ported and polished heads on an idi?

[J-ROD Diesel]

Hello guys! My name is Jared and im kinda new here. I have a 1992 F-250 7.3l idi and was just curious if you guys have ever heard of an idi with ported and polished heads? I have heard that scince our engines turn such low RPMs that porting and polishing doesnt really help out that much on the power side. Whats your opinions on this? Has anyone done it and can say that it was worth doing? I apriciate it guys im just getting ideas for the wish list!

 

[redneckaggie]

I believe there was a thread a while back where someone got stock heads on a flow bench and did a little grinding to see how much it helped out

 

[racer30]

IMO The cylinder heads flow pretty good for what they are. But there are some places to make some improvement. If you havent seen a IDI head before I will try to give you some Info...The valve seat is installed in the head and there is some casting edges that the MFG dosen't clean up. Doing some grinding just under the valve seat into the port to remove the edge will help flow. The ports have some ruff spots in the casting that cam be smoothed out as well. Doing a good 3 angle valve job will help too. The valve timing and lift is the big problem IMO. The valves only open .380" and the cam profile is for a NA engine and has to much overlap that makes the engine just a bit inefficient when running a turbo. There are a few reground cam profiles that help this be more turbo friendly. If your looking for more power You need to start by getting some gauges to keep a eye on the exhaust temps, oil pressure, and boost if you want to put a turbo on it. Then look into a performance IP and injectors. All the info you need is on the forums somewhere you just need to find it.

 

[J-ROD Diesel]

Thank you for the info guys! ill see what i can find in the some 32,000 threads on the idis haha

 

[TahoeTom]

Look up Barnett High Performance in Laingsburg Michigan. He does porting and polishing on heads including ours. I talked to him and he said the most gains were on non turbo applications because of improved flow. With a turbo the flow is forced and the gains would be less.

 

[J-ROD Diesel]

i had actually looked there and thats a great website! thank you!

 

[91idi]

I ported and polished my 86's heads. I also did other mods so who knows how much was from the pp. But I do know my 86 is making good power

 

[J-ROD Diesel]

Do you have a turbo?

 

[hesutton]

Gary (icanfixall) has ported and polished the heads on his IDI. He'll be along here shortly to share his knowledge on the subject.

Or...... search for it here..... he's posted it many times.

Heath

 

[icanfixall]

Thanks for the intro Heath... Porting these heads can't hurt them be it na or turboed. Much of the gains will come from the exhaust port. As the flow goes past the seat it has to make a tight turn. That curve needs to be smoothed out some towards the coolant jacket side. The top of that exhaust port has no cooling around it and is around 3/8 inch thick. Thats the bump you see looking at the head as it sits on the engine. As posted above. The factory did a good job but flash is generally left behind restricting flow... Think of this like fingers dragging thru the water. It slows down the flow and distrubes the flow... Same thing happens with air or a gas flow. Its true that we are not spinning these engine at high rpm so not much going on in our ports.. But cleaning up the mess left behind from the manufatureing is a good idea. Also we can polish the ports without the problem carbed engines have.. We only suvk in air.. No fuel is mixed in the air charge like a gasser engine has. We wont get fuel drop out on the ports either because of this differant idea. We suck in an air charge and then inject fuel into that. Both of our valve springs are the same item. Not like in a gasser where they are differant springs with differnt lb ratings. Now think about a port or tube that has some fingers of metal on the walls. Now compress the air just on the intake side of the intake valve to 15 lbs. Open the valve and let that air pressure enter the cylinder. Now smooth out those walls with all the problem fingers distrubing the air flow at the same pressure.. You tell me which port is going to flow more air. I have tried to explain what and how it looks to me but you may have a diffrant thought too... There is no right or wrong answer to porting. I run a stock Banks wastegated turbo on a stock intake with a stock cam. I ported my heads. I'm able to cruise at 85mph doing 1850 rpm getting 18.9 mpg. My hands are thought to be magical but they are just the items I use to scratch myself.....

 

[Ford420ci6point9]

Thanks for the intro Heath... Porting these heads can't hurt them be it na or turboed. Much of the gains will come from the exhaust port. As the flow goes past the seat it has to make a tight turn. That curve needs to be smoothed out some towards the coolant jacket side. The top of that exhaust port has no cooling around it and is around 3/8 inch thick. Thats the bump you see looking at the head as it sits on the engine. As posted above. The factory did a good job but flash is generally left behind restricting flow... Think of this like fingers dragging thru the water. It slows down the flow and distrubes the flow... Same thing happens with air or a gas flow. Its true that we are not spinning these engine at high rpm so not much going on in our ports.. But cleaning up the mess left behind from the manufatureing is a good idea. Also we can polish the ports without the problem carbed engines have.. We only suvk in air.. No fuel is mixed in the air charge like a gasser engine has. We wont get fuel drop out on the ports either because of this differant idea. We suck in an air charge and then inject fuel into that. Both of our valve springs are the same item. Not like in a gasser where they are differant springs with differnt lb ratings. Now think about a port or tube that has some fingers of metal on the walls. Now compress the air just on the intake side of the intake valve to 15 lbs. Open the valve and let that air pressure enter the cylinder. Now smooth out those walls with all the problem fingers distrubing the air flow at the same pressure.. You tell me which port is going to flow more air. I have tried to explain what and how it looks to me but you may have a diffrant thought too... There is no right or wrong answer to porting. I run a stock Banks wastegated turbo on a stock intake with a stock cam. I ported my heads. I'm able to cruise at 85mph doing 1850 rpm getting 18.9 mpg. My hands are thought to be magical but they are just the items I use to scratch myself.....

YOu have an overdrive right? My '87 6.9 "cruises" at 3300 at 65mph I've got the c6 with 4.10's

 

[hesutton]

YOu have an overdrive right? My '87 6.9 "cruises" at 3300 at 65mph I've got the c6 with 4.10's

Gary has double OD really. The E4OD with a Gear Vendor OD unit behind it. Dude can cruise crazy fast and very fuel efficient RPM.

Heath

 

[Ford420ci6point9]

Gary has double OD really. The E4OD with a Gear Vendor OD unit behind it. Dude can cruise crazy fast and very fuel efficient RPM.

Heath

I see, I was surprised when he said that, my top speed on flat ground is about 71 foot to the friggin floor.

 

[Thewespaul]

I see, I was surprised when he said that, my top speed on flat ground is about 71 foot to the friggin floor.

You must be registered for see images attach

 

[DrCharles]

Engine temp and oil pressure look kinda low to be flogging it like that, Wes