can a .020" over headgasket cuse more smoke

stovepipe

stovepipe

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I changed my headgasket with a .020" thicker gasket can the decompression cause more smoke? I have never had done this before so kinda new to how the truck should reach to the change. Everything else stayed the same but the head, it was decked before I got it and I decked it .010" to clean it up. I fire ringed the head then used 14mm H11 studs for clamping. The head had titanium seats and harden retainers. I put my 66/74/16 turbo back on but seems to smoke a little more than it did before. The pump is suppose to be a maxed out 215 (887) pump with full cuts and 5x16 sdx. just wanting to see if you guys think I have another problem or if this is normal.
 
Way normal that's alot of fuel and a big laggy turbo with an auto! Your probably paying more attention to it now. Is this a daily driver?
 
So since you surfaced the head .010 and added a .020 over gasket you are .010 taller than you were before, right? Then I'd have to ask what thickness washers you installed under those 5x16's? It shouldn't make a night/day difference but it could be somewhat of a difference if you haven't re-tuned it. Could have something to do with a fresh head flowing better. Did you notice any difference in boost numbers?
 
Injectors will be .010 further from the piston, but still have the increase of cyl volume of .020
 
I went back and pulled my comp ratio calculator and a .020 over gasket will lower the ratio from 17:1 to 15.8:1 so roughly a point on everything stock but a .020 over gasket. ive gotten different numbers from different calulators but it is close
 
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dangerous06 said:
Way normal that's alot of fuel and a big laggy turbo with an auto! Your probably paying more attention to it now. Is this a daily driver?
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yes it a daily, I have tuned it the best I could with what I have the turbo is laggy and makes 60psi right now

Bullrack said:
So since you surfaced the head .010 and added a .020 over gasket you are .010 taller than you were before, right? Then I'd have to ask what thickness washers you installed under those 5x16's? It shouldn't make a night/day difference but it could be somewhat of a difference if you haven't re-tuned it. Could have something to do with a fresh head flowing better. Did you notice any difference in boost numbers?
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well when I went to put the other turbo on I noticed that the waste gate was a little lose or not shut all the way (I was not using the gate) so I made a couple of plugs and welded the housing shut because he shaft was siezed and I almost had to destroy the shaft that holds the waste gate covers to get it free. I see 60psi now but I am not trying to go over that were before I would see 50psi at full throttle. I am running stock thickness washers or what came with my injectors. not knowing what the previous guy took off the head the injectors maybe closer. If that guy took off .010" and I took off .010" then the injectors should be in stock location but the surface of the head would be .020" farther.

DISTURBED said:
I went back and pulled my comp ratio calculator and a .020 over gasket will lower the ratio from 17:1 to 15.8:1 so roughly a point on everything stock but a .020 over gasket. ive gotten different numbers from different calulators but it is close
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thanks I think that would make a difference now I have to make it up with turbo boost right. I had a H2E over a HT4C that is what took my gasket out around 80psi. I chickened out and went back to my single.
 
you try some different dv's if you want to loose some of that smoke and make some more power...
 
Competition style delivery valves in place of those full cuts. I am running 7mm comps and they are the best delivery valve i've run with these 5x20s as far as street/strip manners. The smaller 5x16s may be a bit more tolerant of the larger slightly better flowing 8mm comps. The 8mm version gives up some "crispness" at part throttle however. I would not expect the combination you have to be smoke free at all that is not a quick spooling charger on a 12v.
 
the pump came with full cuts in it I was thinking of putting the 180 DV in this pump but I am not sure if they would work. So a set of those comp DV would be better all around.
 
In my opinion yes. You will likely find opinions may vary.
 
most people that tune there trucks for most power and least smoke dont use full cuts unless its intended use is with nos.. most use a 181, 191, 024, 022, or some sort of modded 131's... any of these will smoke less and almost always give you more power than full cuts..
 
so full cut are only good if your running nos because of the amount of fuel that is dumped rather than a more controlled flow of fuel like a 181.
 
Nos or tons of air to burn the fuel. Full cuts are only good in competition only situations due to their driveability issues is more like it. Now, there are delivery valves (competition delivery valves) which flow as much as full cuts but drive as good as 181s except for some lope which some trucks have and others do not.
 
So these comp dv's aren't good with nitrous? I've got full cuts now and am trying to cool it off. Hoping that changing dv's would. But I am spraying alot
 
SCHOOL BUS said:
So these comp dv's aren't good with nitrous? I've got full cuts now and am trying to cool it off. Hoping that changing dv's would. But I am spraying alot
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No, they are very good with nitrous from what I understand. Given they fuel near identical to full cuts not sure if they will help your particular wot temperatures though.
 
I bought my truck used and it was always laggy and crappy on the bottom, it smoked more than any other vp truck in stock form.. a few months ago i put studs in and while i was at it i put a head gasket on it because it was leaking oil, the old gasket that came out was .013 thicker than the cummins replacement. With the new gasket its definitely cleaner and has more balls on the bottom. Just what i noticed from my experiences
 
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