7M meet Technology!

[sethron71]

Well since I am a die hard 7M man I am always looking for ways to better these beasts and here is my first step at some high tech head work:

Let me know what you think and all your head gurus tell me what is best in modifying the cylinder head bowl. Basically all I a have done is increased the size by .050" and kept the essence of design just to remove all the casting. No real material removal for the most part.

Next I will be attempting the ports but I have to have special tooling made because I only have a 4-Axis Haas and the negatives in the ports obviously require undercuts which are impossible on a 3 or 4 axis machine like I have with out special tooling.

Also note in my last design a few minutes ago the ridges in the bottom are gone as well as the weird lip at the top, so I will make another one on my next free night and then I will throw a head in there and give it a try!

Hope you enjoy,
Seth

 

[NashMan]

hummmm trying to smooth it all out to get rid of hot spots?

 

[bioskyline]

intersting, so the head chamber would be increased? very intersting.

 

[sethron71]

More then anything....Real goals are:

1) Remove all the casting, completely smoothing the bowl
2) Make every bowl identical

Increase in bowl size is minimal with roughly on .050" being removed, although I may have to go a bit deeper to remove all the casting.

Seth

 

[mecevans]

Will you be doing custom cnc head work? only ever seen people get it done by hand for 7M's.

 

[suprarich]

Reminds me of an S&S Cycle Harley Combustion chamber. They made a piston to match the head too. Looks good.

 

[bioskyline]

sounds good, cant wait to see one done on a head.

 

[hvyman]

At this rate in a couple years you will be making your own heads :rofl:

Looks good, cant wait to see this finished.

 

[sethron71]

Thanks guys, depending on how things go tonight I will try it out on a head!

@Rich.... What do you think about putting a radius on the top sharp edge as well straight lining that peak in between the valves? I assume it is just there to reduce volume and keep compression up? Or does it have an affect on swirl in the chamber to help gasses flow through the head properly?

Thanks,
Seth

 

[Enraged]

wow. awesome work, as usual.

 

[mecevans]

I think it helps swirl. I hosed off my head after the hot tank and i stuck the hose into the intake port. I was pretty cool how it came out the valve and bounced off that hump and made it swirl.

 

[NashMan]

^ yup that is right


the only issue with hogging the head like so is not every head is the same at all in casting so you will haev to make alot of diffent sizeing tell they all match


and if you can remove you can all ways replace with coatings to make up a tad of the diff

 

[sethron71]

Well I did a cylinder tonight! Going to take a little reworking. Will have to use a smaller radi bit to get into the tighter corners and have a coupe programing issues to iron out but looking promising:

Seth

 

[hvyman]

Thats fucking sick. Are you going to test 1 out on your car? How much do you think you would charge for taht?

 

[bioskyline]

Thats fucking sick. Are you going to test 1 out on your car? How much do you think you would charge for taht?

+1 on that, looks very very good. i also want a price on that (approximate, dont have to bee dead one)

 

[Dimman]

What about chamfering/radiusing the spark plug hole? Would this help flame propagation?

 

[hvyman]

The spark plug comes up more than that. Its prolly out of the way for machining.

 

[suprarich]

Thanks guys, depending on how things go tonight I will try it out on a head!

@Rich.... What do you think about putting a radius on the top sharp edge as well straight lining that peak in between the valves? I assume it is just there to reduce volume and keep compression up? Or does it have an affect on swirl in the chamber to help gasses flow through the head properly?

Thanks,
Seth

That is there for swirl, but it was more designed for the na than the turbo. Higher boost pressures will begine to negate the effect of that hump. Ultra high flowing nitro methane heads on my pro fuel bike, we do not have any type of hump to direct the flow of air. We taylored the chamber around the shape of the piston to try and make the squish as even as we could over the top of the piston. The 7m does not do this at all and the head was never intended for aftermarket pistons. I have done what you are doing before and the results speak for themselves, so you are going in the right direction for sure. What you will also want to look at is getting a piston made that will work with your combustion chamber better. All aftermarket pistons are just designed around the oem piston. I had dome pistons made for the last head that was built like this.

 

[mecevans]

For a street car is it worth removing the hump?

 

[hvyman]

Didnt the group a cars have just a round combustion chamber?