If you are running this without efi live maybe you have a over boost code or something, i'm not that familiar with the LB7 tuning.
DIY twins/ build thread
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Yes it does and it gets tripped alot at least on my truck until I turned it off through EFI
P0234 is the code that you have to turn off.
Funny, I always thought that was what the PPE boost valve was for, to crank up the boost.
So the first turbo makes 30psi the second/stock turbo can add another 20-30psi on top of that because it's taking the first air like it had no pressure and adding some more pressure to it. It all makes sence now.
Funny, I always thought that was what the PPE boost valve was for, to crank up the boost.
So the first turbo makes 30psi the second/stock turbo can add another 20-30psi on top of that because it's taking the first air like it had no pressure and adding some more pressure to it. It all makes sence now.
on the lb7 internal waste gate you want to run a boost valve on it. you want the wastegate to open right away to send more air back ot the larger charger.
on my twins the codes/tuning that was manditory was , maf voltage table needed to be rescaled , all boost dtc's turned off ,and all maf dtc's turned off to not pop ocasional codes . more in the tune but that is just to get the maf cammanding fuel like it should and not pop mil lamps and go into limp mode . and as far as the waste gate you want the 2 chargers to be close to 50/50 on boost so if total boost is 40 psi then your big turbo should be pushing a minimum of 20 psi ,the internal wastge gate on the little charger will only slow it down so much , and does not give you ultimate boost control , but will get you close if it is not enough you can add a external gate or port for higher flow like i did.
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ya i'll play more with wastegate tuning etc once i get a bigger tune in it.... still on stock transmission with 214k on it it pulls hard though
i took a friend for a 20 mile ride and he has an 04 cummins with built tranny and smarty (140hp tune i believe) and he said my truck was faster.... cant believe that but everyone that rides in it thinks its faster than it should be
it pulls hard thoughi took a friend for a 20 mile ride and he has an 04 cummins with built tranny and smarty (140hp tune i believe) and he said my truck was faster.... cant believe that but everyone that rides in it thinks its faster than it should be
i did the same tuning wise to run in AZ but wanted some street/tow tunes with the maf functional still working on getting it perfected
you DO NOT want the boost valve on it. then you will overspeed the ihi and push less boost out of the big charger
i figured he ment a vavle set to open it earlier but it should have been specified . and no matter what is doen the 50/50 rule will always show you what needs to be done .
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what 50/50 rule? i was always told that the little charger should push less psi than the large one to decrease backpressure. more like a 60/40 ratio.
yes i totaly agree but its not always possible while using internal gates depending on the a/r of chargers ect 50/50 would be the min imop . with a stock s300 gate and my s480 i can run with the gate unsprung and wide open and still not quite hit 50/50 have not tested since i did the wastgate upgrades to the s300 .
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true- but out of my twins right now i make 25-30 psi out of the large charger, and a total boost of 45-51 psi into the intake after the intercooler.
the ihi has a decint size waste gate , a stock s300 only has 2 5/8" ports for the gate and a a/r of .80 , a stainless housing equipped from htt has 2 1" ports for the wastgate and a a/r .70 . i had my ports punched out to 13/16" wich is as much as the valve size will alow on stock housing . i will find out if it was enough. the htt housing is the best way to go if money allowed . and before the mods i was getting 23-25 psi out of my s480 at 55 psi boost at manifold . big benifit to the s300 over the ihi is i dont run the risk of running off its map till 45 psi or so .
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x2...
this truck definitely has some sort of blessing on it, I can vouch for it personally...it gets like 15mpg towing, 19mpg going 80mph on winter fuel, and the trans has never limped with the tune and towing.
dont ever get rid of it foster
ben
oops yep, sorry forgot to write not, i was thinking it in my head, somehow it didnt make it to the keyboard, haha