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Long, slow build of my truck

Initial impression is I don't like it. Less smoke on a take off, builds boost slower, have to really push it to get it past 15. Stock MAP would give a little puff on a down shift and make 15 all day. We will see how it plays out.
 
pacificdrumma said:
Initial impression is I don't like it. Less smoke on a take off, builds boost slower, have to really push it to get it past 15. Stock MAP would give a little puff on a down shift and make 15 all day. We will see how it plays out.
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An HX35 should build boost very quickly, unless your your not putting down enough fuel. Any slow boost issues will only be amplified by going to an HX40.

Matt
 
bowtiebutler956 said:
An HX35 should build boost very quickly, unless your your not putting down enough fuel. Any slow boost issues will only be amplified by going to an HX40.

Matt
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What I am trying to say is that if anything, the 3 bar MAP did not help the truck from what I can tell. My understanding of the 3 bar vs. 2 bar is that the 3 bar supposedly reads 33% less boost than what is actually in the manifold, and therefore fuels harder to compensate for the lower boost (please correct me if I am wrong) and should result in slightly more fueling and not hit limp mode because the truck will not think the boost is as high as it actually is. That being said, with the original 2 bar MAP allowed the truck to EASILY reach 15psi, hit 18psi if desired, give a healthy puff of black smoke under acceleration, and overall move better than it did with the stock GM-4. With the 3 bar MAP, the truck feels more sluggish, struggles to make 15psi, and no smoke at all. I don't know if its because its a Chinese product vs. OEM or what, but tomorrow, the stock MAP is going back in.
 
Update from today -

Started tearing into the HX40 for inspection. When I was knocking the compressor housing off with the mallet, I somehow managed to chip the tips off of 2 compressor fins :mad: The metal appeared to be a little brittle, which seemed strange. Either way, it is in need of a new compressor wheel. I forget the exact measurements, but I am thinking it is a 58/83 wheel. The turbo is tight like the 35, so it shouldn't take much more than a wheel for it to be ready to go. I am not sure which turbo I would like to use yet. It has no issues spooling the 35 as an automatic, and I'm sure it would handle the 40 pretty well too. However, being that I want to swap to the NV, I think the HX40 might be a bit ambitious for the time being.

Next, after talking to some people and thinking on it for about a week, I have decided to use my NV4500 as a core towards a new/reman unit from SmartPartsAuto.com. I know that the parts to rebuild my trans would be around $200-250, and figure another $500+ for labor. This puts me pretty close to the $1,045.00 for a "new" NV4500. It should be noted that SmartParts do the 5th gear nut fix and brass Synchros meaning I can use gear oil not Synchromesh fluid. Additionally, they allow you the customize the transmission, meaning that I can order it with a 1-1/4 input shaft to replace the stock 1-1/8 if I desire. This company was recommended to me by the same friend Kyle who has been helping me throughout all of this. He has one in his '93 Dodge which has seen some hard runs in the last 20k that he has had the trans. This includes driving to and from AZ, towing a 6000lb load on the way home, day to day hard driving, and some 1/4 mile runs. The truck dynos at 350/875.

So for the time being, I will button up the HX35, get the waste gate actuator installed, maybe chip away at the upper intake some more, and save save save for the new NV4500.
 
Sorry to hear of the chips but at least that can be fixed. As spooling goes my HX40 starts a 1,k rpm and when I throttle it pedal to the metal it's boosts real fast to whatever I have it set at. Driveability overall is much better and at lower boost that GM8 was my speed is however limited to rating of tires.

I need to get a u-tube acct to post vids of the fast boost and Burb.

6.5td, HX40 CKO, Race day kit, DS4 bumped optic, early non turbo LP, 187 deg TDCO, gear drive, Fluid Damper, older Heath Tune but will get his newer HX40 tune, S&B box, Hi pops, 4"exhaust, built 4L80 w/HD2, 4.10 gear sets.
 
When I put a 3 bar map sensor on my truck, I didn't notice a change in fuel and boost would go just as high just as quick as it did with the 2 bar map. The 3 bar map allowed me to run up to 18psi with no problem, no limp mode and no defueling that I could tell. I guess every trucks is different.

Sounds like you should get yourself a custom ECM tune. Your gonna want that hx35 over the hx40 if your gonna be running a 5 speed. Thanks for the updates. Good luck
 
I guess I was expecting same or increased performance as 2 bar. From what I can tell, it only eliminates concern about limp because it doesn't let the truck boost high enough to hit limp.
 
Changing the MAP resistor doesn't change your boost. it changes how much boost your ECM 'sees', by altering the input scale.

With stock setups, that changes how the ECM will defuel things if the combined boost seems too high.
 
Jorge6.5 said:
Actually. You have a hx35 and a 40. You should look into making an hx35/40 hybrid turbo.
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I have thought about doing that, but being that the NV4500 is a higher priority, I am just gonna run the straight 35 right now.

JiFaire said:
Changing the MAP resistor doesn't change your boost. it changes how much boost your ECM 'sees', by altering the input scale.

With stock setups, that changes how the ECM will refuel things if the combined boost seems too high.
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Yeah, so I figured I would see at least the same boost I saw before, which I did not. I had previously put a 10k resistor in the middle wire going to the stock 2 bar. I wonder if that had any effect on it. And I wonder if doing that to the 3 bar would help.
 
You gotta remember, your (stock) ECM still thinks it has a GM-8 turbo (which it doesn't) and that it has vacuum control of the Westgate (which it hasn't). All the MAP is gonna do in your situation is stop your ECM from 'seeing' an overboost situation and defueling. You aren't getting to that point with your HX, so the 3-bar MAP isn't changing anything.

You have a bigger turbo, with better flow characteristics, so you show less psi on boost for the same amount of fuel. pushing more air than your fuel load needs will not net you more power.

Now, if you were pushing more fuel, then it would be useful.

***edit: I went back and re-read the whole thread. sorry, I thought you had changed to the -40 already. If you were defueling with a 2-bar and all you did was change to a 3, you should be ok. I don't see why you got less boost with a new MAP. Sorry for confusing things by responding before understanding.
 
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Keep your 35, get a new compressor wheel, guy on Ebay sells the size you need for $40 shipped for an OE one, and your off to the races, after getting a tune, :p
 
Update on the 3-bar, found a boost leak (surprise, surprise) on the coupler from turbo to intake, truck now makes 15-18psi relatively easily. Still feels a little more sluggish on a downshift than it did before. Oh well, at least it's not limp mode. Too dark to check for smoke, will do that in the morning. Have a gut feeling it just doesn't fuel as hard.

TVM- I've seen those wheels, $40 for OE sounds sketchy. I know it's cheap, but I think Im gonna keep the 35 for now, and really grind away at getting the NV4500 in. After that, I will turn my attention to fuel. I foresee a crossroads, I can either bite the bullet and do a DB2 on this engine or get a tune for less money. Decisions, decisions...
 
Back to the Tranny . . .

IIRC the NV4500 is good for 460'/lb (probably more, but that is the rating). Seeing as the goal is to squeeze more power out of the motor which will probably get it in the territory of the NV4500's torque rating, might think about getting cryo parts or just bite-the-bullet and get a new unit with cryo parts. Happen to know that Midwest Transmissions does cryo as well as the 5'th gear fix in a new unit.
 
Yep. Damn boost leaks. The make a huge difference. What cross over pipe do you have? Having a good non leaking one really helps
 
pacificdrumma said:
Update on the 3-bar, found a boost leak (surprise, surprise) on the coupler from turbo to intake, truck now makes 15-18psi relatively easily. Still feels a little more sluggish on a downshift than it did before. Oh well, at least it's not limp mode. Too dark to check for smoke, will do that in the morning. Have a gut feeling it just doesn't fuel as hard.

TVM- I've seen those wheels, $40 for OE sounds sketchy. I know it's cheap, but I think Im gonna keep the 35 for now, and really grind away at getting the NV4500 in. After that, I will turn my attention to fuel. I foresee a crossroads, I can either bite the bullet and do a DB2 on this engine or get a tune for less money. Decisions, decisions...
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Its not sketchy, he's a mod on the DSM forums and they are the real deal.

I hear you, money money or decisions, :(
 
Idk about the rating on the NV4500. I am well within that realm of 460ft lbs when I'm injecting and she has been holding fine. Not missing a bit except getting crapped on with another bad tranny. Damn deals, too good to be true haha
 
JayTheCPA said:
Back to the Tranny . . .

IIRC the NV4500 is good for 460'/lb (probably more, but that is the rating). Seeing as the goal is to squeeze more power out of the motor which will probably get it in the territory of the NV4500's torque rating, might think about getting cryo parts or just bite-the-bullet and get a new unit with cryo parts. Happen to know that Midwest Transmissions does cryo as well as the 5'th gear fix in a new unit.
Click to expand...

I checked them out, but I think I will stick with the Smart Parts trans. I will definitely be giving them a call prior to ordering anything, and going over what they recommend as a "power ceiling" for it.

Jorge6.5 said:
Yep. Damn boost leaks. The make a huge difference. What cross over pipe do you have? Having a good non leaking one really helps
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Stock pipe. I don't think its leaking, maybe worth replacing.

6.5L said:
Idk about the rating on the NV4500. I am well within that realm of 460ft lbs when I'm injecting and she has been holding fine. Not missing a bit except getting crapped on with another bad tranny. Damn deals, too good to be true haha
Click to expand...

I agree Morgan, I think if your trans has held up, a refurb one would hold up just as well.
 
Against my better judgement, I placed an order for a $40.00 supposedly OEM 58/83 wheel last night. My paypal should turn off after 10PM, oh well. I was going to need it sooner than later, and I have the HX40 bug right now. I think that when it comes in, we will install the 40, remove the hood and run a hood stack to see if the truck responds well. In the meantime, save, save, save.
 
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