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Nope, 4v valves in a 2v head means you cannot get the short turn right without hitting water.RWadley wrote: ↑Mon Nov 16, 2020 4:44 am Australian Clevo heads are closed and open chamber with 4 V and 2 V ports.
We have found that lowering the exhaust port to obtain a straight outlet, boring the intake runners, inserting ssteel valve stems and using 4 V valves gives a head with capacity to create 600 hp on a good bottom end.
Once again the Ford GT had the big heads in cars capable of 160mph in 1973
1973 XA GT RPO 83 hardtop Ford Falcon
WOW.............talk about pushrod "X" factor.......lol...........never seen that before.......cool pics.
Yes ive tried the 2.19 valve seat trick on 2v head but it doesn’t work. Hit water. These seats we use in the stock elim trick are considerably wider mind you.KnightEngines wrote: ↑Mon Nov 16, 2020 6:19 am Aussie 2v clevo head with a 2.055" valve & 50 deg seat, r&d project.
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Looks good. That should pick them up a fair bit. Are you going to flow or run as is. The area you did is the most critical. There’s a bit in short turn but its touchy like i said. I would flow first then grind a bit and check again going little bits at a time. The guy whose bench i use has done about 10 sets (for me alone)he knows exactly how much to cut there. I used to do them by the eye but let him now with bench. Hes better at it than i am( does porting for a living). The port can be straightened out a bit to if you wanna go that far.cgarb wrote: ↑Thu Nov 19, 2020 11:36 pm image000000_01.jpg
This is what I have done with the porting. No valve seat work yet, waiting on the valves. I used a valve seal cutter to trim the guide bosses down to .531 as far as I could and then used the ball carbide to blend as far as I could. I blended the chamber and polished it up a little with a stone. I removed as much material as I could from the chamber wall around the exhaust valve without getting into the head gasket sealing area. Took out the lips and edges mainly and rounded the short turn over to get a smooth radius and not a sharp edge. No other work in the intake or exhaust port, just the bowl area.
If anyone has any interest, here is the engine with the filled heads. We just ran it last week.. Specs are 347 10.5 to 1 Pump gas, Hydraulic single pattern roller with solid lifters set at .010 Lash 250@.050 109LC .650 Lift in at 106 Factory intake manifold.Kenny M wrote: ↑Mon Nov 09, 2020 11:43 pm plate.pngLike Steve K said.. They really don't need much. I just built a 383 with very mild head clean up work and with 12to1 and a cam that is 260 at .050 it make 625HP. 585 with the stock intake manifold. These heads flowed 325 non touched port with bowl clean up.
I did test a set of the MPG brass EX. tong's a while back and saw nothing , on a 525HP 347.
I will be on the Dyno on the 10th of this month with a 347 Boss 302 . these heads flowed amazing they must of started as a very good core with just a bowl clean up and a good valve job nice .080 wide bottom cut they flowed 337 airspeed was 260. being it is a smaller engine, i installed the aluminum Parker port stuffers, i feel that these are the best.. It did loose some air flow at .500 it went from 300 to 290 and at .650 from 337 to 320 but air speed picked up to 300 ft/sec.. With some PR pinch work and cutting down the port plate on the PR side floor, i did get the flow back and kept the air speed at 300. My port stuffer ended up looking alot like Steves picture of the epoxyed port.