Head build-Modified - 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. KMiata

LinkBack Thread Tools Search this Thread
Old 05-23-2012, 08:58 PM   #1
Senior Member
Thread Starter
iTrader: (1)
BogusSVO's Avatar
Join Date: Mar 2012
Location: Pensacola Fla.
Posts: 560
Total Cats: 185
Default Head build-Modified

It helps if you have read "What happens to a head in a machine shop"

What Happens to a head in a machine shop

That will cover the basics

Head Build Modified

I am going to skip the tear down and tech, and start, a basic clean casting.

The guides are good, and I am going to use the customer-supplied parts.

>Manley single springs, Spec sheet 66 lbs @ 1.580
>EPN-Engnbldr Std size Stainless Steel valves

This head was also Belt surfaced, So I have to do a corrective mill to square the head.

I set it up on the grinding bench

I know this head will see turbo use.
I inked parts around the combustion chamber and etched with a head gasket.

Did oil port Mod 1

The sharp edge of the combustion chamber was beveled down

A slight champher was done around the rest of the combustion chamber

The runners had some cast flashing removed

Now was time for the valve job, start with a basic 3 angle valve job

Checking seat placement on the valve.

Now I will do a throat cut.

Notice the difference this makes, See the lip under the seat insert with the rough casting, (left bowl)

The bowl on the right had the throat cut.

This leaves a lip also

Now the lip needs remove and blended in.

The valves are ground.

Then lapped in and back cut

The head is CBN milled

First cut .003

Another .004

I milled another .002 to finish square the head.

Had a bad exhaust stud hole, so a heli-coil fixed that.

Valve tip height is checked,
The springs are checked
Spring installed height is measured.
Springs will be installed at 1.530 @ 80lbs

Shims are placed on the head.

Then the stock spring pad and Vition blue stem seals.

Springs are then buckled up .

The head is now ready for HLAs, followers, and cams and cam caps.
Attached Thumbnails
Head build-Modified-dscf6323.jpg   Head build-Modified-dscf6327.jpg   Head build-Modified-dscf6330.jpg   Head build-Modified-dscf6331.jpg   Head build-Modified-dscf6332.jpg  

Head build-Modified-dscf6335.jpg   Head build-Modified-dscf6337.jpg   Head build-Modified-dscf6336.jpg   Head build-Modified-dscf6339.jpg   Head build-Modified-dscf6344.jpg  

Head build-Modified-dscf6345.jpg   Head build-Modified-dscf6348.jpg   Head build-Modified-dscf6354.jpg   Head build-Modified-dscf6357.jpg   Head build-Modified-dscf6371.jpg  

Head build-Modified-dscf6386.jpg   Head build-Modified-dscf6358.jpg   Head build-Modified-dscf6362.jpg   Head build-Modified-dscf6364.jpg   Head build-Modified-dscf6401.jpg  

Head build-Modified-dscf6399.jpg   Head build-Modified-dscf6400.jpg   Head build-Modified-dscf6402.jpg  
BogusSVO is offline   Reply With Quote
Old 05-23-2012, 10:13 PM   #2
Senior Member
Thread Starter
iTrader: (1)
BogusSVO's Avatar
Join Date: Mar 2012
Location: Pensacola Fla.
Posts: 560
Total Cats: 185

I will have to guess that if you are reading this thread, that you are looking to do something a little more than stock.

This is another good thread with links to 1.8BP heads ported by the pros.


Good info in there that may help with a DIY head port job.
BogusSVO is offline   Reply With Quote
Old 05-30-2012, 10:55 AM   #3
Elite Member
iTrader: (12)
Join Date: Dec 2006
Location: Taos, New mexico
Posts: 5,659
Total Cats: 225

You are awesome. Do you have a website with rates? Or how would one have a motor built by yourself?

I like what I see. I'm not in the market this year.. but next spring I might just be.
Fireindc is offline   Reply With Quote
Old 05-30-2012, 11:18 AM   #4
Senior Member
Thread Starter
iTrader: (1)
BogusSVO's Avatar
Join Date: Mar 2012
Location: Pensacola Fla.
Posts: 560
Total Cats: 185

Sorry, I do not have a website up (yet)

Check with your supporting vendors, thats why they are here!
BogusSVO is offline   Reply With Quote

Related Topics
Thread Thread Starter Forum Replies Last Post
Project Gemini - Turbo Civic on the Cheap Full_Tilt_Boogie Build Threads 52 08-28-2016 04:18 AM
Another Cast Manifold Corky Bell Prefabbed Turbo Kits 17 10-02-2015 09:28 PM
Bad head gasket or ? shooterschmidty Engine Performance 8 09-30-2015 10:28 PM
Another Alternator thread ihiryu General Miata Chat 9 09-28-2015 10:22 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 On
Pingbacks are On
Refbacks are On

All times are GMT -4. The time now is 04:20 PM.