Will delivery valves help the bottom end?

I would put the timing about 18-19. The silver bullet is not a 4000 rpm charger, in my opinion. 19 degrees should get you some decent power up to 3600 or so.
 
1BADRAM said:
I been thinking about going with a set from DDP's, I think they called them .042"s. Anyone have a used set of these they want to get rid of?
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DDPs are .024s.
When I was talking to CDS they said thats what they would put in my pump. They said the 191s were "junk". Give them a call, they might have them for cheaper.
 
tony597fitter said:
DDPs are .024s.
When I was talking to CDS they said thats what they would put in my pump. They said the 191s were "junk". Give them a call, they might have them for cheaper.
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I really didnt see a power increase with the 191's from the 181's, maybe more smoke and heat. Edm'ed holders the same story, truck seems to run better after the DV's and holders, but the drag strip timer dont lie, and never had the truck on a dyno, a gave a dyno operator the dimensions of my rear slicks and rear end measurments and he said it would'nt fit on his dyno anyway?, it will fit a pretty wide tire like duals but the width of the axles are so much wider. Anyway, they have to move more fuel the shoulder is .030" rather than .087" , really: how much better could another .006" off the shoulder be. Not sure i buy it. And this is from someone who has ran Scheid "Full Cuts", boy they were nasty, smokey, and hot! Just my $.02
 
zstroken said:
I would put the timing about 18-19. The silver bullet is not a 4000 rpm charger, in my opinion. 19 degrees should get you some decent power up to 3600 or so.
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Bingo, 4000 is a T-4 sized turbo.

My timing is at 20 and it goes flat at 3800.

Jim
 
I may have to borrow a timing kit from someone and turn back to around 19*, it's currently at 22.5*.
 
Measure your damper, figure the circumference and then you will know the number of degrees per inch. Then adjust it accordingly.
 
sounds easy, but I think I would like to get the dial indicator and everything. I never really messed with the timing portion much.
 
Forrest Nearing said:
191's are for people with 94-95 pumps... only because 181's aren't commonly available
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I have tried both in mine. The 191's run quite a bit better... Id say 40hp difference. EGT's are hotter, but easily manageable. I like the 191's better myself. They really arent even much smokier. Just a heavier haze at WOT.

Im curious as to why people think 181's perform better than 191's?

Eric
 
Cummins Driver said:
I have tried both in mine. The 191's run quite a bit better... Id say 40hp difference. EGT's are hotter, but easily manageable. I like the 191's better myself. They really arent even much smokier. Just a heavier haze at WOT.

Im curious as to why people think 181's perform better than 191's?

Eric
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I prefer a bigger injector/smaller DV combo over a bigger DV/smaller injector combo... cleaner power, lower EGT's, etc.
 
Forrest Nearing said:
I prefer a bigger injector/smaller DV combo over a bigger DV/smaller injector combo... cleaner power, lower EGT's, etc.
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Whats the point of having big injectors if you dont supply them with the proper amount of fuel? Injectors are just pop off valves. They should be matched accordingly to the pump. Tim
 
ILLINOISRAM said:
Whats the point of having big injectors if you dont supply them with the proper amount of fuel? Injectors are just pop off valves. They should be matched accordingly to the pump. Tim
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he's got 215 injectors... he could make more power than he's making now with some nice injectors and 181's and have less EGT and smoke.

injectors have pop off valves in them, but they are also an orifice... if you can supply the necessary fuel with less duration, you'll have a cleaner burn

when you start getting buck nasty on the fuel, yes you need to go bigger to support monster injectors, but most street trucks at moderate power levels will run better with the smaller DV's and a bigger injector.
 
Forrest Nearing said:
he's got 215 injectors... he could make more power than he's making now with some nice injectors and 181's and have less EGT and smoke.

I agree with that. For my own curiosity, i just wanted to know why you thought that. I tried 181 dv's, 191 and didnt notice any difference between them except a loss in power from the full cuts. Yes they cleaner, but noticably less boost and power. The injectors are what determins the smoke and egt. The valves just increase whats available to them. To me, dv are just more or less turning the pump up since we dont have a fuel screw. Tim
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The way i see it, others have made 800+ on 181's, this is more than i make so 181's would be enough. Ive ran 6.8x's at 103+ with 181's and 6.7x's at the same mph with 191's. Sure if i ever decided to pour some real juice to it, it would prob. run better with the 191's due to thiers more fuel available. The 181's would near clean up with only a .52 jet and the 191's are still pretty smokey. To sum it up, if your under 700 hp or so theres prob. no reason to change D.V's power wise, if Nit. is used this is prob. where the bigger valves shine. HEAT is always been my issue, the full cuts would have ran the best with juice if i could have controled the temps, but that much fuel was a flat waste. Im thanking of going back to 181's for a couple passes next time out just to see the diff. again in power [times] vers. heat [egt's]. Like i said once before the clock at the track dont lie, its a better judge of power than the seat of the pants meter any day! Sorry......
Ryan
 
What kind of temps do you consider hot? You say that "that much fuel was a flat waste", maybe you need more air and that could have helped out your times. Everybodies setup is different.
 
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Forrest Nearing said:
I prefer a bigger injector/smaller DV combo over a bigger DV/smaller injector combo... cleaner power, lower EGT's, etc.
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I will agree with that. I dont really like laser cuts in anything but a pulling truck, and even then, sometimes they are too much. I do think for a street truck, bigger injectors are a better choice than laser cuts, but I think most standard DV's are alright as long as the shoulder isnt completely ground off of them like lasers.

I have some new era 370's. I wouldnt mind to try those with my 181's to see what the difference is in my setup now.
 
ILLINOISRAM said:
What kind of temps do you consider hot? You say that "that much fuel was a flat waste", maybe you need more air and that could have helped out your times. Everybodies setup is different.
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I bury a 0-2000* pyro every pass around the 500 feet mark or maybe sooner. I wished i could get it down to where others complain of being to hot, say 1700-1800. It would not surprise me that it gets 22-2300, Thats Hot in any ones book. And thats with 2 - 625ml nozzles of str8 water, and some nitrous on the hot side of a 16L Mack truck intercooler.
And yes with my 66mm turbo the Full Cuts was a huge waste of fuel, they would peg the pyro right out of the gate, and i would dump the throttle about half track to keep from burning it down, even then it would coast through in the low 7's. Most every thing has its place in the world, FC's place would be with some one that had BIG air and BIG water only. No just talking here for me im at the track with a diff. tune up every week trying to learn more, the hard way, but the fun way. Your right, everyones set up is differant.$.02
 
Well i sure dont know whats up with your setup, but on mine with a 500cc 215 pump, 18* timing full cuts, .120 lines and marine 300 injectors and a 2.8 hx50 with 17cm non wastegated housing, no water or drugs would only run 1750 -1800 degrees in a pull. That was on a back to back run even. It would normally only do about 1600 or so. I seen in one of your other post about gsk that you are not turning the rpms you want. Maybe something is wrong and causing these issues. I dont know and im not trying to be a dick but you put it on here that you are having trouble. I am not. Whats the differance, i dont know. Tim
 
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