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Head flow info

So looking at your graph Chris it looks like the P400 flows a bit more CFM during earlier lift.

Are you saying looking at the numbers for the P400 for intake CFM vs exhaust CFM.

140/184 *100% = 76.08% still needs 9-10% increase in flow through the exhaust valve / runner to be in known performance range of within 85% of each other ????

And or you would have to look at each point and maybe do a % difference graph line.

I am over my head but am guessing you need to know how each flow test was conducted? What pressure differential was used and at what the CFM correction is used ie pressure and temp. I assume sea level at 78F but may be different temps ie at sea level and 70F and that might be an appreciable difference. Not in the same graph as much as different test different benches etc. ?????
 
You are right to all above, the info on the table given in a later thread, but all is repeatable, this thread is looking for other data, not about the chart I used as a example...

Les, that is one of many known sets flowed to get a true picture through the years..
 
I will give you that , not many are porting these heads . Mine are the 99 castings . When I started this , my BBC heads were in the shop getting done . Asked him if he could look at the diesel heads . Air flow was all he was looking at , not if they were gas or diesel . Checked the intake today , one of the inner runners is 196 cfm and one outer is 193 cfm all at .500 lift . Pretty useless as you will be lucky to get past .400 lift on the stock cam . The Crane I have is around .440 lift , base lobe was .030 smaller after the regrind . As I posted before , the single plane flows 20 cfm more than the dual plane
 
IMHO the big barrier is the IDI closed chamber design and the limited rpm range as compared to a 400 inch gasser's or DI diesel chamber. In other words lots more boost is needed for IDI to really flow more cfm and any meaningful increase by porting will be a plus.
 
Yes, there are some walls that can't be moved or much be done like the IDI chamber....

For MY set, I am working to improve the low lift area of the path, working to improve the tork band... more flow down low will suit a tow motor more in the low rpm band me thinks.. it's just my theory..
 
sctrailrider said:
Yes, there are some walls that can't be moved or much be done like the IDI chamber....

For MY set, I am working to improve the low lift area of the path, working to improve the tork band... more flow down low will suit a tow motor more in the low rpm band me thinks.. it's just my theory..
Click to expand...
You got me digging through the web and with slight increase of flow through the IDI heads less boost is needed as you mentioned earlier. I see lots of boost and fuel will bring about +-100% increase in HP over stock then there are other issues like cooling to deal with I suspect anything less than a P400 or NAVISTAR w/forged crank would not give long service at that level.
 
How someone pushes their motor and for how long isn't my concern.

I was just searching to see if any shown data was out there in this area.. and not much looks like.

Cooling, this is my second build, the other motor was similar built and it had no trouble staying cool @ 18500 lbs... don't expect any this time .
 
IMHO boosted higher rpms will make up for any flow issues the IDI cylinder head has however feeding it becomes the issue unless going DB2 bull moose or better. I have no idea whatsoever what max safe rpm would be on a pre P400 IDI 6.5 but I do know higher rpms will surely allow more flow through them IDI heads.
 
FellowTraveler said:
IMHO boosted higher rpms will make up for any flow issues the IDI cylinder head has however feeding it becomes the issue unless going DB2 bull moose or better. I have no idea whatsoever what max safe rpm would be on a pre P400 IDI 6.5 but I do know higher rpms will surely allow more flow through them IDI heads.
Click to expand...

I already have a Unique Diesel "hotrod pump", so I'm certain I can feed all it wants...

I'm not quite sure what you mean above either.... run a higher rpm instead of working to help the heads flow more???

Here is a few early pics of the port work I'm doing right now, yea, I know the pics aren't very good and they aren't done just yet, still need some finish work...

IMG_0512.JPG
IMG_0515.JPG
IMG_0513.JPG
 
Well we know anything you can do to improve head flow & VE is a plus, I was just pointing out any engines capacity to flow more boosted CFM at higher rpm's this is where more power is hiding.
Head porting looking good and a good 3 angle grind on them valves and I suspect it will flow much better than stock.
I do know that polishing dry runners is not required as it would be for wet runners.
I'm wondering how low can the compression be brought down to on the 6.5td so a higher lift custom bump-stick can be used without drive-ability issues?
 
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As far as max rpm, I can spin mine up to 4500rpm. Doesn't seem to phase it. Seems to kind of hit a slow spot around 4200rpm. Although I'm sure that the restrictive factory exhaust manifolds are that cause. Which I am currently deleting. So will let you know.
 
6.5L said:
As far as max rpm, I can spin mine up to 4500rpm. Doesn't seem to phase it. Seems to kind of hit a slow spot around 4200rpm. Although I'm sure that the restrictive factory exhaust manifolds are that cause. Which I am currently deleting. So will let you know.
Click to expand...
It's possible the exhaust manifolds are a problem and since you have gone another route is there an internal manifold size increase over the stock 6.5 td, or just design difference? I would suspect more the turbine housing size and/or fueling but I'm not the expert on that topic, I don't know about valve float at that rpm or if that is even a consideration.
 
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Possible the exhaust manifolds are a problem? Wtf do you mean it's only a possibility? Helen Keller could spot that one...
I've been planning on building a center mount setup for some time but been too busy with work the last couple years. I went with the delta regrind but almost would like to get a custom grind done. Ideally a 18.5:1, motor would get you the clearance to go higher lift numbers, bigger exhaust valves, ported heads, custom fab center mount w/ large turbo would get you where you'd want to be...
 
crash2win64 said:
Possible the exhaust manifolds are a problem? Wtf do you mean it's only a possibility? Helen Keller could spot that one...
I've been planning on building a center mount setup for some time but been too busy with work the last couple years. I went with the delta regrind but almost would like to get a custom grind done. Ideally a 18.5:1, motor would get you the clearance to go higher lift numbers, bigger exhaust valves, ported heads, custom fab center mount w/ large turbo would get you where you'd want to be...
Click to expand...

Well, last I checked WTF & Hellen Keller have not given their opinions on it.

IMHO, the 6.5 IDI can't rev high enough for the factory manifolds to be an issue under most boost conditions, I suspect a 3" down-pipe would be a problem first now if your trying to make a race engine w/the IDI 6.5 IMO your money could be better spent elsewhere.

From lack of any real data on porting the inferior 6.5 IDI head IMHO it is hit or miss as far as good results go.
 
SCTrailrider, thanks for you and Unique diesel taking the time and $ to try this stuff out, innovation costs money, and the effort is much appreciated. most of it is above my knowledge level though, so some of this I cant even understand. :)

For the un-educated, what will this do? You mentioned it should improve low end grunt, which I am very interested in. Will it also drop EGTs and IATs? will it smoke less due to a cleaner burn?

Also from an un-educated standpoint, I dont see the big issue that FT sees with the pre-cup, as all that has to do with is the injection system, not the valves, free-er flowing air would surely swirl more and try to encourage better combustion in the IDI system, would it not?
 
Also, constructive criticism to FT: The word "can't" may be practical, but its not fun. :) IDI aint dead yet, dont be a wet blanket. :)
it is obvious the grumbly pre-cup cackle of the 6.5L links deep to ones soul, otherwise we would all say F#@& it and get a Cummins. :) I bought a duramax and immediately felt a disturbance in the force, and had to go buy a 431K miled 6.5L 5 speed to bring balance to the world again.... :)
 
Understand the passion for the 6.5 td or I would not own one.

The 6.2/6.5 IDI have their limits and after decades there are no great cylinder head improvements, decent bump sticks or pistons to clear a decent bump stick from aftermarket, so individuals tinker, tinker and tinker with mixed results, I've done it and still do, however I'm a realist and surmised early on that if aftermarket has not done it in the many previous decades it's more likely than not gong to be one off custom.

As IDI diesel go there very good reads on this site that point to the best designed IDI ever the Mercedes 3.0 six cylinder high rpm IDI quad valve. Yes it's apples and oranges between the 6.5td and the Mercedes 3.0 but it goes to show you what could have been but never happened with the 6.5td, VW, Ford and Navstar and other IDI diesel development.......YES there are transmission adapters for the Mercedes 3.0 to GM transmissions....
 
GM Guy said:
SCTrailrider, thanks for you and Unique diesel taking the time and $ to try this stuff out, innovation costs money, and the effort is much appreciated. most of it is above my knowledge level though, so some of this I cant even understand. :)

For the un-educated, what will this do? You mentioned it should improve low end grunt, which I am very interested in. Will it also drop EGTs and IATs? will it smoke less due to a cleaner burn?

Also from an un-educated standpoint, I dont see the big issue that FT sees with the pre-cup, as all that has to do with is the injection system, not the valves, free-er flowing air would surely swirl more and try to encourage better combustion in the IDI system, would it not?
Click to expand...

I don't know a good way to explane it.....

I have made silicone molds of the runners so it is easy to hold the runner in your hands and measure in places it's hard to get to in the head. The exhaust runner in stock form are tiny, much smaller than the manifolds are..

The only way I can think to show the restriction is a air hose, bend it and flow slows and psi builds, use a larger hose and remove the bend and more air will flow with less psi....???

We should have the next set of numbers this week, a head is on it's way to TX now, this will the 2nd test on the same head, nothing done but port work... then once it gets back to me it will be ceramic coated with heat stop in all the runners then sent back to TX. It then will get flowed again to show anything gained or lost in the coating process, then the same shop will do the valve work, different springs, unshrouding the chambers etc, then they will get a final flow test once done for final numbers.

I don't know how to describe the benefits of opening up the runners, I know I hear lots of talk in the race/performance motor field both gas & diesel's... but I won't attempt to talk anyone into it either.. all we are doing is attempting to find untapped power for ourself and show the good or bad with it...

I do know a forced induction motor likes big holes to flow the big amounts of air being pushed through them, if smaller holes worked then the big cube motors wouldn't spend so much getting the heads to flow more air...

Why would the lowly 6.x be any different, we add bigger turbo's, bigger exhaust, bigger IP's, bigger injectors, etc... what about the inside of the motor, would better flow not be a positive thing also???

Like I stated at the beginning of the thread, this isn't a area many will look at, most aren't looking for anything other than a bolt on power getter... most will see the numbers and not really understand what they see... that's OK, it's not a quick cheap addition to a build in most eyes anyway...

Edit... as for the cam... the p400 does have a billet cam, the cam is on the way to TX also, they have a "cam doctor" that will give all the specs for any cam... but I won't be making the specs public anytime soon, that's part of the R&D that cost, and I couldn't build any motor without knowing about the cam... if they didn't make changes to the cam they wouldn't have needed a new blank me thinks...
 
[QUOTE="FellowTraveler, post: 514552, member: 16413")

From lack of any real data on porting the inferior 6.5 IDI head IMHO it is hit or miss as far as good results go.[/QUOTE]

Well can ya give us any idea what good results would be as far as numbers go?? Have you measured the runners any at all and maybe compared them to anything??

And lack of data is the reason for this endeavor, Myself & John do see their is a need for improvements, but we both also need to see real numbers, not just believe something someone said...

Would it make all this better if this motor hit big on a dyno, or if a vendor said it gave X amount of power but couldn't or wouldn't prove result's??

Head porting isn't a fix all... it's another mod that will add to the package..
 
Will you be back cutting the valves?
Also you might try cutting the stems like this
valves_9.jpg

good article here
http://www.enginelabs.com/engine-tech/cam-valvetrain/ferrea-helps-explains-valve-flow-dynamics/
 
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