Just curious, those that have had head work done, have any used this company?

http://www.extrudehone.com/

I used to read about it alot in the domestic magazines back in the day, just wondering if anyone here has used it.

 

13 years I did some extrude honing on a Q45 engine..........didn't improve things much as Japanese have used precision machining for years to squeeze out superior flow efficiency in their designs.

The $150 per HP rule applies to this proceedure...........the thing you do after spending $10,000 to gain the last 5-6 HP.

 

Some people tried it in porsche 928 intakes and got maybe 2hp at the wheels. Its not worth it.

 

Well then, I guess there's a reason I've never heard how much it cost...lol. Thanks for sharing fellas.

 

I did it on a b15 sentra intake manifold a couple years back. With a tune on mild boost on a 1.8L engine I saw an increase of almost 20whp and 25 ft-lbs.

 

I beg to differ. It is most definitely worth it.

 

It depends on how crappy the manifold is to start with. If its a good flowing design you will not see any gains.

 

again, this is not true. No matter what, there will be good gains to even better. All cast manifolds will have rough spots smoothed out by EH, aside from removing extra material to enlarge the runners which also gains power.

Just because a porsche 928 only got 2hp doesn't mean squat to me, I don't know what all was done to it or what motor was in it.

 

I've done this on the manifold of a Honda I had years ago. No gains. Results are going to vary by car. I would not recommend it on cylinder heads. I've heard nothing but negatives on the results for heads.

As for manifolds, its going to depend on where the restriction is. If the manifold already outflows the throttle body and heads, then there will be no gains. If the manifold flows less than your other parts, there will likely be gains.

 

That's more along the lines of what I've read about it. I would think it mostly depends on how porus the metal you're working with is to begin with. I could see an intake with long individual runners (alond the lines of tuned port) would have more of an increase than others, although I think heads of any kind would benefit the most. I don't know how much it would cost to do a set of heads, but from a time standpoint, I would imagine it's much quicker than the alternative. I'd like to see a VQ head flow comparo with this vs. traditional. I was asking because I see a short block in my future, and hell, if the heads were off...

 

We are going to be trying this on lower intake manifolds, and exhaust manifolds. For the relatively small cost involved, it certainly couldnt hurt. But I would not recommend doing cylinder heads with this method, IMHO.

 

I actually have a head from an old 4banger motor I had done sitting in my garage, and it's friggin beautiful. Makes porting and polishing look lousy in comparison, actually. and is a bit cheaper too!

 

No doubt, extruding looks VERY nice...but that does mean its doing anything for power. A properly flow benched and hand/CNC ported head is more of a fine art. Using an extruding machine is a bit more ballparking..if you ask me.