I personally am looking for a source for a camshaft ground to specs similar to the Ford racing parts M-6250-A332 except ground on 112 lobe centers and 214(in) and 220(ex) durations and close to .500 lift. I have yet to work out piston configuration, still working out stroke options. Nelson cams may be a possible source of cams, they ground a 214/214 cam with approximately .5 inch lift for Royce Brechler.

All of this can be done by individuals but are Ted and John going to introduce some of these items to hit the market in conjunction with the new heads?

The new high lift, agressive ramp cams are on the market for a reason. 1950's cam technology leaves a LOT on the table. 

DW

Don, i am curious what is your car application with these changes you mention, i wouldnt think as dailey driver, i would be guessing once a month go tear up some rubber somewhere? or just great looking and sounding engine? I think milder specs for daily nicer to drive car. regards bill.

Cam will be 214in 220ex @.050, 112 lobe centers, at least .500 lift with 1.6 rockers, 10.2 CR. Johns heads,and intake, headers. Carb is a bit in the air, if the budget will take it a Quick Fuel Technologies 750 tweaked for street use. The above cam should give 16 in of vacuum at Idle and be very smooth.

When I build an engine I want to leave as little on the table as possible.

I did put Ted's engine as described in the latest Y block mag into the EAP Pro software and came up with almost Identical results.

The soft ware engine made the same horsepower but gave up 500 RPM sooner. This is probably because I guessed at his header dimensions. 

New cam design revolves around the use of either roller lifters or overhead cam construction. The head has nothing to do with this as it doesn't address any of these functions. Although I do conceed that there will be developments in line with the release of the heads.

I would be disapointed if the heads didn't fit abroad range of applications as a potential customer I don't see myself at ether end of the range and would like the freedom to build an engine around what I need and want.  

I agree entirely that modern valve timings have improved. The faster and wider a inlet can open the better the VE of an engine. This is the advantage of overhead cam that because of a lack of valve train weight the faster you can open the inlet because of reduced inertia.  This not only increases the time a valve is open at it's maximum it also optimizes the ram effect and uses the pressures that occur in the inlet port when closed.

The new heads don't affect any of the currently available valve train componentry. You have avenues to explore where, you can as you say, either choose to grind your own cam or use an existing can with hi ratio roller rockers.

I like higher lift cams I've had a few engines where either the existing cam or the one I've chosen is of relatively modest duration but of higher lift than other cams that are available from other companies. I think it tends to broaden the power band. Some of these engines have felt as though they are bigger than they are.

Lift can be at odds with one of my other preferences reliability. All machines are a compromise of function over use.  

This is not a new head issue, this is an issue with most Y cams.

Using the software to experiment a gain of 30 HP can be gained by increasing lift from .400 to .550 with the new heads based on Ted's engine. The old heads may not gain very much if the airflow gains stall at lifts above .400. Please remember the new heads peak at .550 valve lift.

As to reliability, pushing the limits by raising acceleration rates on the valve train can lead to lubrication failures at the cam/lifter interface. Lifts of .500 are common and reliable with longer duration cams. As the duration shortens and acceleration to achieve the lift increases reliability becomes more marginal.

The test results of the EMC engine should be very revealing. the higher lift cam used on this engine and the added displacement should really test the new heads.

The soft ware is not an absolute but it is a strong indicator of directions to take during an engine build.

Remember I was able to very nearly duplicate the results of Ted's engine with this soft ware (hp peak was within 2, peak rpm off by 500 rpm).

You do understand the The Y has mushroom lifters, the ramp cannot be as newer roller lifter ramps can be due to the fact you would break the head of the lifter or it would dig in to the ramp severely accelerating the wear of these components, not to mention wear the lifter guides.

The program you are using to do your calculations may not be adding into the equasion that the Y is a solid mushroom lifter only, so ramp angle is limited on these.

The mushroom on the Y is larger than diameter of lifters of even the Chrysler Corp. engines. This aids in its ability to handle more agressive ramps.

The concern with the Y is the small stem verses the dia of the head and the possibility of flexing/fracture at that juncture.

I do know of one Y built with the agressive ramps I want. It worked OK.

Light weight valves and retainers. Titanium will greatly reduce the component weights and valve spring tension required to keep everything under control.

Well designed cam lobe. Some designs are harder on parts than others with the same basic specs.

Sufficient valve spring pressure. Nothing will break lifters quicker than weak valve springs.

Higher lift is harder on parts. Longer duration is easier on parts.

Keep in mind that better cylinderheads will make the same power at lower compression ratios and with smaller cams.

On your site you have a range of cams. These are referenced to a spring. Firstly what cam are the springs, that are sold with the heads, designed for and Secondly do you offer other springs for specific builds? 

The springs in the new heads will handle up to .520" lift but are not the same as the VS115.

Thanks

The EAP program will evaluate valve train stability if the componet weights and cam profile is entered.

Just my opinion, but...

Without the weight of a rocker or pushrod the designer doesn't need to be very careful about jerk and rapid acceleration changes. Some of worst cam designs I've ever seen were from late model Japanese ATV's. No way you would want to use them in a pushrod engine.

With regard to lobe separation, we recommend 108 for engines with headers, 110 for engines with fair headers or very good dual exhaust and 112 for restrictive exhaust. I'm not a hugh fan of wide lobe separation cams such as 112 or more. Generally, low RPM power suffers particularly if the engine also has low compression. Exhaust will also noticeably louder under full throttle.

I just checked a 216 @ .050" Crower hydraulic lobe against our Y265S  224 @ .050" mechanical lobe. Both have .280" lobe lift +-.002". When figured with .006" lash for the hydraulic and .018" for mechanical cam the timing at the valve was essentially identical. Due to the difference in lash you must use 8-12 degrees more for a mechanical cam when using your software or seat of the pants speculating what size cam to use.

I have sold well over 100 of the Y265S Y-Block cam and no one has ever complained that it was too big, even with a FOM trans.

My wish list may not be practical, but this is my thing. I tried to push the practical technical limits by asking "can we do this?" during my engineering career, and find it hard to back off now that I have retired.

A lot of people would argue that building aluminum heads for a Y-Block is not a wise thing to do. I chose not to listen to them.

John,  you have proven that it was possible to do and have the HP increase to back it up. I hope the orders are coming in, let me know when mine are ready, thanks from everyone here! regards bill.

 My application is a very mild street application. The thought process I am going through may be applicable to others that have a different set of parameters. Ted has obviously has pushed the limits on extreme performance with his EMC entry and the dragster engine.

My main thrust is to explore the limits of the camshaft/lifter interface. 

Since John has adresses the airflow issues this appears to be the next problem in building an exceptional Y.

   There was/is a certain amount of insanity involved in this project. I can tell you that the only SpeedSmith left in the project is the name on the sales receipt. Everything else is Mummert. I have personally seen flow bench results that are pretty impressive. And you can carry one around the garage in ONE hand. The amount of work time and investment John (and son Jeff) have put forth is tremendous. We're talking two guys in a small shop, NOT a large corporation with limitless capital and resources. Congrats are in order, the finished product will be worth the wait, I hope that we all apreciate this effort. 

The Y-block does have a large lifter for a domestic V-8. Things you will want to keep in mind when trying to push the limits of lobe velocity are.

1. Chamfer on the edge of the lifter.  More chamfer less useable lifter face.

2. Lifter bore centering over the lobe. The farther off center it is the less useable the lifter face becomes.

3. Acheivable nose radius on the cam. Short duration, high lift cams will have a small nose radius. Making them RPM limited. They almost always get pitting on the nose of the lobe. Not neccesarily going flat but just but just tramatized do to high spring rates with high velocity lobes and small contact area, nose to lifter.

4. Spring rate, rate in a spring is stored available return energy.  Two spring set ups can have the same open pressure but one can have considerably less return energy. Example.  120# on the seat and 320# open @.500"  200# gain over .500 lift is a 400# rate per inch.  This will have more nose control than a lower rate setup. Say  145# on the seat and 320# open  is a 175# of stored energy over the nose. 350# rate per inch

5. Lobe dynamics are the biggy on the list. The main reason is that these harmonics get transfered through whole valvetrain. Especially your pushrods. Pushrods have been one the biggest culprates to unstable valvetrain and many times the springs get the blame. Don't get me wrong you can be under sprung.

Like I said earlier pushing the limits of the lifter face can done safely as long you are looking at everything much closer.

In the end it all call comes down to valve events. More modern attempts have been tamer lobes and more rocker ratio to acheive the desirable valve events

 When done right they both work well.

      The valve events and geometry can be discussed there. It is an area that can be explored now, there wasn't much point prior to the new heads since the port airflow stalled at relatively low lifts and rates with the iron heads. The Mummert head changes the ball game. I think it's safe to say the limits of the iron heads have been explored to death by John Ted and others. None of the cam timing, profile or lift theorys help much without ports that carry increased airflow.