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New Turbo Set-Up For New Optimizer Rebuild

Is the HX40W from a 95 cummings a good turbo? Or is there a particular part number, year etc for the HX40W that I should use for my Optimizer build? I do see different syles, I guess it's the waste gate and actuator.
I do have the specifics on the 95 turbo.
Kit #3802619rx
Assy. #3533010
Serial# 1295658

THANKS
Best I can find on that turbo is that # is used in FORD truck & BUS Cummin's applications, keep in mind BIG Holset/CKO's HX40's have 4" in compressor & 4" out turbine and choice of T3/T4 outlets while a raceday exhaust adapter will allow for bolt on the turbo will not reach it's full potential w/o a full marmon or other full 4" exhaust, here is a chart for HOLSET turbochargers used in Dodge Ram Cummin's applications which can be adapted easy to the GM 6.2/6.5 platform...
http://www.myholsetturbo.com/images/holsetpartnumbers_2008.pdf
 
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Which particular part number would you suggest for my application? Thanks

First, a DS4 tune is specific to your VIN and added options "it's not one size fits all."

Big HOLSET/CKO HX40 turbochargers are now confirmed as a decent upgrade on the GM/AMG 6.2/6.5 diesel platform, the HX SUPER 40 & CKO w/850 cfm available can feed a potential 450 hp +- build, I say potential because of the lower efficiency of the IDI diesel design over a DI diesel must be considered.

While other factors like intake, head & exhaust flow fit into the equation for the ultimate build those are more a personal choice as opposed to being commonly done or even practical for those who do not have deep pockets or the skillset to do it themselves.

BIG AIR the denser the better is required for best results “so open air filters or air boxes are a NO, NO.” As I have found out using a BIG HX40 requires a full 4” intake & a full Marmon or other 4” exhaust from the turbine back no if’s but’s about it anything smaller becomes a restriction to be avoided.

BIG AIR is achieved via a bigger turbo, a belt driven supercharger or blower and compound combinations thereof, the objective being the most air at the lowest boost level tuned to the max rpm range of your GM/AMG 6.2/6.5 build. Quick Spool Valves (QSV), variable vain turbines, compound charging etc. are all considerations. Want instant acceleration then a blower or compound turbos are the ticket. Depending on how deep your pockets are or your level of skillsets will be the deciding factor in your final decision.

As for the stories about a big turbo not spooling or making boost until 2k rpm “my HX40W 18 cm2 CKO starts making boost @ 1.0K/1.2K from there boost up to 2.9 pressure ratio is instant, 2.9 pressure ratio equates to 42.50 +- psi actual.”

BIG AIR increases volumetric efficiency (VE) and that number increases with increased rpm I posted a chart relating to this in the 6.5 performance forum. I will say normally a 400 ci can flow 850+- cfm at a safe 3.5k rpm based upon how much BIG AIR you supply to increase VE but again keep in mind the loss of efficiency w/IDI diesel design so a % equal to the loss of IDI efficiency of rpm increase over the 3.5k for air being delivered is required.

An air box or canister having more than 850 cfm is critical (most are about half that) dual air boxes where space is tight might be the way to go for some, keep in mind the higher cfm flow capacity the better. Understandably, all the mods in the world will choke when the air filter can’t flow the required cfm for the build. Big canisters are costly but can be had on the cheap via military surplus, there are aftermarket spun aluminum canisters used off road and sandy environments that can be fit to the GMT400 by removing and relocating one of the batteries.

Obviously, larger diameter exhaust is required the biggest downpipe available aftermarket for the GMT400 platform is 3”, a straight 3” exhaust pipe can flow 747 cfm minus frictional losses in bends/radius it can become a restriction at upper rpm levels when running any BIG AIR turbocharger, supercharger or blower.

Charge Air Cooling (CAC) aka: intercooling (IC) is a must, it is achieved in a few different ways air to air which must be installed in front of cooling stack to be most efficient and the cooling stack should be ducted and sealed all the way to the radiator and IMO also applies to any H1 too so the cooling fan can pull air through them. Any CAC/IC mounted under the chassis between the frame rails is OK for minor mods but only works while airflow is flowing across them and really needs puller fans that turn on at slower speeds or stop-go-idle situations to make them more efficient. Next is water to air which can be sized and placed anywhere there is space to do so.

High pressure water injection 1.0k is another option using fogger nozzles directly into intake or sprayed on outside of CAC/IC, triggering can be done a few ways. Fact is 1.0k water injection can be used to prevent detonation in gasser turbo or blown applications so-much-so that ignition timing can be safely advanced instead of the commonly used retarding yielding big power numbers over what you already thought were great numbers. The war effort WW-2 applied this to aircraft and entities like RSR racing have been using high pressure water injection with their builds for a long, long time.

It is of the utmost importance to understand increased air density can make up ‘too a point’ for lesser cfm flow however big cfm w/massive air density is best. Insulating all intake runners, air box aka: filter box, turbine and down pipe are critical too.

EXCESSIVE HEAT which is well known to be the enemy of any engine and especially the GM 6.5 diesel platform. Another consideration revolves around upping the boost on any IHI/GMX turbocharger which not only superheats the air-charge it brings EGT/ECT/IAT to critical levels which IMO has more to do with cracking blocks and heads than any other factor “The GM/AMG 6.2/6.5 diesel can take the heat as long as a properly sized turbocharger, proper fueling and a good cooling system along with aux oil cooler is used.” Yes! There is an ongoing debate as to how much heat is OK? Consider, the HMMWV max engine coolant temp was listed (not sure if it still is) at 250dge f. then consider the military has very deep pockets to replace anything at any given time while GM has a listed lower max cooling system operating temperature. IMO the best coolant to use on a modified GM/AMG 6.2/6.5 is “waterless” my reasoning revolves around preventing steaming, cavitation and safer higher operating temps in general. Waterless coolant along with a programmable fan clutch is perhaps the best route.

PURE SYNTHETIC oils and lubricants because of their ability to operate at higher temps without breaking down are hands down best protection against the heat breakdown suffered by DINO based oils and lubes at lower temps.

There are other strings about my use of waterless coolant and the reasoning behind it as well as others views for and against which can be found on this site I urge you to read them.

Fueling is another story in itself, IMO a DS4 simply can’t supply the fuel needed when running BIG AIR there are rumored higher flow DS4 pumps being marketed however how much fuel can be delivered is a mystery best left to those who don’t know any better, however if not going for the bigger HP levels the DS4 will provide the best fuel control under all conditions.

I favor the custom built DB2 w/documented fuel delivery for a good reliable build like n8in8or is running w/o what I like calling the guessing game DS4 tuning for a BIG turbo it can’t possibly feed enough fuel too.
 
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FellowTraveler,

Really good information. I do plan to use an intercooler in front of the radiator, and relocate the battery for the airbox. I have 2wd auto. Which particular part number(s) for the HX40W would you recommend? I want to get going gathering parts.

Thanks
 
FellowTraveler,

Really good information. I do plan to use an intercooler in front of the radiator, and relocate the battery for the airbox. I have 2wd auto. Which particular part number(s) for the HX40W would you recommend? I want to get going gathering parts.

Thanks
Let's start with what features your vehicle has now, gear ratio, tire sizeany mods done already, etc. and where you plan to go w/mods and how is the vehicle used?
 
Okay, I thought I covered that in the opening few posts, no problem though.

95 dually pickup 410 rear gears 2wd auto, 235/85/16 big steel bumpers front and rear, truck box, work truck. Heath performance chip, straight exhaust, mandrel bent down pipe and crossover, air pump deleat, turbo master, EGT, TRANS, BOOST, gauges.

I have 10+ vehicles and this one is the fat girl that drives you to the party, can't quite live without her. I love this truck. Never going to be eye candy but I love her nevertheless and will keep her forever. I use this truck for towing and hauling. It's not always hauling heavy but needs to haul heavy when called on.

Now, I just noticed maybe a real issue. I have no room for an intercooler up front. The radiator, condensor, oil and trans coolers are hogging up all the space up front.

Budget is not really an issue. I want something reliable and strong. I'm in the middle of this 06 Navistar optimizer build so I wanted to get my bang for the buck while I had it all apart.

Whether I go with the HX40W or the ATT, I need to get on it and order the parts so I can get her back in service asap. I have decided to tear it apart and install the gapless rings, so any advise where to buy those would be appreciated as well.

Thanks for all the advice.

This site is definetly the best 6.5 site

Chris
 
Well I'll add my 2cents worth beings I'm in the same part of the country & terrain .....

A few years ago I built a 06gep motor to pull heavy...

I tested 4 different turbos/combos during the first year of running the truck, only really tested when pulling heavy..

I found the 35/40 hybrid with 14cm turbine was the very best of the 4 variations tested for my style of pulling.. and keep in mind I shift my own gears....

I have NOT tested the ATT...

With a ds4 a hybrid 35/40 with a 12cm turbine will spool fast and near no lag above 1500rpm..

I never towed over 65-70 in 5th and had no trouble getting the thing moving from a start or keeping temps down...

I had a cac mounted in place of the skid plate.... some don't like that spot and would butcher the front instead... go anyway you want to....

Just a word of advice, unless you throw a lot of fuel and like smokey slow spooling tha'ts what you will get with a true 40 on the turbine side, just not enough flow & fuel to spool a larger turbine side....

Very few will agree with this... but then again how many have tried a 35/40 hybrid set up right????
 
Keep in mind there are two ways to tell what RPM the turbo lights up at. From a dead stop and drop the hammer or rolling where you drop the hammer. My comments about the HX40II and ATT being useless below 2K RPM are from a stop and drop the hammer. Nothing happens below 2K...

When rolling the midsize HX40II would generate boost at a lower RPM than the ATT. It would also run out of air with high back pressure just before redline. The WG popping open was like hitting a brick wall till we torqued it down.

The reason for the difference is load and different amount of heat in the exhaust. The engine is speeding up too fast to fully wind the turbo up from a dead stop. When you drop the hammer in high gear you have more load and a steady engine RPM to fully wind the turbo out.

The nice part about the larger ATT turbo and getting the engine to run only in the upper RPM band that turbo works in - no intercooler. 15 PSI for the ATT is the same power on the dyno as 24 PSI from the HX40II. 15 PSI just isn't enough boost to mess with an intercooler. The ATT is generally at max boost around 18 PSI on and specific to the 6.5. (Full Load and towing a grade.)

The 500 RPM mentioned above is big. I assume we are not talking about 'it got .5 PSI of boost so it's spooled' like past useless discussions. Not saying so don't misread it as slinging mud here. No, just annoyed from the past as 0.5 PSI isn't blowing the smoke cloud out...

Total Seal would be where your 2nd ring is made gapless. Leroy Diesel can help with this. For the record I have a set of Total Seal rings in Patch and a cheaper set from Leroy that was made gapless for the 92 project truck.

Talked you into a stall converter yet? :woot:
 
There are more than a few different HX40 variants as evidenced on the post link for HOLSET PART NUMBERS I posted earlier that can be fitted to the GM/AMG 6.5td, the BIG HX40 & HX SUPER 40 (W) (HOLSET/CKO) come in gated 14 cm2 through 21 cm2 gated turbines as well as non-gated versions.

The DS4 pump simply does not have the fuel to fully use these turbos so they hit a wall in the very upper rpm band, however the extra air at top will keep EGT’s in check. I suspect HEATH, KOJO or others tuning the DS4 can give you an idea of how much HP the DS4 pump can feed…so consult them! I have the DS4 the other build has the DB2 moose…….

A DB2 can be tailored to fuel any of the BIG HX40’s & HX SUPER 40 as I had stated in earlier post HOLSET publishes its turbocharger MAP’S & identifies how much air flow is available these are critical to a proper build.

Race Day Mechanic can provide kits to allow for direct HX40wii & BIG HX40w install, Venders on this site sell the ATT (Mitsu TD0E-7 ???) which is a direct bolt on too there is plenty of feedback on both configurations on this site as well as other sites.

Keep in mind the gated HX40 when compared to same sized turbo of other brands spools faster as evidenced installs by others and myself…the web is full of commentary to this spooling.. Of the two installs of the BIG HX40 18 cm2 to include mine they are both HOLSET/CKO’s however one is using ‘HOLSET billet SUPER 40 wheels.’

Individuals are running the ATT w/o CAC/IC & w/o issues a HOLSET/CKO or ATT should have a CAC/IC for best results…IMO.

The HOLSET/CKO (SUPER DRAG or SUPER 40) can be had for as little as $200.00 delivered, while a real HOLSET is an average 6x that price, then figure in cost of install kit and gate control. Pricing for the ATT can be found at the boards ATT vendor….
 
Individuals are running the ATT w/o CAC/IC & w/o issues a HOLSET/CKO or ATT should have a CAC/IC for best results…IMO.

Maybe a water-to-air/IC.

In terms of a CAC/IC, IIRC that during the ATT's R&D it was found that a CAC was counter productive (specifically, the turbo worked better without the IC). Seemed that the additional plumbing did not help the ATT's performance.

So, the WTA/IC might work as it typically has a lot less (air) plumbing than a CAC/IC. But do not recall seeing anybody running an ATT & WTA/IC.
 
Maybe a water-to-air/IC.

In terms of a CAC/IC, IIRC that during the ATT's R&D it was found that a CAC was counter productive (specifically, the turbo worked better without the IC). Seemed that the additional plumbing did not help the ATT's performance.

So, the WTA/IC might work as it typically has a lot less (air) plumbing than a CAC/IC. But do not recall seeing anybody running an ATT & WTA/IC.
I'll have to look into that one because it sounds more a pressure loss across the CAC/IC issue related more to an improper fitment....like the small compressor inlet/outlet & intake pathway combined with the big compressor causing the issue....just guessing here 'like not enough flow capacity to begin with then addig an CAC/IC could restrict air flow even more.'

I have perhaps, the worst CAC/IC plumbing of all systems I've seen in the GMT400 platform and I get only a pound loss through the CAC/IC...this is the older between the chassis rail mounted unit......
 
Keep in mind the gated HX40 when compared to same sized turbo of other brands spools faster as evidenced installs by others and myself…the web is full of commentary to this spooling.. Of the two installs of the BIG HX40 18 cm2 to include mine they are both HOLSET/CKO’s however one is using ‘HOLSET billet SUPER 40 wheels.’

To be clear we are talking about matching a turbo to the existing setup or changing the setup completely. My example is changing the setup to use higher engine RPM suited for the large turbo. No right or wrong here just different ways of going about it. Most put up with the loss of lower RPM for a towing turbo and have not stalled their rig like I have. Peninsulardiesel also offers a large towing turbo with no low RPM spooling like the ATT.

I suggest the "spools faster" needs a context. From a full stop waiting for enough RPM for the turbo to light off is where most would notice. This isn't the turbo's fault - it's being outside the usable RPM range and waiting for the rig to get moving to allow the engine RPM to come up enough for the turbo to be able to spool.

If you are at 2500 RPM the GMx with a turbomaster has 5 PSI with no throttle. The ATT has about 1-2 PSI. Dropping the hammer at 2500 RPM no one is going to notice the difference of spool time outside of a smoke puff duration. You will notice the GM instantly choke like an asthma attack while the other turbos lean you back in the seat. If you are below the spool RPM you are waiting for the engine to get up enough RPM and if it can't and a downshift doesn't or can't happen there will be no turbo spool period.

Dropping the hammer at 1500 RPM will depend on the turbo if it spools or not. There IS NO TIME TO SAY FASTER! The ATT simply isn't going to spool at 1500 RPM. 10 min lugging at 1500 RPM = still no spool up. The automatic transmission will not allow you to stay at 1500 RPM with the hammer dropped. It, however, can lug you some and the solution is to downshift/unlock TCC sooner in the tune. Yes, get the engine to an RPM the turbo will light off aka spool at.

So watching the rig speed and engine RPM come up to where the turbo can spool isn't accurate to say one spools faster. If so I have the fastest spooling ATT around as it spools the moment the throttle hits the floor - as my engine instantly hits 2000 RPM.

My setup looks like this:
Instant 2000 RPM from a dead stop hammer drop.
The turbo light up gives us another 3-400 RPM for the total 2400 RPM stall.
Then I have maximum engine HP from 15 MPH, at over 3000 RPM, till OD kicks in around 65 MPH.
Add the extra gearing the stall provides via torque multiplication and it is even quicker.

Note: I have a 6.2 pump maxed out delivering about the same fuel as a stock 6.5 DB2 pump. So boost is 12 PSI vs. the 15-18 PSI I could get with more fuel.

 
WW, nice video thanks for posting. Looks impressive.

I spoke to Bill Heath today about the ATT. He of course is against it. Bill claims that his proprietary cam / hurricane turbo insert combo will perform much better than the ATT ever will.

Does anyone have any info on Heath's cam or Hurricane turbo cartridge?

Thanks yall !
 
For the turbo cartridge search wicked wheel. All answers are there. He makes $ from modifying the GM p.o.s. turbo so that's what he will endorse.

As for his proprietary cam When he first released it for sale I asked him about it with interest to buy one, my optimizer cam was scratched on #3 bearing. He said it is supposed to help because of the left bank of the engine taking longer to push its exhaust under the engine to the right side of the pickup where the turbo is. We spoke 10 minutes or so about that specific detail and that's why it's supposed to be SO GREAT. Then when I told him mine is centermount in a Hummer he said - it's ok it will work the same. How I asked? If anything in a centermount the left bank gets to the turbo 1/2" sooner than right bank. It went against everything he spoke about as to the ONLY REASON his special cam was better- his words. But he said it would effect center mount the same way...hmm.

He will talk down the ATT cuz he doesn't sell it. Same with holset. Go ride in a truck with a wheeled up Gm turbo, then a truck with ATT or Holset or Switzer. You'll know for yourself.
 
Bill told me that his cam will gain 40-50 hp or more over the stock optimizer cam.

Cam alone I call BS... his cam & his turbo together I still call BS.... show me .... he can't...

Ask for some kind of proof or something other than words and see where ya get.... if he doesn't SELL it it isn't any good he thinks...

I towed heave @ 20K + and ran a hybrid 35/40 and had more power than I ever needed, I don't know of many on this forum that have even tired it that way, it's ATT here just like it's Heath elsewhere, neither show much promise in the real world when compared to more better turbos...

I know a vendor that has 3 built hybrid turbos on the shelf, they are knockoff's but designed & built here for the vendor.. about the same price as the att .....

I will bet you won't like the att here in the south with the hills & such...
 
Absolutely no cam only in a 6.5 will get you 40 hp. We had cams cut billet that maxed out duration and lift allowing for maximum wasted fuel over 1 drop of hp gain. I'm talking valves nearly contacting pistons, and that couldn't get 30hp. Total bs. If he would build a stock engine-dyno then swap cam-dyno then he would quit making those rediculous claims.
 
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