spool time s480
I'd focus on the tune since changing the hotside isn't an option.
Thread Starter
On The Tree
Joined: Feb 2019
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relying on compressor pressure for boost control ,
its hard to know what to expect from spooling up, from my data log u can see it barely makes any boost til 5000rpm. and this is not a 3 speed so that isnt very quick.
its hard to know what to expect from spooling up, from my data log u can see it barely makes any boost til 5000rpm. and this is not a 3 speed so that isnt very quick.
Thread Starter
On The Tree
Joined: Feb 2019
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Could it be the combination of the glide and 3.5 gear so it doesn't have the power to pull from down low and therefore spooling the turbo slow.
It built boost quicker in time With my 4.1 rear. But had more rpm
It built boost quicker in time With my 4.1 rear. But had more rpm
Thread Starter
On The Tree
Joined: Feb 2019
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haha , okay well good you think its not the trans.
ive had a 22psi spring in it to keep it closed tight and still no change
does that boost ramp look close and a tune get it a little better , or is something way off
its very hard to say without going in a similar car or something to compare to , especially when some people are sayung boost is instant or comes in real quick
ive had a 22psi spring in it to keep it closed tight and still no change
does that boost ramp look close and a tune get it a little better , or is something way off
its very hard to say without going in a similar car or something to compare to , especially when some people are sayung boost is instant or comes in real quick
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Something is very wrong. Ive seen s480 t6 spool on a 5.3 by 3500rpm. If it won't make boost below 5000rpm then you most likely have a leak somewhere either hotside or coldside. No way is that normal. I guess it could be tune related but it would have to be way off to make that turbo spool that slow in my opinion. Have you tested the hotside with a smoke machine. You can do the same thing with the cold side. Its crazy how much a small leak can cause a huge loss of boost.
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On The Tree
Joined: Feb 2019
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I am going to redo my hot side crossover as it doesn't sit how I like. One time I check it's sealed the next time I run air through and it has a small leak.
my converter flashes to 3600 so I can't see it making any positive pressure before that.
at 5000 I have about 6 or7psi.
it's a btrs2 cam.
226*231 113+4
could this be too much cam causing it to come in to late on a street car
my converter flashes to 3600 so I can't see it making any positive pressure before that.
at 5000 I have about 6 or7psi.
it's a btrs2 cam.
226*231 113+4
could this be too much cam causing it to come in to late on a street car
On The Tree
Joined: Jul 2011
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I am going to redo my hot side crossover as it doesn't sit how I like. One time I check it's sealed the next time I run air through and it has a small leak.
my converter flashes to 3600 so I can't see it making any positive pressure before that.
at 5000 I have about 6 or7psi.
it's a btrs2 cam.
226*231 113+4
could this be too much cam causing it to come in to late on a street car
my converter flashes to 3600 so I can't see it making any positive pressure before that.
at 5000 I have about 6 or7psi.
it's a btrs2 cam.
226*231 113+4
could this be too much cam causing it to come in to late on a street car
Thats the T4 S480 right? What intake? Somethings off IMO. My 4.8 StG2 summit cam made boost more quickly. Thats with the 1.32 T6. Are you talking about just stabbing it from a dead stop? Or on a trans brake?
May take a few steps back and test the basics. Cranking compression? Sync timing, etc...
May take a few steps back and test the basics. Cranking compression? Sync timing, etc...
Thread Starter
On The Tree
Joined: Feb 2019
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I am talking stabbing from a stop or slow cruise.
I think I might have a some leaking on the hot side going on.
I'm getting manifolds crossover fixed next few days probably just get the dump pipe modified to suit my s369. Maybe more suited to what I'm after anyway.
I think I might have a some leaking on the hot side going on.
I'm getting manifolds crossover fixed next few days probably just get the dump pipe modified to suit my s369. Maybe more suited to what I'm after anyway.
I'm sure that will be a night/day difference, but something is still wrong. Slapping a baby turbo on may make it better, but it shouldn't be as bad as it is now. I'd try to find whats wrong first personally.
If you don't find any big leaks on the hot or cold side, and its still slow to spool once leaned out... it has to be something mechanical I'd think. I Do agree though. Should be in the 12's w/ more aggressive timing until the turbo is lit. No reason to be down in the 10's on E with an intercooled setup at baby boost.
I swapped in a gen4 5.3 one year and power was down a ton, super sluggish to spool etc. Finally found the crank keyway was 8-9* retarded. (factory crank!) Cranking compression was horrible, down in the 140's. Degreed cam and cranking compression jumped up to 200! (JFR trip 12 cam) After that, the engine was literally snappy, just like your looking for. Would light the tires before boost came in. Picked up 12mph at the track at the same boost level. It was a mean little 5.3 combo. Trapped 159 at 24lbs with a S476. (untouched 799 heads).
If you don't find any big leaks on the hot or cold side, and its still slow to spool once leaned out... it has to be something mechanical I'd think. I Do agree though. Should be in the 12's w/ more aggressive timing until the turbo is lit. No reason to be down in the 10's on E with an intercooled setup at baby boost.
I swapped in a gen4 5.3 one year and power was down a ton, super sluggish to spool etc. Finally found the crank keyway was 8-9* retarded. (factory crank!) Cranking compression was horrible, down in the 140's. Degreed cam and cranking compression jumped up to 200! (JFR trip 12 cam) After that, the engine was literally snappy, just like your looking for. Would light the tires before boost came in. Picked up 12mph at the track at the same boost level. It was a mean little 5.3 combo. Trapped 159 at 24lbs with a S476. (untouched 799 heads).
Thread Starter
On The Tree
Joined: Feb 2019
Posts: 157
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I'll do a ComPressing test See what numbers it's getting.
I get the feeling the hot side leak is the problem, I think it's gotten worse since I first done a test on it.
is the 369 still gonna be a decent choice for a street car if I went with that one
I get the feeling the hot side leak is the problem, I think it's gotten worse since I first done a test on it.
is the 369 still gonna be a decent choice for a street car if I went with that one
Check any flex sections closely, I use copper RTV on all vbands/turbo flanges as well. If you get it all sealed up it should work much better. If your goal is truly 700hp an S369 may get you close but peak power is gonna be RPM limited and backpressure may limit timing as well. I ran twin S369's and they spooled faster then what you show for the single 80 so your problem isn't turbo size alone.