Dakota Durango Forum banner
1 - 20 of 104 Posts

· Registered
Joined
·
708 Posts
Discussion Starter · #1 ·
Now, I know everyone on here just hates stock heads and your gonna tell me to go buy Eq's for 900 dollars. Im not trying to spend an arm and a leg here.

So, if I find a nice set of stock heads that aren't cracked what kind of gains am I looking at with port work? Saw an article in mopar magazine where they did stock 360 heads and got almost 60 horse on an engine dyno.

Pros? Cons?

Tips? Things to look out for?
 

· Dakota for Life!
Joined
·
1,961 Posts
I've done some backyard porting myself. I dont have any before/after hp gains, but I'm certain they're better than stock. On most any head, a good gain will be had by doing some bowl (just under the valve seats) blending. Some may call those "valve throats". Anyway, you can see my before/after pics. All I did was blend the factory machine cut into the cast port wall. You can see what I'm talking about in the first pic. See the intake side at about 11:00 o'clock how it's sharp and protruding into the port. Then see how I blended it in the second pic. Blend all your intake/exhaust ports like that and you'll see some gains. BTW, unless you're going all out racing, no need to make the ports/runners/chambers look like a mirror. Also, I found it beneficial to take a drop light and have it shine thru the port so I could see what I'm doing better. Good luck and be certain not to nick the valve seat.




 

· Registered
Joined
·
708 Posts
Discussion Starter · #3 ·
Thanks for the info, an old drag racer at work got me thinking about this whole thing and he showed me on a set of heads all the stuff I need to smooth, blend ECT. I guess im trying to figure out if its worth all the work of porting and swapping the heads to another stock ported set.

Were your gains considerable?
 

· Dakota for Life!
Joined
·
1,961 Posts
I couldn't tell you gains from the heads alone. When I bolted on the ported heads, I also install an M1, cam and headers. I can tell you this, that little 5.2 motor turned into a beast after those mods.
 

· Registered
Joined
·
1,305 Posts
truth be told,the factory heads are pretty good.when compared to 60's-70's engines,these heads would have been tops in the aftermarket.i'm sure they will take a porting/polishing very well.NOW,if they decide to crack,then don't say i didn't tell you so.
 

· Registered
Joined
·
623 Posts
A little port work will definitely help the stock heads. Clean up the bowls and ports of casting flash and irregularities and be sure not to knick the seats. I wouldn't bother polishing. You might even find some Mopar porting templates on Ebay.
 

· keep your stick onthe ice
Joined
·
965 Posts
I haven't done it yet I've been looking at a set and I agree with there are gains to be had in the bowl area. The runners look pretty thin to start with and I'd be a little afraid to take much if any out of the intake runners maybe a little on the exhaust but that's a short runner anyway.
 

· Registered
Joined
·
1,075 Posts
I know this is spending money, but go get a good Serdi/Sunnen valve job which will do all the cutting under the valve (which is the most critical area) for you. All you will have to do is blend it afterwards. It will cost about $300 but will save you about 6 hours worth of work!
 

· Registered
Joined
·
708 Posts
Discussion Starter · #14 ·
I was going too. I figure they were on the truck, ran and didn't leak before. Out of sight out of mind

... I know thats really not the right way to look at things but I'm going for on the cheap
 

· Registered
Joined
·
708 Posts
Discussion Starter · #15 ·
Well I had a date with a flow bench today. @ .500 lift the exhaust and intake are both flowing 20 more cfm then stock

I don't know how some people are getting 270 out of these things.. The guy running the flow bench said that the valve job will help alot but I can't see it gaining 50 more cfm haha
 
1 - 20 of 104 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top