1998GsRIntegra

I picked up an OBD2 Jdm H23A Vtec motor with a PDE head yesterday from a local importer. I'm in the process of doing a full tear down on it. The block is going to be sent out for sleeving and I'm still debating as to weather or not I want to put 30+ hours into porting the head or just send it out. I was able to get all of the ancillary things removed today and with any luck I'll be able to pull the cams, remove the head, disassemble it, and disassemble the block this coming wednesday. My point in making this thread is to offer to answer any questions there still may be about this particular engine. I spent a good month looking into this specific engine and the info I found was in bits and pieces at best and not in any one place. So if anyone has a question about this engine or would like something measured, a picture of something, ect. please feel free to post up. I'd be happy to try to clear any fuzzy areas up. Don't be shy, I don't judge ...much

yungmulacrx

So does the pde head on the h23 have port work from the factory like the h22 euro r or type s?

1998GsRIntegra

Valve seats are blended into the head casting so there is no rough edge like with a standard b16 head, but beyond that, no additional port work.

ESP.net

PDE head same casting as Euro R/Type S as well as some OBD2 H22's. PDE has slight different valve angle. The casting does look smoother then some of the older P13 units, mainly noticable in the intake runners.

yungmulacrx

This is the picture of the intake ports on my pde head from a euro r.. Are all pde head castings like this or just type s euro r and h23a's?

bluehbcivic

I hade a PDE head on my H23 and there is NO hand porting/smooting or whatever

1998GsRIntegra

Valve seats are blended, runners are the same as anything else. Very similar to what Honda did with the B18c5 heads. Blending the valve seats smooth is worth roughly 10-15 cfm over leaving a lip where the seat is pressed into the head. I agree that the overall casting appears smoother out of the box that most honda heads I've seen. I think there's still a decent bit to gain in terms of flow with this head by working the chambers a bit and playing with the bowls. Shaving the intake guides down flush will usually get you 13-15 cfm and the short turn on the exhaust has a pretty substantial ridge as well that could be blended. I plan to spend some time on it so maybe I'll come up with something good.