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New Turbo Set-Up For New Optimizer Rebuild

C

Corvette502

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Location
Woodstock, GA
Greetings all, I'm new to this site but not new to the 6.5 t/d.

I'm refreshing a 2006 Optimizer 6.5 to go in my 95 Chevy Dually. Mods are Heath chip, complete exhaust, down pipe and crossover, manual waste gate, air pump delete, hi pop injectors. I have many trucks and I love my 6.5 dually. I'm want to use my stock injection pump in this rebuild. I want a better turbo. I was getting 15-17 psi consistantly with the stock GM turbo. I was told that a HX40 would be the way to go and this site could help me with ins/outs and an adapter kit for the install.

Any and all advice/help is greatly appreciated.

Thanks in advance

Chris
 
Welcome Chris.
Hx40 or ATT will do you well. Hx40 will take a bath t more building on your end, ATT is going to put you in similar area more complete kit available. Heath tune will do ok with both, a Kojo tune would do better.

How are you using it he truck- towing a lot, grocery getter, hot rod, etc?
 
Thanks for the reply Will.

I know that there is allot of discussion on the ATT vs. HX40. I currently have the performance tune from Heath. I do tow with this truck, but like the gitty-up of the performance tune. My guess is the HX40 is better, maybe more costly with the intercooler, fab/adapters etc. (May buy a kit if I can find one cheap enough) Not opposed to the ATT setup either, just want the best for my build. I need to make a decision soon as my engine is about to be painted and final assembly . Thanks!!
 
I had done the BIG (not HX40II) HX40w 18cm CKO (can be had in super 40 too) w/raceday's downpipe adapter and oil drain hose w/fittings and consider it the best mod overall, it changes the sound of the diesel more to a BB gasser sound. Keep in mind the BIG HX40 has 4" in/out and raceday's adapter brings the 4" turbine down to 3" which is great for most applications however sometime the HX40 comes w/4" Marmin plate to match up to 4" downpipe which is custom fabricated item & is recommended for best HX40w 18 cm turbine. The HX series Holset/CKO spool faster than any other turbo design.

I've read good things about the ATT (a BIG industrial mitsu platform) but other's who have or use it can better chime in on their results.

Be advised marine hi pops can cause loping/rough idle with OBD2 data link indicating a miss however it is not a problem in that it is a common prompt and cause no other issue other than an occasional and very slight feeling of a miss at idle only.....Some say the ECM an be tuned for the extra fuel of the Hi pops however I've not researched this so I don't know of anyone who has done it.

A CAC/IC is a must as is a sealed & insulated airbox , and insulated turbine/downpipe.

Tighten the tune for the 4L80 to firm or better....
 
Do you have the engine together all the way? How did you build it. Biggest regret I have with last time my engine was out is not putting in gapless rings.
What head gaskets and head bolts/studs did you use?
 
Welcome check out my site if you get a minute. I believe I have the best prices on quite a few items, like head studs. Also offer a timing gear now too, anyway check it out.

Pics of your build?
 
Short of twin turbo or variable turbos a big turbo setup for the engine to run in that powerband is a different truck. While the engine is out shove a better converter behind it and stall it to where the turbo is in the RPM power band. The 6.5 simply doesn't have enough HP down low to back up the torque. If you love the tune now a 6.5 with a large turbo pulling like a fright train all the way to redline will be an experience. Starting just over 2000 from a stoplight with the turbo lighting off is ideal. When stalled there is NO reason to use the higher backpressure HX40II over the ATT.

Video of my 'Yank it and get off quicker' stalled 6.5.
http://www.thetruckstop.us/forum/threads/let-the-insanity-begin-time-to-yank-it.43647/

Again with feeling a Big turbo is not the small GMx that is spooled up from the 150 RPM starter till 2200 RPM. The big turbos become useful starting at 2000 RPM. Any RPM below that is light power cruising or a smoke show. This is not a long stroke diesel, but, a high speed diesel set up by GM to low RPM lug the shit out of it, but, the auto won't do that. Low RPM lugging turbo with a transmission allowed to use all 3600 RPM - YUCK.

Without a stall converter you are left with the weak factory TC clutch. Biggest challenge is backing up a trailer without 4 low being smoke and no go. With a stall it's smoke, turbo lights, and then rear wheels light up. So you STILL use 4x4 to back a trailer because the rear end burning out in reverse with a trailer gets hairy quick.

I have 30,000 miles of soot free clean oil on Total Seal Gapless rings. I can still read the marks under the oil on the dipstick with 4000 miles on the oil. No blowby.
 
Thanks for all the replys guys, food for thought for sure.

After talking to my buddy who has a truck setup similar to mine and running the HX40W, I'm considering the HX40W. If the combination doesn't work, I'll try the ATT. I'm 90% at this point.

Will L: I have the shortblock complete with ARP Studs, Felpro Gaskets. I could easily change the rings if it makes that big of a difference.

FellowTravelers Would you please explain: "CAC/IC is a must as is a sealed & insulated airbox , and insulated turbine/downpipe. Tighten the tune for the 4L80 to firm or better...."

WarWagon: I clearly understand your position from a performance position. I do have a 2wd dually and pull several trailers, so backing up is an issue. Also, I'm worried about MPG. I think for me, maybe a slight stall would work better but 2000 may be too aggressive for what I'm doing, but can clearly see it would be fun nonetheless.

Great site and responses guys,

thanks

Chris
 
The stall isn't all about 'performance'. It's about setting everything up to get the most out of the new turbo. Performance would be a blown 502 with nitrous like the Farm Truck... ;)

I am running the smaller 6.2 29 plunger pump vs. the larger 6.5 31 plunger pump.

The higher stall makes up for the loss of low RPM power with larger turbos by stepping over it. Below 2000 RPM you are more or less a NA diesel with a big turbo. Yeah the GMx feels snappy off the line and no one test drove a truck loaded... Big turbo will not be quick off the line, but, will pass the overspead GMx on a grade. It's better to have enough power to light the rear tires up rather than hung up without enough power to move. The only way to do this is let the engine slip to the RPM the turbo can light off. It also generates more torque like an extra gear. One can be careful...

When you are up to speed the TCC clutch locks up and the MPG stays the same. I am running a 2400 RPM stall. At speed you don't notice it. When I leave from a light or am under 45 MPH, yeah, it's there. Without it you simply wait to get enough forward speed for the RPM to get over 2000 before you start to get out of your own way. It's worse with high summer temps, the fan locked up, and AC clutch running.

The gapless rings have cleaner oil due to less blowby. I would pop the pistons back out to do the gapless rings. Worth the extra labor charge. At 40,000 miles and NO blowby for a 6.5 diesel is a statement that is not normally made. Seriously I have to pull the CDR to see anything at all.
 
Corvette502 said:
Thanks for all the replys guys, food for thought for sure.
FellowTravelers Would you please explain: "CAC/IC is a must as is a sealed & insulated airbox , and insulated turbine/downpipe. Tighten the tune for the 4L80 to firm or better...."
Great site and responses guys,
thanks
Chris
Click to expand...

Charge Air Cooler (CAC) aka: Intercooler (IC) = "Denser air"

Air Box aka: filter box sealed against under hood/bonnet heat & insulated to prevent heat soak = denser air.

Turbocharger turbine housing & downpipe should insulated to help boost and reduce overall under hood/bonnet heat.

Trans shifting should be firm to extra firm to prevent slippage that is tuned into them from factory IMO they simply don't hold up long to modified motor. A TransGo HD2 is well worth the cost and effort & I suspect Heath did do some tweaking of the shifting when he did your tune "always better to confirm this was done" & if not get it done....

As for Torque converters, if your putting down a good amount of torque there is a shift in aftermarket suggesting lower stall converter engaging before peak torque so the torque is available to do the work and the transmission will stay cooler this way, however, keep in mind the peak torque can move up or down from the 1.8k rpm GM posts because of turbo/blower torque multiplication, built in torque converter multiplication (which can be tuned by builder) with it's spec's for the 6.5td, I've seen 6.2 spec's down as low as 1.2k rpm's.
 
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I disagree with the shift in the aftermarket specific to the 6.5 and specific to single large turbo. Most other diesels have lots more power than the 6.5 and can in fact benefit from a lower stall.

Going with a bigger turbo is moving the power band over 2K. Lugging the engine below this is not the correct setup as it has no power waiting for enough engine RPM to light the turbo. We can generate all the torque we want, but, without the turbo lit up there simply isn't any Horse Power to back the torque up and get things moving. Again we are loosing low RPM power to gain high RPM power and MPG by removing the GMx. Having tried both the HX40II and the ATT the result is the same - better MPG and high RPM grade climbing power, but, zero power below 2K RPM. I even threw a Spool Valve at it and loved it, but, still had to get X RPM before it got with the program and got moving. In other words still waiting for the turbo to light.

Keeping the small turbo like the GMx, twins, or other turbo lit up at low RPM, is the only way a lower stall converter makes any sense. Waiting for the RPM to come up to 1800 peak torque from a stoplight with a trailer, AC on, and fan locked in... Well there is a more miserable can't get out of it's own way experience and that would be a NA engine.

You can always call Yank at 775-826-9955 and they will help you choose the correct converter for your setup. I sent them a video and that is where they suggested and built the 2400 RPM stall.

One more reason to get a triple disc converter - the factory clutch is a weak point. Towing they are worth ~50K miles before they won't hold anymore. To control heat the ECM will lock it up at WOT. It's not rated to handle that. Last 2 of 3 trans rebuilds were from the TCC slipping. The TCC was slipping and rather than rebuild I just tossed the Yank in - problem solved.
 
WarWagon said:
I disagree with the shift in the aftermarket specific to the 6.5 and specific to single large turbo. Most other diesels have lots more power than the 6.5 and can in fact benefit from a lower stall.

Going with a bigger turbo is moving the power band over 2K. Lugging the engine below this is not the correct setup as it has no power waiting for enough engine RPM to light the turbo. We can generate all the torque we want, but, without the turbo lit up there simply isn't any Horse Power to back the torque up and get things moving. Again we are loosing low RPM power to gain high RPM power and MPG by removing the GMx. Having tried both the HX40II and the ATT the result is the same - better MPG and high RPM grade climbing power, but, zero power below 2K RPM. I even threw a Spool Valve at it and loved it, but, still had to get X RPM before it got with the program and got moving. In other words still waiting for the turbo to light.

Keeping the small turbo like the GMx, twins, or other turbo lit up at low RPM, is the only way a lower stall converter makes any sense. Waiting for the RPM to come up to 1800 peak torque from a stoplight with a trailer, AC on, and fan locked in... Well there is a more miserable can't get out of it's own way experience and that would be a NA engine.

You can always call Yank at 775-826-9955 and they will help you choose the correct converter for your setup. I sent them a video and that is where they suggested and built the 2400 RPM stall.

One more reason to get a triple disc converter - the factory clutch is a weak point. Towing they are worth ~50K miles before they won't hold anymore. To control heat the ECM will lock it up at WOT. It's not rated to handle that. Last 2 of 3 trans rebuilds were from the TCC slipping. The TCC was slipping and rather than rebuild I just tossed the Yank in - problem solved.
Click to expand...

I agree with moving the power band up on the scale w/big turbo however tweaking the converters torque multiplication is generally used to make up for the losses on the low. On a DD towing say 5k not an issue IMO.

I don't tow anything so heavy that would make me want any higher stall speed and have not tried it so I can't honestly say it's bad except for higher transmissions temps which can be put into check....

Yes, I agree the stock clutch assemblies sux however aftermarket has come up w/triple and now quad clutch converters for the 4L80e.....consider, all the $$$$ spent on rebuilds you could have had built a 4L80e w/lots of overkill...

That is interesting why you removed the QSV in light of the fact they are billed as quick spool, which turbo did you use w/it?
 
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I didn't remove the QSV. Two separate 6.5's. The QSV was sold with the 1995 burb and ATT. Hit 2K rpm from a dig and prior to the QSV had 2PSI. With the QSV it has 10 PSI at 2K RPM. The Yank was for the 1995, but, never got to it. It went in the 1993 instead. Be fun to run both, but, given a choice the higher stall converter solves 2 problems: weak TCC clutch and no low RPM power. The higher stall eliminated the RPM wait the QSV still had.

The extreme heat warning hot weather de-rating the engine (121 degrees F), fan locked in, and AC is an extreme load for a NA engine to get moving. Trailer not required. This trade off for grade pulling power was ok for me as I needed the grade pulling power more. NA engine I mean the large turbo is just a restriction below ~2000 RPM.

Now I have the best of both worlds keeping the engine in it's power band and when trans heat runs away the TCC locks up. I have not had any problems with excessive trans temps and I do have a temp gauge on it.
 
WarWagon said:
I didn't remove the QSV. Two separate 6.5's. The QSV was sold with the 1995 burb and ATT. Hit 2K rpm from a dig and prior to the QSV had 2PSI. With the QSV it has 10 PSI at 2K RPM. The Yank was for the 1995, but, never got to it. It went in the 1993 instead. Be fun to run both, but, given a choice the higher stall converter solves 2 problems: weak TCC clutch and no low RPM power. The higher stall eliminated the RPM wait the QSV still had.

The extreme heat warning hot weather de-rating the engine (121 degrees F), fan locked in, and AC is an extreme load for a NA engine to get moving. Trailer not required. This trade off for grade pulling power was ok for me as I needed the grade pulling power more. NA engine I mean the large turbo is just a restriction below ~2000 RPM.

Now I have the best of both worlds keeping the engine in it's power band and when trans heat runs away the TCC locks up. I have not had any problems with excessive trans temps and I do have a temp gauge on it.
Click to expand...

I my long journey w/GM 6.2 N/A & 6.5 diesels only time the diesel felt like a dog was when a charge air cooler (CAC) hose popped of the 6.5's "a N/A 6.2 has way more power down low when compared to the aforementioned situation" so I'm not in agreement about the diesel feeling like it's N/A under 2k it's highly unlikely because a turbo any turbo is blowing past the air pressure in your AO and IMO if it takes 2k to wake up then perhaps consider sizing it to better suit your needs.

If a big turbo 6.5td feels like a dog under 2k then it's not huffing air down on the low "simple fact Holset/CKO when compared with similar sized turbo's from other manufacturers brand name or CKO spools quicker." There are ways to load a big turbo gearing and torque converter multiplication rates then there is adding more fuel.

People get lost in all the turbo sizes and applications, from what I have gathered any turbo designed for heavy industrial use is doggidy dog down on the low and yes a QSV helps that some but nowhere as well as it does on a turbo designed for road use.

I'll stick to the lower stall speeds as I can't imagine hot rodding stop light to stop light w/a big Burb............
 
Sure you can retard timing in specific areas on the DS4 tune to help spool the turbo. Perhaps you can expand on other ways to get these larger turbos to light off at lower RPM? @FellowTraveler in the interest of alternate builds can you expand on different sizing and trade offs some?

Huffing hot dry air is a challenge. You can feel the power difference on a cold morning. So I have a bigger loss of power and turbo performance loss than nearly anywhere else and the dry air here also adds to it. What may be ok for cooler and flatter areas of the country simply suck here when I have a 10% and 18% grade in town and it's 110-121 out. Even the 2003 HPCR 5.9 Cummins gets an unloaded workout and requires a gear change out of 5th, direct, for the grades in town.

We are stuck somewhat with 'old technology' on our Forgotten Diesels. Again modern diesels have solved this problem with complicated electronics and turbos. At this time there is no 6.5 aftermarket kit available to give you both low RPM and high RPM boost. (Few 1 offs out there, sure.) You have to trade something. The GMx gives up high RPM power with excessive backpressure.

I should do a video of driving around town rather than "what's it worth" flat out. The stall isn't always at 2400+ RPM to move. Engine RPM varies with how much coal I throw at the fire. So mild throttle is fairly tame. I do run at higher RPM and it will be around 2K RPM at 25 MPH. Perfect for a quiet residential neighborhood. :D Seriously if you can't see, hear, smell, and feel Patch coming in time to get out of the road... I digress it was loud before the stall. And if someone complains I offer them the ability to buy me a new $72,000 diesel truck or STFU.

But in the end this is what I did for my build and the Stall overcomes the lack of lower RPM. It's more than 'just a turbo'.
 
@WarWagon Hahaha!!! The same comment I gave to a neighbor in a previous house when I was n/a driving the truck (full throttle up to 25mph) no turbo and cold advance kicked in to boot. Then Hummers having half the engine compartment 1/2 open and the other half covered with a sheet of fiberglass. This guy (nice guy actually) was harassing me because his alarm system has microphones that play outside noises. I would leave for work @ 5:00 and wake him up. He finally programmed his microphones to shut off at 4:40 then back on at 5:20.
"How could you even go hunting in that thing? You'd scare away the deer for 50 miles!!!" I think my big truck just scared his Toyota.
 
WW, "Air density is the big issue", looking @ turbochargers to fit the 6.2/6.5 requires a MAP which tells you what to expect out of any given turbocharger @ different pressure ratios so it can be properly fueled +- a hair to that MAP. Evaluate the MAP's for the IHI/GMX turbos then look at the MAP's for other turbochargers. Keep in mind if a turbo can blow 850 cfm @ 4.5 pressure ratio (66 psi actual @ sea level) will not blow that same air down @ lower pressure ratios. I had posted what the 6.5 can flow cfm wise @ different rpm's the objective from here is a turbo that blows more air @ lower boost levels and as dense as you can get it.

Then there is the turbine size to contend with, 9 cm2 turbine is small for a 400 inch motor as you know GM was content with putting a small turbine and no CAC/IC topping that cluster f__k was cooling issues because of poor cooling system design and super-heating of air charge when upping the boost on the IHI GMx turbos..we dealt with it and many trials and errors was the result.

I have one of the first lower chassis between the rails CAC/IC it is ok if driven easy however in the next couple of weeks I will be installing an aftermarket Ram Cummins CAC/IC which is almost 5.5 x the size of current CAC/IC, I'll know soon if I need to run hi pressure water fogger to the intake or directed @ CAC/IC.

I have a suggestion for your AO that I know works in hot environments where a conventional air to air or air to water CAC/IC simply does not work this idea was eventually patented by FORD however they did not invent it, it's a CAC/IC using the HVAC to run a properly sized evaporator core installed into the intake air pathway custom fabrication required.

I will not comment as to what turbo is good or bad as it relates to the 6.1/6.5, I will say I don't buy pricey items that have their specs held as secret, I will however buy it 'if it is on the cheap that's why I bought the full sized HX40w 18 cm2/CKO.'
 
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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
 
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