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Intake project

No, the difference of intakes is n/a vs boosted. There is no throttle plate, but the turbo acts as one for the reflective pressure wave. That’s why back when this started as an intake thread I mentioned running the runners. They don’t bring the greatest results in n/a engines, but boosted ones. Window sticker copy cat kids just started doing it on n/a gasser cars because they could afford an intake and hoped for a turbo later. Then the trend caught on and stores sell whatever people buy wether it helps or not.

The reason I said tune the runners is because it is a math problem and fabrication isn’t crazy to do. Round to rectangular takes time, but Chris is a pro welder.

There are better designed intakes for turbo diesel, but without a software to follow the actions, it’s a gamble.

think exhaust systems for a minute. Scavenging has far greater effect on non turbo engines because the volume change at the pressure differential creates a low pressure which helps draw the exhaust out of the nextcylinder. Add a turbo and the increase of back pressure kills a lot of that effect, but having it still helps. However the range of error in design is much smaller because of it.

That scavenger is all about valve overlap and how it relates to the pressure in the header (exhaust manifold).

Now you have a pressurized manifold (from turbo) and valve overlap of the intake valves.
But what psi from a turbo vs the exhaust header in non turbo engine? HUGE difference. So how small is that window for error before that scavenger effect- in this case disrupted air flow- kills all the gains one hopes for?

GM and the Duramax engines- just sketched it up on a napkin? Yeah right! Then Banks spent how many dollars in labor and software redesigning the intake for better performance?
 
(Continued from my last post)
I am excited to see what Chris comes up with. But open air flow isn’t the whole story. It would be like designing a set of headers by closing only 1 chamber. An improvement over stock? Most likely. But since you have 8 valves operating in sequence from one chamber-

That’s like the turbo headers Banks came out with in the 80’s for sbc engines. All the header experts said he did it wrong and running banks headers vs headman or hooker, banks did HORRIBLE on non turbo engines. But all that back pressure once the turbo went on and his headers killed the competition. Just by timing the pipes different lengths.

Keep in mind, the best intake for sbc on low vacuum performance engines back in the time the 6.2 was designed was the victor jr. GM paid them for rights on it. When Banks added a turbo, GM was brought along kicking and screaming. They weren’t going to invest more money for moderate improvements when they already shelled out for that intake. Run it vs the van intake- it will make you realize the stock one isn’t junk.

A pressurized intake regardless of 1,2 turbos or a supercharger will flow the same at the same pressure and volume. Yes different characteristics will do better at X rpm and so on, but his turbo is chosen and sitting on a shelf. Trying to maximize the intake isnt a bad idea, but if someone tries a “tank“ system like the Dmax, they can loose ground quickly- as me how I know- haha. That’s how I learned about the Victor Jr thing when GM was donating me hand grenades to pull the pin on.

An interesting article I read years ago showed Honda using an electric motor to operate the valve train while testing flow on their turbo Indy engines and had huge tank to supply the pressurized intake air. Must be great to play with millions for a 10 hp gain! Haha
 
FellowTraveler said:
I am at a loss with this statement!
Click to expand...
Haha! What I meant was, as long as the intake is positive pressure (instead of vacuum) the same intake manifold design characteristics will all apply. So if he builds an intake that does better than stock, it would help regardless of gm4 or Hx40. 50 gallons of air at 5psi is the same regardless of what gets it there.

yes better turbo, superchargers, etc will do better.
 
Well the runners I have aren't a total loss, they just aren't where I want to be for my use.
Below are a few pics, the last pic shows the flange and the size of it, I think if using the Holley upper for the Hiram it would fit, I will still finish this mannie just to work out more details for the next, the next parts will be after the new year before the shop has them cut...

Ignore the tinfoil in the valley, I used it to measure clearance on the truck...

@Chewy1576 is going to get measurments for me while he has his inter fenders off, I need the top of the valve cover to bottom most underside of the hood...

001.JPG
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Chewy1576 said:
I'll have a straight shot to the engine through the core support tomorrow after I get the radiator out. Stay tuned...
Click to expand...
How old are your motor mounts? And are they rubber or polyurethane? We’ll have to take that info into account when thinking about the measurements you take.
 
TSP,
Your tapered runners are interesting, and the links you posted earlier are something to take note of! While probably nowhere as efficient an heat exchanger as say gm's integrated air/coolant designs (LSA, LS9) for the eaton blowers, I believe the packaging is the right design direction.

So, let me first say I am not a dynamicist nor an induction design guru! My comment regarding the low/mid-range tuned gm TPI induction sys I think is valid, even w/o a TB.

In n/a induction you have "non-tuned" short runner (tunnel ram, hilborn, sheet metal) optimized for max hp/rpms. Then you have the multitude of "tuned" system designs.

The most rudimentary are the single runner per cyl passive designs, optimized for a limited rpm range (think TPI). These can be optimized to greatly increase VE within its intended range. I won't go further down the tech lineage, as a clean sheet design beyond that is most likely beyond our collective abilities and would require lot-O-cubic-dollars in R&D funds.

As others have already stated, tuned designs rely on the natural resonance modes/nodes that occur in a piped/runner induction sys. At a basic level, the resonant Helmholtz Fq's are determined by the shape and volume of the induction sys -vs- the stimulating source (IC event cycle). Think blowing into a empty beer bottle, that whistle/ringing sound is the cavity's natural resonant Fq being stimulated/energized.

Inside that beer bottle, a fundamental Fq of standing waves have now been established gaining amplitude due to the effect of constrained constructive wave interference. A gas-tube LASER works in a simular maner, but with photon emissions rather than auditory soundwave frequencies.

I digress, the TPI can and does produce meaningful positive intake pressure while in constructive resonance - even with the TB wide open! It's deficiencies are also a direct result of its tuning. Passed its intended operating rpm range (>4300RPM), deconstructive resonance sets up in the runners/plenum. This creates a huge spike in the resonant impedance. Effectively choking the runners to the point of being virtually a fraction of their normal cross sectional area, (IE, flow like sh*t). Owners of TPS sys have coined it "falling off a cliff" power loss, that's how profound the effects a tuned induction can have.

Now why do I care about all of that with a forced induction diesel? Well, the 6.5 is a very compact and short rod design for a diesel. It's low-end Tq is not on par with say a Cummins 5.9. And after reading countless "turbo upgrade" posts, there's one common denominator: the ideal operating condition is to utilize as little boost as necessary while cruising down the Hwy to ensure efficiency/mpg.

So if one could bolt-on a new "tuned" 6.5 intake sys that delivered increased VE at minimum boost levels (with no additional Exh back pressure), well I don't think I need to further explain? I would gladly trade away a potential top-end hp gain, for increased VE at lower rpms & low boost pressures! The overall under-the-curve gains would shadow the performance gain of a peak hp design!
 
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As a side note, the GM TPI was originally designed to make 350ci tq out of a 305ci engine. And lets face it, most of GM's 305 were econo weaksause power plants.

Much like how the 5.7 dropped the TPI's operating range down from the 305, if fitted to a 6.5 it would drop down to a near perfect sweet spot for a DD 6.5. The low/mid Tq gains could be significant.
 
94DieselSub said:
As a side note, the GM TPI was originally designed to make 350ci tq out of a 305ci engine. And lets face it, most of GM's 305 were econo weaksause power plants.

Much like how the 5.7 dropped the TPI's operating range down from the 305, if fitted to a 6.5 it would drop down to a near perfect sweet spot for a DD 6.5. The low/mid Tq gains could be significant.
Click to expand...
Begs the question how come the manufacturers don't tune the diesel intakes like a gasser's intake?
 
FellowTraveler said:
Begs the question how come the manufacturers don't tune the diesel intakes like a gasser's intake?
Click to expand...
They do. But just like using an exhaust manifold instead of a header, they don’t always put performance or best efficiency over cost of production or speed of assembly.
Remember they maximize profit, not maximize the vehicle. Also the whole noise thing- some guys hate noise so factory muffles it. Even the current power race L5P uses power and mpg robbing resonator on the intake tubing system. So it is always compromises, never best in any one category

I had a friend that before he passed away last year, he was an engineer at GM for years. His job was basically the breakdown guy- as in the team of engineers designed components, they build test vehicle, then a team chooses certain parts and gave him a list to redesign so it would make it through warranty 98% of the time. Yes they had to do some in warranty, but most shortly out of warranty would bring a ton of work to the dealership. His legal job description was that he redesign overly expensive parts to save wasting money. But it was made clear to him what his job was. He also worked for Toyota and Chrysler doing the same thing. I actually punched him once in the chest over the intank gasser fuel pumps in gmt400. He said the original one AC Delco made was about a million mile pump, they required the design change of them at GM. He had nothing to do with the lift pumps for our 6.5s- said that was another guy there or done by AC Delco. He said GM did specify inline shuttle pump- a known crap design... btw this is how we met. He was at a parts store replacing the lift pump in his hummer when I pulled up and helped him. Later figured out we spoke on phone a few times when I did the testing at my least favorite oil company on the engines.

He said the engineers almost always put up a few options of best power, best mpg, and best life on “paper”. Then as he put it “the powers that be mull it all over and come back with what they want”. He said the current power levels were easily obtainable back then, but would never have met current emissions standards.

So it isn’t crazy hard for places like Banks to make great improvements, they just pick a category like power over everything, and build to that. The software for computational fluid dynamics is out there and used by very few of the aftermarket world because of cost. But when you compare companies like Banks results to others, it isn’t hard to see where he invested his money. I remember watch videos a few years back on AFE and they literally talk it out and start building a few designs based on conversations like we would. Meanwhile Banks has engineers on staff that start doing calculus and typing away.

Gale doesn’t show all his tools in the video, but it isn’t crazy hard to get a tour if you are patient... I bet a dollar to a donut that software is 99% responsible for his latest income of differential covers. Proof everything he does isn’t about performance is that he offers that thing in powdercoat.
 
@ FellowTraveler,

I think Will L just about nailed it. Just good enough to compete with the other offerings for the model year. Keep in mind, the auto industry's tried & true strategy of the slow incremental performance gains per model year. Much like engineered-in obsolescence, tiered tech for the spendy'er models is all part of the game.

Back in the day, the L98 TPI was fondly known as GM's best truck engine that nerver was - because it was only in the Corvette and top-tier F-bodies.

Due to the the hp wars in the diesel world, all of the newer light duty (pickup trucks) have tuned intake & exhaust, along with variable vanes/geometry, or compound turbo(s).

Bottom line, with all of the - shall we say shortcomings of the 6.5 design: increasing boost & fuel only leads to block shattering increased peak cyl pressures. Increasing VE at lower boost & fuel = efficiency and longevity.
 
@ TSP,
Please don't take my comments as being derogatory towards your proto dev! Quite frankly, its almost amazing that someone is still developing for this platform, not alone possible offering new products for sale.

Not sure who it was that responed to this thread, but they sounded versed in induction/head flowbench work. They might be a value-added resource to consult with on optimizing your design. Fluid-dynamics is a lot of modeling with a dash of handworked flowbench blackmagic.
 
@94DieselSub if you do the “@“ then without hitting space bar start typing the persons name exactly as they have it written, within 2-3 letters it pops up options. Click on the one you want. Then that person will get a notification (check your top right part of screen, you’ll have one from me on this post). Also then you don’t have to type their whole name. It won’t turn blue until you post it.

As to who responded- his name is Chris the owner of TSP. Used to be common knowledge the best flowed heads available anywhere for this platform was from the now gone peninsular diesel. but before they went away, Chris did a bunch of grinding and head chopping apart and turned out better flow number than Peninsular’s best numbers.- so yeah you could say he spent a minute or two on a flow bench.

My comments to him btw, may sound like me telling him what is what. He knows me well from us talking, and I share my knowledge but am more asking him the questions on it with my understanding. We weren’t disagreeing, I was asking and theorizing he was explaining and teaching.
I probably should have made that clear for the other readers.

I do still think resonance from the valves closing and negative pressure wave bouncing off the inducer would have effect. But it would be minimal compared to the over all flow. Getting the tune perfect would maybe be worth 3% best. In comparison simple gasket matching vs stock hits about the same or tad more.
 
@Will L.,

Thanks for the heads up on the handle typing shortcut. Sorry if I missed your pm! I usually view various forums on my cell - yeah I know, I'm surrounded by pc cans, laptops & tablets and here I am viewing/typing this on this tiny cell screen.

BTW, my name is Chris too.
So Chris at Twisted Steel Performance IS a flowbench tech? I thought is was another who commented that he'd be doing great only loosing 5cfm with his runners - vs - the head alone?

And while I'll agree that gasket matching will gain flow, you might be shocked at what a tuned induction sys can achieve. If the spider truck intake was redesigned with longer runner length and a big plenum, I think sizeable VE improvements could be made. The GM TPI/ZR1 LT5, Lingenfelter/Accel Superram, and the First TPI sys all greatly improve VE -vs- a carb style intake (on a n/a gasser).

And yes I do realize after say 3psi boost these intakes would be not contributing. But realistically >60% of the time, the tuned sys could be greatly improving VE with the wastegate commanded open, (IE, little to no boost). All without any detriment to redline performance (on a diesel anyway).
 
Vic Edlebrock Jr. did a LOT of real world, hands on testing back in the day for intake designs based on where the desired powerband would fall - peak torque and peak horsepower and the effects on them based on rpm range and runner design. One of the things he discovered, which kind of flies in the face of intuition and the common "street lore" of building performance engines is that "gasket matching" the intake runner and head ports isn't as crucial to flow as is internal work to the head is such as unshrouding the valve, reducing the intake valve guide's profile and working on the curves of the roof and floor profiles of the head's intake passages.

On a SBC, he found that there could be up to 0.10" difference between the intake and runner ports and it had no real effect on the flow numbers. Much more than that and the turbulence created from the mismatch impedes the flow transition from the runner to the head. Now, if you're trying to wring out every last available horsepower in a super high performance, high RPM motor, of course matching the ports is standard procedure. Add forced induction and all bets are off.

Otherwise, matching the ports is pretty much a matter of bragging rights Friday night parked at the drive-in.

Of course all of Victor Edelbrock Jr.'s flow research work was done on the N/A SBC and resulted in the creation of some pretty famous dual-plane, single-plane and high ram manifolds, in various carburetor configurations, bearing the Edelbrock name on them.
 
94DieselSub said:
@Will L.,

Thanks for the heads up on the handle typing shortcut. Sorry if I missed your pm! I usually view various forums on my cell - yeah I know, I'm surrounded by pc cans, laptops & tablets and here I am viewing/typing this on this tiny cell screen.

BTW, my name is Chris too.
So Chris at Twisted Steel Performance IS a flowbench tech? I thought is was another who commented that he'd be doing great only loosing 5cfm with his runners - vs - the head alone?

And while I'll agree that gasket matching will gain flow, you might be shocked at what a tuned induction sys can achieve. If the spider truck intake was redesigned with longer runner length and a big plenum, I think sizeable VE improvements could be made. The GM TPI/ZR1 LT5, Lingenfelter/Accel Superram, and the First TPI sys all greatly improve VE -vs- a carb style intake (on a n/a gasser).

And yes I do realize after say 3psi boost these intakes would be not contributing. But realistically >60% of the time, the tuned sys could be greatly improving VE with the wastegate commanded open, (IE, little to no boost). All without any detriment to redline performance (on a diesel anyway).
Click to expand...
I always thought it would be fun to build up an engine utilizing the old Dodge RAM INDUCTION manifold setup, but, converting them to four barrel throttle body injection system.
 
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