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Every turbo vehicle that I have owned has had an intercooler. I have search the site to see if any 6.2 vehicles had one installed and have yet to find one.
Banks doesn't offer one so I was wondering why? Is there a magical power number or minimum boost presure that would be needed to properly use one. It seems the newer vehicle have them installed.
Thanks
my K5 does. Boost is the most thrown around term and usually mis-used term in the world. With the same engine in question, 10 pounds with T04 with a V trim wheel is enough for a little over 200 hp with a diesel. 10 pounds with a T76 inlet wheel is enough air for about 420 hp. Boost is not created equal, yet no body wants to believe it. If boost was boost, why would there be so many turbocharger configurations and sizes?
So are you saying that a intercooler would be a good addition to my truck. If so would it be a completely custom installation ?
Thanks
yes, mine is a powerstroke intercooler. the only thing left stock on my core support is the outer structure and the headlight mounts. Everything else has been cut out and re-fabbed.
Dezman125
01-14-2005, 00:10
Hi
I picked up an intercooler from a 2000 i think, dodge that i plan on installing in my truck. It will take a lot of cutting and fabing to get it behind the grill,but it was cheep and pretty close to the same size as the grill opening.
I think i may have found a turbo,hopefully it is in good shape,the pices are slowly falling into place :D
A turbocharger is an exhaust-turbine driven air compressor.
A charge-air cooler reduces the heat generated by that compressor.
You'll need a c\a cooler if you do a lot of heavy towing\hauling, requiring sustained Boost with hi temperatures.
If you drive a family go-someplace vehicle, you will not notice any improvement afforded by the 'cooler.
(Does, however, give you some bragging rights at most any event) ;)
BTW - Boost IS Boost.
If you drive a 3500rpm 400cuin 400cfm Diesel engine, 10psi can make 200hp.
Install a 2000cfm turbo off a 1000cuin 18-wheeler motor, you'll still only get 200hp outta your 400cuin Dlesel at 10psi, because your 3500rpm 400cuin Diesel engine only displaces\flows 400cfm, and 10psi can only force so much air into the 400cfm cylinders.
No matter WHAT the CFM flow rate that new turbo is capable of.
Cfm IS cfm.
If you want more power, you'll need to increase the PRESSURE, which forces more air into the 400cfm cylinders, increasing air flow, allowing for more fuel, allowing for more power.
If you cannot increase displacement - by bore and\or stroke and\or rpm - to increase engine cfm air flow, then increase intake pressure, which would increase EFFECTVE cfm air flow.
And that, folks, IS the secret to Diesel power -
900hp, 1200ftlbs torque outta a 360cuin six-cylinder?
222mph land speed record from a daily street-driven pick'em-up truck, which was driven and towed the tires\equipment trailer to the event? ? ? ? ?
You betcha! ! ! ! ! ! ! !
That's my story, and I'm stickin' to it........
Cold air is denser than hot air so if you use an intercooler you can get more air in for a given pressure
Simon.
Sorry JD but I disagree on the " boost is boost " statement . Your example of the different size turbos is a valid point except for the temperature of the air under boost . The smaller turbo will have to work harder , to get the same amount of boost , than the larger turbo . This amount of work will be seen in the different temperatures of the charge air and may further compound the problems of not running an intercooler .
Absolutely true, ewc.
Then comes the question of whether the turbine can develop enough power with low velocity\low volume exhaust gasses to turn the larger compressor wheel, which requires more power input to develop equivalent Boost at lower rpm.
Which required lower A\R for larger turbine wheel can then restrict exhaust velocity\volume as engine rpm\power increases.
Becomes difficult to manage a simple blow-off type wastegate into 'regulating' exhaust bypass, rather than just 'dumping'.
(EFI 6.5 PCM does that trick very well, thank you.....)
But, again, the point is - to increase power in a design-restricted flow rate engine requires increased pressure, EFFECTIVELY increasing cfm flow rate.
15psia(Baro) into 400cuin is ~400cfm@3500rpm.
30psig (45psia) into 400cuin is ~1200cfm@3500rpm
Add fuel to match - voila!!!!! Power!!!! At 3500rpm!!!!!!
Try that with a gasser!!!!!!!!
Feel free to correct, as necessary - my math\formula recall is atrocious..........
[ 01-14-2005, 05:42 AM: Message edited by: gmctd ]
Yep , that's where the drivabilty issue comes in . I'm at a disadvantage when it comes to vehicles as I have a Banks kit that is trying to be " tricked " into thinking the engine is bigger than it thinks . Heads are ported , with an increase of almost 40 and 30 CFM for the intake and exhaust ports , and a Crane Cam regrind . Single plane intake is worth almost 20 CFM over the dual plane . Next up is looking into working on the exhaust manifolds . So even though I may only get 7-10 psi boost , my overall improvement should be better than just the stock Banks . Of course this is theory , but I'm stickin' to it !
a turbo'd mustang with 17 pounds of boost from a 60-1 will run mid 10's in the quarter and make just over 500 hp. The same engine with a T76 and 17 pounds of boost will make 7-800 hp.
I have no reason to disbelieve that, grape.
Unfortunately, numerical data, posted to prove a point, can be very misleading, when removed from context, don't you think?
Since you guys figure power production based on mass flow in pounds, rather than simple volume flow in cfm, un-posted fuel rate and rpm figures could be used to determine the power increase achieved by, among other things, opening up the exhaust path, and intake path, for more flow at similar pressure conditions.
Right?
Same here - increased pressure means more mass per unit volume.
BUT (and that's a mighty big but) - we're severely limited by the actual DISPLACED flow rates that can be achieved below 3500rpm.
Takes more pressure to increase the mass charge.
Load it, pour on the fuel, exhaust volume increases due to heat, turbine spins up, pressure increases, add more fuel, heat increases even more, turbine spins faster - we still ain't got no volume increase from hi rpm, because we're loaded, and rpm is increasing slowly.
But that increased fuel and increased air mass due to higher pressure is making big fire across the long arm of the crank, and we're producing big torque numbers, toting that load in a most satisfactory fashion.
Turbocharged Diesels know how to work, when loaded, boosted and fueled.
And it doesn't require high rpm.
Just takes some re-structuring of what's known about gasser racing to adapt to a 'fuel, Boost, and low rpm volume also makes power' concept.
I did it - 'course, I don't let no numbers confuse me, none.... ;)
BTW - get a 2004 360cuin Cummins motor, and you got 6000rpm to play with.
And 45psi Boost.
And ungodly fuel rates.
Etc.
[ 01-14-2005, 07:44 PM: Message edited by: gmctd ]
You are also correct, SimonUK - but - a 1/2ton grocery getter, with occasional 3-4psi Boost and 150-170deg IAT, would not easily see any benefits, considering the cost of the system, in reducing that to 120deg, or so.
The system will pick up some heat from the coolant fan and radiant engine heat, so it does not always maintain external ambient temps.
A 2500 or 3500 working truck, requiring long periods of 10psi Boost and 240-280deg IAT, could easily justify the system, by the recovered power at 120deg IAT.
Imo - a working truck requires the c-a cooler, a play truck is owner's choice, to answer coxfmly.
[ 01-14-2005, 08:10 PM: Message edited by: gmctd ]
Wow, Talk about data overload! It's nice to know so many know so much and are willing to pass it on to those of us who know so little :)I have been a member for only a few weeks and kick myself for not joining when I originally bought the truck. I know my check book would have been happier...
I am in search of the best combination that will get me down the road. I was unaware that intercoolers could be so complex. It does sound as if my basically stock burb wouldn't benefit from the expence and labor.
I have also looked into a trans upgrade to gain that 4th gear but I think it would be better to keep the t400 and go with the gear vendor unit.
Any thoughts?
Thanks again for all of your help
dieseldummy
01-14-2005, 22:39
Adding an intercooler to a basicly stock vehicle would probably be a let down of sorts. I know when I added mine it increased turbo lag a little bit, the result of which was to increase smoke and decrease quick lowend torque around town... If you plan on towing very much I highly recommend it. Also, don't get to wrapped up in the boost wars, in the end you never really know what is going on anyways...
Boost is fairly simple to understand - it is related to pumped flow rate measured in CFM - volume - not very accurate, and Mass - weight, as related to air density, which is highly accurate.
If air was sold at a world-standard rate of $15.00 per cubic foot - $1.00 per pound of atmospheric pressure - the guy buying air in the Sahara would really be getting ripped off compared to the guy buying air in Antartica.
The Antartican's air-can would have a lot more air in it for his 15 bucks.
You can prove this with a simple, but dangerous, experiment -
First - tell the significant other there's a 50%off sale down at (fill in the local emporium, here).
This will remove most of the danger.
Take a clean, empty one-gallon metal can - paint thinner, gasoline, etc. - with a good sealable cap, outside and fill it with atmosphere.
Be very careful, here, to immediately cap the can off when filled, so as not to cause any ecological spills.
We don't want any of this stuff on the ground, or the carpet\flooring in your house, right?
Now, while 'the other' is gone shopping, place the filled can into the freezer for a period of time commensurate with accomplishing the experiment, and allowing for observation, summation, and removal of all evidence before the 'return'.
When you hear the audible 'carump!' from inside the freezer, the experiment is mature, and removal and observation of the can will reveal the somewhat mis-shapen, distorted can walls, caused by the cold-contracted air within.
Had you placed the can on a super-accurate digital scale at the start of the experiment, placing the can on the scale at this time would have shown the reduction in volume did not reduce the weight by volume.
1cuft of summer air weighs less than 1cuft of winter air.
Hot air expands, becomes thinner, less dense, lighter.
Cold air contracts, becomes thicker, more dense, heavier.
Air pressurized greater than atmospheric pressure becomes more dense, heavier.
Flow rate measured in Cubic Feet per Minute CFM can be very inaccurate because of that physical law(s).
Don't believe it?
Here's a pop quiz -
Which weighs more - a pound of lead or a pound of feathers?
Ok, looking over you guys shoulders, I see a number of you immediately circled 'pound of lead'.
So, since this is an 'all pass - none fail' curriculum, I'll restate the question -
Which has more volume?
And no, I'm not talking how much noise it makes when it hits the floor.
How much space or area - volume - does it occupy on your bench?
One (1.0) pound of lead is about the size of a golf ball.
I'm passing out boxes of four distinct sizes. Don't open them - just observe the relative dimensions, and the weight of each.
You can pass them around for weight-to-volume comparison.
I filled the boxes on an electronic digital scale, so the tare is accurate, to within a gnat's a(nkle)ss.
You guys with the two cubic foot boxes have exactly one pound of feathers inside.
You guys with the one cubic foot boxes have exactly one pound of feathers inside.
You guys with the six cubic inch boxes also have exactly one pound of feathers inside.
And whoever has the two cubic inch golf ball sized 1lb box - whatever you do, DO NOT UNTIE THE KNOT in that 60lb fishing line!
The 1lb of feathers was poured into 2cuft box till it was full.
Took a little pressure to get 1lb of feathers in the 1cuft box.
Required more pressure for the 1/2cuft box, much, much more for the 2cuin box.
Boost is taking that large original volume of air and putting it into smaller boxes, which can then be multiply stacked into that original volume.
We get the same volume, but much more weight.
An oxygen, folks, has definite weight per unit volume of air.
Which is why racers, aircraft, ships, locomotives, etc, use weight to calculate fuel consumption and air flow required to make power.
You won't hear an airline pilot pull up to the pump and ask for "a hunnerd gallons in that back tank, and check the pressure on that middle tire - it feels mushy".
Nope - he signs for a 15,000lb load of fuel, which he factors in with x-number of pounds of air, needed to make such-and-such thousands of pounds of thrust, all required to get his plane to Cleveland.
What's the relevence, you say?
Your ~400cuin 6.5L Diesel V8 engine is design-limited to 3500rpm - it pumps air at ~400 cubic feet per minute at 3000rpm, all day long.
(As an aside - a Buick 3.8L granny motor pumps nearly identical flow rate, at ~400cfm.)
At 3000rpm that's ~400cfm, and that is ALL it will ever pump at 3000rpm.
You can add Slick-Stuff, STP, Water-Wetter, teflon oil, cetane-booster, owl snot, whatever, but it can only displace - pump - 400cfm at that rpm - written in stone.
Smokey, Grumpy, Cale, Richard - cain't help ya, folks.
Snake, Big Daddy, Connie - guys that get all dressed up to drive 1320 feet - no help, here.
Put a turbocharger on it - still only pumps ~400cfm.
You could install the turbocharger off the TITANIC - with a skajillion cfm capability - on this motor, and that huge turbocharger will only output 400cfm into this motor.
Fortunately for us, if we could power the turbine on that monster with the low-volume exhaust output of the 6.5L, that large cfm capability could be used to make power.
How?
If the flow rate output of the compressor - turbocharger - exceeds the flow rate thru-put of the target device - the 6.5L turbomotor - that excess flowrate input will stack up in the engine intake tract as pressure.
And pressure makes little boxes outta big boxes.
If one big box of air can burn one tablespoon of fuel, then that same box full of 10 little boxes of air can burn 10 tablespoons of Diesel fuel.
See - it's the weight we're concerned with, not the size.
400cfm at 1psi vs 400cfm at 10psi - more flowed weight at same flowed volume.
That's my story, and I'm stickin' to it..........
Oh, yeah - the Buick granny motor? It's cranking 6000rpm to make ~400cfm.
Only three ways to make more power, folks -
Increase engine displacement at same rpm - bore and\or stroke
Increase rpm - 6.5L makes ~400cfm at 3000rpm, Buick 3.8L makes same at 6000rpm
6.5L would make ~800cfm at 6000rpm
Increase input pressure - Baro flows x-lbs\minute, 3x-baro flows 3x-lbs\min
Simplest. Easiest.
What's more - we already got it!
More Power to ya, folks.........
[ 01-16-2005, 11:59 AM: Message edited by: gmctd ]
dieseldummy
01-16-2005, 18:59
GMCTD, I agree with what you are saying, my personal experience agrees as well. I've tried a bunch of stuff and it all comes down to simple logic...
I think most people get caught up in seeing big boost numbers and not realizing that without the extra fuel to go along with the extra air , you're not helping the engine and might be hurting the process with higher EGT's . Boost by itself may help to cool the pistons and valves but at what point is it a liability ? Most of the group will agree that 10 psi is the limit unless there is an intercooler installed . To me boost is measuring a resistance to flow , not how much you flow .
By their very design , most production engines are built to appease the population with easy starts , low maintenance and fair mileage . Most of these run around 85% efficiency ( gas engines ) and with simple additions , such as air filters and exhaust systems , the efficiency may be increased .
Purpose built engines can have over 105% efficiency , without a turbo , but these are typically high RPM engines where fuel consumption is usually not an issue .
The interesting view is when comparing a diesel engine to a gas engine in terms of air flow and fuel use . The gas engine may have the same " flow numbers " of a diesel engine but will not move as much air at the same RPM . The fuel has a definite weight and volume and will displace some of the air in the engine . The diesel has a " dry manifold " and as such does not have to move any fuel .
On the opposite side of the equation , you have the exhaust system to deal with . If the system is properly designed and sized , there may be some scavenging of the combustion gases . This will increase the percentage of fresh air in the combustion chamber with a resultant increase in power .
All this comes down to , the more air and fuel you put in , the more power you get out .
Here's a thought - Boost is made BY fuel, not FOR it.
Any takers?
Yes and no . Kinda like the chicken or the egg . Without extra air no need for extra fuel . Poor exhaust system and extra fuel won't get you more boost , just higher temps .
Second thought - a Diesel engine cannot be damaged by too much air per unit of fuel injected - cannot be run too 'lean'.
If you owned a superflow flowbench you'd know that the only thing that determines total power output is air. Displacement has nothing to do with how much power is made....it has to do with how early the target power can be achieved in the rpm range. A 280 cfm head flowed at 25" will make the same hp on a 300 inch engine as a 400 inch engine, this is proven. Our race stuff is also in the 125-127% efficiency range anywhere past 7200(peak torque)rpm.
And I'll say it again, the same 300" ford with no changes will make 500hp at 17 pounds of boost with a 60-1 inlet wheel. Put a T76 on the same car at the same boost and change nothing else but fuel to make up for the extra air even though the boost is the same and it will make around 800hp. If boost was boost people would be wasting money buying a $2K dollar head unit to make more power with the exact same engine and cam combo.
I hear ya, grape - it's all about fuel trucked in with the incoming intake air charge vs fuel injected directly into a cylinder already full of air.
Gives ya a lot more control over made power.
And we've got fuel with 20% more BTU content than gasoline - liberate that excess with even more oxygen, and ya gets mo'power.
Right?
I would like to see - and I am being sincere, here - your built 6.2\6.5L engine on that dyno\flow bench, with posted data on the runs.
Everyone's done\does that with gassers - I'd like to see what really can occur with a Diesel, both DI and 18:1cr IDI.
And I am aware that time is money, on that setup, but noone has any real data on the GM Diesel.
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