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To port or not to port?

rickisrad

New member
I had to get a new set of heads (exhaust in coolant x2) and am debating whether or not to port these. I hand ported the last set and may have went too much on some areas and probably caused some flow inconsistencies. What power are the stock heads and intake good for?
 


Should ya? Why not? Though will you ever know if you are truly improving them? I think it's worth at least cleaning up the ugly seam and the short turn hump right above the valve seat. I put a lot of time in mine but it kinda sucks that I'll never really know if it helped or hurt. But, I enjoyed doing it and would do it again probably. One thing I'm gonna do since mine are off is rough up the intakes a bit. I made them pretty smooth, not knowing about fuel sticking to the walls. Since I'm on e85 it seems like an even better idea to keep the fuel mixed better.
 
Definitely roughen up that intake a bit. I was getting exhaust in the coolant and replaced the head gasket for a second time and decided that the gaskets looked good coming off. To get them pressure tested and magnafluxed was 200 dollars alone. I figure they are bad and bought a rebuilt set off Rock auto. I don’t think the lower intake could cause my symptoms so I will reuse the ported intake. I have a stock intake as well. I’m just not sure about porting the new heads if it is a negligible gain. I’m not pushing high power. Just the mods in my signature and I added Meth.
 
Gasket match and port the intake side, but do not polish.

Exhaust side you can remove all casting marks and smooth out the valve bowls. On exhaust runners Raise the ceiling a touch but do not exceed the height or the exhaust gasket. Make sure you leave the D shape in the exhaust runner though. Very important. Ive ported a dozen sets or so and guys have seen good results. Its not super hard to do, but it is pretty easy to do it wrong.
 


Gasket match and port the intake side, but do not polish.

Exhaust side you can remove all casting marks and smooth out the valve bowls. On exhaust runners Raise the ceiling a touch but do not exceed the height or the exhaust gasket. Make sure you leave the D shape in the exhaust runner though. Very important. Ive ported a dozen sets or so and guys have seen good results. Its not super hard to do, but it is pretty easy to do it wrong.


I ported my previous set and it looked ok. As for gains I don’t know. My concern with these is that the seats are already 3 angle machined and I don’t have money to do it again if I nick it.
 
i did a set too. many hrs spent yes rorking around the valve seats is kinda scary, dont start there, till you know how the bits act.

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If anything I may gasket match and do some light work. I don’t think I’m going to go nuts doing a full port. I’ll just pulley up to the 3.4 and put the 3.25 in the drawer. I may take it in and have the stainless valves lapped in and checked.
 
It's a waste of time unless you are going for records. You're looking at maybe a 10hp gain for the 20+ hours it takes to port them. By all means, do it if you want. But there are way better ways to pick up power than with porting heads.
 
It's a waste of time unless you are going for records. You're looking at maybe a 10hp gain for the 20+ hours it takes to port them. By all means, do it if you want. But there are way better ways to pick up power than with porting heads.

Been following your build. Can't wait to see some track times. Everything looking good?
 


Been following your build. Can't wait to see some track times. Everything looking good?

Yeah it's looking good so far. There's a lot I haven't posted yet because I wanted to do some testing on it first. I was thinking about maybe a patent on some of my work, but I don't think I really want to go down that road.

But it's looking promising. The blower is stupid loud at idle. Can't wait to hear it under boost. We should be going to the track Friday or Saturday with it and my buddy's turbo gp.
 
Thanks, that’s what I was contemplating. Whether the time vs gains are worth the time. I definitely do not have a track setup. Thanks for the help everyone.
 
It's a waste of time unless you are going for records. You're looking at maybe a 10hp gain for the 20+ hours it takes to port them. By all means, do it if you want. But there are way better ways to pick up power than with porting heads.

Question- I am switching over the 90# springs from the old heads to the new ones. My question is that I have ZZP stainless valves in the old one as well. Should I switch those over? I’m not sure how much of a difference if any the stainless valves would have over stock? Thanks
 


Question- I am switching over the 90# springs from the old heads to the new ones. My question is that I have ZZP stainless valves in the old one as well. Should I switch those over? I’m not sure how much of a difference if any the stainless valves would have over stock? Thanks

The stainless valves really won't make any difference. If they are oversized, they might help a very small amount. I would probably swap them, since you're taking the springs off anyways. But, it really won't make any difference either way.
 
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