426 head porting
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Topic: 426 head porting
Posted By: Peterson
Subject: 426 head porting
Date Posted: 26 Feb 2016 at 7:55am
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Ok guys, goin to start porting and polishing my 426 head soon. How far can a guy go in the ports? Any spots to watch for so I dont hit water? Any other suggestions would be great!! Thanks!!! ------------- 7095-685I at 255hp, 8070-225HP,8050-210Hp,8030 with 155HP,220 with 670T engine with A-pump, 7580, 185 with 140HP, 2-6080's,6070, S4 D17,wd45,CA,st34 agco, S1 D17 with 3500MK2 |
Replies:
Posted By: Big Orange
Date Posted: 27 Feb 2016 at 1:39am
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The area in the ports just behind the intake valve can be opened up & polished a little, but don't go crazy. Don't mess with the chamfer or the area around the valve on the head face, As that can mess up the swirl. polish the rest of the ports, intake & exhaust. installing rocker arms with a ratio of 1.75:1 will do a lot for the performance, plus some stronger valve springs & push rods. check the piston to valve clearance. for more low rpm, torque advance the cam, 3 or 4 degrees. GOOD LUCK |
Posted By: NEVER green
Date Posted: 28 Feb 2016 at 9:49am
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With respect Big Orange, I disagree on leaving the swirl notch on the intake face untouched. If you look on either side of notch there is a sharp edge of metal obstructing air flow, shrouding the valve, as designed only quarter of valve flows well. ------------- 2-8050 1-7080 6080 D-19 modelE & A 7040 R50 |
Posted By: NEVER green
Date Posted: 28 Feb 2016 at 10:39am
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Tyler, I purchased a head from from a guy named Max where he opened up the bowls above the intake valves, lots of material to remove and polished both ports. He also cut off the guides that protrude into ports. Took head to flow bench, intake hit 180 at 500 lift after that didnt gain, exhaust hit 200 at 550 and was still climbing. To me the intake port is too small and in the middle of port it narrows, a big no no. I have since opened up the ports middle and the roof making it taller and some what squaring it, never touched floor of the port, thats where the art of it comes in and need more research or leave it to expert. Didnt take back to flow bench but bolted head on and had gain in power fellow pullers and well traveled announcer noticed. Could try and post picture of ports if you like. ------------- 2-8050 1-7080 6080 D-19 modelE & A 7040 R50 |
Posted By: Peterson
Date Posted: 28 Feb 2016 at 11:21am
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Yes please post pictures!!!!! They always help!!!! ------------- 7095-685I at 255hp, 8070-225HP,8050-210Hp,8030 with 155HP,220 with 670T engine with A-pump, 7580, 185 with 140HP, 2-6080's,6070, S4 D17,wd45,CA,st34 agco, S1 D17 with 3500MK2 |
Posted By: NEVER green
Date Posted: 28 Feb 2016 at 12:28pm
Stock intake port ------------- 2-8050 1-7080 6080 D-19 modelE & A 7040 R50 |
Posted By: NEVER green
Date Posted: 28 Feb 2016 at 12:30pm
Not too harsh boys, this is my first head porting job, not exact same port. ------------- 2-8050 1-7080 6080 D-19 modelE & A 7040 R50 |
Posted By: NEVER green
Date Posted: 28 Feb 2016 at 1:25pm
Stupid shadow to left of port. ------------- 2-8050 1-7080 6080 D-19 modelE & A 7040 R50 |
NEVER green wrote:Posted By: Big Orange
Date Posted: 28 Feb 2016 at 5:51pm
| To much porting & polishing will increase volume of air flow & decrease the speed of the air at a lower flow rate. So that means it will increase the HP at higher RPMs & decrease the power or torque at lower RPMs. HP takes you down the track faster, but if you don't have the torque or power to finish the pull, you don't win. It takes a combination of HP & Torque to win. The speed the intake & exhaust valves open & close is very important, the easiest way to do this is install 1.75:1 rocker arms to replace the stock ones at a 1.48:1. alone with stronger valve springs & pushrods, advance the cam timing with a offset key, up to a max of 10 degrees. check the valve to piston clearance after you do this, retard the pump timing to about 25 degrees. Don't go crazy on RPMs, Pour the fuel & air to it & win some pulls!!!! GOOD LUCK |
Posted By: Peterson
Date Posted: 28 Feb 2016 at 6:19pm
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I have cut pistons already, so thats takin care of. Have a set of beehive springs already with retainers and locks to match. Need a set of pushrods yet. Planning on a set from Ed. Thanks for all the info guys! It really helps. And is REALLY APPRECIATED!!!! ------------- 7095-685I at 255hp, 8070-225HP,8050-210Hp,8030 with 155HP,220 with 670T engine with A-pump, 7580, 185 with 140HP, 2-6080's,6070, S4 D17,wd45,CA,st34 agco, S1 D17 with 3500MK2 |
Posted By: Big Orange
Date Posted: 28 Feb 2016 at 6:41pm
| Can Ed supply the rocker arms also? |
Posted By: Peterson
Date Posted: 28 Feb 2016 at 7:40pm
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Not sure. Was thinking perhaps kennys pulling parts. ------------- 7095-685I at 255hp, 8070-225HP,8050-210Hp,8030 with 155HP,220 with 670T engine with A-pump, 7580, 185 with 140HP, 2-6080's,6070, S4 D17,wd45,CA,st34 agco, S1 D17 with 3500MK2 |
Posted By: injpumpEd
Date Posted: 28 Feb 2016 at 7:57pm
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Rocker arms I bought are from Murphys. You can deal directly with them. ------------- 210 "too hot to farm" puller, part of the "insane pumpkin posse". Owner of Guenther Heritage Diesel, specializing in fuel injection systems on heritage era tractors. stock rebuilds to all out pullers! |
Posted By: KevinON
Date Posted: 18 Mar 2016 at 4:50pm
| What classes are you guys running with these heads?? |
Posted By: NEVER green
Date Posted: 23 Mar 2016 at 12:09pm
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Dont know about Tyler, I will be running in farm stock, basically too hot to farm. ------------- 2-8050 1-7080 6080 D-19 modelE & A 7040 R50 |
Posted By: farmtoybuilder
Date Posted: 23 Mar 2016 at 12:24pm
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Porting is Something I would let the Experts do! ------------- 5 different TT-10's,5 TT-18's Terra Tigers,B-10,2 B-207's,B-110,2 B-112's,HB-112,B-210,B-212,HB212,2 Scamp's & Homilite T-10. Still hunting NICE HB-112 & anything Terra Tiger & Trailers for them. |
Posted By: Peterson
Date Posted: 23 Mar 2016 at 3:21pm
Pretty much same here. ------------- 7095-685I at 255hp, 8070-225HP,8050-210Hp,8030 with 155HP,220 with 670T engine with A-pump, 7580, 185 with 140HP, 2-6080's,6070, S4 D17,wd45,CA,st34 agco, S1 D17 with 3500MK2 |