GK head on RD block, what's involved?
06-28-2016, 10:44 AM
#12
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Vehicle: 2000/Hyundai/Coupe F2 Evo
measured the inlet ports on the gk head the other day, they are 9mm wider and 5mm taller than the rd ports, the throat section is also a lot more open than the rd head so this will explain the differences seen on the flow bench. Had a look at my brothers gk inlet manifold and the runners are a fair bit shorter (but obviously wider) than on the rd's. I've been told the longer runners will allow a better/faster air flow so coupled with the big ports on the gk head a little gain should be seen. Fluid dynamics isn't exactly in my vocab so just passing on what i've been told. You guys have been playing with these far longer than me so would be interested to hear your thoughts.
Intake cam from Elantra, exhaust manifold from Elantra...now cylinder head from Elantra 
07-30-2016, 01:35 PM
#18
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Vehicle: 97' Hyundai Coupe
Found 2002 Elantra 2.0 and mondey will buy the head. 9mm wider and 5mm taller is big difference ! My ITBs are 50mm to 44mm and I might also buy the IM from the same Elantra. The bad thing is that I have to cut it again and make everything work, but if its really that big of a difference I'll do it 
10-10-2016, 08:49 AM
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Vehicle: 2000/Hyundai/Coupe F2 Evo
my head swap was completed a little while back complete with RD exhaust cam converted to run on intake side, also an RD exhaust cam for the exhaust.
Gained around 9hp although it was still rising when it ran out of revs, also gained around 12nm torque.
Dyno 08-10-16.jpg
Gained around 9hp although it was still rising when it ran out of revs, also gained around 12nm torque.
Dyno 08-10-16.jpg
10-10-2016, 03:55 PM
#20
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Can you post the before graph? Driving impressions?
Hopefully I'll finish putting my car back together tomorrow. I did a full rebuild + 1.8 pistons + P&P Beta 2 head, shaved ~30 thousandths. Before it made 132whp 130tq on a Dynojet. Hopefully the whp will be in the 140's now. It should be one of the quicker NA J2's.
Hopefully I'll finish putting my car back together tomorrow. I did a full rebuild + 1.8 pistons + P&P Beta 2 head, shaved ~30 thousandths. Before it made 132whp 130tq on a Dynojet. Hopefully the whp will be in the 140's now. It should be one of the quicker NA J2's.