EA 3.9 head - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars
LinkBack Thread Tools Display Modes
post #1 of 7 (permalink) Old 11-13-02, 04:54 PM Thread Starter
Registered User
Join Date: Oct 2002
Location: Perth
Posts: 50
EA 3.9 head

Could anyone tell me if it is better to modify a 3.9 head or replace with an xr6 unit. Also, what is a good cam to install with an advanced + leaner chip.
I would like it to breath like a valiant 6.

Kevs EA is offline  
Sponsored Links
post #2 of 7 (permalink) Old 11-13-02, 05:29 PM
96 EF Futura
SiX_iN_a_RoW's Avatar
Join Date: Aug 2002
Location: Now Residing in Brisbane
Age: 33
Posts: 2,494
as far as I know the XR6 Head will give better performance in itself, however you could get a far bigger gain by spending the money on porting your current head and maybe fitting some bigger valves. If you do decide to go with the XR6 head spend a little money on portwork as the gains to be had are awesome...the XR6 cam is fairly mild but an improvement over stock nonetheless. However www.crowcams.com.au have some pretty good cams to choose from.

Lets go find that Hotdog tree I planted

Lowered EF Futura
Black Steelies ( too cheap to buy proper mags )
SiX_iN_a_RoW is offline  
post #3 of 7 (permalink) Old 11-13-02, 05:43 PM
EB wagon
Join Date: May 2002
Location: 8 Mile Plains, Brisbane
Posts: 932
Can someone explain the Porting process??? How its done, advantages, costs?


EB1 3.9L MPI Falcon Wagon with converted T5 / Pacemaker & 2.5" Redback sports exhaust / 2" lowered blocks at the rear, Kings lows up front / ED Tickford Head and Cam / K&N panel filter with XH intake Snorkel / Full EL Fairmont interior with woodgrain

89 EA1 3.9L TBI Falcon Sedan with 3 speed auto / currently being upgraded...
Brent79 is offline  
post #4 of 7 (permalink) Old 11-13-02, 05:51 PM Thread Starter
Registered User
Join Date: Oct 2002
Location: Perth
Posts: 50
Cheers S.i.a.R.
Kevs EA is offline  
post #5 of 7 (permalink) Old 11-13-02, 05:58 PM Thread Starter
Registered User
Join Date: Oct 2002
Location: Perth
Posts: 50
Brent, once I get mine sorted, I hope to be able to tell you.
Kevs EA is offline  
post #6 of 7 (permalink) Old 11-13-02, 06:22 PM
carazy's Avatar
Join Date: Jul 2002
Location: Adelaide,SA Australia
Age: 35
Posts: 1,966
Porting is simply drilling the ports (inlet and exhaust) in your head.
It's easy to do but very very hard to do right. There are alot of things to take into consideration when porting a head like the shape and lenght of the ports the compression chamber's shape and lots of flow dynamics.
normally porting involves simply enlarging the ports to match the inlet/exhaust manifold (match porting)
the next step is to simply enlarge the entire port which involves new bigger valves and normally make a big differance in performance (not so much with newer motors as they get better at doing it from the factory)
the final step is a lot of work and very expensive and normally involves totally changing the flow of the ports so that the bend at differant angles in the head. This basically involves designing a new head (and sometimes I swear it would be easier to simply cast a new one) and cost the big dollars but is normally left to professionals and race cars.
Polishing is a bone of contention and simply involves smoothing the port's flow to the valve. Some people think it's a great idea while others believe that the air doesn't tumble enough and there for you don't get as much atomisation of the fuel (aka good mixture in the chamber) It's differant for every head so you'll normally find that the people that do it will specialise and only do say old red 202 heads and maybe some 308 holden heads (these are easy to work with as theres a lot of metal to play with and the origional design leaves a lot to be desired.)
Advantages - better flow = more air and more fuel
- better exhaust flow
- differant noise (and it's normally quite tuff if you've got a good cam as well)
- heaps cheaper than investing in a 4 valve per cyl head
disadvantages - more fuel use (maybe not as much of a problem on efi I don't know)
- in some cases weaker heads (more likley to drop a valve)
costs can vary dude I was looking at 180 to shave my old XD head and about $500 to port it with new valves then another $400 for a cam. But it made a hell of a differance in my Cortina mate that thing was never a slug but after the engine work I could make a mokory of my mates worked Monaro. (no not the new ones it was an old 350 with extractors and a big set of carbs)

Breathe! It's only the internet....
carazy is offline  
post #7 of 7 (permalink) Old 11-14-02, 04:18 AM
Birth, Drift, Death...
Rollin's Avatar
Join Date: Jun 2002
Location: Drifting Brisbane...
Age: 34
Posts: 3,039
ahhh, to polish or not to polish, that is the question....

Slick, Quick and Fulliii SIK!!!
Proud TQE Operator

197.4hp at the wheels, 14.505@152.46km/h
Tuning in progress...
I can get new Genuine Holden/Ford/Audi/Land Rover/Honda parts cheap, PM me!
Rollin is offline  
Sponsored Links

  Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars > The Garage - Tech Forums > Engine Specific Tech > Inline 6 Tech

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Similar Threads
Thread Thread Starter Forum Replies Last Post
Another blown EA head gasket question ShaneP Inline 6 Tech 25 10-02-03 12:46 AM
EA head trauma! thomasEA5spd General Tech 4 02-24-03 12:04 AM
What about an AU block and head into an EA? carazy General Tech 5 09-19-02 05:35 PM
EA head bolts scooterscum Inline 6 Tech 4 08-11-02 04:25 PM

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

For the best viewing experience please update your browser to Google Chrome