silver bullet on 12 valve

classic low timing stumble... at least based on my experiences with it... the problem is amplified by cold weather and by high elevation
 
Forrest Nearing said:
classic low timing stumble... at least based on my experiences with it... the problem is amplified by cold weather and by high elevation
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Ok. Right now I'm at 16 degrees on this 913 pump. The head is supposed to get done this weekend by tnt. I'm going to advance the timing to whatever Weston likes for my combination! Hopefully it will clear it up.
 
the bucking issue I have is, when I let it lug down some, like around 45mph with the converter locked. It will do it if I am just cruising along with little load, and it will do it when climbing ahill with more load. It will also do it when climbing a hill with a heavy gooseneck behind, lots of load. My truck never smokes white or gray, always black, only makes about 40Psi of boost, tops. I have checked all of the boost system, it's good. This bucking problem was here when I had a set of cheap 5x16's and is still around with a set of ddp comps. As far as the silver bullet goes, I'm looking at it as I have goals of more power than I have right now ~550-600 and I feel it could maybe cool better than my current turbo.
 
and just to clarify, when I say buck I mean a shake bad enough to rattle the dash, but when I stab the throttle it goes away.
 
Convertor shutter? You could tie the TV cable full forward and see if it does it or not. Mashing the pedal increases your line pressures also.
 
Willy91 said:
and just to clarify, when I say buck I mean a shake bad enough to rattle the dash, but when I stab the throttle it goes away.
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mine does that a bit from a 3rd to 4th shift in lock-up at bout 10psi, its kinda annoying. DDP injectors have a sharper/more narrow spray angle and can except more timing (still keeping fuel inside the piston bowl) as to where 370's spray like flower pattern. im weary about my high timing but what can i do? more fuel, less timing=fire in the manifold and turbo right? everytime i add fuel i have to bump the timing or else it runs cr appy and hot! im about to go to 30*. Now note one thing, if the pump has been off the truck and set up by a shop other than factory, i believe that all pumps are different, the way they are shimmed and such. the true way to do timing is spill port but that would cost me money.
 
I think what you guys are experiencing is just the jerkyness of the touchy govenor springs that move the rack so easily with a certain load under light throttle while in lock up. Prob does in more on back roads to cause of the bumps in the road. Just the nature of the beast if you wanna spin up high, just need an eggshell foot.

Brett
 
it is a combination of govenor spring bounce and timing IMO. I would say 20* timing and loosen the tension 1 click or so on each side. I need to up my timing too, this charger needs RPM's to really kick it so I think 22* or so would rip...
 
Forrest Nearing said:
are we talking very light throttle? what you're describing almost sounds like governor bounce
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yes Light throttle, I did notice that it got just a touch worse when I tightened my govener springs down. could someone please explain govener bounce to me?
 
dzlfarmboy said:
I think what you guys are experiencing is just the jerkyness of the touchy govenor springs that move the rack so easily with a certain load under light throttle while in lock up. Prob does in more on back roads to cause of the bumps in the road. Just the nature of the beast if you wanna spin up high, just need an eggshell foot.

Brett
Click to expand...

or a pair of $2 dual throttle return springs from the HELP section at your local auto parts store :)
 
as the weight starts to move it overshoots the target rpm, then it compensates by backing off, and overshoots, and then compensates by increasing. Etc, etc
Basically it is an unstable system that needs dampening. The fact is is doesn't help that when the truck takes off it tends to lift your foot, and then you try to push back, etc, etc.
 
I just got my truck back together, and have put about 140 miles on it so far. I love the Silver Bullet so far! ... I have no issues what so ever spooling it. Im running the following with it.
5"-6" Stacks
AFE Stage I
Custom Stage 3 Head (#60, studs, o-rings, and all the good stuff)
CFM Intake Horn
ATS Exhaust Mani
Silver Bullet (duh)
4k Kit
AFC Kit
20* Timing ... I want to bump it to 22*
Custom DVs & holders
Custom 5x18 injectors
Airdog 150 w/ 1/2" Lines
 
zstroken said:
as the weight starts to move it overshoots the target rpm, then it compensates by backing off, and overshoots, and then compensates by increasing. Etc, etc
Basically it is an unstable system that needs dampening. The fact is is doesn't help that when the truck takes off it tends to lift your foot, and then you try to push back, etc, etc.
Click to expand...

canthis cause any damage, or just an annoying problem?
 
SmokinDiesel96 said:
I just got my truck back together, and have put about 140 miles on it so far. I love the Silver Bullet so far! ... I have no issues what so ever spooling it. Im running the following with it.
5"-6" Stacks
AFE Stage I
Custom Stage 3 Head (#60, studs, o-rings, and all the good stuff)
CFM Intake Horn
ATS Exhaust Mani
Silver Bullet (duh)
4k Kit
AFC Kit
20* Timing ... I want to bump it to 22*
Custom DVs & holders
Custom 5x18 injectors
Airdog 150 w/ 1/2" Lines
Click to expand...

what kind of exhaust temps does this make? Boost presure?
 
I know mine would do it and I am saying it could break shafts.
 
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