Ok, I'm working on a 5.3 swapped extreme s10, has an all stock 5.3 just ls6 cam, pushrods, duel valve spring's, has a log manifold front mount turbo, turbo is 78-75 on3 unit, trans is 80e with ptc 3200 converter and a 3.08 gear. Problem is it won't spool to save its own life, check out the video...


That's leaving at 2500 rpm foot brake, does not hit full boost till it shifts into second, note that it go's like 60mph in first gear.

Things iv done...
-tune is good, timing is 29 degrees at 0 boost and 21 at 10psi (e85)
-no leaks, pressure tested cold and hot side
-push rod lenth is .045
-waist gate stays closed
-open exhaust
-no air filter
-bypass air/air
-bov stays closed
-switched out turbo to 70/64, this helped slightly but no were near were it should be.

What am I missing? Only thing I can think of is cam timing, engine has no blow by.

 

Retard timing till the boost ramps in. Less timing=more heat=quicker spool time.

 

Cylinder pressure spools better then heat, were ever it would pull the hardest n/a is where it will spool the fastest. That's how we have always tuned them and have never had a problem

 

how fat are you running it when it's spooling?

 

No reason to retard timing


As for other part how is the log designed?
What size crossover?
Far better cams to light up with on a 5.3

 

What does your exhaust look like? Dump the downpipe out of the fender and it will spool great!

 

Am I the only one who thinks the 80e and 3.08 gear is the issue?

It sounds like its struggling to get up in the RPMs.

 

Naw, there's something else going on there. That is terribly slow spool.

How exactly is the hotside set up? Any flex pipe sections?

 

The z06 cam in a 5.3 is a pretty lazy cam... It's meant for high rpm power in a high compression 5.7. That likely has more to do with it than you think. You say building cylinder pressure helps build boost... That cam is bad at it. People run much much stronger in larger engines with less cam. The triple 12 being a great example.

In a 5.3 the z06 cam Id bet pulls to 6700 rpm. And it's just fairly lazy but carries power forever.

 

Yeah I love my triple 12 even in NA form. Pulls great all the way to 6400.