Auto launch issues

[blktalon3]

How long are you sitting on the converter before you let off? Also do you have a stock exhaust?

 

[Bud92gsx]

This thread is depressing..It makes me want a turbo that works..And also makes me want to go outside at midnight and try to spool a junk turbo..

 

[camfast]

If you have a stock downpipe or converter it could be that it has collapsed. A buddy of mine was having the same issues and could not figure it out until he changed the exhaust. It was a result of a collapsed downpipe. Just an idea...

 

[91stocker]

How long are you sitting on the converter before you let off? Also do you have a stock exhaust?

I let it go as long as 10 seconds in hopes it would get over the hump.

And yes stock exhaust minus the cat. I also cut out the little half cup in the flange and hogged it out to try and match the ported o2. It doesnt but its better then it was.

If you have a stock downpipe or converter it could be that it has collapsed. A buddy of mine was having the same issues and could not figure it out until he changed the exhaust. It was a result of a collapsed downpipe. Just an idea...

Collapsed? Is there an internal sleeve or something in the factory exhaust? It visually checks out from the outside.

A bone stock car can spool on the brakes right? Wouldn't think stock exhaust would effect it that much.

 

[camfast]

Youre going to need an exhaust system anyway so just get a punishment or megan dp. Yes, the inside was collapsed causing the choke but could still build some boost at cruising speed. If you have everything else cover as far as boost leaks etc.. then try changing the dp. Hope this helps

 

[91stocker]

Well my laptop battery died, only works when plugged in. So getting a replacement before anymore testing.

 

[jrohner]

I launch my 16g auto car at over 20psi on the 3750 2-step; that's the highest rpm I can hold it back with pushing on the brakes as hard as possible.

The biggest thing is getting cool air. Do not let the air filter suck hot under-hood air. I could brake boost for 10-15 seconds and not make any boost until I fixed my air intake (my filter is now where the sidemount intercooler was). The next most important thing was not having the AFR's rich at all, as well as having the timing high enough so you make a decent amount of torque. I run no exhaust, just a short pipe straight down off the o2 housing, which also helps I'm sure.

 

[91stocker]

The biggest thing is getting cool air. Do not let the air filter suck hot under-hood air. I could brake boost for 10-15 seconds and not make any boost until I fixed my air intake (my filter is now where the sidemount intercooler was).

I have the standard style intake pipe, but i still have the stock heat shields on. When i tried tonight the temperature was 49*. Doesnt seem like the intake air could be hot enough to effect spool up under those conditions does it?

The next most important thing was not having the AFR's rich at all, as well as having the timing high enough so you make a decent amount of torque. I run no exhaust, just a short pipe straight down off the o2 housing, which also helps I'm sure.

Yep, 11.5 ish afr's, 22*timing while on the stall. Stock exhaust, no cat.


Btw, as suggested i rechecked base timing. Set to 5*, i played with base timing with no setting allowing me to build boost on the stall.

 

[blktalon3]

I had a stock converter and a 14b and I was stalling around 8-9 seconds, if I remember right. I had a 3" turbo back exhaust with no cat though which probably helped a little. The stock flex section is a pretty big restriction. It necks down to under 2" I believe. I also second the wastegate theory, make sure the accuator is putting pressure on the wastegate when its closed.

 

[-red97rum-]

You know I was thinking of telling you to check your boost controller. Your sure the arm on the WG actuator is holding the flapper all the way shut? Does the turbo spool fast like a 14b should when you're out driving the car. This is bugging the crap outta me. Especially since I'm able to spool my hx35 in about 8-9 seconds with a motor that has next to nothing for compression at this point. Albeit, my converter is restalled. But from what I've seen you shouldn't have a problem building boost on a 14b with a stock converter. Does it knock at all when you're trying to stall it up? I remember you sent me a log a while back and I was tripping out because it looked perfect.. but the thing wouldn't build boost.

 

[GDNF2ET]

Doesnt seem like the intake air could be hot enough to effect spool up under those conditions does it?

I don't believe that under hood temps effect low end torque...My car brake boost the same whether the outside temp 105° or 30°, or if I've been driving my car for 5 minutes or 3 straight hours....
The parts you have that are unnecessarily ported for an auto/14b car are whats doing you in I believe. Porting kills velocity and hurts low end torque..That exhaust housing is the 1st thing I would change...
I'm looking forward to you finding a solution..Do you have any local dsm friends that will switch some parts around with you ?

 

[Bud92gsx]

I don't think it's the manifold tho..I can spool a 16g on a manual manifold, and 7cm turbine housing..

I think I should have the same issue should I not..

 

[GDNF2ET]

I don't think it's the manifold tho..I can spool a 16g on a manual manifold, and 7cm turbine housing..

I think I should have the same issue should I not..

Most people who port parts do more harm than good..There is a thin line between making a part flow better and ruining it entirely..He specifically says he has a ported 2g manifold and a ported 7cm turbo housing now..

 

[91stocker]

You know I was thinking of telling you to check your boost controller. Your sure the arm on the WG actuator is holding the flapper all the way shut? Does the turbo spool fast like a 14b should when you're out driving the car.

It really should be. I have it shimmed with two washers. When i changed to a 7cm housing the actuator felt very strong. Hard to pull back out. And yep spools nice after i left of the brakes. Full boost 3500'ish.

This is bugging the crap outta me. Does it knock at all when you're trying to stall it up? I remember you sent me a log a while back and I was tripping out because it looked perfect.. but the thing wouldn't build boost.

You and me both haha. Im still messing with it ever since i sent you that log. Everything looks spot on.No knock at all. Has new knock sensor also.

The parts you have that are unnecessarily ported for an auto/14b car are whats doing you in I believe. Porting kills velocity and hurts low end torque..That exhaust housing is the 1st thing I would change...
I'm looking forward to you finding a solution..Do you have any local dsm friends that will switch some parts around with you ?

I still have my unported 6cm housing i could swap back on. But i had the same issue before i swapped the new parts on. I was hoping to fix my problem and let it breathe a little better all in one shot. But hasnt seemed to work out that ###.

He specifically says he has a ported 2g manifold and a ported 7cm turbo housing now..

Those parts were ported by FP. I ported the o2 housing myself, but thats only gasket matched.


Also as suggested ive tried wg pressure and still no change.

 

[GDNF2ET]

1.You mentioned a NEW throttlebody..What is it ?
2.This car has non-adjustable cam gears correct ?
3.If the exhaust is in question, you can disconnect the downpipe and let it hang outa the way and try brake-boosting..
4.Next time you check for boost leaks, open the throttlebody by hand to see if the intake or injectors are leaking air
5.Would still like a pic of engine bay...
6. Has a compression test ever been done ?
We are gonna beat this problem d^mmit !!

 

[Bud92gsx]

Most people who port parts do more harm than good..There is a thin line between making a part flow better and ruining it entirely..He specifically says he has a ported 2g manifold and a ported 7cm turbo housing now..

So it's possible that the porting actually hurt velocity going into the turbo..And could be causing the non spool while brake boosting effect..But Won't hurt spool while driving around..

 

[91stocker]

1.You mentioned a NEW throttlebody..What is it ?
2.This car has non-adjustable cam gears correct ?
3.If the exhaust is in question, you can disconnect the downpipe and let it hang outa the way and try brake-boosting..
4.Next time you check for boost leaks, open the throttlebody by hand to see if the intake or injectors are leaking air
5.Would still like a pic of engine bay...
6. Has a compression test ever been done ?
We are gonna beat this problem d^mmit !!

1. Sorry if i worded it wrong, i have new tb gaskets on rebuilt stock tb.
2. Yes, stock cam gears.
3. I unhooked the downpipe and no change. Still only made 3psi after 10 seconds.
4. I had a leaking o ring on the last blt, ive since replaced them.
5. I'll get to that haha, only going to be a cell phone pic though.
6. Thats next i guess. It was done once when i first looked at the car back in the spring.

 

[-red97rum-]

6. Thats next i guess. It was done once when i first looked at the car back in the spring.

I swear it should still stall up on a 14b unless your motor has absolutely NO compression. My engine, the way it currently is, has 65psi in cylinder #2 and 90 psi in cylinder #1. I'm currently building another engine for the car so I don't really care. But it still will stall up the HX35 in less than 10 seconds without the nitrous. I've ran my personal bests with the engine like it is. Check it anyway though just so you can get an idea of what shape that engine is in.

 

[91stocker]

I swear it should still stall up on a 14b unless your motor has absolutely NO compression. My engine, the way it currently is, has 65psi in cylinder #2 and 90 psi in cylinder #1. I'm currently building another engine for the car so I don't really care. But it still will stall up the HX35 in less than 10 seconds without the nitrous. I've ran my personal bests with the engine like it is. Check it anyway though just so you can get an idea of what shape that engine is in.

Wow, now im thinking there something really wrong .

Is there a trans or converter issue that could cause this? Like maybe a converter being super tight for some reason? Can the trans fluid effect it in anyway. The fluid visually checks out btw. Not saying its the wrong kind or something odd though.

The car runs and drives great. Pulls surprisingly well for a 14b. The motor feels strong, will do a compression test shortly still.

The thing that really has me stumped is that everything ive checked and changed hasnt changed anything. Always about 2700rpm and 3psi. Even with a terribly cracked auto manifold and a huge crack in the exhaust housing it did the same thing.

 

[HURRICANE HAVOK]

my car is doing the same. did u ever find out what happen.

 

[GDNF2ET]

1. Sorry if i worded it wrong, i have new tb gaskets on rebuilt stock tb.
2. Yes, stock cam gears.
3. I unhooked the downpipe and no change. Still only made 3psi after 10 seconds.
4. I had a leaking o ring on the last blt, ive since replaced them.
5. I'll get to that haha, only going to be a cell phone pic though.
6. Thats next i guess. It was done once when i first looked at the car back in the spring.

Did you ever figure out this problem ?