The forced air induction\more fuel thread...

[buddy]

It should just be less of an issue with our 6.5, because we dont go from 6000rpm to no airflow. We go from 3000rpm to 1000rpm when we get off the pedal with full flow, no air throttle and large displacement so good amount of air to flow. Its more likely with someone running a turbo with too large of a compressor with a small exhaust housing and wheel (higher shaft speed and backpressure).

The larger the inducer the more likely to have surging, so I can see why a 65mm inducer would have issues, especially if they did not up the exducer side. Seeing as Ive run the GM4 past 30psi without issues I dont think we will have a problem. It has a 53mm inducer with a 75mm exducer, thats a trim value of 50. Up to 60mm should not be an issue for us, especially when you maintain the same trim value, like with an 85mm exducer to get a trim value of 50. In general the higher the trim value the more it will "flow". The larger the inducer the larger "bite" of air it takes at a time.

A lot of those guys that can cause surge seem to do it for fun sometimes which is not good.

Dodge also had HX40s with that silencer ring in it, that actually covers up the "anti-surge" part of the compressor housing. I am not sure how well it works, but I would take out that smooth ring thing they put in the inlet.

 

[Slim Shady]

It should just be less of an issue with our 6.5, because we dont go from 6000rpm to no airflow. We go from 3000rpm to 1000rpm when we get off the pedal with full flow, no air throttle and large displacement so good amount of air to flow. Its more likely with someone running a turbo with too large of a compressor with a small exhaust housing and wheel (higher shaft speed and backpressure).

The larger the inducer the more likely to have surging, so I can see why a 65mm inducer would have issues, especially if they did not up the exducer side. Seeing as Ive run the GM4 past 30psi without issues I dont think we will have a problem. It has a 53mm inducer with a 75mm exducer, thats a trim value of 50. Up to 60mm should not be an issue for us, especially when you maintain the same trim value, like with an 85mm exducer to get a trim value of 50. In general the higher the trim value the more it will "flow". The larger the inducer the larger "bite" of air it takes at a time.

A lot of those guys that can cause surge seem to do it for fun sometimes which is not good.

Dodge also had HX40s with that silencer ring in it, that actually covers up the "anti-surge" part of the compressor housing. I am not sure how well it works, but I would take out that smooth ring thing they put in the inlet.

But when you take a larger bite of air doesn't drag on the compressor wheel go up , requiring more drive energy or a smaller lighter turbine wheel or a more aggressive turbine wheel cross section to overcome that extra bite of air, that probably would affect it more down low than once up to speed. So by having a large turbine section and a smaller compressor housing you could in theory drive the compressor wheel more efficiently with less back pressure or closer to 1:1.

But then a larger compressor wheel with a smaller turbine section would in essence do almost the same thing but would it spool quicker?:???:

 

[buddy]

Yes, larger compressor inducer means it will spool slower and generate more momentum/torque on the shaft, however a larger exducer helps spool faster with some detriment from more mass, but in general the bigger numbers on both help air flow when youre not boosting much so the engine doesnt have to create as much vacuum to suck it in. And it does not need to spin as fast to push the same amount of air (thats where the maps come in). So with the larger turbine that will spin slower you need the larger compressor to generate the same amount of boost, albeit slightly slower.

Large compressor with small turbine to make it spin faster is just a bad combo, and people can get or modify HX40s in strange configs.

Part of the HX40 discussion began with schoolcrafts high priced turbo for 6.5s that Kennedy described as a custom HX40.

 

[turbonator]

:nopics:

i will post up some pics tomorrow, the project turned out to be longer than expected( its like that with rust:mad2 i am at the point of putting the bumper back on and the grill in.... still need to fab up a couple of hood pins.... and a tool box in the back to put the batts, and the home-made provent, and a bracket for the remote oil-filter....:rolleyes5:.. still a few things.... need the truck for work monday...

 

[Pepperidge]

Seeing as Ive run the GM4 past 30psi without issues I dont think we will have a problem.

just how much did you push it "past" 30 psi?

I don't think I would consider it safe to push a stock turbo past 30 psi regularly...31 is about the limit on a Duramax's stock Holset turbo...any frequent trips past that and you are on borrowed time...I could be wrong, but I really can't see a GMx being any better/stronger design than the Duramax's IHI...JMHO

 

[buddy]

I wasn't recommending people run the GM turbo to 30psi or beyond. I was merely testing different configurations and programming. Probably was only running it like that for a month or so, testing things here and there, acceleration, EGTs, IATs, ECTs, backpressure (turbo efficiency) and top speed. So I could compare it to the ATT. It is by no means a good idea to run the GMx past 20 psi and its really inefficient and strains the engine.

 

[turbonator]

anybody ever here of the switchback turbo from blaylock turbos? seems to be another interesting version of the VGT/VNT/VVT style...
http://www.blaylock-turbo.com/switchbladeturbocharger.asp

 

[Pepperidge]

I wasn't recommending people run the GM turbo to 30psi or beyond. I was merely testing different configurations and programming. Probably was only running it like that for a month or so, testing things here and there, acceleration, EGTs, IATs, ECTs, backpressure (turbo efficiency) and top speed. So I could compare it to the ATT. It is by no means a good idea to run the GMx past 20 psi and its really inefficient and strains the engine.

sounds much more reasonable...the IHI for the duramax will make just a few trips to 32psi and above...(some have lived longer) but thats about the limit...it's not really a strain on the engine so much but the turbo will come apart...I was more concerned with a GMx coming apart at numerous runs above 30...

I'm still interested in how far "past" 30 psi you pushed it and for how long and how many times...really more from a drag racing scenario but post up from what ever perspective you saw it from i.e. towing, daily driving, short hard pulls, long hard runs of sustained boost etc...

On my new build I'm going with the an HTT 66/71/16 w/SS exhaust housing...I should be able to push 40psi + and still keep egts down...

 

[buddy]

My excursions past 30psi (like 32, 33psi) with the GM4 were simply drag racing scenarios, several 0-60, 0-120mph runs a couple to 130mph, which the programs maxes out at to allow without fooling the PCM. The engine also sounded/felt overworked at 3500rpm where it is supposed to make max horsepower. 120mph was doable with 15psi boost, although noticeably less power (slower acceleration) than when I could hit 20psi of boost. Then I tried more boost 30psi and it didnt really help, just sent the IATs over 300 degrees and engine sounded worse.

I am geared pretty high with 3.42 gears and 31" tires. This was all about 2 years ago though. Thats how Heath got his speed with high RPMs and high gearing (2.73 I believe) and twin turbos able to let the engine breath better than a GM turbo.

Then I ran the same stuff with my ATT later, and it worked better to get to 130mph much easier and the engine just humming along very pleasant. Just a little slower off the line, but more power beyond first gear and over 2400rpm.

 

[Slim Shady]

sounds much more reasonable...the IHI for the duramax will make just a few trips to 32psi and above...(some have lived longer) but thats about the limit...it's not really a strain on the engine so much but the turbo will come apart...I was more concerned with a GMx coming apart at numerous runs above 30...

I'm still interested in how far "past" 30 psi you pushed it and for how long and how many times...really more from a drag racing scenario but post up from what ever perspective you saw it from i.e. towing, daily driving, short hard pulls, long hard runs of sustained boost etc...

On my new build I'm going with the an HTT 66/71/16 w/SS exhaust housing...I should be able to push 40psi + and still keep egts down...

And you don't even have to worry about leaving your bottom end (crank and rods) on the ground like we do.

 

[turbonator]

sounds much more reasonable...the Holset for the duramax will make just a few trips to 32psi and above...(some have lived longer) but thats about the limit...it's not really a strain on the engine so much but the turbo will come apart...I was more concerned with a GMx coming apart at numerous runs above 30...

I'm still interested in how far "past" 30 psi you pushed it and for how long and how many times...really more from a drag racing scenario but post up from what ever perspective you saw it from i.e. towing, daily driving, short hard pulls, long hard runs of sustained boost etc...

On my new build I'm going with the an HTT 66/71/16 w/SS exhaust housing...I should be able to push 40psi + and still keep egts down...

did you install the holset on your truck? i believe that factory the older d-max's ran with the waste gated IHI turbos, and in 2004.5? they went with the garrett VVT that was computer controlled.... if it is a holset it must have been quite the pedestal that you fabbed for it... which holset is it?

 

[Acesneights1]

I don't see the factory crank pulley supporting a blower on top of everything else so call me the skeptic. If I am proved wrong, I will gladly eat those words. It can't support the original config unless someone out there is making someting stronger than the junk coming from China. Even the GM ones are Chinese.

 

[Slim Shady]

( i beleive them )

I don't see the factory crank pulley supporting a blower on top of everything else so call me the skeptic. If I am proved wrong, I will gladly eat those words. It can't support the original config unless someone out there is making something stronger than the junk coming from China. Even the GM ones are Chinese.

The pulley design is already done, it can't be done, I have heard that a lot in the past. But you won't be proved wrong cause it isn't happening anytime soon. The front of our crank can support the design, that was one of the most difficult parts to engineer. I have access to a lot of resources that are / work for the major players in racing / new design here in Detroit as far as design and machining. But I have told them that there won't be much going on in the near future in my little projects.

Did get to see something for the military that involved our beloved 6.5. BUT they told me that they would kill me (I believe them, actually had to speak with the facility manger after I saw it by accident) if they found out I told anyone, it was supposed to be real top secret. It is an interesting design piece. But I digress.

 

[Pepperidge]

did you install the holset on your truck? i believe that factory the older d-max's ran with the waste gated IHI turbos, and in 2004.5? they went with the garrett VVT that was computer controlled.... if it is a holset it must have been quite the pedestal that you fabbed for it... which holset is it?

crap...my mistake...brain fart I guess...I don't know why I said Holset...IHI is correct...

 

[nobby]

Well blowing a 6.5 has been done of course, I have no real input from the marine world. Sadly I have yet to come across a 6.5 in the marine field it just has not crossed my path. Wondering about the Australian set up and what mods their blower kit has for the drive set up. You'd like to think that if a company is offering a kit at a substantial price that they have a good experience with it, but then again........

If you go to bulletcars.com and dig they have an info page that shows for what it's worth a side by side youtube of a turbo and a blown 6.5
Cheers
Nobby

 

[Slim Shady]

I have seen that, I really don't like the newer screw style blowers, they are more efficient than a roots style to a point. You see most of them with a heat exchanger mounted under them.

The biggest problem with blower drive belts is that the newer smaller belt drives need a good amount of tension to drive the unit and installing that at the end of the crank on our motor after the pulleys adds to the leverage load on the end of the crank. So it has to be done in a different manner. the old style belts were cogged and don't require as much tension because of their width and the design. So those were considerations when we looked at the pulley design, right now it is just numbers and design, real world would have been nice to see, but that is not an option now.

 

[robzombie4551]

Here is some pics of the start of the install.

The good is it lines up with the intake,but had to shim upper 1/4inch. I cut the V-band portion off the turbo, and had to trim 1/4 inch off the upper intake.
Although I plan on making a custom upper in the future anyways, this was for people contemplating this swap with no welding/limited fab skills.

The oil return line looks like it was made for it, no mods neccasary, and the oil feed line no mods either except tapping for GM fitting.

The bad,[if you can't fab] is the receiver dryer will have to be move 2.5inches to the right so I can utilize the 3 1/2 inch D/P fitting.

I will have to locate a receiver dryer repair kit so I can lengthen the pipe and relocate to the position I want it. If anyone knows where to get one to cut down on my search time it would be appreciated.

Otherwise i will continue to update as I progress.

 

[Slim Shady]

Did you try looking for silver solder repair kits then swag an elbow from some line scavenged from the junk yard and solder them in, I know we used to repair lines, with it. get someone to add an appropriate elbow to the lines to move it to the position you need. Already been through a lot of this with our initial design. Now you understand the "dryer hose" no hard feelings. Otherwise I wouldn't be helping I would be doing something much less Christian.

Also looks like you may have to move the air box to clear the wastegate control. ?

 

[robzombie4551]

Now you understand the "dryer hose" no hard feelings.

First of all dennis I will admit when I wrong, and did. I had to trim the upper a little but could have taken more from the turbo but chose to keep as much material as possible on both.

Second of all stop trolling in ghost mode you're starting to annoy me. If You want to make comments show your face, I don't hide anything and neither should you unless you're hiding for some uknown reason.

Third; I knew about the exh. fab issues and can take the easy route or the route that I think would be most beneficial for this setup[which is more flow].

The dryer hose deal was poor planning on your part on something you should have worked out before marketing to the public.

I'm not selling anything, just sharing my mod.


I'm not competing with anybody, just sharing, treat it as such.

No more thinnly vailed digs at one other would be a good place to start,NO?

When you are civil towards me I will reciprocate,you also need to be a man of your word. If you need further clarification PM me and I will explain, I don't want to air this in public.

 

[Slim Shady]

You may want to leave a little more space between your turbo and intake, the lenghts grow a little as the pipes heat up. I was not making any derogatory comments, I just meant that I have been where you were at, and I am truly trying to give you suggestions that may be reasonable ideas. And what is invisible mode? explain that to me.