LBZ: Big single, higher altitude problems

Cknight199

New member
Aug 23, 2012
1,827
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Salt Lake City, Utah
Here is the other thing.

Last season I swapped the turbine housing from my s475 from a .9 t a 1.0 and right after the swap the truck started running like shit. Wouldn't ever build more than 25 psi, and the truck also backfired if I downshift into high rpm's (3500+) and then lay into the throttle. It would be like a dead pedal until 1/2 throttle and then it would POP and then smoke white, and then act normal after that.

When I free rev it too, it will do something similar. It will rev to 3300-3400 rpm and then start to lope almost. then if I lay into the throttle more to push higher rpm's it will start to pop again.

I pulled the injectors and had them tested (last season) and they came back way out of spec for my return rates. Now truck has new injectors and still does those things, but spools much better... It wouldn't even build boost from a stop for a boosted launch, now it does that no problem.
 

Cknight199

New member
Aug 23, 2012
1,827
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0
Salt Lake City, Utah
Bump for this.

Little update, i got the tuning dialed in to where it will clean up the fuel at WOT on my #1 tune. #2 gives quite a bit more power (200us more) and becomes slightly smokey. #3 has barely any more power (another 200us). #4 and #5 do nothing but smoke more.

I swapped my housing for a .9, but still cannot get ontop of the charger when launching. What I cannot figure out, is no matter what I launch at, tune I run, etc. it'll never run faster than 109-110 mph. meaning I am still not making any more power than before.

So... There are some upcoming races and swapping out my converter will take to long to long and I do not want to do it since it won't make me run any faster than my previous times.

If I stepped down to a smaller charger, that would allow me to spool, would my overall HP suffer? I just can't seem to figure out why the truck acts like i am out of air.

The other option... is to hook up the nitrous.. but I don't have a waste gate just yet and don't want to blow up a charger on the strip lol.
 

dirtymax36

2nd place is last
Apr 11, 2013
367
2
18
If you're wanting higher hp out of a s400 and still get on top of it quickly I've been seein a lot of s468/87/.9 chargers and even some .1 housing s468 chargers laying 820-850 down. Just an option though
 

Blackmax123

Member
Aug 2, 2014
683
1
18
central Pennsylvania
Sub'd for this..

My lmm is doing about the same thing. Long story short made 671 rwhp with stock appearing 2.5 danville vgt, truck blew up same ever thing just built motor and 15.5:1 ccompression made 635rwhp. Switched to a tct 2.5 s400 from mark and trucks making 675 rwhp. Now switched to big lbz injectors, truck spools way faster, but stI'll seems to be about the same hp even though I haven't made it to the dyno yet. Funny thing is I'm running a 1056 converter also. But I have a 1055-3d I wanna swap in.

Curious to see what fixes your issue though..