thoughts
- Thread starter Tragic
- Start date
im not looking for fast, I just want my truck to pull, the most rpm's I will see is 2500 2700, i know that these blowers are for 2300 to 2500, they are also 1:1 ratio.
I have used compuonds and a single, both of which has the lower end lag, I want my truck when I put it in 1st gear and go to secound, I dont have that lag.
I should have mentioned that I also have 22.5 rims, when I put those tires on, it really started to act sluggish in 1st and secound gear.
turbo's that I have tried
single
hx35
hx40
s300
compounds
hx35 / ht3b
I have used compuonds and a single, both of which has the lower end lag, I want my truck when I put it in 1st gear and go to secound, I dont have that lag.
I should have mentioned that I also have 22.5 rims, when I put those tires on, it really started to act sluggish in 1st and secound gear.
turbo's that I have tried
single
hx35
hx40
s300
compounds
hx35 / ht3b
Tacoclaw
New member
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- Sep 29, 2011
- Messages
- 453
You will need a turbo, those blowers just doesn't work at higher RPMs. They move lots of air, but don't pressurize it well and that's what ultimately makes sure there's plenty of air getting through the valves at higher RPMs.
They worked on Detroits because their intake ports were huge, but our little 2" valve is another story.
You can have the turbo either before or after the blower, before will cause more parasitic loss (and belt slip) once the turbos spool since it'll be pumping denser air, but as long as the boost is kept moderate (30-40psi) it seems to be a simple, working approach.
Having the turbo after the blower will cut parasitic loss since the turbo will unload the backside of the blower and it will essentially be free-wheeling, but it's very easy for the turbos outpace the blower and start drawing a vacuum, which is very bad on the turbo. A large bypass can be used to prevent this, but the fabrication of it and making it work correctly aren't exactly easy.
Sorry if that doesn't answer your questions exactly, but hopefully it'll help some.
They worked on Detroits because their intake ports were huge, but our little 2" valve is another story.
You can have the turbo either before or after the blower, before will cause more parasitic loss (and belt slip) once the turbos spool since it'll be pumping denser air, but as long as the boost is kept moderate (30-40psi) it seems to be a simple, working approach.
Having the turbo after the blower will cut parasitic loss since the turbo will unload the backside of the blower and it will essentially be free-wheeling, but it's very easy for the turbos outpace the blower and start drawing a vacuum, which is very bad on the turbo. A large bypass can be used to prevent this, but the fabrication of it and making it work correctly aren't exactly easy.
Sorry if that doesn't answer your questions exactly, but hopefully it'll help some.
Tacoclaw
New member
- Joined
- Sep 29, 2011
- Messages
- 453
Oh yeah, everyone loves watching fabrication.
As an addition to what Roachie was saying though, what gears do you have in your axles? Aren't 22.5's like a 35+" tire? Let alone how much they weigh due to their build, regearing may be a viable alternative
I'm also surprised you didn't like the 35/3b set, that can't be a slow-spooling combo.
As an addition to what Roachie was saying though, what gears do you have in your axles? Aren't 22.5's like a 35+" tire? Let alone how much they weigh due to their build, regearing may be a viable alternative
I'm also surprised you didn't like the 35/3b set, that can't be a slow-spooling combo.
the problem with the compound set up (I did like it, just thought there was something better)
when pulling 10,000 pounds + it was really slow for take off, 4 or 5 secounds from complete stop to at least moving, also when pulling a steep grade, I get that 3 or 4 sec lag when accelerating, im just trying to smooth it out, not sure if I will be happy with results, as for the gears, not sure, what ever is stock for a d350 dually, I do know with stock tires had to start out in secound, since I put the new tires on, I have to start in first.
the tires stand 38" tall new
the tires + adapter, roughly 300 lbs
wanted to explain the up hill acceleration.
when you are cruising and you come to the start of the hill, if I give just a little pedal, I noticed there is a little lag 3 or 4 secs and then I have to put my foot into the pedal and by then I'm about 100 yards up the hill and I have to downshift, when I down shift it gives me the same 3 or 4 sec lag and a bunch of smoke, what I would like to try with the screw,when I start up a hill, I have a constant boost for the engine so that I'm not having to downshift once or even twice, I would just like to sail up the hill without any movement of my hand to the shifter, I'm sure it is wishful thinking.
when pulling 10,000 pounds + it was really slow for take off, 4 or 5 secounds from complete stop to at least moving, also when pulling a steep grade, I get that 3 or 4 sec lag when accelerating, im just trying to smooth it out, not sure if I will be happy with results, as for the gears, not sure, what ever is stock for a d350 dually, I do know with stock tires had to start out in secound, since I put the new tires on, I have to start in first.
the tires stand 38" tall new
the tires + adapter, roughly 300 lbs
wanted to explain the up hill acceleration.
when you are cruising and you come to the start of the hill, if I give just a little pedal, I noticed there is a little lag 3 or 4 secs and then I have to put my foot into the pedal and by then I'm about 100 yards up the hill and I have to downshift, when I down shift it gives me the same 3 or 4 sec lag and a bunch of smoke, what I would like to try with the screw,when I start up a hill, I have a constant boost for the engine so that I'm not having to downshift once or even twice, I would just like to sail up the hill without any movement of my hand to the shifter, I'm sure it is wishful thinking.
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roachie
Taco Master
- Joined
- Nov 2, 2007
- Messages
- 11,133
38" tires + another 800lbs in rotating mass + 10,000lbs of load + the truck......and you want instant boost? Never met a man with a vendetta for his driveline.
I like different, and I like blowers. But re-gearing your axle or using normal tires will be far easier.
I like different, and I like blowers. But re-gearing your axle or using normal tires will be far easier.
99GreenCummins
That guy....
- Joined
- Feb 15, 2011
- Messages
- 2,387
My thoughts exactly after reading all this. With a cam, the amount of fuel you have, that should be a lightening fast set of twins.
Sounds like you have experience towing but pulling hills are something you have to prepare for. You can't just roll to the bottom of a hill loaded, roll into the throttle and expect to top that hill without downshifting or dangerous egts.
Keep the compounds and regear. Sounds like you have 3.54. That's a tall gear for 38s in any application. Check to make sure of what you have but if it is 3.54. Jump to 4.10s at minimum and tune your afc.
As an aside, if your secondary is gating too low it will create a lot of lag as well because it will only build a few psi and then you have to wait for the primary to light.
Sounds to me to be 2 things. Poorly geared and possibly poorly tuned compounds.
What exhaust housing is on the ht3b?
For what you are doing, I'm not sure you would keep the egts in check with a blower and a turbo, let alone only a blower.
Sent from Tapatalk 4 via a Galaxy S3
As an aside, if your secondary is gating too low it will create a lot of lag as well because it will only build a few psi and then you have to wait for the primary to light.
Sounds to me to be 2 things. Poorly geared and possibly poorly tuned compounds.
What exhaust housing is on the ht3b?
For what you are doing, I'm not sure you would keep the egts in check with a blower and a turbo, let alone only a blower.
Sent from Tapatalk 4 via a Galaxy S3
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Dman1198
1 set of tires at a time
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- Jun 9, 2013
- Messages
- 159
If you decided to do a super-turbo a turbo in the 64-67mm range would be good (I'd say go fork the larger framed s400's or an hx52. There's always the option of Garrett but they're really expensive). Like taco said a bypass would need to be fabricated. Then once it's all together it NEEDS to be tuned properly. Even your pump settings would need some tweaking.
Perhaps do some tuning on your compounds before tearing it apart and treading where only one in this thread has. See if you can get quicker spool up and if all fails then try it
Perhaps do some tuning on your compounds before tearing it apart and treading where only one in this thread has. See if you can get quicker spool up and if all fails then try it
taco, I have the the pump just pushed all the way uptowards the head, I did not skip any teeth, yet
this is goig to be a little long (sorry)
I removed motor last year and rebuilt
I used 16.5:1 marine pistons
port and polished exhaust side only
fuel pump is for a 855d application backhoe, I have the denny 2 pin and thats really all I did to it because when I added the pin, she smoke like a raped ape, then when I put the injectors in, I have to be real easy with the pedal, if not, smokes really bad.
the cam is the euro 2 camshaft, these cams were for the double decker 390 horse power busses, they are the ones that take turist around.
as for the geometry on the cam, not really sure, i mic it out and it just has more time on the opening and less aggressive on shutting the valves.
marine cooling nozzles.
turbos
hx35 alone, this one was fine but still had the begining lag and fell on its face in the higher rpms
hx40 same with the lag, spools really nice and does not fall on its face in higher rpms
funny thing is, after I ported polished and used the lower compression pistons, I can only get maybe 18, 19 on boost, not sure why, I have done leak down test on all boots, I did a pressure test as well, still nothing, before the rebuild, she would hit 25 or 30, that was with not port r polished and 17.5:1 pistons
with the compounds, it would still have that lag in the begining and would screamm through all gears, most i got on the boost was 45 to 50( 50 would be on hills and the 40 to 45 was on flat)
I'm thinking it was not a good idea to use 16.5:1 pistons, because it seems to not have a complete burn with all the smoke roaling out(what pisses me off is , I did a bunch of therory runs on paper and on paper, it should have been a nice setup). I didnt think that lowering the compression that musch would really have any effect on it
i just thought that a blower setup would help on the front end with the no boost in the begining, I know that most of my problem is in the rear, just dont want to spend that much money in new gears, but if I want my truck to perform the way that I want it to, I know that I would have to.
I no longer have the ht3b, but I do have the hx55 not sure if that will work.
I think I'm going to take the pistons out and put regular marine pistons in.
this is goig to be a little long (sorry)
I removed motor last year and rebuilt
I used 16.5:1 marine pistons
port and polished exhaust side only
fuel pump is for a 855d application backhoe, I have the denny 2 pin and thats really all I did to it because when I added the pin, she smoke like a raped ape, then when I put the injectors in, I have to be real easy with the pedal, if not, smokes really bad.
the cam is the euro 2 camshaft, these cams were for the double decker 390 horse power busses, they are the ones that take turist around.
as for the geometry on the cam, not really sure, i mic it out and it just has more time on the opening and less aggressive on shutting the valves.
marine cooling nozzles.
turbos
hx35 alone, this one was fine but still had the begining lag and fell on its face in the higher rpms
hx40 same with the lag, spools really nice and does not fall on its face in higher rpms
funny thing is, after I ported polished and used the lower compression pistons, I can only get maybe 18, 19 on boost, not sure why, I have done leak down test on all boots, I did a pressure test as well, still nothing, before the rebuild, she would hit 25 or 30, that was with not port r polished and 17.5:1 pistons
with the compounds, it would still have that lag in the begining and would screamm through all gears, most i got on the boost was 45 to 50( 50 would be on hills and the 40 to 45 was on flat)
I'm thinking it was not a good idea to use 16.5:1 pistons, because it seems to not have a complete burn with all the smoke roaling out(what pisses me off is , I did a bunch of therory runs on paper and on paper, it should have been a nice setup). I didnt think that lowering the compression that musch would really have any effect on it
i just thought that a blower setup would help on the front end with the no boost in the begining, I know that most of my problem is in the rear, just dont want to spend that much money in new gears, but if I want my truck to perform the way that I want it to, I know that I would have to.
I no longer have the ht3b, but I do have the hx55 not sure if that will work.
I think I'm going to take the pistons out and put regular marine pistons in.
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fatty
VE
- Joined
- Mar 23, 2009
- Messages
- 959
I think with that DennyT pin you are probably putting too much fuel to it at low rpms which is why there's so much smoke and lag. Try using the stock pin for your next couple towing trips and see how she does. Also you may need to make adjustments to the starwheel for less pre-boost fuel.
