q about new heads...

[jst6]

The little 289 in my car have the stock heads and I want to upgrade the heads ASAP. My biggest question is can I go with a 2.02/1.60 valve size and not hit the stock flat top piston? I don't want to be forced to buy new pistons to accommodate as that would mean an entire rebuild (one of those "while I’m doing this" type of things. Or would anyone suggest a 1.90/1.60 valve like the performer rpm head?

 

[LMan]

Id change your rear gears before I fooled with heads. You'll want a new cam then, anyway.

Rear gears, headers, carb, heads+cam.

 

[D.Hearne]

Another thing to watch for when head shopping ( for aluminum heads) is combustion chamber size. When swapping to aluminum, you want to increase the comp ratio, and all aftermarket aluminum heads have larger chambers than the 289's 54 cc heads. This will lower not raise the ratio. The smallest chambers offered for most heads is 58 cc. Which means you need to mill them to get them down to at least 54 cc for a 289. Most pistons have valve reliefs for up to 1.94/1.60 valves, very few accomodate 2.02's.You're better off anyway with the smaller valves on a 289.

 

[WantaGT]

here's a thought, a cheap one too. i'm having Thumper (just search Thumper in the 5.0 forums) port and polish my heads, intake, exhaust, bowls and milled to 50cc for $500 bucks. That might free up some money for gears and the such.

 

[65ShelbyClone]

I too would recommend 1.90/1.60 valves. Most mainstream aftermarket aluminum heads have a chamber around 60-61cc.

 

[coolblue65]

The only head that you can for sure get 2.02" intake valves with and have flat top pistons without worrying are Trick Flows.

 

[A67auto]

coolblue65, I checked out your site and it was cool, I also checked out your page where you installed the trick flow heads and noticed that you drilled the block, what was it that you were drilling and why? I have a set of trickflows that I am going to be putting on my motor pretty soon and I did not know you had to drill anything.. Thanks

 

[HistoricMustang]

I too would recommend 1.90/1.60 valves. Most mainstream aftermarket aluminum heads have a chamber around 60-61cc.

I am in the 1.90/1.60 boat also.

HistoricMustang
www.historicmustang.com

 

[coolblue65]

coolblue65, I checked out your site and it was cool, I also checked out your page where you installed the trick flow heads and noticed that you drilled the block, what was it that you were drilling and why? I have a set of trickflows that I am going to be putting on my motor pretty soon and I did not know you had to drill anything.. Thanks

It depends on what block you have, if you actually have the heads already, it is explained in the directions (I know who reads those ). Its basically necessary for the early blocks. The only way you will no for sure is when you pull your old heads off and if you see the 4 little holes there already, then you wont have to drill. If you have to, use the gasket to mark where to drill at-just get a couple of good drill bits and it will go quick.