it could very easily be a high revver, in fact, one would have to work hard for it not to be and be efficient... Port velocity is not just a buzzword.

The valve angle or at least inclination is more or less set due to where the cam/pushrods are... Unless you went with longer/heavier rocker arms, standing it up is not an option.

The V8 guys would kill to have that angle at the valve...

Post by **Piledriver** » Fri Jan 16, 2009 9:07 pm

There is a danger in a project like this to build the "ONE True cyinder head"... The risk is building something that does nothing well, and is expensive.

Consider, for example, the USAF F-111.
(Was originally supposed to be for the Navy/Marines as well, but they ended up buying the F14... for good reasons)

The F-111 was intended to be a multi-role fighter, and as concieved, it was.

Additional requirements kept being added by the USAF, until it was an overweight slug, essentially useless as a Navy fighter, or for ground suppport... Made a for a very fast bombing platform, and was actually an awesome piece of engineering, but in the end, it was engineered to death, and couldn't meet many of its original design goals, like reliably landing on carriers.
(It technically COULD, but so can a C130)

Just a cautionary tale, I suppose...

A relatively thick, flat rocker box floor could allow for a variety of rocker setups, including the stock one.

Paul H · Post by **Paul H** » Sat Jan 17, 2009 12:04 am

Only the flange angle has been tilted slightly to allow a smoother curve into the port.The original tract has a kink and the upright flange means you need a sharp bend in the manifold to get it vertical for carbs. The previous pic shows a massive 52mm valve and port which exaggerates everything with a smaller 44-48mm valve the intake run is very smooth.
The head will cast to the original angle and the new one can be created with a simple change in the CNC machine program.
The manifold will remain as it is so if you use them on a stock head then it will tilt outwards but it's efi so not a problem and it has to be like that the get the injectors in there-it's a packaging deal and a better shape-bends kill velocity

This is a 38 to 44 mm sweep with original flange angle shown as wedge

And just for the record a dozen or so people who expressed interest in a pair of these heads said that they will happily junk the carbs or existing TB's in favour of the new shape-taking into account the low cost and style of the TB's we have that bolt to the top of that manifold.

Here's the initial T1 v T4 port layout-I'll be pulling the t1 down more to get it further away from the rocker box and get some air space in there around the guide boss

ngobet · Post by **ngobet** » Sat Jan 17, 2009 4:07 am

Paul H wrote:I think we have a way of making the die so we can have the option of a type one port set up if we want it and also a 2nd spark plug. We have decided to put more time into the machining operations than trying to make the perfect do it all die mold. This will apply to the exhaust port which will be cast as the later design and machined to the early style which will take about 1 minute on the CNC machine

machining is cost killer, you better make choices.
Diversity means you'll have to stock different heads, which might seem cheap when you have only the casting but not when machined. In addition to costs you'll have to choose which version you produce, which puts some time restrictions. I definitely think is not the successful way to a cheap quality head.

But, if you produce a single product that matches "standards" when talking about performance and t4, you'll meet a great success. Cranks, P/C(...) are getting cheaper, we only need a head capable of producing more than 200 hp without hassle ready to bolt.

Having this in mind, you should keep t4 ex pattern (and choose one...), and make the best mold you can imagine.

Of course, you definitely have to add those sexy features like material for 6 studs and twin spark, but don't propose to machine the heads. All the peoples that think about such things are probably able either to do it themselves or to pay to have it done ba y machine shop.

And in general, there are a LOT of good remarks, I like the way you designed the intake. A good quality intake manifold will be easy to sell.

You should definitely try to make your head more rigid to allow bigger engines to be built without the sealing problem. T4 original stud pattern is not the only problem (easy to add material for 6 studs), you should try to make bolts locations (the 4 lower ones) more rigid.

If you succeed, I'll be buying a few heads.

fusername · Post by **fusername** » Sat Jan 17, 2009 5:35 am

this is a really cool project, lots of fun to follow, but now every time i check in on it, I am going to have the image of a C130 landing on a carrier in my mind...

Wally · Post by **Wally** » Sat Jan 17, 2009 7:25 am

Very nice progress Paul!
I like what your doing!

Post by **Piledriver** » Sat Jan 17, 2009 10:22 am

It sounds a bit like Paul has a very decent machine shop...

Perhaps he'll have a couple>3 "standard" heads and offer the more advanced work as value-added upgrades.

(Unless you are building a VERY large or all out drag motor, 50x40 valves and CE sized ports are worse than useless)

If the meat is already in the casting, even a "full meal deal" setup could still cost ~half what a roughly equivalent head costs now, while still turning a profit on the CNC mill work. (As well as having more meat at the sealing surface etc)

I apologize for the C130 landing on a carrier visual.

Unkl Ian · Post by **Unkl Ian** » Sat Jan 17, 2009 11:52 am

Piledriver wrote: I apologize for the C130 landing on a carrier visual.

The Space Shuttle had some of the same problems, all the add-ons
made it too heavy to meet the original criteria. I think the point was,
you are not going to make everyone happy with one design.
Figure out what is important to your target market.

Paul H · Post by **Paul H** » Sat Jan 17, 2009 12:05 pm

Yeah Ok guys I'm well aware of getting carried away with exotic stuff and besides all this talk of 50 x 40's if we produce a cylinder head it will be a very normal 42 x 37 or maybe 44 x 38 standard head with later style T4 exhaust port with extra meat here and there for bigger bores and ports later.

If Bomber Harris managed to land a Lancaster on Ark Royal then you don't have any issues with C130's -it's just hair splitting right ?

Wally · Post by **Wally** » Sat Jan 17, 2009 1:24 pm

Paul H wrote:
If Bomber Harris managed to land a Lancaster on Ark Royal then you don't have any issues with C130's -it's just hair splitting right ?

haha, the man knows his history!

I have just one concern Paul: original type 4 heads bend/warp when using larger than stock cylinder size. Well, even stock isn't always safe..
So please make them more stiff even at 103mm bores

Also cooling is VERY inportant, They need to cool just like an original head (or better).

Thats it really

Post by **doc** » Sat Jan 17, 2009 1:43 pm

Paul,

Admittedly, I am the neophyte here, but can't help but feel cost is the issue you need to keep a keen eye on. T4 participation is enormously diminished in the States by the cost. In spite of claims to the contrary, any level of research produces expenses greatly exceeding T1. Parts are harder to get from fewer sources and on many items 3-4-5 times the cost. The argument about the longevity and durabliity of T4, while compelling and probably true, just can't outweigh peolple's focus on the reality of their pocketbooks. The guys who really are into big power and performance will always find the way to spring for the better stuff. Unfortunately, this group is dwarfed by the number of guys trying to scrape up enough for the next brake job. Just a reality.

High costs keep manufacturers from having enough volume to really take advantage of any economies of scale. So, I would think that cost needs to be a major factor in your design. If you can get costs down anywhere close to decent T1 product it may turn into a homerun. Costs that are only marginally better than what's already around are going to relegate you to the same small user base. Sharpen that pencil!!

My 2 cents.

doc

Wally · Post by **Wally** » Sat Jan 17, 2009 2:23 pm

doc wrote:Paul,

Admittedly, I am the neophyte here, but can't help but feel cost is the issue you need to keep a keen eye on. T4 participation is enormously diminished in the States by the cost. In spite of claims to the contrary, any level of research produces expenses greatly exceeding T1. Parts are harder to get from fewer sources and on many items 3-4-5 times the cost. The argument about the longevity and durabliity of T4, while compelling and probably true, just can't outweigh peolple's focus on the reality of their pocketbooks. The guys who really are into big power and performance will always find the way to spring for the better stuff. Unfortunately, this group is dwarfed by the number of guys trying to scrape up enough for the next brake job. Just a reality.

High costs keep manufacturers from having enough volume to really take advantage of any economies of scale. So, I would think that cost needs to be a major factor in your design. If you can get costs down anywhere close to decent T1 product it may turn into a homerun. Costs that are only marginally better than what's already around are going to relegate you to the same small user base. Sharpen that pencil!!

My 2 cents.

doc

Yeah, costs are very important too as I can't just 'spring' for engine plus heads either...

Paul H · Post by **Paul H** » Sun Jan 18, 2009 4:42 am

I know all about the VW market, how it works and what parts are in demand just need to compare the amount of Engle 110's sold compared to Engle FK89's or the amount of 69mm cranks v 82mm cranks etc.Rough calculations say we have to produce 50 pairs of heads @ $1000 a pair which is not an impossible target.We will be making the new injection system first which will be a good indicator as to who wants what.As with most things some parts will always be more popular than others and if we only catered for the fast moving stuff then everyone would be driving a 1776cc engle 110 type 1 motor