coronan

More homework: http://www.ultimatesubaru.org/forum/topic/149443-improvised-exhaustmuffler-questions-1983-ea81-brat/ Quote from the above thread: Post 8 "What happens is that each bank of cylinders fires then the other. 1-3, 2-4.......so there is a full revolution where one side or the other is not firing. so the exhaust in each tube would slow to almost no flow during each "dead" rotation per side. " Does this justify the poor flow out of 3 and 4???? Is it by design???

Great article on port volumes and HP. http://www.hotrod.com/how-to/engine/hrdp-1012-ultimate-chevrolet-ls-cylinder-head-test/ Too Bad this guy never finished his project or posted about it. http://www.ultimatesubaru.org/forum/topic/79903-ea81-head-modifications/

Any updates? I was hoping to see how you balance flow. I build a home made flow bench and cylinders 3 and 4 flow only 75% of 1 and 2.

CYL 3 EXHAUST

I do not know valve lift for the EA81T. Nor EA81. It is not mentioned in the finley manuals. So ASSUMING A VALVE LIFT OF 0.400". A valve spends more time in the middle of its travel, so i am trying to build for 1/2 lift. 0.200. Its easy. As educational as this is, I don't want to spend all day measuring flows at 10 different increments per valve. Based on what i have read from other DIY port jobs and DIY flow benches: The flow increases linearly with valve lift and the gains from porting are linear. All of my flows will be at 0.2" valve lift measured on by the micrometer. Read em and weep. Stock Flow from an unported head. Intake Cyl 1 - 232 cfm Cyl 3 - 198 Cyl 2 - 253 Cyl 4 - 216 Exhaust Cyl 1 - 214 cfm Cyl 3 - 159 Cyl 2 - 216 Cyl 4 - 146 The low performers are NOT due to the S bend in the exhaust port on 1 and 2. The It is in 3 and 4. The bowl is big and beautiful. You can see the valve from the exhaust port. The problem is the port is damned near tear dropped shape. Reducing in cross sectional area as it approaches the end of the exhaust port. You almost need a borescope to see in there. Pics to follow.

Here is my flow bench. If I had to do this again i would make the box large enough to fit the head in side. I ran into some issues because the walls of the box limited the mounting locations of the studs. I am using 3/8 bolts to clamp the head to the box. It also holds the rocker shaft on. Instead of fabricating an elaborate arm to compress the valves I decided to use the rocker arms and a 3ft pry bar. The pry bar works great I can hold the valve steady with in 0.001". While i read the anemometer. I use some grease around the head gasket opening the aid sealing. When i started i noticed that the head would rock when i pried to open a valve. So i added 2 lag bolts to the intake side through the head bolt holes. The Vacuum is a Rigid 6.5HP running with no filter. The Pyle PMA90 Anemometer. $60 new from ebay. Has a function calibrate it to duct diameter. I'm running 3" PVC pipe with an ID of 3" Back when i used to measure emission on power plants we used a rule of thumb to find laminar flow but i've forgotten it. I believe it was "laminar flow occurs after 3 duct diameters in length after a transition" Can any physics guys confirm this??? My pvc pipe is 36" long. There is 16" of straight pipe before and after the anemometer. Thats 5.3 Duct Diameters. I used a hole saw to cut the opening for the anemometer I placed the core back in to the tube to help fill the gap and leave the walls as smooth as i could to not cause turbulence around the sensor. The system flows a maximum 415 cfm without a head on the box. Pulls almost 1.5" Hg of vacuum with a head on and valves shut. Intake valve open Vacuum level is about 1/2" hg Exhaust valve open vacuum level is about 3/4" hg Each time i mount a head I note how much the system flows with valves closed and subtract that from the flow reading with the valve open. The system usually leaks about 20 cfm.

i was hoping for lift. i saw 36mm cam diameter. Not sure if that is with or with out the lobe. If i knew lobe height and cross section diameter we could figure it out. The Rocker is probably 2:1. No one has a cam laying around?

I read the finley manual. Valve lift is not in there.

can anyone tell me specs for the stock ea81t cam shaft?

Thanks Carfreak! This is what I consider a "while your in there mod" . I am going to focus on flow balancing the cylinders so the fuel ratios is the same. My time is free. The crude flow bench I am building is going cost less then $100. Can anyone tell me what valve lift is on the EA81T stock cam???

I'm tempted to get rid of it. Technically the cylinders only fill one at a time.

Being that my thread title is no longer appropriate; I am Moving this to a new thread. http://www.ultimatesubaru.org/forum/topic/151762-porting-an-ea81t/

Phase 1 remove flash, Unshroud intake, blend around valve guide. 60 grit How am I doing? Stay tuned: flow bench build is next.

Searching does not yield much for this motor let alone pictures. So I'm going in blind. Maybe I can get some feed back. Or Someone Can learn from my mistakes. What is this ridge about??? Any recommended areas to clean up? Port is already matched to the gasket. Actually the gasket is slightly smaller stock. This head would actually be a great candidate for extrude honing, But thats def out of the budget. Questions... The casting does not have too much flash. Remove all of this valve shrouding? Raise the roof? Remove most of port divider? Shave inside corner? Raise the roof or just polish?

Searching does not yield much for this motor let alone pictures. So I'm going in blind. Maybe I can get some feed back. Or Someone Can learn from my mistakes. What is this ridge about??? Any recommended areas to clean up? Port is already matched to the gasket. Actually the gasket is slightly smaller stock. This head would actually be a great candidate for extrude honing, But thats def out of the budget. Questions... The casting does not have too much flash. Remove all of this valve shrouding? Raise the roof? Remove most of port divider? Shave inside corner? Raise the roof or just polish? Phase 1 remove flash, Unshroud intake, blend around valve guide. 60 grit [sharedmedia=gallery:images: How am I doing? Stay tuned: flow bench build is next.

Phase 1 remove flash, Unshroud intake, blend around valve guide. 60 grit

Port and polish questions: The casting does not have too much flash. Remove all of this valve shrouding? Raise the roof? Remove most of port divider? Shave inside corner? Raise the roof or just polish?

Plenty of room. Passenger side is the hardest. The head studs want to scratch the combustion chamber. I want to do some porting and polishing. I'm having poor search results with images. What is this ridge about??? Any recommended areas to clean up?

Thanks for the note on flipping the intake. It inspired confidence. I believe the head can be dropped out with out touching the motor mounts. (at least on the passenger side). Unfortunately one of the intake manifold bolts broke. Ill post pics this weekend. My local engine builder wants to "extrude hone" the head ports. Anyone heard of this??? Some kind of sand blast port and polish method, i think?

Hello, I'm pulling the heads this week. I have a few questions. I understand it can be done in the car. I found the access holes for the rocker shaft bolts last night. 1. Can it be done with the intake manifold in place? (This would be amazing given that i have AC, and Turbo MPFI plumbing) It looks like it could be dropped down and slid to the back. 2. Anyone have a good vacuum hose diagram for this? Turbo EA81 seems to be less documented. 3. Does the block need to be checked for flatness / sanded? 4. Should hydraulic lifters be cleaned / replaced? (I do not have any lifter tick at the moment) Running synthetic 10-40 oil. 5. How do i get the push rods lined up in the lifter during reassembly?? Thanks!!!

http://jalopnik.com/who-keeps-stealing-all-the-old-subarus-in-portland-1680960576

Has anyone figured how to make the side windows flip open on the brat toppers? Contractor Style? Pics of the conversion? Thanks!!!!

I have had success returning to rock auto. I think they paid the shipping too. I just called and said part was not as described.

Wholesaler closeouts for your 1988 SUBARU GL: http://www.rockauto.com/RSS/vehiclefeeds.php?carcode=1268535&m=wc&l=en&html=true Wholesaler closeouts for your 1982 SUBARU BRAT: http://www.rockauto.com/RSS/vehiclefeeds.php?carcode=1267679&m=wc&l=en&html=true Wholesaler closeouts for your 1984 SUBARU BRAT: http://www.rockauto.com/RSS/vehiclefeeds.php?carcode=1267736&m=wc&l=en&html=true Enjoy.

Your getting your stainless too hot. I'll bet its sugared through on the inside. Try using silicon bronze filler.