horrible lag!!

[slowgsr]

Hi, my setup is in my profile.

Anyways, my car has such horrible lag.. In 1st gear i can only make 1.15bar and in 2nd i only make 1.22ish bar, this is pulling to 7200.

In 3rd and 4th i hit full boost of 1.5bar around 5000rpm, which seems very late for the size of turbo im using.


So im thinking i have a boost leak? The spool time was around the same on the dyno as well in 3rd & 4th.

Everything is tbolts and 4plys silicone couplers all new, the charge piping system is new and fits very well, but i must have a leak.

So what do you all think? Is a boost leak probably the issue here? Im using a tial 50mm bov as well.

When i do a boost leak test, do i need to remove the charge piping from the TB, and cap it there, then pull it off the turbo and apply pressure and check? Or can i leave it connected to the intake manifold.. I thought it would leak out through the motor though.. (could be wrong)

Thanks! Hopefully its just a boost leak somewhere, the powerband of 2000ish rpm is horrible (only reving to 7k)

Just another Question, how high can i rev my stock 6 bolt? I have FP stage 2 cams and revised topline lifters, valves/retainers stock.

Thanks.. If i could go to 76-7700 that would help out with my powerband atleast.

 

[talon96tsi]

When are you hitting full boost? A turbo that size isnt going to spool like the factory turbo, its much bigger. I would think you would hit full boost before 4500rpm. Is the car tuned? what is your boost pressure set at? I have always put my tester on the turbo inlet and tested the charge piping. You can test it again at the tb elbow to make sure everything is ok on the manifold side. This doesnt seem like a boost leak to me, you should be experiencing drivabilty problems as well. Either way, for peace of mind i would definatly do the boost leak test.

 

[anteversion]

sounds like a wastegate trouble, the thing is staying open or partially open at all time so boost can not be builded in that case. look for this and the adjustment of the wastegate spring.

for a boost leak test put your engine at tdc with the throttle at wot and then apply pressure in your piping from the outlet of the turbo piping

 

[slowgsr]

the car is tuned, im hitting full boost by 5100 in 3rd and 4th, will not hit full in 1st and 2nd (running 1.5bar full).

No problem with wastegate or boost controller setup. May be boost leak, but i will either need to rev this higher, or spray nitrous to help with the lag issue if there is really 'no' problems with it.

Thanks.

 

[anteversion]

so waht is your boost is setting to??? a big turbo with like 8-10 psi of setting boost will not get enough exhaust flow for boosting in first and second gear

1.5 bar is around 22 psi right

 

[slowgsr]

1.5 bar is around 22 psi right

yeah sorry, my boost controller, gauge etc.. is all in kg/cm3 which is very close to 1:1 with bar.

Im running 1.5 kg/cm3 which is about 22psi.

 

[anteversion]

what about your blow off hoses, how did you routed it??

 

[90laserRSfwd]

When did you expect a 60-1 to spool on a 2 litre engine? a 35r spools around 4800 and it's ball bearing...

 

[anteversion]

imnot very experienced with theses big turbos, maybe is it just normal to act like this... for sure its compromise to have bigger turbine, more you took big size, more lag you have

 

[slowgsr]

P-Trim 60-1, T04b turbo.. Im just not very happy with the powerband i guess, thats all.

I rip it though the gears at the track, and between shifts it drops out of boost by about 1200rpm, so the car is a dog at the track.

For 3rd and 4th gear pulls on the freeway it flys though.

 

[anteversion]

yeah get something smaller with good cfm counts. you will be even more faster than with this one.

 

[No_Skillz]

Just because you have new pipes and 4 ply couplers doesn't mean you don't have leaks. It sounds like you've never done a BLT before. You'll be surpised at the number of leaks you will find.

 

[spaugh]

When are you hitting full boost? A turbo that size isn't going to spool like the factory turbo, its much bigger. I would think you would hit full boost before 4500rpm. Is the car tuned? what is your boost pressure set at? I have always put my tester on the turbo inlet and tested the charge piping. You can test it again at the tb elbow to make sure everything is ok on the manifold side. This doesn't seem like a boost leak to me, you should be experiencing drivabilty problems as well. Either way, for peace of mind i would defiantly do the boost leak test.

With the EMS the air does not get metered until it reaches the map sensor. Witch is normally ran off the intake manifold. So a boost leak wouldn't really effect the running of his car like a car with a normal 1g or 2g mas.

With everything you have said the only things that could really be is a boost leak, something internally wrong with the turbo, or a restriction of air getting into or out of the turbo.

Also, were is you boost gauge metering from?

 

[slowgsr]

I have never done a boost leak test before, and your right, i do hope i find a bunch of leaks . Going to do one this week.

Im running a 3" intake on the turbo just to infront of the transmission, with a shitty filter on there (im going to pull the filter for a pull and just run a screen and see if it helps.. never know).

As for a problem with any of the other components, i doubt it, everything is new, installed properly etc, and this isn't my first turbo setup either i also own a turbo honda. The manifold is a SLS, and its 3" turboback, my exhaust only has 2 90's and a 45 and thats including the downpipe.

As for boost pressure measurement, my EMS measures it from my map which is mounted in the bottom of the intake manifold in a aluminum bung, my boost controller has a sensor mounted in the manifold and the controller itself gets its vac from the compressor housing (wastegate source), and i have another greddy gauge that gets its source from another sensor on the intake.

The EMS loggs the same pressures that the boost controller logs, as well as my greddy gauge that i can view.

Thanks.

Will do a test and get results up.

 

[rhamlinii]

, what did you expect with a p trim exhaust wheel? I feel bad you only have a to4b compressor housing. Atleast, I had the to4s with a 4inch inlet. I'm not really sure what to tell you. That sounds about right for when I was runing my turbo on stock 1g pistons and with my race head. If you keep it at that boost level you should be fine to rev it out to 7700-8000 rpm. If you increase the boost past 20 psi, i'd rev it out to 7200-7500. Just don't miss a shit trying to keep it in boost. You could add a 50 shot to it, and it'll feel like a 50 trim. What A/R exhaust housing do you have? I think that to4b compressor housing won't let you take the turbo to it's sweet spot anyway. Some will tell you they have done it to 8500 on stock springs, but I wouldn't trust it. I've done it, but you shouldn't.

*If you have a non-factory ecu. Tune the part of the map where you don't spool like an all motor car 30 dergree's of timing and 13.0 air fuel levels. You may be able to pick up an 500-800 rpm in spool time on a 3rd gear pull. Alot more on a 4th gear pull, because of the load on the motor.* My friend was able to spool a t-67 with a p trim wheel. Boost started at 5200, and full boost 17 psi was at 6200 in 3rd gear and he carried it to 9500. This was also a 8.5 to 1 motor @ 81.5mm bore b16 motor w/ a stock crank. I was on a afc hack at the time with my car so I was limited to what I could do with my car. His car went 10's on pump gas and slicks. 10.90s @ 131 not that it's relative to you. Car made 450whp.

 

[slowgsr]

7600rpm would be nice.. Im going to turn it a bit higher, and check for boost leaks tommorow and see how it does.

I dont know the exact specs of the turbo.. I will see if i can get someone to chime in here.

Thanks.

 

[fwdeclipse]

Had that same setup last winter and hated it for that same reason.

 

[slowgsr]

Had that same setup last winter and hated it for that same reason.

I dont hate it, the car is great for freeway racing. Just having a hard time getting it down the 1320 quickly.

I did a boost leak test, found 4 leaks (bov, tb gasket, 2 couplers) and now i hit full boost about 250rpm sooner.

I will also turn the engine 650-700rpm higher (to 7700rpm)

So i will get another ~900rpm of powerband which will pretty much keep me in boost during shifting, especially with the antilag.

I also can hit full boost in 1st, and 2nd its a bit later then in 3rd +, but atleast i can build full boost in the early gears.

Good for now.

 

[diambo4life]

P-trim wheel is too big for that compressor IMO. You would have been happier with a smaller stage 3 turbine wheel. That's where I would expect the car to spool. There's nothing wrong. Need to put a real rev limiter on there. It's not a stock turbo where you rev to 7k.

 

[IPT]

Who is tuning your AEM??

 

[slowgsr]

the aem was tuned by dynamotorsports a local shop, they are certified AEM tuners.

I will rev it to 7600 and see how the boost feels between shifts.