Texas_WS6

iTrader: (9)

I am starting fresh with this thread. The old thread https://ls1tech.com/forums/showthrea...ferrerid=13507 was getting too long (8 pages) plus there have been a few changes to the car since the begining of the thread.

Here is were I am at now. Car is,

2002 WS6 4000lbs with driver
408 iron block
L92 ported heads
LS3 Intake (not ported)
Fast 92mm throttle body
Eagle crank shaft and rods
Ross pistons -12 reverse dome
Virgina Speed VTC-3 cam installed 105 intake center line
80# Seimens injectors
Aeromotive Boost Reference Fuel Pressure Regulator
Dual intanke GS340SS fuel pumps
4400 custom stall (TCI 3600 lossened up by Advanced Torque Convertors)
Built 4L60E
Moser 9" 3.70 gears
All tuning done by ED (Virgina Speed) and I with HP Tuners
Speed Density Open Loop tune

Now for the turbo build:
Rear mounted PT-88 .96 AR turbine housing (So the compressor wheel is a GT-47 and the turbine wheel is a 3RD-94mm)
50mm Turbosmart Racegate sensing intake manifold PSI
50mm Turbosmart Raceport sensing intake manifold PSI
AEM Methonal kit
Front mount intercooler
Stock 02 LS1 exhaust manifolds
2.5" cat deletes
2.5" SLP "Y" pipe
3" mandrel bent "I" pipe all the way to the turbine inlet
Header heat wrap from exhaust manifolds all the way to the turbine housing inlet. Single wrapped.
Charge piping is 2.5" mandrel bent from the compressor outlet to the intercooler inlet, then 3" mandrel bent from intercooler outlet to the throttle body.
Oil scavenger pump returns oil to the top of the Moroso oil pan.

Fuel system set up for 1200hp.

speedcrazy2

iTrader: (1)

put the juice back on it

Texas_WS6

iTrader: (9)

OK, I have been having a terrible lag issue. I first had a GM single plane EFI intake and a low profile Edelbrock elbow on top. Took it off and put the stock LS3 intake hoping it would help build low end power and help reduce the lag time. That did not help.

I had a 230/240 114 cam in it, swapped it out for a VTC-3 cam, that made the car drive way better, and it made the car pull like a beast under boost, but it did not help reduce the lag time. Cam swap was a very possitive thing.

I had a 1.08 AR turbine housing on the turbo, swapped it out for a .96 AR housing, that did help reduce the lag, but not all that much.

I thought I had a limited boost issue, figured that out. I had 10 psi springs in the racegate and it would limit the turbo to 5.5 psi. I now have 22 psi springs in it and it now limits the turbo to 12 psi. I am going to put an electronic boost controler on it next. My goal is 17 psi.

I now have my timing up to 30 degrees under no boost (WOT) and the timing drops to 22 degrees once under boost (planing on going as high as 38 degrees under boost). I run VP-113 fuel all the time.

My AFR is about 12.5 (no boost) and goes to 11.2 under boost.

I have checked, double checked, and I am going to check again today for leaks on in the system.

I could only stall up to about 2500 rpm before the engine pushed threw the foot brake so I pulled the convertor and sent it off to have it loosened up. They found the sprag was damaged and the clutch disk was in bad shape (I have been running this convertor since 2004). So they replaced the disk and sprag and layed the fins over some to loosen up the stall. Now it will stall up to 3100 before pushing threw the brakes and flashes pretty high. Now the rpm never drops below 5800 rpm (at WOT) after a gear shift.

The car still will not reach max boost in first gear. It will not make more then atmospheric pressure until right before it shifts into 2nd gear.

I am going to pull this trans out and send it to Finish Line Transmition and have them upgrade it to a level 7 and install a Rossler TransBrake. Maybe it will build boost before I launch with the transbrake.

Short of moving the turbo up front or puting nitrous on it what else can I do? They do not offer a split style turbine housing so putting a turbo valve on it is out of the question. I do plan on putting a 2-step on it too.

I first had a PT-76GTS for this build. I was talked into selling it and going to this larger turbo. I now think I would have been better off with the smaller turbo!

Texas_WS6

iTrader: (9)

Here are my times slips. You can see how big a pig this thing is out of the hole.

60 ft is in the 1.9 to 2.1 range
1/8 mile et is in the 7.7-7.8 range
1/4 mile et is in the 11.67-11.9 range
1/4 mile mph is in the 124-126 range

You can see this thing is a pig out of the hole but once under boost it screams its *** off. It basical is running the first 1/8th NA and then the last 1/8 under boost. I know alot of you are going to say that even NA a 408 will run better then that. Please take this into consideration, our alltidue is 3500 feet and a DA of 6000 feet is a great day, DA's of 7000+ is normal here. Usually the air pressure is about 83-85 kpa. Most of the built LSx cars around here run high 12's to high 11's NA with no power adder.

I do think this thing should be running better out of the hole then it does though.

Texas_WS6

iTrader: (9)

So were did I go wrong? What do I need to do to get this thing working right?

MY99TAWS6

iTrader: (3)

Did you say you have a two step. Much easier to build boost with a two step even with an auto. Stall is important too of course but just stall without two step isn't going to help that much. transbrake will let you hold the car better too so with two step it could also be a good thing. Ling or msd 2 steps work great and are plug and play pretty much.
Still have ling lnc 002 for sale. Got msd nearly new really cheap so using it instead but
the ling has more features,can retard for nitrous,can do antilag for manual cars.I would have kept it if stayed m6o or was going to run bigger shots.

Nitrous small shot is viable option. Your turbo is too big if you don't like the lag and you have already dropped ratio a bit. I guess maybe you could drop ratio way down not sure if they offer way lower but then might really hurt top end.

This is big reason two smaller turbos are better generally than one big one.
My problem is too fast spool up. Going to bit bigger LG and they will increase spool up slightly.

You may never see full boost in first. that is pretty common. Maybe going down some gear ratio will help out there more time in first gear.

If its mostly lag on launch you are complaining about as said get a two step and you should be able to launch good. If lag bugs you too much choices are smaller turbo, small shot of nitrous,bigger cubic inch engine. two smaller turbos go to twin setup. Front mount might help a bit too. Would think no matter what the sts setups will have more lag than a frontmount .But lag can be good for traction reasons.

You have played with tune as well. Not sure but lowering timing way down might help in the right before boost area. you can try that. M6 cars use antilag but dont' think it works too good on auto cars.

HUNTER02SS

iTrader: (24)

You probably will not build any boost in 1st. gear. The gear is to short and not enough load placed on the car to spool the turbo. On our T/A if I was footbrake and left the line, I would not build any boost until just before I shifted into second.You are going to need a transbrake and a 2 step to build anyboost off the line. Also would not suggest going to 38deg. of timing under boost either.

MY99TAWS6

iTrader: (3)

And again can't understand whats wrong with the gate springs why you need to go so high to get the boost up.

My tial springs are pretty much dead on. Unless as said you are have line right from gate to turbo nipple and you are losing massive boost thru intercooler and piping and therefore by time you read it at intake its way lower. I use just gates no boost controller is hooked up for control, I monitor boost at intake and its very very close to rated gate spring. I thought turbosmart was good stuff.I use their blow offs. If turbosmart gate springs are that much off I wouldn't use their gates for all the tea in china. You need accurate stuff. Thats why keep thinking some kind of boost leak is slowing your spool bad and making you have to get bigger springs.
you can have problem with exhaust not letting turbo spin up or in cold side piping, leaking intercooler, blow off,intake manifold,etc.
An automotive smoke test is very useful tool .If you can get access to one its found leaks on my various turbo cars very quickly and in very strange unexpected places.

If its not boost leak and you have two step then its time to make more hardware changes, smaller turbo, small shots of spray ,possibly lower numerical gears.
Did you say you can get 20psi if you unhook gate and watch boost? If you can get 20psi with no line to gate but not with it hooked up gate must be leaking bad if the springs are correct. Maybe you should get a tail gate on there. I have seen several sts with stock tial gates. I have tial on my 99TT ,on my 97 talon, and have not seen a tial not put out close to its rated springs pressure. Now normally you can't go much past double spring without electronic boost controller.

Zombie

iTrader: (2)

If you don't solve the real spooling issue before doing things like new transmissions, trans brake and 2 steps, you'll just be putting band aid's on a hatchet wound.

Did you ever check your exhaust manifold gaskets?

Longrange4u has a pt88 spooling just fine.

MY99TAWS6

iTrader: (3)

I say copy Zombie! And obviously he has his setup working good. Nice 60ft and great times both et and mph.

Texas_WS6

iTrader: (9)

I did not pull the manifolds off but I have sealed the exhaust side and pressure tested the exhaust side to 12 psi. I have also been looking for any exhaust stains that should form from a leak on the heads top and bottom. I can not find any signs of leaking manifolds. I am using the factory steal exhaust gaskets right now.

Texas_WS6

iTrader: (9)

I think going to the looser stall has hurt my spool time some. You might be on to something with the gearing. I am now going into 4th way too soon, switching to a 3.2 gear mght be helpfull.

MY99TAWS6

iTrader: (3)

Are you running old stock cats? Do you have a two step?

Texas_WS6

iTrader: (9)

When it builds boost it comes up very fast. I am no longer having a problem reaching my boost pressure, its the time it takes to get this thing to start spooling in the first place that is a killer.

I want this car to leave the line already under boost, even if it is only 5 psi of boost, but preferably with close to max boost.

I will be checking for leaks again today.

Texas_WS6

iTrader: (9)

Cats are removed, and I do not have a 2 step yet. Going to order the MSD one today.

Professor_speed

iTrader: (8)

If there are no leaks the thing that stands out to me are, 4l60 <-stupid low first gear, 3.70 gears also pretty low, and a converter that is not known for being tight to begin with, being loosened more. You said it got worse after the converter was loosened right? My guess is that you don't have enough load on the car. How fast does it spool in second and third if you roll into the throttle? When staging it you rev to a specific rpm? or until you over power the brakes? (you don't have a trans brake right?)

MY99TAWS6

iTrader: (3)

OK...try out that two step should help a lot.Mine activates off the brake pedal and putting a master on/off also as well shortly.
You should get some boost for sure with the two step and transbrakes are handy if you are going to track alot,I skipped it as my car is not going to get tracked much after they kick it off for no rollcage.
I still think you have other issues from what you say about the gate springs.
And do agree in your case some lower gearing 3.42,3.23 would be some help.

I don't like to go too low as hate the feeling of really low numerical gears off boost and around town most of the time my car is not into much if any boost.
And 3.54 is lowest numerical they offer on the strange dana 60.

Texas_WS6

iTrader: (9)

Correct, I try and bring the rpm up until it pushes threw the brakes and I try to hold it there. It only takes about 18-20% throttle to do this.

I have been thinking about the low first in the 4L60. I have two 4l80's, my plan was to build one of them with a brake, but the cost to get it in the car is about 2 grand more then just getting the 4L60 level 7 with a brake. The cost of another convertor, wiring harness addapter, trans cross member, shortening the drive shaft, massaging the car to make it fit, and last but not least, segmenting the tune and praying for it to work with the PCM.

I have nor ruled out going with the 4L80 but it would be nice to make all this work with a level 7 4l60.

When driving it around and stomping on it, it does not seam to take any time at all to spool it up, say if it kickes down into second or third.

I wish I knew which way to go with the trans, 4l60 or 4l80.

MY99TAWS6

iTrader: (3)

With your big turbo and bigger engine and sounds like you want to be pushing it near its limilts would go built 4l80 spend the money once and be done.
Swap was pretty simple ,simpler yet in an auto car. I just accumulated parts here and there for a few months and then swapped it in.
Yes you need crossmember,with torque arm relocation or tunnel mount torque arm.
Lokar 36 inch dipstick, I used flexplate from speed inc,tci has one as well.I did get 4l80 converter from yank their turbo converter that many fast cars on here use.
Not sure what you mean about controlling it with ecu. simple hptuners segment swap and you are up and running. Wiring adapter from 4l60 to 4l80 is simple little one as well.
And of course you don't need to do bunch of crap to floor like i did or find auto pedals ,autoconsole or autoshifter like I did.
For install you simply get ears cut off the 4l80.RPM cut them off as they knew it was an f body swap. You do some cutting and stuff around where the big fat plug is on the drivers side and you can notch were trans cooling fitting go ,we went to 90 degree an and just added on that extension tube like the stock return fitting has on the newer 4l80s.
I would say this swap was still very easy and straightforward. Zero regrets and pretty confident my RPM should take whatever I decide to throw at it.

For 500 to 600 rwhp maybe would stick with built 4l60.

cjmatt

iTrader: (4)

does it spool better once the converter locks up? seems like a high stall for boost, you need to load the engine