Texas_WS6

iTrader: (9)

Ok, I just finished checking for leaks, again. I did it a little diferent this time. I lifted the car up on my car lift (best thing I bought in a long time!), fired the engine up, got a friend to hold the plug on the exhaust tip, and rolled all over under the car feeling for leaks. None, no felt leaks, no leaks you can hear. Nothing. I do believe seeing as how this is the fourth or fith time I have checked for leaks, I do not have any leaks.

Texas_WS6

iTrader: (9)

The higher stall does seam to have hurt the lag time. The 4L60 does have a low first gear, maybe that with the 3.70 gear is not loading the engine. With those two gears together would explain why I can not hold the engine past 3000rpm before pushing threw the brakes. Maybe my whole problem is the stall, the first gear ratio, and the rear end gearing.

What stall, transmition (first gear ratio), and rear end gear is everyone running with the PT-88?

MY99TAWS6

iTrader: (3)

You are checking for exhaust leaks?. Can't check for boost leaks until car is under load nad building boost . Can only check by making boost leak tester sealing things up and putting compressed air thru with decent compressor.Or using an auto smoke machine.
I would think more likely you had a boost leak by fact you are gating up so high on the gate to get any decent boost number. Bypassing intercooler could be a good idea if its got a bad internal leak.I guess beating a dead horse here though if you are sure you have none.
Also 4400 does seem pretty high for a converter with boost ,seems most I see are like 3400 yank like mine. But haven't had that much experience with boosted autos to be an authority on that subject. And my car is front mount not rear.

Down low all you should need is that two step and maybe some 3.42 or 3.23s. Up top think you said its boosting good. Did you say you tried no line to gate at all to see what effect that has. Of course do this carefully to make sure you dont' go to 25 or 30psi.

Are there seals in the gate that could leak or be damaged.

Texas_WS6

iTrader: (9)

Ok, I am looking for exhaust leaks as to the cause of the slow spool, large lag. I have pluged and pressure tested the charge air side from the turbo inlet to the tb up to 13 psi. Anything above that and the plug shoots off.

There are no leaks on the cold or hot side. I have checked both sides at least four times each.

Texas_WS6

iTrader: (9)

Yes, I have pulled the sensing line and the boost climbs over 15, which is when I took my foot out of it. The gate I also checked when looking for leaks as well as the blow off valve.

Johnv

What exhaust/ muffler do you have after the turbo ?
A friend had similar issues, needed double the wastegate spring to make desired boost and was laggy (front mount).

He stepped his exhaust up a size and ditched the flowmaster muffler he had for a straight through muffler and suddenly he had full wastegate spring boost, and spooled up much quicker, infact he started getting boost creep and had to add a bigger gate.

Texas_WS6

iTrader: (9)

The exhaust sizing is as posted, notice no mention of mufflers, because there on none.

RooRnZ28

iTrader: (14)

Two things that stand out to me is the gearing and TCI stall. I think you should try something different in those areas.

I know when I went from 2.73's -> 3.25, my spool time in 1st was affected a little bit(little more laggy). Maybe try changing them out to something numerically lower than 3.70.

For the stall, i think you should look into a different one than the TCI. Is it still a single disk? Maybe look at something for a turbo car and made for your high power level.

good luck!

Texas_WS6

iTrader: (9)

Everyone please, I am frustrated enough as it is. I am 40 years old, not a kid here, I am a profesional mechanic, I work on machines making up to 4000hp at 1200rpm all day long, I am not an idiot. Please read the description of the car and built. I took the first three post to describe the build and describe the problem. PLEASE read these before asking me about the build. I am sorry but it is very frustrating to have to describe everything over and over again. I even posted the link to the other thread. It got too long do to too many people asking the same things over and over again.

I again appoligize for this tempor tamper, put yourself in my shoes and you will understand.

Thanks, I know you are trying to help and help is what I need right now. Just please read the first three posts before asking about the build.

MY99TAWS6

iTrader: (3)

Ok all good info. So yeah no idea why you said you need 22 psi spring to reach 12.5 boost. That makes zero sense what does turbosmart say about that. I have a 7.5psi spring in my tial and get about 7.5psi boost.

Now you should test in higher gear like third not first. So in third you only see 12.5 psi with those 22psi springs?

Anyway off the line is going to be fixed with two step, transbrake can't hurt .
4l80 has 2.48 first gear and 4l60 has 3.06 I think .So combined with 3.7 currently you do have more final ratio there in first .So 4l80 would knock it down. Then maybe some 3.42, 3.23 ,3.08.. would do better job. I would likley have gone to 3.42 or 3.23 if had the option on my rearend. A bit less rpm on highway would be fine too.

Also really not that bad to put a small shot of spray on there. Done all the time in the import world where they use big slow spooling turbos. Small shots are all thats needed like 75shot or 100 max. Heck even 50 might do the job. And they magnify the hp effects on FI .So 100 shot of spray might add more like 150 hp total.

I should maybe have went single nozzle style for simplicity on my car.Went direct port mostly for car show/hood open imtimidation reasons and the fast was made for direct port. But actually running small shots on direct port can clog nozzles easier as nozzle holes get very small as your shots get smaller over a single nozzle setup. I don't think will actually be using my spray much anyway as my smaller turbos spin up very quick. Would think have full boost in third at 3000rpm so maybe it will be 3300 with new bigger ones according to LG estimates.And would expect later spool up in the lower gears of course. Course when you get your downshift you will get boost really fast too.
Its going up thru the gear initially that the big turbo lag gets more annoying.

Texas_WS6

iTrader: (9)

Yes, I am starting to think my rear end gearing, stall speed, and first gear ratio is killing me. This is my first turbo build, I guess it is opposite of a NA build.

No the TCI is still single disk, I am thinking of going with a billet double disk from Square D (or circle D).

So you are saying switching the gears caused your lag time to increse?

Texas_WS6

iTrader: (9)

The spring pressure does not make any sense to me either, yes 22 psi of spring to make 12.5 psi at the manifolds, and the gate is sensing at the manifold. It reaches 12.5 as soone as it shifts into 2nd and holds steady all the way threw 3rd and forth to the finish line.

RooRnZ28

iTrader: (14)

I don't know how that tci has held the power for this long, but that would be one of the first areas to look at. The circle D triple disk is something I was looking at personally for my car, as my single disk can barely hold 500rwhp.

As for the gears, yes they did affect my spool time and I could really tell in 1st gear. 3.70s are pretty high.... I would think 3.50's max, as you don't see many turbo cars with numerically high gears.

Texas_WS6

iTrader: (9)

The TCI did have disk and sprag damage, and it ran all those years with the stock 346, MS3 cam, and lots and lots of 150 shot launches. The stock 10 bolt with 3.73 gears held up good too, until I installed the 408 last spring. It went toasted on the fith launch while tuning the car. Thats when it got the Moser 9" in its place. HA!

Texas_WS6

iTrader: (9)

Here is what I did to test this gearing idea. I took the car out and set the trans in 2nd gear. I used my HP Tuner to do this. I then tried to see how high I could stall it, and to see if it would spool up. With it in 2nd I was able to easily bring the throttle possition up to 36% I could hold the car at 3938 rpm. The turbo started spooling and buy 4900 rpm the manifold pressure was at 102kpa. Ofcourse the drag radials were smoken pretty good at the launch. At 5900 rpm the MAP was at 150 KPA. I never got over 95 % throttle.

What this says to me, and feel free to correct me here, what this test tells tells me it is not a turbo issue or piping issue, but a loading issue.

With that said, a 4L80 would help because of the first gear ratio as compaired to the 4L60's first gear. But with a transbrake, the first gear ratio nor the rear end ratio will matter. A transbrake will load the turbo and get it spooling.

Now the question becomes wich trans and why and wich rear end gear ratio and why. I am already running out of gear on the top end so the 3.70's are too steep. I will need to go down, probley alot. This will also help to load the turbo as well. But by going to the 4L80, the first gear will most likely be to much with the rear end gear ratio needed to stay out of 4th or to keep from locking the convertor.

I also can see with a transbrake there will not be a need for as much stall.

So now my question to you is wich trans should I get and why, and what rear end gear ratio to match it with?

mike13

iTrader: (27)

I've tried to keep up on this thread, have you varified that your waste gate spring/springs are actually the correct spring rate? Sorry if this has been addressed already. This seems like one of those type weird problems where something simple is just not making sense.

Texas_WS6

iTrader: (9)

The gate comes with a single 10 psi spring in it. I ordered the 7 and 5 psi spring for it. The gate can hold up to 3 springs, an outer, middle, and the inner spring. I double checked the spring pressure with the spring chart from Turbosmart. They are color coded. I personaly would not call that "verified". I also brought home a high dollar tool we use at work to set up valves like this. It is a special calibrated pump that can be used as pressure or vacuum to check the cracking and full open pressure. I checked the blow off valve and the gate with only the 10 psi spring in it. The gate took 9.? psi to crack the gate. It did open early. I did not use this to check the gate with all three springs in it. I just figured I would buy an electronic boost controler and dial up the pressure were I wanted it at, or I would order the 14 psi spring and just play with the springing until I achieved 17psi on the manifold.

Something I just thought of that might also be contributing to this spring issue. First, I installed the gate with the exhaust flow not having to make a turn before it hit the bottom of the valve, and second the gate dumps straight to atmosphere so it has not back pressure after the gate. Maybe those things combined is throwing things off like it is.

I have heard of people not getting the same manifold pressure as spring pressure.

topend

gears do not load the engine. The best thing u could do is move the turbo to the front.

Zombie

iTrader: (2)

If the WG cracked open at 9psi with a 10psi spring then it's not a 10psi spring. With a 10psi spring it shouldn't start cracking open until at least 20psi or higher since you have no exhaust pressure pushing against it. This varies with the size of the gate.

Are you blowing through the converter? If you just change to numerically lower gears you will only make problems worse if the converter isn't working right. You should be spooling faster not slower after having the converter loosened up.

With a 408 and a PT88, don't waste any more money on 4L60's, they won't hold the power. 4L80 or Th400 and a converter from a company that understands turbo setups. Having the right converter makes a world of difference.

MY99TAWS6

iTrader: (3)

Looked at turbomsmart instructions for gate as well. Maybe it has something to do with way you mounted it. Can't really see how you dump it mattering. I straight dump my 97 talon tial and it is dead on the springs.

You have no nipple on the turbo so are taking boost from way up front of the car???
Most times you take boost reference right off the turbos to the gates and run separate boost reference to the boost gauge or controller.
I was told that super long boost reference lines could even whack my alc injection if ran it to the back of the car for trunk mount system. I was told to mount controller closer to front so boost signal line would be much shorter.

Alll I know is it don't make any sense to have their springs that much out of whack.Have you contacted them by email yet??? You are compensating and sure you will get your
18 or whatever goal when you add in boost controller but really it should be close to rated.

But if you aren't worried why its whacked guess we aren't either.