CB's CNC heads

[slowsixtyduece]

Hey all- i was wondering if anybody has used CB's o44 cnc'ed heads lately- Results? I think i might put some cnc 42x37 valve heads on my 1915 w/ an fk-8 cam, and dellorto 45's. Are they pretty nice or what? anybody have them on their motor? motor specs, hp or quarter mile times would be greatly appreciated... thanks

[evil_vw]

the heads are nothing more than 044's which have been cnc ported rather than hand ported. as far as my investigations have discovered, there are no other differences. same castings, same valves and sizes, etc. its like everything else- the heads are only as good as the motor they go on, its all relative. cnc porting, imo, is really no better than a quality hand job (no pun intended) with regards to engine performance. im sure they are good heads, dont get me wrong. but worth the extra $$$????

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"OK, got the duct tape, JB weld, bailing wire, and a big hammer- everything should be fine."

[flatfour]

I have a set and they are tough to beat for the price.

[Kevin Reynolds]

[QUOTE]Originally posted by evil_vw:
dont get me wrong. but worth the extra $$$????

No flame intended here, but I would like to know who's port job are you getting for less than $700.00 a pair?

[evil_vw]

hmmmmm.......you have a good point. why was i thinkin the cb cnc ported ones were like $1200?? where the hell was my head on that one?? you're right-- they're only $700, which is a decent deal. REALLY good hand porting can run upwards of $1500!!! i guess i was only considering the quality and content of the heads and had stuck in the clay-like mass i call my brain that they were $1200 heads!

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"OK, got the duct tape, JB weld, bailing wire, and a big hammer- everything should be fine."

[VGM]

Havent seen them run yet-but have held them in my unworthy hands.Porting is same but even better than a set of under-cooling-finned and unstreetable competition eliminators I have on the shelf to compare.These are a steal at $700.Its the kind of deal you should fear wont be there tomorrow when you wake up from the dream.I wish I could afford ten sets,I know I wouldnt be sorry later.If these get taken off the market from intercompany lawsuit wars,it will be a real shame.

[JoeSumen]

Hi Guys.
In reference to the "CB-CNC 044". These heads are wonderful. Though a couple of areas can be addressed by minor hand finishing resulting in maximum benefit. What is of key importance is, once these heads are "jigged" in the "CNC" indexing fixtures, we have VERY PRECISE repeatability from hole-to-hole. As we all know, labor is expensive, specialized labor even more so. 85% of the hand labor can be accomplished in an amazingly short period of time utilizing the "CNC". I know a LOT of you have taken a shot a porting. YOU KNOW how much time is involved in metal removal while maintaining some degree of accuracy. Now. Muliply that by the number of ports and you`ve spent A LOT OF TIME! The "CNC" in concert with the programmer, who determines his data input from the port designer truly is THE WAY to do it. Some special tooling had to be developed. There are actually three numerically controlled mills. One profiles ONLY the combustion chamber, another profiles the intake port from the chamber side. The third contours BOTH ends of the exhaust port AND the intake port from the manifold side. The head is rotated three times, from start to finish. These heads are a testament to applied technology. With very little end work, they are astonishingly good. And remember. If for some reason you grenade a piston, drop a valve, or in any way destroy a head. You simply get a replacement GUARANTEED to be a duplicate in a relatively short period of time. In my opinion, for their given application. They are indeed a bargain.

[Searoy]

After looking at their web site, it appears that they are $700 each. That's $1400 a pair, or are they the unbelieveable $700 a pair price?

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*** Teach a Man to Fish ***
Darth Searoy

"I tend to lean toward a tighter gap and a
looser skirt....a little slap never hurt." --
Joe Locicero a.k.a. Joe of the West

[type34sunroof]

no they are 700 a pair.

[flatfour]

They are definately 700 a pair. I bought a set about a month ago. About another 100 or so for their match ported Big beef manifolds.

[vdubsinjensen]

They are $700.00 a pair,and worth every cent.I just put em' on a 2165 and they work great!As for a little clean-up on the ports,they're pretty nice without it,and I don't believe you would gain much for the time spent.

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65'sunroof 2332 58'double-door panel 59'vert' 77'Westy 73'Superbeetle dirtrack racecar 57'tube-frame dragbug(hanging from the ceiling)

[Dexter]

Well, for your $700 you can get:
AJ Sims "Street Port" 044s- 181CFM@25" intake at .650
OR
CB CNC UMP Heads- 205CFM @25" intake

The CBs seem a better deal...

[rcb78]

Just remember more flow isn't always better. Port velocity plays a huge role too. Hand port jobs are awesome because you can tell your head porter about your engine and driving needs and he'll port the heads accordingly. I've got the above mentioned 044s ported by AJ. I just told him what I had right now and what I had planned for the next engine and he set them up accordingly. I think the biggest benefit of CNC porting will be when the head gurus use a CNC ported head as a baseline and then do the finish work by hand. You'll end up with a custom head for a lower price because they won't have to waste time ($$$) grinding the basic port shapes. I think we're close, but not quite there yet. --Ryan

[Puck]

Repeatability is also a key. You know that from port to port the flow is going to be the same and the added benefit of replacement if you trash a head.

[Island bugs]

One of the key elements of head performance appears to be the ratio of intake to exhaust supposedly more important than gross intake flow. I belive a good head porter will try to achieve as close to an 80% ratio of exhaust to intake flow. How do the CB heads spec out in this regard ???