Timing...explored.

ride42

ride42

980MW
Joined
Jan 1, 2007
Messages
4,506
There has to be some sort of way to find what the best degree of timing to set a pump to for a given set of fuel available from the pump. Being as I am still getting the bottom of my feet wet in this...any help? If there is an equation with the fuel available from the size of injectors and DVs that I can use to get the ultimate timing setting then let's hear it.

I have a set of 5x.014 injectors and .030" DVs. The truck is currently setup at 19°. I want to try it at 16° and also at 22° to see which might run better but I prefer it to not be a game of "well let's try this" so let's hear it.

I set it up using the timing pin method but want to try the drop valve method and see if I can get it a little bit more exact.
 
its a trade off

sounds like you have 145° injectors, right?

so as long as you dont go beyond 26° its just about where you want ur power

for operating range of 1800-2300 you only need 15°

the more you adv it the harder it will pull at a higher rpm

its just personal preference and dont really think there can be a chart for it

don

ps - once you have driven the truck with it at 23° or so i really doubt you are gonna like it any lower than that - the question is how much low end are you willing to give up for more up top?
 
Something I never understood was that the higher the timing you run the harder it is to spool your turbo/turbos right?

Well how do some of these pullers/drag racers get away with running 30-35* of timing and spool their turbos like theres no tomarrow!
 
9 LIVES said:
Something I never understood was that the higher the timing you run the harder it is to spool your turbo/turbos right?

Well how do some of these pullers/drag racers get away with running 30-35* of timing and spool their turbos like theres no tomarrow!
Click to expand...

Because we molest and rape the clutch like a dirty ho.:hehe:

Actually, my timing is at 30* but i have a schied stage 3 cam to help the air flow and litterally put it to the floor and when it starts popping off the gov spring limit, then start slipping the clutch. But hey maybe thats just me.

Tim
 
9 LIVES said:
Something I never understood was that the higher the timing you run the harder it is to spool your turbo/turbos right?

Well how do some of these pullers/drag racers get away with running 30-35* of timing and spool their turbos like theres no tomarrow!
Click to expand...

Building boost at the line!
 
That's where I am looking for more power is the top end. It's got plenty of grunt down low.
 
62mm/71mm/14cm on the turbo. I want to upgrade it to a 64mm compressor here shortly though. I have the 4k kit with 1 initial click and 4 after.
 
Just a guess but there's less energy to hit the turbine with with more advanced (higher) timing. From what I understand diesels inject alot of fuel after top dead center much more so than a gas motor so by rasing the timing you are taking away some of this fuel being injected atdc. In taking away some atdc fueling you are likely increasing the time between the flame going out in the cylinder and the exhaust valve opening essentially decreasing the pressure initially releasing from the cylinder during the beginning of exhaust opening. This is good for high rpms given the combustion event happens quickly and you need injection to start earlier to fit on the shorter window of high rpm combustion, but bad for low speed slower combustion spooling turbo yadda yadda.
 
I run my Silver64 (64/74/14) with Westons 5x.012" and 19* timing and it will pull to 3600, but its laggy.
Once it spools, it pulls like a freight train.

Ride42 When does you truck start to defuel?
I was playing around with my GSK awhile back, and when I set it up tight 1 initial with 6 hard clicks (just enough before the idle would hang up), It would pull till past the tach, but it started like crap.
Maybe give the GSK another click.
 
I think he is referring as to the timing effecting the spool up. I can get mine to 10psi a LOT quicker than he can. 2 different setups but the least of my worries is spool up. It spools a bit slower than the WH1C did.

As far as defuel...no I don't know when. I can mess with the GSK tomorrow and see if I can net anything.
 
ride42 said:
I think he is referring as to the timing effecting the spool up. I can get mine to 10psi a LOT quicker than he can. 2 different setups but the least of my worries is spool up. It spools a bit slower than the WH1C did.

As far as defuel...no I don't know when. I can mess with the GSK tomorrow and see if I can net anything.
Click to expand...

What does the truck free rev too? No load, just mash the pedal in park or neutral.
 
the timing on my 13mm is 26*, scheid street cam, k31, auto trans. last night at the pulls was the first time that i had left the line with 22lbs boost. spooled like no tomorrow too. i could have left with more boost, but that was the hardest i have ever left. tires were going just like i had side stepped a clutch
 
last year with stock cam n head and a 66mm charger, 6 x 18`s, with 20 degrees timing it was laggy as all get out but when it lit it lit hard

with my new Ve pump, I have 17 degrees initial, and 13 degrees dynamic according to my pump builder for a total of 30 degrees
With the Colt cam and my head work, my new 71mm charger will spool 15-17 lbs boost free rev at 3200 rpm and under load of any kind I have 8 psi just drivin around at 1600 or so rpm......
hit the go pedal and it is 50 psi boost like a lite switch

I like it - advance that is
 
You must log in or register to reply here.
Back
Top