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You will see improved performance from the items that you mentioned. The sum total might approach 40 hp gain.
The fact is, it takes a system approach to make power with the 6.5... Power that won't go away on a hot day at high altitude. Sometimes, big power can be made for a very short time, but cannot be sustained for 200 miles of trailer towing. The heat management issue must be dealt with to sustain increased performance.
Quote:
Originally Posted by ronniejoe
I hope I have put togther a 'system' orientated improvement for sustained trailer towing. The next item next year will be a new computer, i was looking at the plug and play offered at US Diesel for $575 but now I am not so sure and will definately do more research on it before making any more investments such as this.
For a good perspective on how to do this (there are variations and other ways), read the series of articles in my signature (if you haven't already).
I just noticed that the articles have been taken down from the website. They are available in book form here.
I agree with the idea that to make sustainable performance with the 6.2/6.5 engine family one must use a package plan that includes
Good base engine buildup
Properly modified pistons
Heads that have been reworked to beef up the weak issues
A completely reworked fuel system.
Aftercooler is a must
A good free flowing performance exhaust system
Special attention paid to the cooling system to insure the ability to get rid of the extra heat.
Possibly a look at the vehicles gearing so the combination will be optimal.
To sum it up I think that many of the companies that advertise the goody yum items that supposedly add X amount of power are simply preying on the buying public and interested only in the $$$ they can reap rather than building a business built on honesty and trust.
Its easy to advertise wonderful numbers and there is always a certain percentaqe of folks that will rise to the bait and buy the product.
In the end however the customer is unhappy and feels that he/she has been ripped off resulting in the industry as a whole getting an eye of suspicion cast upon it.
In my business I try hard to go the extra mile and give the customer their monies worth and only advertise that which I can realistically deliver.
Its too bad we have people that dont have this work ethic.
The company that makes the aftermarket PMD replacement (I wont mention any names) has failed to live up to their claims and now does not return any phone calls.
Far too much of this stuff goes on.
It will all come out in the wash.
later
Robyn
I posted a question a month ago about pop pressure and got no bite on that one.
Since than I learned from the fellow i got new standard nozzles from that the pop pressure for my 95 6.5 was 2200 psi, so i set them accordingly.
Is this right or wrong??
The truck runs fine at idle as well as full load.
On a couple of 6.2's I have the injectors are set at 1700 psi, wich the manual calls for.
So I will ask again what pressure is hy pop supposed to be ???
Standard 6.5 Turbo pop, ~1900 psi, high pop = ~2100.
My feeling on the Hi POP units is that unless you are starting life off with a specially set up high output pump thats set on kill I would stick with the standard pressure injectors.
Hi pop will give a slightly better/finer spray mist rersulting in a better burn "maybe"
I also wonder what this is going to do over time to the IP when working things harder to produce the higher pressures.
I stuck a set of squirts in a 6.2 that I had purchased from a shop that I had not dealt with before and they had set them to 6.5 pressures.
The little diesel rat rattled really good.
On a cold morning it sounded like an unhappy powerstroke.
OH YEAH Buddy.
Never had any issues with it though
Well I gues I did set Mine a tad high at 2200 psi.
Well that's to bad, I aint gonna peel them back out.
The wife says the truck is climbing the hills like a raped ape sinds i changed the nozzles, we'll see how the pump is gonna last, it is in there for at least 180000 km.
Well last week I installed a 4" exhaust from JC Whitney and could definitely feel and hear the difference. The power increase although mostly likely modest is definitely noticeable. My Kennedy inter-cooler arrived this morning...
So i look forward with earnest to see how well it turns out with the cooler and installing new injectors, moving the FSD to an external mount and adding the boost controller. Thanks for the input, ill keep ya posted...
My Wife put over 6000 km on the 2200 psi nozzles since i installed them.Quote:
Originally Posted by simon
The engine starts and runs better than ever before.
One wiff of smoke the moment she fires, then no smoke at all.
verry crispy acceleration, lots of power, and it used only 1 ltr oil in those 6000 km. mind you i vented the CDR to the outside.
Total km on the truck 313400.
I am a happy man
Check this out
It appears all else being the same a larger nozzle will create a larger "flame" or more penetration is what it actually references. Maybe better overall combustion with higher fuel rates or better heat distribution into cylinder? Don't know if anything is measurable as far as power/performance but the image appears like there is a difference.
I hope this link works because I doubt I could find it again.
http://public.ca.sandia.gov/ecn/orifice.php
Couldn't find a spec, but I'd bet that is a common rail setup.......
That looks to me the bigger nozzle equals faster combustion ie penetration rate which matches the "marine" steady higher rpm operation. I don't know what the system is just thought it was pretty interesting.
That is a very cool link. It is interesting to see the difference in the spray/flame pattern at different temperature and pressure and nozzle size. Based on that, I'd say that bigger nozzles and higher pressure are a good thing as you increase boost. The higher cylinder pressure has a significant affect on the spray pattern and penetration, and the bigger nozzle with higher pressure would compensate (at least partially) for that.Quote:
Originally Posted by Hubert
136Mpa = 20,000PSI, defiantly common rail. For the 6.5 application I don't believe comparing a 2000psi injection event to a 20,000psi is apples to apples. But then again I can't find my Fluid Dynamics degree laying around either!!
I was hoping for some evidence against the mythical "Performance High flow Injectors."
We are not comparing 2000 to 20000 here. All this is showing is that with an increase in fuel pressure there is an increase in flame penetration into the chamber.Quote:
Originally Posted by AndyL
I thought the link was pretty good and does support at least a little credibility for different injectors for the "marine" application. 6.5 pressures are a lot lower and IDI is a different animal but I think the link does show fair comparison for nozzle size. It references penetration rate of fuel and flame front into cylinder. I did not see any documentation of any power differences but does show there is a difference in spray pattern/combustion to nozzle size.
It has always struck me that marine injectors/nozzles are OE name brand parts at least from all the reading I think they are OE for marine applications. We are not talking some joe injector shop marketing his modified injector. Is the HP rating of marine engines higher? I have assumed they are and thought the pump was turned up and engine set for more HP since adequate cooling could be guaranteed with the application. Combined with the fact economy is less of a concern with recreational applications and emission requirements are different too.
Like posted earlier several times it does not make sense to me that just changing injectors will give any appreciable HP gain. But after viewing link I think it can definately be argued injector differences can be matched for application ie I think marine injectors are better for steady hi RPM operation and or maybe higher fuel delivery. And then maybe not necessairly for anything other than better emissions. HP gains are probably due to IP fuel delivery increase only.
Hay guys now where do i start i just bought a 93 3500 dually with 6.5 td whats the first step to helping her pull a 28 ft 5th wheel weighing around 9k and will i be disappointed in comparison to my 454 gmc. Like to keep it simple powerful and reliable. thanks
In In my opinion, upgraded cooling system (I think yours has the old single thermostat setup), intercooler and good free flowing air cleaner. Once the intercooler is on you cam make yourself a boost fooler so you don't throw a code when you turn up the boost some. I'd raise it form the stock 8-psi to 12-14 once intercooler. A better exhaust with downpipe always helps.Quote:
Originally Posted by stacker
With the above it should be comparable towing wise to your 454 but get better gas mileage.
Art.
I am sorry if this has been answered before, however I have a 93 6.5 td an I was looking at the turbo, it is a GM-3 and there does not seem to be a wastegate on it. it looks like a rod with a spring holds a butterfly valve closed when the exhaust pressure gets enough it forces the valve open.
If that is correct How could you increase the boost?
Welcome to the Forums!Quote:
Originally Posted by 93GMCSierra
That thing you described is the wastegate. It's just mechanically controlled. Increase the boost by increasing the spring tension. By whatever means. Be careful, there is a point of no return (meltdown). I would not recommend adjusting it w/o gages. EGT, at least to keep from getting too hot, and a boost gage to see the results of adjustment.
Thank you, yes I am going to get some gauges, I have been looking into that, besides boost and EGT what other gauges are recommended.Quote:
Originally Posted by DmaxMaverick
I have had this truck for about a year, however I have only just started looking into how to modify it. I pull a heavy 3 car gooseneck but only on occasion an I like the power to buck the wind an climb hills but when not hauling I want very decent mileage as well.
Transmission temp.Quote:
Originally Posted by 93GMCSierra
Art.
Even on a manual transmission?Quote:
Originally Posted by TurboDiverArt
Oh, sorry about that. Didn't read closely enough!Quote:
Originally Posted by 93GMCSierra
Art.
I talked to a fellow member yesterday about an ongoing problem he's been having with his DB2 6.5. He told me he ordered and installed a "marine" fuel injection pump and matching injectors from a non-marine vendor some time ago. The engine ran horribly. Some time later he installed a freshly rebuilt on-road DB2, which helped, but the engine still ran rough.
Then, he ordered a set of stock injectors from another vendor (who doesn't advertise here). These were installed, but the two of the eight leaked fuel at the joint where the two halves of the injector meet. There were no markings on the injector bodies - anywhere. No manufacturer name, no model identification, nothing... Sounds like China to me.
The Robert Bosch injector I have sitting on my desk has "Robert Bosch" and "Made in USA" imprinted on the injector body...
So, he replaced these leaking injectors with two original injectors he'd saved that had 150,000 miles on them. The engine ran a lot smoother and they didn't leak. Now, he's thinking about replacing all eight injectors with new ones. I recommended he deal with a certified fuel injection shop that sells name brand parts.
The glow plugs.... He was recently sold a set of eight glow plugs... that did not have any identifying markings on them. The vendor claimed they were as good as or better than the AC-60G.
His low-compression 6.5 struggled greatly to start when cold, even after modifying the glow controller to produce a 15-second first glow.
While one of the injectors was out, he watched the tip of the glow plug while someone turned the ignition key to run. The glow plug tip didn't turn orange, it didn't turn red, it didn't glow any color... The truck owner could feel a little heat when sticking his finger down the hole (just short of touching the glow plug tip).
So, he's installed a fresh set of 8 ACDelco AC-60G plugs, which allow quick and smoke-free cold starts.
Jim
I have a 6.2 which i will be adding a banks sidewinder to soon. I have The DB-2 pump that has just been rebuilt and the fuel turned up a bit. My question is should I have the stock injectors rebuilt or buy new ones. And if the answer is new, where and what source should I get them from. Also I due have a good Diesel fuel injection shop close.
I personally would have yours rebuilt by a reputable shop and have them set to the top of the POP spec. Also request that they pay a little extra attention to detail and get them all as close to each other as possible.
This will make your engine run smoother all the way across the RPM spectrum.
IMHO this also stops some of the harmonic vibes that can lead to issues.
If the injector pop pressure is all over the map from one to the next it can vary timing a bit which will not help the cause any.
Good luck
Robyn
www.usdieselparts.com is a supporter of this site and has been in the diesel fuel injection business for 60 some years. They are an authorized reman/retail center for Stanadyne, Bosch, Delphi and others.Quote:
Originally Posted by alteredspeed
Jim
Have a injection pump question. Bought injection pump in the process of having it rebuilt. A guy i know said the pump # that i have is junk. He is a big mouth and a Ford Guy, (not that that is bad)LOL. Are all DB-2 pumps created equally? Or should i have the diesel guy stop rebuilding this one, a little worried scence i payed 100.00 for the pump and some where between 550.00 and 650.00 dollars to have it rebuilt, he said depending on if the cam ring is worn and a couple of other things. Is that price range fair? Buy the way the pump # is DB-2829-4267. My reserch showed it was 84-85 military pump. Pleas help I really dont want to waste money. (who does with diesel being 3.37 in VA)
Among the Stanadyne fuel injection pumps, they were more or less created equal. In part, the model number reflects its fuel calibration and any factory upgrades that may have been added through the years. That's why the model numbers change over time.
For example, if the seal composition or a governor ring assembly is changed, the model number will change. This allows the industry to know what the build and upgrade level is for a given pump.
Jim
Is the pump mentioned in my last post a good one or should i keep looking.
If you are running (or think you might eventually run) a turbocharger, the DB2-4911 is one of the best choices for the 6.2/6.5 - along with matching injectors. I'm not a fan of mixing and matching pumps and injectors. When we got to the fuel injection system in our 6.5 Project truck back in late 1998, I acquired a marine DB2 and matching marine injectors from Peninsular.
Otherwise, any 6.2 DB2 pump built since the mid 90's will be just fine for a 6.2. The various seals in the 6.2 DB2 were made from Viton beginning in 1983, which works fine with the ULSD. The quality of the pump depends on the quality of the rebuild. Not all moving components are replaced during a typical rebuild. The head & rotor for example, are only replaced about every 3rd or 4th rebuild. Things like pumping plungers and rollers, most bearings and all gaskets & seals are replaced at every rebuild. Other parts are replaced during a rebuild only when they don't meet Stanadyne's specs. I was told once that a Stanadyne shop doesn't make any money or even loses a little when they have to replace the head & rotor. Most pumps with bad H&R's are scrapped as a result.
Jim
If the pump is rebuilt back to MIL specs it will be a fine little pump for your oil rat.
Robyn
I received a call this morning from a very unhappy 6.5 owner. A number of upgrades and repairs were added to his '95 6.5, which resulted in losing about 8 miles per gallon. New cylinder heads, performance Prom, wastegate mods, FSD/PMD relocation kit, and last but not least - "40-horse" injectors were added.
To help isolate the problem, I asked the owner to re-install the factory Prom, then drive the vehicle long enough to clearly identify any fuel economy changes. If no help, I suggested he install genuine Bosch factory-spec 6.5 injectors. I asked that he provide followup, and I'll report here what he has to say when I learn more.... ;)
Jim
Hey MP--Any news from the unhappy owner?
The corelation between the gains in performance directly influence the weight of the right foot as in how it is applied to the loud pedal.
The more the turbo whines and the more the beast growls the heavier the foot becomes.
The lust for the adrenaline rush as the little diesel beast comes to life increases with every improvement along the power curve.
My opinion is that there is a great likelyhood that the fun factor is taking over and allowing the horse to drink heavily at the fueling pond (MPG) as in sluuurrrrp, YUM YUM.
Or more clearly the black smoke factor. :D
If I run my Dahooooley with a sane foot on the throttle the Town mileage will average about 15-16 and Hwy at 18-20
Now with the new chip and a few other things that were done the little pony loves to run and it feeeeeeels sooooooo good.
If Im romping it around and enjoying the power the town mileage will drop to about 12.
This very well could be the issue.
The only way to objectively acertain whether the power improvements are the culprit would be to have an objective 3rd party drive the truck very conservatively and see what happens.
My 94 Burb is bone stock with absolutely stock components including a KITTY.
The early prom is still in the ECM as is the 5068 IP still fitted to the engine.
This rig will consitently knock down 21=Hwy and 17 City.
Now as far as power goes, it would be pressed hard to yank a sick whore off a pot. :eek:
Bet me our friend here is not seeing a heavy right foot.
Power is heat and heat takes fuel.
Now there could be other issues that we have not heard about yet too.
Later and Best to all
Robyn
Actually yes... I've heard from him a few times since my last post - as recently as yesterday. He's been running the factory EPROM for the past few months, and the mileage came back. He's planning to upgrade the cooling system now, with the upcoming summer towing season.Quote:
Originally Posted by ThreeQuarter
Jim
This does not supprise me at all.
Most of the factory chips are very conservative when it comes to fuel flow.
If I remember correctly 68cc max is stock. The performance chips are in the neighborhood of 91.
Seems to me I was told that the DS4 is maxed out at 91cc
Along with some other changes that come with the chips this could certainly account for the changes in fuel economy.
Robyn
one question I have though, and this does depend on watching the foot that controls the pedal, if you upgrade for performance that means the motor works less at a given rpm, to maintain speed for example, thus in the long run you should see better fuel economy. is that completely false?