my latest motor build with pictures..

While it won't fix your problem all the way most likely every time I have increased timing part throttle smoke has decreased. May be something to consider.
 
im going to do another retorque today, this will be number 5 or something so i hope it stops moving as i think it should. if so im going to bump the timing up to 26-27 so this should help with smoke like you said and i agree..
im going to try and make a pressure tester from the primary to the exhaust tip today also.. i dont think its leaking.
 
If I get mine back in time for the Redding even, I'll follow you up so you don't get a CHP on your tail. Of course I may have the same issue.:doh:
 
You may try switching to a stock cam before you do anything drastic.
 
TheBigNasty said:
So the pistons are 17.5:1 in stock form, then you cut in huge reliefs? What gasket are you running? I'm assuming standard 12v?

I'm going to say that is the nature of the beast. Not only did the reliefs lower your compression, they killed the in chamber swirl. Going to be smokey and lazy on the bottom end, but I bet it is killer when you finally open it up.
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I Agree if you then add a 20 over gasket to the mix the low end is not going to get better .
 
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Either I'm entirely blind or it hasn't been talked about. What's the wastegate doing? Could it be prematurely opening and not driving the secondary enough to light the primary? Sounds kinda like how lazy mine was.
 
well i did another retorque yesterday and got very little movement so i bumped the timing to 27.. and opened the vavle to the afc.. i also added a tailpipe turndown to at least put the smoke on the ground for the people that have to follow me..
its better. still smokey but i think with the smaller turbo or turbos it might be almost able to pull a trailer.. i guess we will see..
i understand you guys might think about cams but the cam i have worked in the past, really pistons and head are all that changed. i know thats a big change but its a big difference on how its now working compaired to how it did work.. i dont think its the cams wrong doing..
 
scat said:
Either I'm entirely blind or it hasn't been talked about. What's the wastegate doing? Could it be prematurely opening and not driving the secondary enough to light the primary? Sounds kinda like how lazy mine was.
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gates working fine and is set up like it was on the last motor. its working off the boost between stages opening at 20.. i made a bit more power yesterday having made about 35psi total boost.. still smokey..
 
I did some playing last night and was only able to get 40 45psi out of my truck but it ran very very good, cant tell you if it was smokey or not because it was dark out on the "closed course" I was on.
 
DEZLFREK said:
well i did another retorque yesterday and got very little movement so i bumped the timing to 27.. and opened the vavle to the afc.. i also added a tailpipe turndown to at least put the smoke on the ground for the people that have to follow me..
its better. still smokey but i think with the smaller turbo or turbos it might be almost able to pull a trailer.. i guess we will see..
i understand you guys might think about cams but the cam i have worked in the past, really pistons and head are all that changed. i know thats a big change but its a big difference on how its now working compaired to how it did work.. i dont think its the cams wrong doing..
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Know why a stock ls7 427" with a very tiny factory cam can pull hard to 7000rpm? Because the heads are very large in cross section and can flow lots of air. Now, in vice versa, when a class requires a certain cylinder head (stock ish) folks often cam up to increase high end power to make up for the power the head can't deliver in hi rpm due to small and or poor cross section. The large cam crutches this by holding the valves open much longer. Big cam and big head work in one area, to the moon alice! Point, if your cam worked with the previous head in the typical driving rpms that means little when comparing how it will work with a head with a larger cross section or different flow path etc. That is what folks are getting at. Try the easy stuff first, then move on to more slightly less easy things like a cam swap. Good luck!

Also, as others have stated, the compression drop (whatever it was) is likely not helping.
 
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im wondering if having the head decked the recomended .060 put the injectors to low with the thin washers?????
i did change pistons to commercial bowls and have the pump maxed out with the old dv's and maxed plate will put out 680.. now have 181's so i would imagine it dropped 20-30cc's at least..
if it is the cam what direction do you guys suggest??? i was told this cam should work fine.. remember its almost the same as the 188/220 but is 187/223 instead..
also im thinking about having the intake valve recessed back in the head to gain back around .020 and go back to the standard thickness head gasket.. i can tell you it did the same thing with the standard gasket before i started tuning all the low end smoke i could out of it..
im hoping that the 62 over an 82 will help things even more..
 
Unshrouding the valves was a bad move. Have the valves set back in. That will help some. I'm not fond of the cam due to the fact I have seen a issue in the past with valve to piston contact with that same cam.
 
i agree with having the valves protruding was not a good move..
i hadnt had any problems in the past by running more relief than was called for.. this time i did.
what do you think about the injector being to low? being i took .060 off the head for deshrouding and im currently running the thin washers on the injectors.. i wonder if they are to low now..
 
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