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T3/T4 not spooling in first

Still sucks feeling the car begin pulling hard and then just be cut off. Still seems wrong although I guess that's what you get for running a big turbo. Hopefully an ipd turbo cam and my adjustable cam gear will help spool at least a bit, might start a thread about that. Maybe a chip to raise the rev limiter to 6700 would help.
 
That is a bit on the large side. I'm only running a 56-trim which on the setup I've got with a .63 hotside is still good for 400-450hp per Garrett.
 
So do you agree that it could just be lag? What part of the turbo would he best to change for faster spool? Smaller comp wheel? .48 AR housing? What's the cheapest way to quicken spool? I'm only aiming for around 300 BHP.
 
maxitoman007 said:
Update: did some research and I'm starting to think that it might just be because of how large my turbo actually is. With a 60 AR cold side .60 trim comp wheel, and a .63 ar exhaust side with a stage 3 turbine this much lag should be expected?
Click to expand...

Nope, something else is wrong, I haven't read the entire thread but for sure something else is wrong.

Can you get the WG to stick closed ( no vac lines to it) and see how the turbo spools?

Have you checked your timing and all of the basics? What cam?

with a chip you could rev it out to say 7000rpm, much better than the stock 6250.

If the car is not idling at 14.2-15.2 (aka 14.7:1) then you have something wrong, if the car is idling at 2000rpm then something is wrong. Is there any other TBer's near by that can stop by and help out? this sounds like a lot of basic stuff that an extra set of hands could help make sense of.

Have you done a pressure test and check for leaks?
 
I've heard 7000 is close to reaching valve float on these engines. Ugh, something is wrong!? I'll try with no lines going to the gate tomorrow possibly. I do have a plug I could use to temporarily close off the port on the mani. Just wishing I could spend a day with one of you Volvo gods and figure this out. I checked timing today and everything checks out. Still running the stock T cam but I'm hoping for an IPD turbo cam for Christmas haha.

Car is idling around 14.5 AFR at 1000 rpm. If I lean it out any more than that the idle gets rough. Like misfire rough. Even idling now it seems to miss occasionally. I did check for spark with a timing light and all cylinders are getting a consistent spark signal so that leaves fuel. I tried pulling the injector connectors but it seems to run strong on 3 cylinders with any 1 connector unplugged. Could possibly try running it on pairs to try and pinpoint a culprit cylinder. As for pressure testing I have not done that yet besides using my mouth haha I heard that if it was a boost leak through the intake it would be quite obvious so I figured human lung psi would suffice to find any large gaping leaks.

Don't know of any fellow TBers here in Calgary Alberta. Wishing the members map was working so I could find out haha.
 
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Did you do anything about the boost pressure over pressure switch. This switch is designed to cut the ground connection between the LH2.2 ECM and the fuel system relay upon the boost pressure exceeding the set limit resulting in shutting down the fuel pumps and the injectors.
 
The human psi will not be enough to find anything, build a pressure test setup, you do not need an air compressor as you can even just use a spare tire with 40-50psi to test it for a short time.

First test I would do is a pressure test, and then try with the WG closed or bypassed and be careful on the test drive as if all is well it should spool fairly quick and be unlimited boost so watch out. Only takes one or two times getting on the throttle to know that it is spooling correct. Once you know that you can figure out if you have the WG and EBC setup right.
 
How would I use the spare tire ?

GTJordan said:
I'm in Edmonton. But you'd have to get here....
Click to expand...

Thanks for the offer but I don’t think I’ll have the chance to make it out
there. Did find a couple people from calgary on here eventually and sent a couple pms, no replies yet though. My local Volvo club’s forum doesn’t seem to be very active anymore and I’m not even able to completely register so that doesn’t help.

lummert said:
Did you do anything about the boost pressure over pressure switch. This switch is designed to cut the ground connection between the LH2.2 ECM and the fuel system relay upon the boost pressure exceeding the set limit resulting in shutting down the fuel pumps and the injectors.
Click to expand...

There is no longer a boost line connected to the overboost switch so I don’t think that’s a possibility.
 
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I think I may have discovered something. I forgot to mention that I am pretty new to driving stick and boosted cars so I don’t really know what certain things feel like. I was driving with a buddy today and let him drive and he told me something wasn’t right. Rpms climbed waaay too quick after 4800 for how it felt. Initially he thought it was the clutch but even after doing multiple pulls, there was no smell. His other suggestion was tire spin. I’ve never thought about this but maybe I’m just losing traction when boost really comes on and that’s why the rpms shoot up late meaning it’s not a powerband issue.
 
Update: used a shrader valve and a pvc end cap to create a diy boost leak tester. Used a bike pump and found a signifivant leak in the tps side of the throttle body. Are there any bolts I could tighten here? Gaskets I could replace? O rings/seals I could replace?
 
There's an oring sealing the TPS to the throttle body, don't recall if that side also has a shaft seal. The other side has a seal. Pro tip, the part number for those seals is the same as the part number for valve hushers, per VIDA. The aftermarket hushers need just a tiny trim, otherwise they are too thick.
 
Ok managed to seal the throttle body tps side using a generic o ring. Now I found a new leak. Bubbles are now coming from the black idle adjustment thumb screw on the throttle body. How can I seal that? Teflon tape or something?

Edit: have done a little research and some people mention loosening a lock nut before being able to adjust they’re base idle. Don’t know if this applies to my throttle body but if it does I don’t believe I have a lock nut, just the thumb screw threaded in.
 
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maxitoman007 said:
Ok managed to seal the throttle body tps side using a generic o ring. Now I found a new leak. Bubbles are now coming from the black idle adjustment thumb screw on the throttle body. How can I seal that? Teflon tape or something?

Edit: have done a little research and some people mention loosening a lock nut before being able to adjust they’re base idle. Don’t know if this applies to my throttle body but if it does I don’t believe I have a lock nut, just the thumb screw threaded in.
Click to expand...

The thumb screw doesn't have a lock nut. The lock nut you're seeking is on the throttle lever adjustment screw. Time for more research.

http://www.turbobricks.com/forums/showthread.php?t=321181
 
Seems to me like he’s talking about the thumb screw adjustment here :

eurotrash940 said:
3. Adjusting the Idle Speed
On the front side of your throttle body, there is an adjustment screw.
Loosen the lock nut. Start the engine and turn the adjustment screw
until idle is 480-520 rpm. Switch off the engine and tighten the lock
nut while holding the adjustment screw so it doesn't turn.
Click to expand...

Can the throttle lever adjustment screw adjust idle speed? Because earlier in the article he already discusses how to set that screw, then he refers to the screw above as if it’s something the reader has not read about yet. I most certainly could be wrong but that’s just how I saw it.

Aside from that, does anybody know how I could seal those threads up? I was thinking (even if there isn’t a lock nut stock) I could thread a nut and an o ring under neath the nut on to the thumb screw before screwing it back in. Once the screw is set correctly, tighten down the nut with the o ring underneath hopefully sealing the threads.
 
Definitely time to read up on how it works. There's a throttle stop screw that yes, it can adjust the idle speed. Then on LH2.2 cars there's a thumbscrew as well to fine tune the adjustment, 2.4 cars don't have this.
 
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