Porting and Polishing

[Bobbo's F-350]

Has anyone ever port and polished there 7.3 or 6.9 heads or intake. I have talked to a couple of people who have done it to there cummins and they said it made a big difference in horsepower. I have not heard of anyone doing this to the 7.3 and the 6.9. I would like to send my heads and intake out to get it done. But I would like to talk to somebody whos has had it done. To see if there is really any big difference in horsepower and if it is worth the cost of having it done.

 

[suv7734]

Member "Icanfixall" will give yo the lowdown on that...

 

[FordGuy100]

I dont know if you will see all the much performance gain. Maybe a horsepower or two, but its nothing crazy. I would suspect that it would lower EGT's though, so you could throw in more fuel which would net you more power. For the cost of it, you will see hardly any power gain.

 

[RLDSL]

I was thinking about it while I had my heads apart but I got to looking at the open areas around the valves and the area of the existing ports and it looks like the factory engineers did their homework on these things. You might be able to open it up enough to get a little increase, but I doubt a whole lot.

I'd be Cautious about opening the things up, but polishing never hurt anything and it would impress the heck out of all those air molecules zipping by on the way through

 

[Bobbo's F-350]

I want to get the most horsepower I can out of my 7.3. But I would rather not spend all that money and not notice a difference.

 

[icanfixall]

Just do it.... I have done two sets of heads that are the new castings. They came from China and were really ruff in the port area. The first set were ruined when the motor burned down because the crooks at the machine shop installed the wrong freeze plugs without the proper tool. Plug pops out and coolant gone so no way for the sending unit to "see" coolant and the motor stops running on a grade. Cracked heads, burned pistons... No dyno run because I had 5400 miles on that motor. Now back up running but not enough time on the new motor for a dyno tun yet... Remember these motors are a large air pump. The quicker you get the air in and out the better it will produce horse power and lots of it. What I did was use the intake and exhaust manifold gaskets for a reason to port the intake, heads and exhaust manifolds. Its called port matching and it works. You really can't ruin the flow on these heads. They are not like a gas motor. We turn about 3400 rpm. Gas motors will turn 8000 rpm and up from there. A flow bench is required for them but not ours. We can polish the ports to a mirror finich because the fuel is injected almost directly into the cylinders and doesn't go theu the intake manifold. A gas motor can be cleaned up to a 300 grit finish. Any more and fuel will drop out and form droplets in the intake path. That will ruin the burn of gas in a motor. We can be differant. Really hogging out the ports isn't needed. The exhaust outlet port has plenty of extra material that can be removed for better flow. About $300.00 is about all it will cost to open up the ports for much better breathing of the motor. Horse power wise I can't say yet but I do feel plenty more over my other basic turbo motor I ran for over 270,000 or 370,000 miles. The motor in my signiture is running fine and the last mpg run with about 6000 in tow saw around 15.6 mpg doing 65 to 74 mph.... I do everything fast but one thing.....

 

[Bobbo's F-350]

I am surprised that it will only cost 300 bucks. I figured that it would cost well over that. For the heads, intake and exhaust manifolds. Well I will do it for that price. So any machine shop will port and polish them for me.

 

[Ironman03R]

Where in ohio are you? I've ported several sets of heads over the years and I'm doing a 6.9 build up, I'll be porting the heads in a month or so. I could do it for ya, or I can show you what needs to be done. You need to start with good heads though, no sence in porting heads with bad valve guides.

 

[icanfixall]

The exhaust port out of the head is where most of the material removal will happen. The intake side of the head has very little that needs to come off. The intake manifold is really close and its aluminum so it will be easy. The exhaust logs are easy. Particular attention needs to be paid to the drivers side exit port to the down pipe. For the trucks this is a really tight bend area where all that side of the motor exhaust has to squeeze thru. Keep in mind what you are trying to do is smooth out all the passages so the hot and cold air can flow easily thru everything. Smooth passages will speed up the flow way more than you think.

 

[riotwarrior]

... I do everything fast but one thing.....

Whats that.....tie your shoes

 

[icanfixall]

Don't tie shoes. Just wear slippers...;p

 

[Bobbo's F-350]

I live in Rome, Ohio. Its in Ashtabula county. That would be great if you could do that for me.

 

[Ironman03R]

Wow, I have no idea where that is. I'm near Findlay, shoot me a PM or an Email, I'm on AOL, same name as here.