Blew the head gasket, finally, its a statistic. - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

old_mate · 08-04-2002, 02:31

Hey all

I had the pleasure of tracing a water leak on friday to find a whole shit load of dried coolant on the block. mmmm looked like welsch plugs. Take exhaust manifold off car and presto, head gasket blown.

No water in oil, steady loss of water, so due to the fact I have no other car I am still driving it. I hope mum and dad pick up their new car tomorrow, cos im shit scared about breaking head bolts and the like.

Ok, parts for me to do this are gunna cost me about $500 (new head bolts, gaskets, machining of the head, new exhaust valve seats and new brass welsch plugs.) I have been saving up a little for the supra box, but im thinking the box wont do much without a motor to run it.

Ok, now to the point. While the head is off the block, what mods do u guys suggest I do to it? (im not REALLY looking for a cam, unless I find a good one 2nd hand) im talking more about porting and the like. Can I clean up the head without modifying or changing the valves? I might also look at getting the EF intake while the top end is in bits. Bear in mind, Im also getting pacemaker extractors and new cats within the next month or two, so I would love my mods to complement each other.

I think thats all I wanted to ask. Any and every suggestion is welcome.

-Garth

peter_vod69 · 08-04-2002, 05:16

Oh boy, I had a head gasket let go on me when I was 800k from home at a mates place in brissie. What I got done was a reco job on my head, which included new stem seals, three-angle cutting the valves, and machining the face of the head a little, to bump up compression a tad., among other things. I would do this first as the devil, they say, is in the details.

With regards to porting, a couple of things. First, as with any breathing mod, you can do it without valve mods, but one helps the other. Also I have heard it is wise not to polish the ports to a mirror finish, as this can actually reduce air flow (sounds funny eh?). And apparently there is not much to be gained on the exhaust side of things, but every little helps...

Good luck with it tho, those heads sure are heavy buggers!

jamesk · 08-04-2002, 18:42

are you sure your exhust valve seats are rooted ? you should be looking at only a couple hundred bucks all up if you dont need them done

YOOT · 08-04-2002, 21:38

When th heads are machined, and the compression goes up does that mean you get more power?

jamesk · 08-04-2002, 22:06

technically. but you dont usually notice it a whole lot, if at all.

Bass Crazy · 08-05-2002, 00:41

From my experience, the exhaust side of the 3.9 head needs some serious attention. Have a chat to the guy who is going to be working on your head and he will suggest a few things. He should know what he is talking about.
The work will do will be determined by how much extra you want to spend, some guys charge an arm and a leg for custom head work.

I suggest you port match the head to the extractors. Also, rather then making the ports bigger, just get rid of any areas which restrict flow, these are sharp edges etc. The exhaust side is a bit of a mess IMO. Then get the comp bumped up a little, I have mine on around 9.5:1 and no problems to date.

You can then go on to remove the sworl in the head's combustion chamber. This will increase the flow ability of the head, but at the same time, drop down the comp, down to around 8:1 (stock is 8.8). To compensate this, you will need to deck the head even further, and use a thinner head gasket, AU gasket should do. With this comes an increased risk of blowing head gaskets.
This type of head work is more suited to being used with a big lift cam, and bigger valves.

Finally you will ask yourself, will I be better of simply bolting on an EF 4.0 or Tickford head instead of mucking around with the old 3.9?

Ciao

old_mate · 08-05-2002, 03:00

mmmmm interesting. I did consider going with a Tickford head, but i have been told I'd be better off with the 3.9. However, im thinking I have to get my head machined anyway, so if I start off with the better head, my efforts can only be rewarded fully.

bass, you reckon I will still need to match an xr6 head to my pacemakers?

cheers

Bass Crazy · 08-05-2002, 03:53

Honestly, I can't say for sure, however, I'm assuming, besides increasing the comp to get it back up to standard, you wont need to touch the sucker. Also, get the rocker's and cam with it... and you will have your self a noticable quicker car mate.

Rollin · 08-05-2002, 04:34

i would agree that polishing does not do much, but i reckon that a mild port job with particular attention to the valve area, to try and get the air to flow into the cylinder better, and also match port the intake manifold to the head would bring good benifits, especially when combined with a bigger cam

Bass Crazy · 08-05-2002, 04:51

Yer polishing is a waste of time in my book, unless you start hitting the 7000rpm mark..... u aint got that probel in an EA that's for sure.