Timing for DD and MPG.

ok i thought i had read several threads about the SO being able to take more timing than the HO motors. well i will avoid that high of timing maybe 26* i am not sure if that will make very much difference or if the better bet is to wait on the answer for a smaller exhaust housing.
 
remember to that the gear ratio goes down so its also easier for you motor to do that work.. so more flow(mostly turbo) and less work = less egt.. but higher rpm combined with the less efficient exhaust side= less mpg..
 
here is a link to the turbo maybe someone else can read and understand it better than i can. i dont understand the map's that well yet still learning those. it also has the specs of both compressor and turbine wheels on there.


Bullseye Power Turbos
 
Chevycummins said:
ok i thought i had read several threads about the SO being able to take more timing than the HO motors. well i will avoid that high of timing maybe 26* i am not sure if that will make very much difference or if the better bet is to wait on the answer for a smaller exhaust housing.
Click to expand...
SO can take higher but not 30*. I run 26-28* and its too much in the winter.

I always wonder what's more important for mpg, rpm or egt?

I do think a 64mm will make you happier, billet or cast.
 
Your problem is that your not really on the charger. Its lagging so a smaller a/r will help you out more than anything.

Sent from my SCH-I500 using Tapatalk
 
yeah thought stepping down to the 66 from the 72 that was on it would of been better but it seems that i need smaller yet. i have talked to a few and they seem to say that 800* is fine and wont hurt anything but after having my 12v and only running like 500-600* it kinda makes me worry a little.

is it too much just trying to start in the cold weather? once it gets to like 25-30* i plug it in at night and dont have any issue at least so far.
 
Chevycummins said:
yeah thought stepping down to the 66 from the 72 that was on it would of been better but it seems that i need smaller yet. i have talked to a few and they seem to say that 800* is fine and wont hurt anything but after having my 12v and only running like 500-600* it kinda makes me worry a little.

is it too much just trying to start in the cold weather? once it gets to like 25-30* i plug it in at night and dont have any issue at least so far.
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If you plug in you shouldn't have any problems.

Also if for some reason you go to a t3 foot you can keep your t4 manifold and use a t3 to t4 adapter.

The only thing I see you having problems with is mpg, if you don't mind the mpg decrease I wouldn't worry about changing chargers.

I only have a 62 and my mpg can suffer.
 
i have the 62/71 .80 AR housing thats gated on my 12v but i think that is going to be too small for what the truck already has on it. if i can just get my mpg above 10-12 mpg i can deal with it for a while til i can either find another charger or do something different. the way it runs now is clean and puts out a haze to a little amount of smoke under moderate acceleration which is a lot better than before. i just filled up tonight so ill run this tank to see if there is a gain in mpg. might consider the billet wheel for this turbo or a smaller housing since that would be cheaper than a whole new turbo
 
I would like to suggest using a pulse adapter and a timing light Sanp-on pulse adapter. I am running .093 SS lines and a 180 HP pump. I set my plunger lift to 5.9mm (21 deg) and it is actually running at 15.8 deg according to the timing light (I had to make a TDC indicator on the balancer). With that being said I will go through my set up.
I am running a Schied street cam, SO pistons DDP250 injectors (never checked Pop pressure), 181 DV's, a flat fuel plate about 3/4 of the way back, heavy AFC spring, 3K gov springs, Steed speed billet manifold with T-4 flange and Turbonetics billet 64mm t-series and a midframe 88mm compounds. I live at 5300 ft and get 15.9 MPG around town and 19.7 MPG at 75-80 MPH and if I keep it at 70 MPH I have pulled off 22.3 MPG. There is very little smoke at any throttle position...at sea level it has a very light haze a wide open throttle...virtually no smoke.
I tried running stock injectors out of curiosity and they would make the same boost (set at 45-50psi) but ran like crap. They ran hot, very smoky, and horribly underpowered. I was able to pull off nearly the same fuel mileage. My truck is an 01 QCLB 4x4 6-spd with stock size tires and 3.55 gears.
 
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if someone had one for me to borrow i would check it but i cant see dropping that much coin just to use a few times. i am running this tank of fuel to see if the change in the pop off helped any. i talked to Chris at ED for a good while the other day and have come up with a few things that i need to check on this turbo. depending on the answers to his questions i might be looking to down grade once again turbos.
 
Turbonetics TQ said:
I would like to suggest using a pulse adapter and a timing light Sanp-on pulse adapter. I am running .093 SS lines and a 180 HP pump. I set my plunger lift to 5.9mm (21 deg) and it is actually running at 15.8 deg according to the timing light (I had to make a TDC indicator on the balancer). With that being said I will go through my set up.
I am running a Schied street cam, SO pistons DDP250 injectors (never checked Pop pressure), 181 DV's, a flat fuel plate about 3/4 of the way back, heavy AFC spring, 3K gov springs, Steed speed billet manifold with T-4 flange and Turbonetics billet 64mm t-series and a midframe 88mm compounds. I live at 5300 ft and get 15.9 MPG around town and 19.7 MPG at 75-80 MPH and if I keep it at 70 MPH I have pulled off 22.3 MPG. There is very little smoke at any throttle position...at sea level it has a very light haze a wide open throttle...virtually no smoke.
I tried running stock injectors out of curiosity and they would make the same boost (set at 45-50psi) but ran like crap. They ran hot, very smoky, and horribly underpowered. I was able to pull off nearly the same fuel mileage. My truck is an 01 QCLB 4x4 6-spd with stock size tires and 3.55 gears.
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What size turbines and a/r on those chargers?
 
Chevycummins said:
if someone had one for me to borrow i would check it but i cant see dropping that much coin just to use a few times. i am running this tank of fuel to see if the change in the pop off helped any. i talked to Chris at ED for a good while the other day and have come up with a few things that i need to check on this turbo. depending on the answers to his questions i might be looking to down grade once again turbos.
Click to expand...
You should def get more than 10-12mpg. I would guess 14-16mpg.
 
Turbonetics TQ said:
I would like to suggest using a pulse adapter and a timing light Sanp-on pulse adapter. I am running .093 SS lines and a 180 HP pump. I set my plunger lift to 5.9mm (21 deg) and it is actually running at 15.8 deg according to the timing light (I had to make a TDC indicator on the balancer). With that being said I will go through my set up.
I am running a Schied street cam, SO pistons DDP250 injectors (never checked Pop pressure), 181 DV's, a flat fuel plate about 3/4 of the way back, heavy AFC spring, 3K gov springs, Steed speed billet manifold with T-4 flange and Turbonetics billet 64mm t-series and a midframe 88mm compounds. I live at 5300 ft and get 15.9 MPG around town and 19.7 MPG at 75-80 MPH and if I keep it at 70 MPH I have pulled off 22.3 MPG. There is very little smoke at any throttle position...at sea level it has a very light haze a wide open throttle...virtually no smoke.
I tried running stock injectors out of curiosity and they would make the same boost (set at 45-50psi) but ran like crap. They ran hot, very smoky, and horribly underpowered. I was able to pull off nearly the same fuel mileage. My truck is an 01 QCLB 4x4 6-spd with stock size tires and 3.55 gears.
Click to expand...

Have you verified that your indicator and TDC marks are accurate? Every truck that I've set timing on and verified with my pulse adapter has been within a degree or two. What kind of light are you using that can be accurate to 0.1 of a degree?
 
I marked my balancer when I was building my engine and found TDC using a dial indicator.(.050" BTDC and .050" ATDC divided by 2 to try and compensate for piston dwell) I use a digital timing light with advance...not sure of the brand. I was shooting for 16 deg of timing and set the lift at 4.9mm and the truck just did not run very well...it would easily pop on a free rev and was horrible in the cold. I verified my timing by re-checking the lift and it was there at 4.9mm. I used the timing light and according to that it was 12.6 deg of timing...which is not enough. So I kept going up in lift untill I achieved my 15.8 deg. and that was close enough for me........and I was sick of setting the timing!

Bsmith: The second stage is a F1-65 65mm turbine wheel with a divided .70A/R and the first stage is a F1-89 89mm turbine wheel. I also am running a Turbonetics RG-45 wastegate off the manifold.
 
10-12? I was averaging 14-15 with that truck with the big turbo and low pop offs. That altitude must really be a killer. ~350 miles on about 25 gallons. Rock solid on a 700 mile round trip every week for 9 months.
 
Turbonetics TQ said:
I marked my balancer when I was building my engine and found TDC using a dial indicator.(.050" BTDC and .050" ATDC divided by 2 to try and compensate for piston dwell) I use a digital timing light with advance...not sure of the brand. I was shooting for 16 deg of timing and set the lift at 4.9mm and the truck just did not run very well...it would easily pop on a free rev and was horrible in the cold. I verified my timing by re-checking the lift and it was there at 4.9mm. I used the timing light and according to that it was 12.6 deg of timing...which is not enough. So I kept going up in lift untill I achieved my 15.8 deg. and that was close enough for me........and I was sick of setting the timing!

Bsmith: The second stage is a F1-65 65mm turbine wheel with a divided .70A/R and the first stage is a F1-89 89mm turbine wheel. I also am running a Turbonetics RG-45 wastegate off the manifold.
Click to expand...

You sure that pump is not a 215 or has a cam out of one because my carts show 4.9 lift on a 215 pump is about 12.5 deg. or close just asking
 
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