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Home brew head work

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Old 08-30-2007, 05:25 PM
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Booyah!!
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Old 08-30-2007, 09:11 PM
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wow! Time for a T4 compressor!
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Old 08-30-2007, 09:27 PM
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definatley a stronger response, is that on ebc running for 8psi or is it on normal WG? If it is on WG that is impressive.
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Old 08-31-2007, 09:00 AM
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Originally Posted by Newbsauce
Speaking of this.. if anyone has a spare head I would definitely take it off your hands
i think fm has them in their salvage for cheap/free, worth a check.
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Old 09-01-2007, 06:40 PM
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http://filebox.vt.edu/users/gouldmab/Engine/

Thats the link to my head. Those pics are once I got it back from the the coaters. It has ceramic chamber and exhaust port coatings. It also shows pictures of it "assembled" so I could measure for lash caps needed for the shim under bucket lifters. Sadly, I don't have my valve stem seals yet so I'm going to have to fully disassemble it to put them in :( Thats basically what the head will look like fully assembled though. With that setup I can rev out to 9k, but it will remain to be seen if those cams will make me power up there. They are a custom grind from integral cams. Once I get more parts in I'll make my own build thread, I'm just posting this here because I did this porting myself.
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Old 09-28-2007, 08:30 AM
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Ben,

I finally got you a good log!

this is a log of my lastest pull as of this morning vs. my last dyno run a few months ago.

the only change in the system now is a fresh block, the headwork, and a gutted cat. This is using the same MBC at the same adjustment point as when i removed it:




I make 12psi 500RPM sooner based on this chart. all my dyno logs show me making 12psi at 4400, now it logged on the street this morning 3880-3900 everytime. it feel so much improved, has greater low-end, and as you can see by the chart makes 86mph about 3 seconds faster, and you can clearly see the boost is peaking higher at redline to 13.5psi.
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Old 09-28-2007, 08:49 AM
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Woot!11
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Old 09-28-2007, 08:59 AM
  #28  
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pretty incredible, definately worthwhile... and imagine you'll get another bump in spool with your exhaust.

unfortunately, the head I was going to get ended up being vaporware.
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Old 09-28-2007, 10:45 AM
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When I unshrouded the valves in my head, I cut 20% of the diameter of the exhaust valves out and 25% of the intake valves. Note, you can't take metal away where the headgasket seals, but on the two 'flats' in the outer circumference of the combustion chambers, where the headgasket is round and the flats are not, you can remove metal. Those numbers above are for a NA motor. I would go 30% exhast 35% intakes on a FI motor, since the loss of compression is not as critical and you will see more flow.

I also polished the valves by spinning them in a drill press and using a dremel to slightly reshape them, and then polish them.

I didn't take any pics of the headwork, and I wish I had, but here's a drawing illustrating where I removed metal. The dotted line is where the headgasket seals.

Name:  deshrouded.jpg
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Old 09-28-2007, 04:06 PM
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How does a reworked NA head compare with a 99-01 head power wise?

From what i've seen a stock NA head to a stock 99-01 head seems to gain around 20bhp.

What about fitting a reworked 99-01 head?

If the posts i've seen are right and you do get 20bhp from just the head, then surely it makes more sense time and money wise to just swap em over?



Cheers
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Old 09-28-2007, 04:10 PM
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Engine in question is a 1.6, so swapping a 99-01 head on doesn't work very well
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Old 09-28-2007, 04:16 PM
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the 99-00 head is the bp4w head. compared to the older bp head it has a few improvements that result in better intake airflow and better high rpm durability. this is the head that is an easy bolt on affair to an older bp motor. some of this improvement is due to a higher intake manifold and better, straighter angle for the intake charge to get to the combustion chamber. this head could still be worked to get even better flow. Oversized, unshrouded intake valves should make a nice improvement. the difference between a stock na 1.8 head and a stock 99-00 head should be dramatic, and then working the 99-00 head should be even more amazing.

the 01+ is still a fine head, but has hydraulic variable cam timing, and as far as I know the only non oem ecu that controls it is the Hydra.
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Old 11-20-2007, 12:30 AM
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so exactly what tools are needed to do a port/polish on a 99 head? I already have the dremel and have done this sort of thing before on small gas engines, but never on my Miata.
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Old 11-20-2007, 12:49 AM
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This is one of those things where I firmly believe that if you have to ask then you shouldn't be doing it. Also, being as 99 heads dont go for cheap I wouldn't make it my first.
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Old 11-20-2007, 10:37 AM
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Originally Posted by neogenesis2004
This is one of those things where I firmly believe that if you have to ask then you shouldn't be doing it. Also, being as 99 heads dont go for cheap I wouldn't make it my first.
hah, dont be a weenus. i have no prior porting experience nor a die grinder and I plan to dive right in to my spare 01 head. i do have the porting kit with all the abrasives though. just nothing to stick it in... it wont fit the 1/8" collet of the dremel.
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Old 11-20-2007, 10:39 AM
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I was watching them port heads on Street Tuner Challenge!
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Old 11-20-2007, 11:48 AM
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Originally Posted by y8s
hah, dont be a weenus. i have no prior porting experience nor a die grinder and I plan to dive right in to my spare 01 head. i do have the porting kit with all the abrasives though. just nothing to stick it in... it wont fit the 1/8" collet of the dremel.
HF sells mini pneumatic die grinders. Last i check Big Lots also sold an electric ching chong die grinder.
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Old 11-20-2007, 01:13 PM
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let me clarify, my question isn't what is needed for the actual port and polish, but what tools I need to take the related parts apart and put them back together. I read Hakunas article on the DIY port/polish, and apparently I need to take off the valve train, cams, etc. I am confident in my ability to do this, I just need to know if there are any specific tools needed to do this. If so, what are they?
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Old 11-20-2007, 01:16 PM
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12 point sockets
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Old 11-20-2007, 02:16 PM
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hey scott, did you take any before pics?
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