Engine/Transmission (1998.5 - 2002) Are my new mods suppose to be this loud??

[Fishin Guide]

Ok. regarding fuel pressure. The turbo will not affect fuel pressure. Unless it allows the engine to spin up faster than before and your fuel pump cannot keep up with pressure drop.



A bigger turbo often will result in higher cruise temps. Some will actually increase EGTs across the board. Usually this is because you don't have enough fuel to get it spooled. Also, if you now have a con trail out the back and you did not before, you are not putting enough cool air into the engine.



Double check all the connections and be absoltuely sure that you have no boost leaks. Also, double check the wastegate connection and be sure that you are building enough boost to kill the smoke.



If you had no smoke before and you do now, you most likely do not have any more power on tap. Also, turbos don't make power, they just allow you to take some unburned fuel and, well, burn it. This is where the power comes from.



Are you sure you have enough fuel to spin that turbo? I know nothing about it, so I have to ask.



Dave



Dave

 

[Clmsnow]

I would say there is a littlke more smoke off the bottom. . but then again the turbo does take longer to spool. As for more fuel, I am putting a pusher pump on it. Is that what you are referring to?

 

[TORQUE THIS]

What they mean by enough fuel is injectors. The DDII's you have should be fine with the HTBG.



It still sounds like you have a boost leak...

 

[Clmsnow]

I do notice a whinr from the turbo. . but I also notice a higher pitch whistle after say 15psi. It sounds similar to the sound I had after I blew an intercooler line off and didn't tighten it down enough. However, I have looked all over and all the clamps seem good. I did have the whole intercooler line off when replacing the turbo, anyway I could have screwed something up? Also, without the silencer ring, the stock air intake hose goes right from the AFE to the turbo. I can't imagine that one little hose clamp around the turbo makes that great of a seal. As for fuel... if I had bigger injectors like Mach 2's, would the turbo lag be even worse?

 

[Fishin Guide]

More fuel will lessen lag to a point. Some bigger chargers just take a while to spin. Seems like some of the other folks here know how it should act.



I would also go back and double check for boost leaks.



Dave

 

[TORQUE THIS]

If you hear a hissing sound around 15 psi, you have a boost leak...



I think I posted in the 911 forum for you also, check the boot on the drivers side, the one on the intercooler, it rubs on metal and puts a small tear in the boot. You won't be able to see it till you remove it.

 

[RacinDuallie]

What manifold are you using?... ... ..... I looked in your SIG and don't see a manifold listed??

If your using the stock piece- check it- it may very well be cracked:{ -and cause that unfindable whistle sound- stockers do crack easily.


And now that you have run it- recheck the torque on the manifold flange to turbo- nuts ( 4 )

And check the manifold to cylinder head bolts- they loosen up too.


Triple check the boots... ... .

Check on that downpipe clamp also... ... ... .


And- are you sure the wastegate rod is clear and not rubbing against anything?





... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... . Oo. * Oo. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .....





Oh- and I know you were waiting for this answer... ... ..... figure out this leak- give it a couple hundred miles- gently mind you... ... put that pusher on soon... ..... get a little harder on it (another hundred)... ... ... ... ... when the t-bo bearings are gently broke in- give it to it!! Be careful about it too... ... ... ... :-laf

 

[Lsfarm]

Common boost leak

Are you positive that the 90* aluminum elbow that is clamped to the turbo compressor outlet is firmly seated in the compressor outlet?? It has a machined surface on both parts and an O-ring to seal the joint.



On some instalations the elbow doesn't want to stay seated while you get the clamp over the two halves and then the fitting is 'cocked' and the O-ring is not seated. A boost leak and a whistle are the result.



Sometimes a second person needs to hold the elbow in place while the clamp is aligned and tightened. If it was installed crooked, it now needs to be removed and using a small file clean up the dents in the machined surfaces so the elbow can 'spigot' into the compressor outlet. It is a fairly precise fit.



With a bigger turbo you will get more smoke unless you were grossly overfueled before, and with DD2's you weren't overfueled. It takes more pressurized air to spin a turbo compressor through a bigger exhaust housing. So when you are running at say 1700rpm the old turbos with the small housing would be producing maybe 5-8 psi on level ground. At the same rpm with the same load on level ground the same amount of exhaust is exiting through a bigger outlet [exhaust housing] and can't exert the same pressure on the exhaust wheel and therefore much lower boost at cruise.



So before: small housing=more boost= more air to burn fuel=less smoke

But with the result that at high rpms the exhaust housing is very restrictive and doesn't let the engine breath well enough and the result is backed-up exhaust pressure [drive pressure] and high EGT's and less HP



Now: bigger exhaust housing= less boost at given rpm= less air to burn fuel= more smoke= slightly higher EGTs at lower rpms.

BUT you now have less backpressure [drive pressure] at higher rpms and a bigger compressor providing more air therefore lower EGTs at WOT, and therefore more power at higher rpms



With my '01 truck: Before: 75mph, 8-11 psi boost with HY35 [9cm ex. housing]

Now: 75 mph, 4-6 psi boost with PDR HX40 [16 cm ex. housing].

I picked up 2mpg during steady non towing cruise. Result of less backpressure. But I have slighlty higher EGTs at cruise and a bit more smoke/haze following me. I have much more upper rpm HP and lower max egt's



You will not have lower egt's at lower rpms with a bigger turbo. The above should explain this. You will have lower backpressure and maybe get better fuel mileage as a result [I did] You will have more high rpm HP with lower high rpm egt's.



Hope this helps Greg L

 

[Clmsnow]

Thanks for all the great info guys. . keep it coming. First off have the stock manifild, I did tighten all the bolts on it when I had the turbo off, I will check it again as well as the bolts on the turbo. As for the intercooler lines on the driver's side... I haven't looked at any of those. I was only looking at th ones on the passenger side, didn't even think of bothering with the other side. I will check again, both sides. I agree, it does sound like an exhaust leak at a higher boost level. Lsfarm... thanks for the explanation, that makes sense and describes exactly what is happening. Glad to know it is doing just like it should... aside from the exhaust leak.

 

[R-N-R]

Greg,

That was the best description in laymans terms that I have read in a long time.



Thank You,

Bill

 

[RacinDuallie]

Thanks for all the great info guys. . keep it coming. First off have the stock manifild, I did tighten all the bolts on it when I had the turbo off, I will check it again as well as the bolts on the turbo. As for the intercooler lines on the driver's side... I haven't looked at any of those. I was only looking at th ones on the passenger side, didn't even think of bothering with the other side. I will check again, both sides. I agree, it does sound like an exhaust leak at a higher boost level.

Don't forget to check- inspect that stocker manifold for cracks!!!

 

[Clmsnow]

I looked ath intercooler line on the driver side and it looked fine. The boot wasn't even rubbing against any medal or the fender. Should I still take it off? I can't find any leaks in the intercooler lines. Anyways else to check. Both the compresor outlet and exhaust outlet look like they are sealed up just fine. I definately notice the noise after 10psi. FYI. . I did blow a clamp off a week ago before I put the new turbo on. However, I fixed that at the time.

 

[RacinDuallie]

Heh Heh Heh- Your ears musta been burning.....

we posted exactly the same time:-laf

 

[Clmsnow]

I'll double check the manifold, but I doubt it cracked over night when I put the turbo on if you know what I mean. I notice a few exhaust manifold bolts loose when I was putting on the turbo and I tightened them down.

 

[RacinDuallie]

Look at it from top and bottom- carefully... ...

otherwise if you went and checked everything then you may have to pressurize the system and listen for leaks. (if all else fails)

The only other places to look are the Intake Horns gaskets or the plenum plate cover gasket... .....


Are you sure that's not the turbos 'music' your hearing... . sounds more turbiney with a real turbo... . stupid question here but I have to ask it

 

[Clmsnow]

NO I am not 100% sure... if there are any TDR members in the area I would love to meet up with them and let them listen as well. What are the Intake Horns and what am I looking for? I also added and AFE system at the same time, maybe it's related to that? It definately got louder, but there is also a distinct high pitch whistle after 10psi.

 

[RacinDuallie]

:-laf It's starting to sound as if the Turbo's Music is what your hearing!!!!!:-laf

The stockers wish they sounded like that and the AFE amplified it by taking the box from around your filter!!!!

Sounds like a jet engine?Oo. Then that's sweet music- I don't really listen to my radio- I listen to the sweet music coming from the T-Bo's!!!!!



LOL:-laf :-laf :-laf :-laf !!!

 

[Clmsnow]

I'm pretty sure it is a intercooler leak. I double checked again... I rearranged the line coming off the compressor, we'll see what happens. As for the manifold, it looks good. Wastegate rod is clear of everything. The intercooler line on the driver side looks good. The area people are talking about near the fender is not rubbing at all. There is a little kink and slack in the bottom elbow, but there doesn't appear to be any leaks or holes. If it doesn't work tomorrow I'll take that lower elbow off on the driver side and inspect even further. Worse case I could order all new lines from PDR and see what happens. The intake hose from the AFE to the turbo was not on perfect, I put it on a little better but I doubt that was it. Any other suggestions??

 

[RacinDuallie]

Your probally gonna have to pressurize the system and listen for leaks... ... ...

Remove intercooler inlet feed, place a rubber plumbing cap, from home depot- with an air valve sealed into it and hose clamp it on and pressurize- then listen and locate leak... .

Sounds crude but it is helpful in situations like this- might want to get 2 caps to isolate the intercooler if your certain the leak is there- one with air valve one without... ... ... ... ...

 

[Lsfarm]

Try this

Just put your original intake air filter and box back on, this will take five minutes and take the truck for a drive. See if most of the noise you are hearing is from the intake side of the system, I'd even install the 'snorkel' connector from the air box to the fender, just to get it as quiet as possible.



The intake horn is the square tube that is bolted to the head with four bolts on the drivers side and connects to the intercooler pipe. Where the horn is bolted to the head there are two gaskets, they can get blown out, also the aluminum plate that the intake horn bolts to has a gasket where it mates to the cast iron head.



You could try the soap bubbles method. Mix up some dishsoap and water solution in a spray bottle and spray on the gasket areas. You will see some bubbles if you have a leak.



If you do decide to pressurize the system be careful!. You are filling a fairly large container [intercooler and associated plumbing] with pressurized air. If one of you caps slips off it can cause some damage or injury!! There is a lot of volume of pressurized air to push a cap, like an 'air cannon'



Just out of curiosity, do you still have all the rubber gaskets on the top of the firewall that seal against the bottom of the hood?? If you got tired of pushing it back on the lip [mine comes off each time I open the hood] and just took it off, then you have opened up a huge noise leak from the engine compartment to the HVAC intake and windshield. This may be why you hear so much noise.



In my pursuit of a quieter truck I added an additional strip of foam behind the factory rubber gasket to seal out more of the whistle and intake roar. It is fun to listen to about three times then it gets old. [for me anyway] The added foam strip made a huge reduction in whistle in the cab.



With you changing so many things at once I think you may just have a normal system with it's associated noises. If you didn't have a whistle with the old turbo from a broken intercooler or torn boot or blown intake horn gasket then I doubt if one of these things happened while you changed the turbo. And you have said that you didn't get on it hard [yet] and create more boost than the previous turbo did. Lots of changes all of which can create more noise!!



Swap the intake, quiet down that side of the system and drive it, I bet you are suffering from " AFE intake ear-ache syndrome" :-laf



Hope this helps, Greg L