Porting to reach high rpm breathing

Magnus

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The old "unshroud the valves" porting while leaving the rest of the runners largely intact is really removing material to create a constant cross sectional area all the way to the valve seat. Consistency of flow and consistency of surface area and surface finish are the biggest determiner of boundary layer behavior and ultimately fluid resistance to flow (pumping losses)
 

Magnus

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Who let killer bee in here? Lmao




Jk carry on interesting stuff!!!

Hahaha on that note let me reiterate that everyone encouraging this thread is trying to reach unfound heights of dmax performance by optimizing the engines biggest strong point. I've had a few beers but I can still do enough mental math to realize these mods aren't cost effective for 99.99% of the dmax community.

But carry on.
 

blk smoke lb7

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Hahaha on that note let me reiterate that everyone encouraging this thread is trying to reach unfound heights of dmax performance by optimizing the engines biggest strong point. I've had a few beers but I can still do enough mental math to realize these mods aren't cost effective for 99.99% of the dmax community.

But carry on.
This may be true ( a larger turbo is a quick fix) but I am enjoying lower drive pressures faster and more flow for the same turbos on another truck along with lowered egts so it was worth it to me and if I learn from this thread......even better. Not trying to start anything , just a fan of porting is all.
 

x MadMAX DIESEL

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Could you feel a seat of paints difference when you did yours? I'm guessing prolly not as I'm sure you went with a bigger charger the same time. Jw about if anyone's actually done just heads alone and could actually tell a difference
 

blk smoke lb7

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Could you feel a seat of paints difference when you did yours? I'm guessing prolly not as I'm sure you went with a bigger charger the same time. Jw about if anyone's actually done just heads alone and could actually tell a difference
I built my motr and did the heads at the same time then threw the stock turbo on till I could figure out what turbo and or what kit to go with,if anything I hurt myself,cut the compression and opened everything up,i had a small charger trying to put air into a big ballon.Then I got the 366 and it was a blast and the truck ran great so I cant really say, I know its night and day on a gasser but that's non turbo.

I can tell you a good friend of mine bought an 02 with a 6 inch lift and 37 inch Baja claws.The headgaskets went and I talked him into porting nothing else was added,he got 13 mpg and could run his edge hot juice on full with not problems anfter fresh ported heads,c gaskets and arps 16.5 mpg and the truck would limp on on lvl 5 and 6.1 other thing is it made the truck extremely responsive.I have no before and after dyno result or 1/4 mile times,just my ass dyno but the truck moved out after that and nothing else was done to it.
 

Magnus

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I'm not saying there aren't benefits to be had, I'm just saying if the heads are still bolted to your engine you'd have to have some other pretty serious mods done before it's worthwhile to remove the heads for this sort of work.

I don't want to discourage the sharing of knowledge, just throwing a disclaimer on here so nobody thinks they can take a dremel to their aluminum and suddenly blow away all their wildest dreams on a stock turbo. I think the internet misleads people most often because they read what they want to read instead of seeing reality.
 

Fahlin Racing

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No harm done, your thoughts are good to the topic Magnus. I like your thinking. We must view flow from where the air charge unloads into the intake manifolds and then through to the chambers.

From my picture of one of the intake bowls there, that bowl forms a terrible venturi shape. I would like to see a CFD on it,maybe its what I think is happening or it may be something else. If you look at each bowl, you will notice the Dmax heads have different short side radius heights between both intakes and exhausts making it a totally different ball game for each runner.
 

jkholder09

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Fahlin Racing if you are really looking to get some good flow you need more meat in the casting.
Get with Mark Broviak on here and buy a set of Brodax heads I bet you may find the answer you are looking for.
 

Fahlin Racing

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Yeah, I've seen those floating around somewhere, it would be an interesting looker. I spoke to Lorenzo @ Socal today and he told me quite a price on a set of those. I understand and have read the stockers are thin in some areas which always is a pain.

After having more time to read the rest of the posts recently. Magnus makes some great points, albeit, where are you speaking of turbulence Magnus? post valve seat? If you imagine the runner approaching the SSR, the moving down to the venturi area. How much time and area do you think you need to produce the proper flow past the intake valve? I think there may be a possible turbulence problem near the seat around the width of the SSR, if not, thats awsome since it should something different. Wet flow will tell. Like I said before a CFD on these heads would be very benefical!

If you don't have a certain time that the air flow can straighten enough to change directions without producing separation around the valve head we usually see a 'break in the flow-cone' as old Smokey would say and flow would be limited, plateau or go down possibly. Being that we can lose CFM just by a seat angle width change, I believe all portions are needed to be observed.

Has anyone thought about adding material anywhere? Granted these heads are not the largest ports in the first place.

I suppose this information should be stated, per square inch of area only 146cfm of flow @ 28" of water (maximum).
 
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jkholder09

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Yeah, I've seen those floating around somewhere, it would be an interesting looker. I spoke to Lorenzo @ Socal today and he told me quite a price on a set of those. I understand and have read the stockers are thin in some areas

Has anyone thought about adding material anywhere? Granted these heads are not the largest ports in the first place.

.

Yes jeremy wagler and brodax.
Just spend the money
You will be less into them and they flow 300 cfm unported.
I bet 400 cfm with a good port job.
That 3000 crank hp worth of air
Schied billet 6.7 eat your heart out. Haha

Sent from my SPH-L300 using Tapatalk
 

Dave c

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Jul 7, 2013
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Yes jeremy wagler and brodax.
Just spend the money
You will be less into them and they flow 300 cfm unported.
I bet 400 cfm with a good port job.
That 3000 crank hp worth of air
Schied billet 6.7 eat your heart out. Haha

Sent from my SPH-L300 using Tapatalk


NGM has them brodix heads too,and said all out flow just over 300 CFM, i was dissapointed with the flow numbers till i worked the numbers and realized that they could offer 200- 300hp+ more air! Plus they have good pricing.
 

x MadMAX DIESEL

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Dec 30, 2008
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Yes jeremy wagler and brodax.
Just spend the money
You will be less into them and they flow 300 cfm unported.
I bet 400 cfm with a good port job.
That 3000 crank hp worth of air
Schied billet 6.7 eat your heart out. Haha

Sent from my SPH-L300 using Tapatalk

Sorry but no they don't. They outflow everyone's but not that much