good heads to get me by?

-
cowboyup1107

cowboyup1107

Well-Known Member
Joined
Feb 28, 2011
Messages
79
Reaction score
4
Location
colorado springs, co
273 V8 number 2843675
on a .30 318 stock but want to build up til I can save up for a MP crate.
Are these heads going to really restrict any power gains? The build would include new pistons and rings thats it. maybe going .40 over.
very new to this so any and all info would be nice.
 
350ish the majority of my money would be going into a 8 3/4 rear end and a 3500 stall convertor for a 408 in febuary of 2013. i want to be able to drive the car spring and summer of 2012 and have allitle fun.
 
i also have a 360 out of a 85 truck that i can get my hands on for $250 that runs so i could always pull the heads of that to use.
 
It'll be pretty tough to get 350hp out of the 273 heads and they don't have hardened valve seats for unleaded gas. If it were mine, I'd use the 360 heads, mill them to try to re-gain some compression and be happy with 300-320hp while you build up the rest of the car. I'm planning a similar set up for an interim engine in my Duster.
 
a really good stock head is the 308 from an 89 or so 360 fuelie 40 hp gain never used them on a 318 but are awsome on a 340 but u need headers to take advantage of the high flow of the exhaust port oh ya before you buy used 308 check for cracks usally betweem the valves scince they are prone in this area good luck
 
All the posts above are good advice.

I believe that with some shopping and if you have the skills, you can build more power than a Mopar crate engine for less money. Just my 2 pennies.

If you do wanna buy a crate engine, look at the Blueprint 408 in Summit. It is in the area of $5k. That's a hard price to beat...
 
302 heads from a 85 to 87 318 ( look for the lean burn ignition mounted on the breather )
have the same closed chamber design as those 273 heads, handened seats, etc.
I would keep only the adjustable rocker assemblies from the 273 heads.
 
The 302 heads would probably be a better match.
 
cowboyup1107 said:
thank you all for all this advice. in order to tell they are 308 heads where would those casting numbers be on the donor heads?
Click to expand...

Pull the left valve cover and look on the number 1 intake runner
 
The local speed shop told me to build me a 414 stroker it would be $2181 for the stroker
valvetrain $2000 then intake carb and doug thorley try y headers would be $6181 for the motor build. then $450 for a convertor and $1700 for the 8 3/4 rear end. Thats the long term goal of this car but for now I am just looking to get it back on the road.
 
The 273 is a bit small for streetable and enjoyable HP at that level. Your much better off with the 360.
The head ID for 308 heads is located under the heads twin runners. (In the middle)

A nice combo for that approx HP out of a 360 would be something like;

Stock engine with a good dual plane, 650 cfm carb, a cam of approx 230 @ 050 duration and headers into a 2-1/2 exhaust. Depending on the 360 you get, some head milling may be in order to achieve about a 9 - 9.5-1 max ratio.
 
For the 273, use either the 302 heads ported, or milled down 1.88 360 heads, except measure what you had for chamber volume and then go another 2-4cc's smaller with the 360 heads...and of corse have a perf valve job on them..they should flow 215cfm or so.

the 302/675/920/178/315 heads will all flow the same give or take a few cfm, even ported, the open chamber versions may even flow a lil more.
Stock valve 318/273 heads flow 165'ish int/120exh cfm and when I port'em they go around 205/145 *with stock valves*fwiw
 
You must log in or register to reply here.
-

Back
Top