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Need advice! head porting tips

OrangeL67

OrangeL67

New member
So I have my heads being ported out by Randy Hilbrand in Michigan. After talking to a lot of folks in various car clubs, it seems this man knows his stuff and is very talented. His style of porting a forced induction engine seems to be based on velocity. He has an impressive private machine shop, and dyno numbers from lots of cars showing 30-60 crank horse gains from his headwork alone.

Right now he is doing his base p&p that he believes will net some pretty good horses. I'm also changing out the stock l67 valves for the larger l32 valves, and milling the guides to accept 600 lift.

Anyways, he says the bulk of where power will be made is in the valve chamber area. (Between the exhaust & intake runners.) I originally wanted to port match the intake side, but he thinks it will not net much gains being that the engine is forced induction. He actually thinks I'd make more power with my cam by just smoothing the runners, slightly opening them up, and slightly manipulating the flow characteristics because "the air is going to get in and out without problems ".

He says bowl work (polishing) looks pretty, but it wont be worth the labor. Any opinions? I ask because I can pay him to do these things, but I'd hate for it to be a waste of money. Thanks.
 
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Well that was easy lol.

Why does every vendor match their heads and Polish the bowls? You'd think they would just do the basics and sell more heads cheaper.
I guess I will just let the man do what he knows.
 
exhaust is more important than intake for gains. the polished bowls are meh at best, i wouldnt even care to have that done.
 
The trick on the intake side is to rough it up, because you want correct atomization of the air...not sure smooth, because then it just glides by. You do however want that on the exhaust side...smooth as glass is key as well as keeping the stock "D" shaped exhaust ports.
 
bluegtp91 said:
The trick on the intake side is to rough it up, because you want correct atomization of the air...not sure smooth, because then it just glides by. You do however want that on the exhaust side...smooth as glass is key as well as keeping the stock "D" shaped exhaust ports.
Click to expand...

In the heads yes, lim no.
 




Hell, now I'm confused lol. Is the bowl the important part, or the area where the valve stems run? He says it's the valve stem area where power is gained.
 
the bowls are what the valve sits in. porting and polishing those youll see some good gains.

polishing the combustion chambers is what you want to not car about.
 
Very well gentlemen. I appreciate the input. I just gave him a call to have the bowls blended and polished. I will have pics of the heads up in a week or so.
 
^Me too lol.

The heads are done. I'm picking them up Wednesday. I've got the runners done, intake runners opened up, but not matched. Exhaust. Side polished and opened, bowls swirl polished and blended. Competition valve job for slightly larger valves, and the valve chambers ported/ polished. This should amount to essentialy a stage 3~port job more less. Oh and for only $450. Maybe if I pick up some good power, you michiganders will have a reputable head porting source for on budget builds.

I will post pics and dyno results after recent mods including Gen v, heads, and possibly 1.7 rr's. (Appointment is April 15)
 


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I ended up going all out with them. These came out looking good IMO. We will see what type of power they produce
 
dsmuts said:
How much did that cost and what all is done to them?
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L32 valve swap, viton valve seals, very nice 3 angle valve job, blended & polished bowls & combustion chambers, back cut valves, P&P intake runners, P&P exhaust runners, clearanced to accept 600 lift, rounded & polished short turn radius on intake and exhaust.

We DID NOT quite match the intake runners, but he opened them up quite a bit. He said it wouldn't be wise to gasket match the intake side without opening up the full length of the intake runner ($200 more in labor) and even then, it would not yeild much power if any at all due to forced induction.

Cannot say how much I paid bc to be honest, I got a great deal and I plan to make a profit off of these one day. How much?.. will depend on dyno results
 
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