Port and polish?

The ZZ intake does require having the stock intake thingy taken off. I don't know yet all that goes into it, but I do know that it's a pretty precise procedure. Our head jobs (at RayMac) start around 2500 and go up to just under 6000.

Here's what I do know:
You have to cut off the stock intake part to get a full port and polish on it.
Chris is VERY good at what he does, so you are getting what you pay for. This guy eats, sleeps, and breathes cylinder heads.
The horsepower gain is there in a RayMac head.
 
*nx* definately go with RAYMAC he does an excellent job.I picked up almost 200hp on having them do my head. I also had ZZ put on their manifold.
 
When decking the head a good machine shop will reseat the valves to compensate the material removed. If they do not reseat the valves deeper in the head, valve to piston clearance becomes a critical issue! If they do not reseat the valves, a thicker gasket in needed to correct the piston to valve clearance. If the deck of the block is decked, a thicker gasket will be needed to correct the same piston to valve clearance, plus piston to head clearance (squish)

Triston, if you want to meet up sometime at a pull, I will bring some cutaways for you to look at. If you decide to cut the intake off, I can help with that as well. We generally build our own, the others seem pretty pricey.
 
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So the million dollar question becomes What is the best application? Full blown motor? Is it worth it for a street truck? The only experience i have with a ported head was on a 12valve from a well known vendor about 4 years ago. The boards were full of people saying you will see and "easy 200 degrees drop in EGT" I cant say that much of a difference was noted, but I realise things have come a long way. The intake was not removed on that head, and admittedly, it is probably not fair to judge the head because too many changes were made at the same time. Besides if EGT goes down, that is just a license to add more fuel right.:evil Like posted earlier, I have heard on several threads that the only way to do a complete job on the cummins is to cut off the intake. If you are spending major bank on everything else for a competition vehicle, then it makes sense. If i am reading him correctly, Dually recomended doing some work on the bowls and leaving it be for a street truck. One of my concerns is that 24 valve heads tend to crack anyway, what would a full on port job do for that?? Obviously on a race vehicle, you probably dont care, but on a street truck that becomes an issue. Sorry for the long post, :blahblah1: but i have had many thoughts about this and hope somebody will chime in with some first hand experience
 
The 24 valve is pretty tough down inside the bowls. Cracks tend to be in the seat area, so porting does not remove material there unless cutting the seat for bigger valves. Just cleaning the bowls out on a 24 valve lets them breath alot better.
 
I do not recommend doing it if the head is on the truck and running good. If you pop a gasket and it is off anyway, then you may want to consider it. Head porting is one of those mods that costs a ton, but does not add much power for the money spent to do it.
A bowl job is as basic as it gets and will run over a grand by the time you get it all finished. Cutting the intake off and going in is where its at, but that is some big money for most except the dedicated competition rigs.
 
I knew I was askin for a how-to on split molecules but I thought it might teach me a thing or 2 and it has. Thanks all for the posts I'll keep watchin for pics and so forth and maybe get to see more of what Im lookin at when I tear into it in the future.

On a side note I was wondering what would you guys/gals that have blown head gaskets what other cost would be associated with this if I just keep pushin up on the one I got until it happens? Meaning what is the worst part of this? Tow bill? egos at the pull or track when it happens? or is there other head/block damage commonly takin place when they go? Im already gonna take my chances on the turbo unless I run into a pile of cash and I didnt know if I shouldnt with the HG and studs.
 
If you blow a hg the worst case is you might get water in a cylinder and hydrolock your engine. That can get ugly fast, especially if you are spinning it hard. If it blows between two cylinders and you keep running it you might wash out the head or the block, causing you to have to deck the block and/or resurface the head to get the new gasket to seal.
 
cnsmoke said:
*nx* definately go with RAYMAC he does an excellent job.I picked up almost 200hp on having them do my head. I also had ZZ put on their manifold.
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Would like to hear more about this, if you could/would share? What truck, how it was set-up and if the head was the only change? TIA
 
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