Hi folks, a 2nd gen person visiting - hope you let me peek in? I am posting this in the performance section because I hope to get input from people who took their stockers off and know them well.
Could you help me understand your stock turbos.
I have been looking for a 04.5-07 turbo for my 98.5 to try the upgrade that BigBlue24 did, and I am confused. From what I read, the 03-04 trucks should have a HE341 turbo. Yet if you look at the two e-bay listings, both list a 351CW, yet their turbines look different and one claims to be from an 03. Also, the exhaust elbow on the 03 looks like it is tapering down from 4" to like 3.5"?
Can anybody help me understand what the stock turbos actually are on 03-04 and 04.5+?
The 03 one:
http://cgi.ebay.com/ebaymotors/Parts...=p4506.c0.m245
The 04.5 one:
http://cgi.ebay.com/ebaymotors/Parts...=p4506.c0.m245

Thanks!
-P

 

The pictures for both show an HE351w. The first giveaway is the electronic wastegate control in the compressor housing.

I suspect that either the year was just a typo (03-04 is indeed a HE341 with mechanical and not electrical wastegate control) or the turbo was taken off an 04 truck that sombody put the HE351 on just like you intend to do. I suspect that it may be the latter due to the 3.5 exhaust elbow which was indeed used with the HE341 on 03-04. 04.5 and up used a 4" elbow.

 

But why does the compressor wheel look different on the two turbos: one has straight blades and the other has curved blades? Are there different versions of the HE351CW?
Then in fact if I bought the smaller elbow one, I could probably just use my existing 3.5" downpipe? Interesting option... I was ready to cough up for a 4" pipe and exhaust.

 

The blades on the second one are just chewed up, not curved. The apperance difference is from the damage.

 

The bidding ended on the one that was 05-06.

 

Yes, the bidding ended. I wasn't going to buy that one anyway, I'd be concerned about the beat-up compressor. I didn't realize that the shape was the result of the damage too! I will keep looking for one in a good shape. Still can't decide if I want to try the 3.5" elbow with my own exhaust or go with a 4"... I know 4" is better but I'd have to replace a whole bunch of stuff.
Thanks for your help!

 

Why don't you just send off your stock turbo and get it upgraded with an HX40 wheel up front. That would give you basically the same performance that an HE351 would give you minus all the plumbing nightmare.

 

That thought has occurred to me. But the 04.5 stockers can be had quite inexpensively and they have a wastegate that is much larger size than the HX35, or so I heard, and easy to open up even more if I wanted to. I was hoping to get lower drive pressures from the HE351 than those typical for HX35.

 

HX35 and HE351 have about the same size wastegate door from what I recall.
The HX35 also has a 12cm turbine housing vs the 9cm on the HE model=Less drive pressure with the HX35.

What are your goals with your truck?

Why are you worried about drive pressures being too high with a truck that is not far from stock?

Banks makes a 14cm wastegated housing for the HX35 if you are worried about drive pressure. HTT can upgrade your wheel up front to a 60mm from the stock 56mm wheel.

 

I tow a fairly heavy (10,000#) trailer at high elevations (6,000-10,000 ft) and have to turn off the box in the summer or it will smoke all the time. Looks to me like it wants more air. I did not monitor EGTs then, just now got a pyro and boost gauges. So the goal is to be able to tow across mountain passes in thin air without engine damage and being able to use my 90 hp injectors and the module, without spending a fortune (i.e. staying within $500-600).

 

Paul,
The 3rd gen turbo elbow/down pipe is completely different than one from a 2nd gen truck.
No compatibility...
You can swap cast iron exhaust elbows from an 05 to an 03 but not 3rd gen to 2nd gen. Completely different animal.

 

You could probably bolt up (once again plumbing nightmare) a used HE351 but drive pressures are going to be higher since it has a tighter exhaust housing. However your EGT's might be a little lower since it has a larger compressor wheel.

2nd gen turbos use bolts to clamp elbow and exhaust down pipe. 3rd gen uses v band clamps for both exhaust elbow and down pipe.

 

Thanks PourinDiesel, it helps. BigBlue24 did this on his truck bot he doesn't tow so it does not directly help me. His boost went up a lot though. It would be very interesting to see what the drive pressures and EGTs were doing; he did some high speed runs and looks like EGTs were better than with the stocker.

 

The most I have towed to date with the HE351 is 8K at 5000 feet elevation and 100*F. This turbo runs cooler. Although the exhaust housing is 9cm, it is open throat. Open throat 9cm is more like 11-12 cm divided like the HX35.

Paul, I got A LOT of crap from guys about how I was making a huge mistake, wasting money, and going to blow up my truck from excessive exhaust drive pressure. No one let up on me till I installed a drive pressure gauge. Well, drive pressure is not bad till you push this charger past 40 psi boost measured at the intake manifold. Drive pressure is never 1:1 but it just a few psi higher like 5psi, till you get over 35psi boost. I was able to get drive pressure up in the 60 psi range but I had the turbo singing 45+psi boost. When people saw that the drive pressure was reasonable, they figured that this turbo must not make any power, otherwise it would have higher drive pressure. So, no one let up on me until I strapped my truck down to the dyno and made 499.2HP. Since then, I get a lot of questions, at least one per week about the swap.

The fact of the matter is the HX35 is 15 year old technology and the HE351 is a larger and better designed turbo. It performs, you will be happy, and replacement costs will always be cheap for this setup.

 

Hey BigBlue24, fancy meeting you here You can see I am quite interested in trying the same swap as you have done and picking third gens guys brains here. I didn't realize you pulled a trailer with your setup. Well heck, I will look for a good deal on a 04.5+ and give it a shot. In the worst case it will be another unfinished project for me Of course I probably should clamp the wastegate shut on my HX35 first, I think I am probably getting all of 18 psi out of it