Its a Turbo Smart 50mm gate. Now I need to build my 4L80, Swap it in, and get a good driveshaft before I let it past 10psi. One step at a time

 

ahhh come on man 18lbs. and stock driveshaft=win

 

Stock shaft, built 4L60, no slicks=trouble

 

yeah i know ill quit cluttering up ur thread with b.s.

give me a call when u get a chance i got some interesting news

 

Turbosmart and tial both good stuff. You can usually get to about double gate spring then usually have to go up on base to go higher. But guess you can get a bit more with some electronic controllers and mabye depending on hook up options.
So if current gate spring is opening that early would have to question if it was the spring you thought it was. Also maybe depends on where you take off boost reference.If you take it off turbo it might be say 8psi but then after going thru intercooler maybe it will drop to be 6psi in engine at guage for example.

 

I referenced Turbosmarts spring chart for spring selection and my balance line goes all the way to the intake manifold. I do not know why the gate is opening at 5.5 with a 10lbs sping in it, nor do I realy care, I will spring it up to get the pressure I want. As for boost controlers, I do not see the need in one until I get my 4L80 built with a transbrake, there I can see the need in a two step controler.

 

Here is the latest update.

I took the car to the track last Saturday. The DA was at best 6019 ft that day. My first passes were very bad. I did some tuning and by the 6th and 7th pass the car ran a best of 11.67 at 125mph. My 60 ft is **** (2.1 seconds), and it still has allot of lag. It starts pulling and building boost right before it shifts from first to second gear. I had to put all three springs (22# worth) in the wastage in order to get 12psi of boost. All and all I had a great day. I was pleased with the mph considering the car does not come on until 200-300 feet down the track. My 1/8 mile time was 7.7 at 99mph which is proof how terrible the car leaves the line.

I did some serious studying of the data logs and I see the stall is not letting the engine come up in rpm. The car starts to push threw the brakes at about 2500rpm and the convertor is only flashing to 3000-3200rpm. I have been running this convertor ever since 2004. When I first installed it, I popped the trans on the first day at the track. I had the trans built, but I reused the convertor because it was new. I might have hurt it then. From what I understand, if the sprag in the convertor is damaged or bad, it could make the stall tighten up. I pulled the trans last night and sent the convertor to Lubbock to be cut open, repaired if needed, and loosened up. I told them I want it to stall to 4400rpm. I also ordered a steel drive shaft (I still had the stocker in it). I will have everything back early next week and I will be putting the car back together. I plan on going back out to the track that Saturday to see if there is any improvement in the 60ft and the lag time.

I think my lag is caused from a combination of things, convertor not stalling past 3000rpm, not able to hold the car on the foot brake over 2600rpm, no 2 step to help with that, and possibly the I piping size being too large (3"). I think with the convertor alone the car should 60ft at least 1.7 seconds NA and if I can stall it up to 4000rpm I should be able to get the turbo spooled up to 3 or 4 pounds before launch. If I can get it to start spooling the turbo will spool up quick once launched. I think a 2 step will also help me get it to spool on the line. And the last thing I might change is the “I” pipe to a 2.250" or 2.5" to help speed up the exhaust velocity and help retain more heat in the exhaust.

I will be ordering my 4L80 parts within a month. I plan on getting a 4400 stall for it too. I will be getting a Rossler Transbrake and I plan on wiring up the 2 step to work with the transbrake. I am hoping with the transbrake, 4400 stall, and the 2 step I can leave the line with close to full boost. I am also going to get an electronic boost controller too, probably one that will let me set up a minimal and maximum boost setting and set up a ramp rate between the two. Once I have the boost controller on it I plan on turning the boost up to 17psi ish.

If none of this works, I am going to get a BMR turbo engine cradle, and the EBay hot parts kit and move this turbo up front. Surely if it is up front it will have close to zero lag. I really do not want to do that, but if I have to then I will.

 

You should see nice increase in boost off the line from even just the two step ,but a higher stall likely will help as well. And of course no pushing thru the brakes with trans brake.
Another option might be to run small shots of spray 75 to 100 would be a nice range to give nice spool. Course not 100% sure nitrous will instant spool a rear mount like it does a front.
As you said guess you can convert to front mount if you don't get things how you want them after trying some of this other stuff. You may still be able to get some gains with maybe playing with afr or timing preboost. Also isn't someone running some spooling up valve thing..Zombie mabye ? on his rearmount.Maybe that will help things out too.

 

Oh something must still be whacked if you need three springs to get to 22psi. The gate springs should be accurate. Tial gates are and never heard the turbosmart to be that bad.
I would still say if you have say a 22pound spring and are not boosting to 20psi at least then you have major boost leak, blown turbo,bad exhaust leak into turbo,blow off leaking bad, or some bad leak in there. LImit though is sometimes about double gate spring pressure. So 7 psi spring might not do much over 15psi then guy will usually upgrade to say 10psi to hit 20psi .with controller of course.Some controllers can push things a bit farther,talking electronic types.

The baby sts rear mount can hit like 12psi or more no problems on rear mount.
What did you say happens when you simply run no line to the gate?? Did you carefully check that I forgot too many different boards and threads.
If you unhook line from turbo to gate then get high boost you know its gate problem. Course you could also be losing pretty good boost if checking it at engine after its going thru the intercooler and all the piping maybe very inefficient intercooler or leaking intercooler???
Just throwing out a few more ideas for you.
Your problem should be making too much boost and having to limit it down not trying to get enough. Your turbo is pretty big isn't it..??
Also with eboost 2 you can ramp boost by rpm, which is like ati procharger type of power curve,set it up by time ..which i think would be great for track and ramp by gear with your auto as guy in other post is making me a little kit to make it simple to ramp my 4l80 by gear with my eboost 2. I think boost by gear is the best option for street use seconded by ramp by rpm.

And and for finding booost and vacuum leaks and exhaust leaks automotive smoke machines are hard to beat. Found many on my various turbo cars with one and found them super fast and you find leaks in many wierd unexpected places especially in my talons..injector seak into intake leaks,intake manifold gasket leak, exhaust manifold to turbo leaks, intercooler and piping leaks..etc.etc. Well worth checking on them if you have access to one.

 

The valve Zombie uses will not work with my turbo because they do not offer a tangent turbine housing for my turbo. I realy do not want to change everything to a front mount, but I really, really, will not put nitrous on it to make it work. I am determined to work out the bugs on this thing.

 

Hey neighbor! Is this turbo new? If not have you checked the turbine wheel just to make sure there isnt a big chunk taken out of it?

 

Yep, it is a new turbo. I will down your way again with it soon. I am from Odessa and still have allot of god friends there. I take it to DTR and Penwell all the time. I dought I will be at DTR until I get the hole shot and lag issues taken care off. You should think about coming up here and visiting our track some time. I think you would have a great time here.

 

Yeah im almost done with my car its a 2000 formula with a diy truck manifold front mount y2k80mm, glide, 9inch etc. Im just ready to get mine done so i can see what a real race car feels like!

 

I was having this problem and found out that I had a million pin hole leaks in the ex piping. (I didnt weld it). After that was fixed it hits boost like crazy, but same problem with the wastegate. No boost if its hooked up. It will hit annt boost you want ungated though. bad idea ha

 

The charge pipe size is not a concern when it comes to spooling really... The size increase is actually going to decrease flow resistance at low air speeds, and the volume increase is nearly in-measurable compared to the amount of air you are flowing through those pipes.

 

I have checked the exhaust and the charge air piping a few times. I think my exhaust piping is too large, causing the velocity of the exhaust to slow down, and the exhaust to cool too much, causing even velocity to drop even more. Once I am up making power the velocity is fast enough not to let the exhaust to cool off, so once on boost and making power the turbo spools right up. I think the convertor stall being incressed from 3000 to 4400 will help with the velocity and the spool time off the line. I might still need to reduce the "I" pipe size, I will wait and see what happens after I change the convertor and get a 2 step, or after I install the 4L80 with the brake, 2 step and 4400 stall.

 

My charge pipe sizing is 2.5" from the turbo to the intercooler, then 3 inch from the intercooler to the throttle body. My exhaust is stock manifolds going into 2.5" at deletes, then 2.5" SLP "Y" pipe, then 3" "I" pipe to the turbo. The "I" pipe is what I am thinking is too large, I think I need to reduce it to 2.5" or 2.25" in order to get the exhaust velocity up going to the turbo, if the other stuff does not fix the problem.

 

have you though about changing the hot housing on the turbo to a smaller AR?

 

Yes, I did change it from a garrett t-6 1.08 ar housing to a Precision Turbo t-4 .96 housing. That did help it allot, but not enough. I still think the main problem is not in the turbo or the setup. Changing to a smaller "I" pipe in the exhaust might help it, but I know my stall is way to tight. It will be back next week and I should be able to make it to the track next Saturday so I will know if the stall is the biggest problem or not.

 

Piping size won't change that much. I'm 3" exhaust and I/C piping. Stop thinking about velocity, you need to keep every bit of heat in the exhaust.

Even without the quick spool valve I run I could spool my 80mm 1.25 a/r 87mm turbine. Didn't spool very fast but was usable. Would be even better now with the exhaust changes that were made.