Need head advice. - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


Engine Performance This section is for discussion on all engine building related questions.
Sponsored by:
Sponsored by:

Reply
 
 
 
LinkBack Thread Tools Search this Thread
Old 09-02-2010, 11:56 AM   #1
Elite Member
Thread Starter
iTrader: (39)
 
Zabac's Avatar
 
Join Date: Sep 2007
Location: High Point NC
Posts: 4,854
Total Cats: 8
Default Need head advice.

Looking to buy a 99/00 head that I desparately need from a reputable seller.
Seller states that the head is slightly warped:
"Slightly warped (just under 15 thousandths), but have been told by the CarQuest machine shop off German Town road that it can be fixed just fine for less than 100."
Give me the grain of salt!

Thanks,

Daniel
Zabac is offline   Reply With Quote
Old 09-02-2010, 01:05 PM   #2
Junior Member
iTrader: (4)
 
Join Date: Dec 2006
Location: Charlotte , nc
Posts: 325
Total Cats: 1
Default

I wouldnt be worried about a slight warped, Any head I pull and replace, goes to the machine shop and gets flattened anyways ... Just costs hundred bucks. Those heads however have been know to eat up cam journals from the bottom end going bad. Inspect closely. Do some research on what causes the damage and what to look out for there. I read about another local Charlottean (Miatamania) that got a a bad 99 head unuseable. Also depends on price before machine work needed. Perhaps a second opionion / warranty options.

Goodluck Dan
jedduh01 is offline   Reply With Quote
Old 09-02-2010, 01:40 PM   #3
Elite Member
Thread Starter
iTrader: (39)
 
Zabac's Avatar
 
Join Date: Sep 2007
Location: High Point NC
Posts: 4,854
Total Cats: 8
Default

"Cylinder head, valves, keepers, springs, retainers, lifters. No cams, gears, valve cover or sensors."
Price is right and i have a connection with a good local machine shop for all the work.
With no cams in place, how can I inspect for the journal damage? just look for scoring? but bearings are probably removed as well...
It is a reputable seller, so i'm wanting to take the chance...
Zabac is offline   Reply With Quote
Old 09-02-2010, 01:50 PM   #4
Senior Member
iTrader: (9)
 
Join Date: Oct 2006
Location: Lexington SC
Posts: 1,003
Total Cats: 14
Default

Check those cam journals! If there is obvious damage you should be able to see scoring marks. Also measure the diameters to see if they are within spec.
A machine shop can remove enough material to get a badly warped head flat again but the cam journals can't be fixed, a few thousanths misalignment can cause issues. That overall misalignment is alot harder to measure and is the reason why I have walked away from two seemingly cheap heads. The cost between a cheapie head and one that is in good shape usually isn't that much. Unless you get it for free that is.
You risk eating up good cams too if you are supplying your own cams, which can add to the risk of running a warped head.
Just my
Rallas is offline   Reply With Quote
Old 09-02-2010, 02:09 PM   #5
Elite Member
iTrader: (8)
 
Join Date: Jun 2009
Location: Albany, NY
Posts: 1,523
Total Cats: 4
Default

Cam journal damage is very obvious, ask how I know.

My machinist said he could fix mine by 'dusting' the caps and journal towers then align-boring the journals again. Then, either source different cams or polish the old ones down a bit. Sounds like voodoo, I probably wouldn't do it, but it's there as a possibility. The work exceeds the price of another used head, I'm sure. BTW, price on new head from mazdaspeed wasn't that bad, either, iirc.
webby459 is offline   Reply With Quote
Old 09-02-2010, 02:34 PM   #6
I'm Miserable!
 
SlideRuler's Avatar
 
Join Date: May 2010
Location: NJ
Posts: 494
Total Cats: -6
Default

I think the most painless, though possibly a tiny bit more expensive option, would be this:

http://flyinmiata.com/enginebuilder/head.php

I'd rather pay a bit more for quality and ease of replacement than deal with any warpage or any other BS.
SlideRuler is offline   Reply With Quote
Old 09-02-2010, 02:44 PM   #7
Elite Member
Thread Starter
iTrader: (39)
 
Zabac's Avatar
 
Join Date: Sep 2007
Location: High Point NC
Posts: 4,854
Total Cats: 8
Default

Can you test the alignment without the cams? I'd assume so...
I guess best bet is to make conditional purchase, pending my shops approval.

My mashinist is pretty good, done lots of work for me and my friends, so I trust his word, and he's beyond reasonable, that's why I can't just pass on this head.
Zabac is offline   Reply With Quote
Old 09-02-2010, 02:48 PM   #8
Supporting Vendor
iTrader: (31)
 
Savington's Avatar
 
Join Date: Nov 2006
Location: Sunnyvale, CA
Posts: 14,363
Total Cats: 1,323
Default

Have a shop check the cam journals, if they spec out and it really is only .015" warped (instead of that being a "guesstimate" and oh oops its .040 out) then it's probably OK.
Savington is offline   Reply With Quote
Old 09-02-2010, 02:52 PM   #9
Elite Member
Thread Starter
iTrader: (39)
 
Zabac's Avatar
 
Join Date: Sep 2007
Location: High Point NC
Posts: 4,854
Total Cats: 8
Default

Quote:
Originally Posted by Savington View Post
Have a shop check the cam journals, if they spec out and it really is only .015" warped (instead of that being a "guesstimate" and oh oops its .040 out) then it's probably OK.
That's what I'm thinking.
We'll see what shop says, but the head is only $140, can't resist at that price.
Zabac is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Project Gemini - Turbo Civic on the Cheap Full_Tilt_Boogie Build Threads 58 Yesterday 10:04 PM
Another Cast Manifold Corky Bell Prefabbed Turbo Kits 18 11-22-2016 10:01 PM
Bad head gasket or ? shooterschmidty Engine Performance 8 09-30-2015 11:28 PM
Another Alternator thread ihiryu General Miata Chat 9 09-28-2015 11:22 AM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 10:53 AM.