Laggy 14b turbo?

[wildroot69]

I have a 92 eclipse GST, and it is really laggy. it does not achieve full boost till 3200-3500rpms. it has a few bolt on parts, hard intercooler pipes,3in downpipe/exhaust,ported 14b turbo 15psi etc.. it also is really slow to spool between wide open gear shifts. can i cure this with an 02 dump? it has stock 02 housing. Any help would be really apprieciated, Thanks!:

 

[mindset]

O2 dump will do nothing but help boost creep. Do a boost leak test.

 

[97-gst]

ive got an atmospheric 02 dump on mine and it doesnt really help. But if your looking to make your car real loud then you should get it.

 

[slow4g6392tsi]

If it's spooling slower than it should be it is most commonly one of two things:
1. Pre-turbo exhaust leak. (cracked manifold or exhaust housing, leaking between head and manifold, or leaking between manifold and turbo)
2. Worn out turbo.

It could be other things like boost leaks but those are the most common from what I have seen.

 

[turbolover10]

I agree check for pre turbo leaks and boost leaks. Its free and 9 times out of 10 you will find your problem..

Btw Boost creep will not be eliminated by an o2 dump! Only proper porting and/or an EXTERNAL wastegate will solve creep...

 

[JusMX141]

Common on older, high-mileage 14B's....results in added lag.

 

[ramsack]

if it's all of a sudden that this is happening then check for pre-turbo exhaust leaks or boost leaks. you mention the turbo is ported, is your manifold too? also you have "hard intercooler pipes." if they are a large diameter that will also increase lag as they will need time to fill up.

 

[99gst_racer]

It could be any of the following:

1) Pre-turbine exhaust leak. Check the gaskets on eich side of the manifold, and inspect the manifold and turbine housing for cracks.

2) Damaged turbine wheel. Inspect the turbine wheel to make sure it's intact and in good shape. If the blades are damaged or broken, it will cause a slow spool.

3) Boost leak. Do a boost leak test to rule this out.

4) Wastegate issue. Verify that the actuator is propperly functioning. Make sure it isn't allowing the flapper to blow open under load, and also verify that it's seated tightly over the port when in the closed position.


Chances are that one or more of these problems are causing your slow spool. Check all of these out and report back.

 

[wildroot69]

It has an evo3 exhaust manifold, im just waiting on my evo316g to arrive. it also has 2.5in intercooler pipes. didnt know that would cause lag.

is that carbon build up? that looks nasty. im getting ready to put a tubular o2 on it, can i use carb cleaner to clean the turbine housing?

 

[EclipticalGS]

what gear are you measuring these spool times in?

 

[wildroot69]

1st through 3rd gear. i think it might have a boost leak through the throttlebody seals. Does any have a cheap used throttlebody for sale? i just to lazy to take it apart and put seals in it.

 

[And_44]

So? From your OP I'm assuming that when you shift gears that it's not getting back up to boost? You venting your BoV or recirculating? Recirculating puts that boost back into the intake and starts spooling your turbo for the next gear. If it's recirculating I'd guess your BoV has a leak.

 

[92tsiawdguy]

Recirculating the bov doesn't help spool the turbo. The exhaust it what spools the turbo. Recirculation of the bov insures that the metered air re-enters the system keeping the a\f from going rich.

 

[And_44]

Recirculation gives the intake a precharge. Putting that air back into the intake on a near stock system will make the turbo work less in filling the lost volume of air. And yes it is metered air I understand that. Not doing so makes the turbo "lag" in cramming that air into the system. Larger turbo's can get away with venting because they can replace that lost air quicker. But a boost leak test will hunt down any problem.

A leak between your head and turbo though like what a poster posted above would cause turbo lag. I replaced a cruddy tubular exhaust manifold the previous owner had installed on my beast. The weld of the #1 runner at the collector had nearly come all undone. The turbo lag was horrible as most of the exhaust gasses that were suppose to turn turbo were escaping. Slapped on a 2g manifold and spool up was SwEeT.

 

[JusMX141]

Recirculating the bov doesn't help spool the turbo. The exhaust it what spools the turbo. Recirculation of the bov insures that the metered air re-enters the system keeping the a\f from going rich.

...BUT if you're not recirculating your car is going rich between shifts; meaning there will be less response / added lag due to a vented blow off valve.

I know, it's a technicality.

 

[pj91gsx]

It could be any of the following:

1) Pre-turbine exhaust leak. Check the gaskets on eich side of the manifold, and inspect the manifold and turbine housing for cracks.

2) Damaged turbine wheel. Inspect the turbine wheel to make sure it's intact and in good shape. If the blades are damaged or broken, it will cause a slow spool.

3) Boost leak. Do a boost leak test to rule this out.

4) Wastegate issue. Verify that the actuator is propperly functioning. Make sure it isn't allowing the flapper to blow open under load, and also verify that it's seated tightly over the port when in the closed position.


Chances are that one or more of these problems are causing your slow spool. Check all of these out and report back.

follow all this info, assuming that your ignition timing is properly set and spark plugs properly gapped. Major problem with these cars are BOOST LEAKS. most common place to leak is at the intercooler where the intercooler hoses clamp on the the intercooler, the intercooler holds dirt and corrodes. Also the throttle body shaft seals dry rot and leak too. It happens when cars get old.

 

[92tsiawdguy]

Damn you Justin! Lol