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-   -   Options for "camshaftery" on VVT head? (https://www.miataturbo.net/engine-performance-56/options-camshaftery-vvt-head-49645/)

NickC 07-16-2010 01:28 AM

Options for "camshaftery" on VVT head?
 
So there was this 2001 cylinder head on ebay with valves but without camshafts or shims/buckets and I had to have it for $80 shipped. What are my options for camshafts? I'm pretty sure anything 94+ will work, but I'd really like to have all of the components for VVT and I honestly just don't know what I need to be e-scrounging for exactly. Upon receiving the head, it appears that he had blocked off an oil passage utilizing a metal sphere/BB similar to what you're supposed to shoot out of a slingshot and there are 3 "press marks" holding it in place. I'm assuming that hunk of metal thing on the left in this ebay link is supposed to be fed oil from that passage but why come i not know where cam go there?

Savington 07-16-2010 02:00 AM

You need a VVT-specific intake cam, a standard cam will not work. As for the rest of it, it's impossible to visualize from your description so take lots of good photos for us.

At the end of the day, you're better off buying a complete head, unless you were planning on dumping several hundred bucks into porting, SUBs and custom cams.

NickC 07-16-2010 02:21 AM

If I don't go VVT, I think I can use a standard intake cam and timing gear though, correct? I "priced out" what it would cost to complete this head and it was close enough to a complete head to justify the "$80 risk"

Savington 07-16-2010 03:12 AM

No, you cannot use a non-VVT intake cam in a VVT head for any reason. If you don't believe me, feel free to buy a non-VVT intake cam - the second you attempt to install it, it will be painfully obvious why you cannot do it.

Since you've priced it out, I assume you've already priced out the cost of the valve cover, spool valve, solenoid, pigtail connector, and OEM oil line? You need all of that to use the head. You cannot just run a standard valve cover since the front cam journal is oiled via the VVT. Your factory plug wires won't fit, either - you'll need to either drill the valve cover or source 01+ coils and wire them in.

As much as it sucks, I think you got ripped off. Unless you already have a working VVT setup, an $80 VVT head without cams or buckets is a headache just waiting to be unleashed. There is a long list of items you'll need to source, assuming that head isn't warped or otherwise damaged, and by the time you've sourced everything piecemeal you'll have spent more than you would just buying another head.

How are you planning to control VVT?

NickC 07-16-2010 04:32 AM

Well... that sucks at least for a non-VVT cheap option (cost estimations were based on being able to use standard cams) . I guess worst case I could try to lathe something up to adapt-a-cam or have an $80 reason to build a flowbench...

Optimism:
If stock is too expensive, then UPGRAYEDD.
I plan on doing COPs, maybe I can adapt a standard valve cover? or I'll buy one, wiring is simple enough you can always solder on pins etc. one time I even chopped up a mazda 3 computer just to interface an rx-8 pcm with an NC body harness ^_^
Spool valves look pretty easy to make, I'm not super-fond of how slow the stock one is and am curious how that affects transient valve timing "states", I may do a faster dual-solenoid one where "lock" is default.

As far as control, I "dabble" in DIY microcontrollers and circuitry, but this will be investigated further. There seems to be a very good controller in the works for production, but if I insist on being unique and doing that dual-solenoid spool valve it probably wont work for my application.

I've been doing a fair amount of searching/reading on VVT and I think I have a pretty good understanding of what needs to be done now that my fears of hard-to-get hardware are confirmed by more than "hmm, everyone uses 99-00 heads, is VVT that much of a bitch?"

shuiend 07-16-2010 06:36 AM

Here is a picture of my VVT Head that shows the Intake Cam and why it is different.
http://www.boostedmiata.com/gallery2...0+21_06_49.jpg

shuiend 07-16-2010 06:38 AM


Originally Posted by NickC (Post 602238)
I plan on doing COPs, maybe I can adapt a standard valve cover?

I had to drill out the center holes to fit my cops and today I plan on cutting off some other things to get COPS to fit in my Valve Cover. I will try to get a picture tonight of what all had to be done to make standards COPS fit.

Savington 07-16-2010 01:56 PM


Originally Posted by NickC (Post 602238)
lathe something up to adapt-a-cam

Still not possible, look closely at the front cam area on the photo that was just posted.


Originally Posted by NickC (Post 602238)
Optimism:
If stock is too expensive, then UPGRAYEDD.
I plan on doing COPs, maybe I can adapt a standard valve cover?

Again, not possible, the front cam journal is lubricated through the VVT system, it must be in place or you'll destroy the head

Savington 07-16-2010 01:57 PM


Originally Posted by shuiend (Post 602244)
I had to drill out the center holes to fit my cops and today I plan on cutting off some other things to get COPS to fit in my Valve Cover. I will try to get a picture tonight of what all had to be done to make standards COPS fit.

Lars, lemme know if that works. I was worried about cutting through the cover to remove all the OE coil mount points. It would definitely be much cleaner.

shuiend 07-16-2010 03:08 PM


Originally Posted by Savington (Post 602475)
Lars, lemme know if that works. I was worried about cutting through the cover to remove all the OE coil mount points. It would definitely be much cleaner.

Here is the valve cover with the holes drilled out. I used a 1"1/8 hole saw on my drill press at work to do it. They are not perfect, but close enough for my to be happy. The 2 knobs that are black are the 2 I plan on cutting down in a little bit. With the cops I have I just need to but cut those 2 and then cut off a little off each cop and it should work. I will get more pictures when I finish.

http://www.boostedmiata.com/gallery2...-2/vcuncut.jpg

shuiend 07-16-2010 05:50 PM

So I ended up cutting off more then I expected. My machining skills are not that great and it looks like shit, but it should work fine for me.The 2 nubs that I painted black and the 2 between them ended up getting cut down. I started with an angle grinder and then moved to a dremel. The nubs do not connect to anything inside the VC so as long as your do not remove to much you should be fine.

http://www.boostedmiata.com/gallery2...60-2/cutVC.jpg

NickC 07-16-2010 11:04 PM


Originally Posted by Savington (Post 602474)
Still not possible, look closely at the front cam area on the photo that was just posted.



Again, not possible, the front cam journal is lubricated through the VVT system, it must be in place or you'll destroy the head

Yeah, adapting a non-VVT camshaft appears to be non-trivial, but still not convinced (although deterred) on the valve cover. The actual journal is solely part of the head, I'm assuming I have enough dremel skillz (and subsequent large amounts of silicone gasket) to fit the older valve cover then weld in aluminum bosses for the oil coming in

Savington 07-19-2010 03:52 PM

I don't have any more advice for you. Good luck.

shuiend 07-19-2010 03:57 PM


Originally Posted by NickC (Post 602746)
Yeah, adapting a non-VVT camshaft appears to be non-trivial, but still not convinced (although deterred) on the valve cover. The actual journal is solely part of the head, I'm assuming I have enough dremel skillz (and subsequent large amounts of silicone gasket) to fit the older valve cover then weld in aluminum bosses for the oil coming in

Why not buy Doppgangers VVT VC that he has for sale in the classifieds?

y8s 07-19-2010 04:17 PM


Originally Posted by shuiend (Post 602673)
So I ended up cutting off more then I expected. My machining skills are not that great and it looks like shit, but it should work fine for me.The 2 nubs that I painted black and the 2 between them ended up getting cut down. I started with an angle grinder and then moved to a dremel. The nubs do not connect to anything inside the VC so as long as your do not remove to much you should be fine.

http://www.boostedmiata.com/gallery2...60-2/cutVC.jpg

That's gotta be a better way than what I went through:

http://farm3.static.flickr.com/2027/...04ac955d_b.jpg

NickC 07-19-2010 08:09 PM


Originally Posted by shuiend (Post 603713)
Why not buy Doppgangers VVT VC that he has for sale in the classifieds?

Didn't see it! PM sent =)


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