14b should full boost at what rpm?

[joe sobo]

i have completly stock 92 tsi 5 speed. i am having a couple of problems.
i had horrible boost leak at injector seals, so i just replaced them. was holding at 14 psi of boost nicely.put the new seals in, now once i hit 10 psi the car starts sputtering. i know the just a a/f guage is not accurate, but when the sputtering starts, the guage sputters in red (lean) at the same time.

when we redid boost leak test, the only boost leak the i had was at the injectors, but i fixed them. what else???????
any advice would be greatly appreciated
also, at what rpm should a 14b reach full boost?

 

[DeNoZZo]

i have completly stock 92 tsi 5 speed. i am having a couple of problems.
i had horrible boost leak at injector seals, so i just replaced them. was holding at 14 psi of boost nicely.put the new seals in, now once i hit 10 psi the car starts sputtering. i know the just a a/f guage is not accurate, but when the sputtering starts, the guage sputters in red (lean) at the same time.

when we redid boost leak test, the only boost leak the i had was at the injectors, but i fixed them. what else???????
any advice would be greatly appreciated
also, at what rpm should a 14b reach full boost?

Mine reaches full boost at around 3500-4000 rpm

 

[Burtismaximus]

so your car is completely stock. and when you do a blt now it leaks at the injector seals.
well check to see if you are losing fuel at all. i had a problemy kinda like this when i put my 550s in. just check to see if there is any gas or anything on the intake manifold and try to be a little more clear i am having trouble trying to figure out what your saying. and yes my 14b gets full boost at 4000 rpms. and im running 19lbs

 

[Boost92awd]

You need to do another boost leak test and spray everything down with soapy water. Spray soapy water on your vacuum lines,BOV flange, UICP and LICP couplers, Injectors, Throttle body. This will help you find those little leaks.

 

[joe sobo]

i replaced the injector seals, so they are out of the question. but i did ablt again and find none

 

[joe sobo]

what else i don't understand is how everyone says how quick a 14b spools up, but if it at 4000 rpm then my last dsm with a 60-1 was only at 4400...........

 

[webconnect]

I have a small 16g which is a little bigger than a 14b. It gets full boost by 2,800 rpm. You guys need to get boost leak tests, and exhaust leak tests!

 

[whiteflash]

My 14b w/ a 3n TBE spooled 19-20psi by 2800

 

[big_d]

Yeah, I hit full boost with my beater car's 14b at about ~2700 (12-13psi). My good car's evoIII hits full boost about ~3200 (19psi).

 

[tkelly27]

You probably have a leak after the MAF but before the turbo.

 

[jrohner]

I couldn't imaging having a turbo that small spool as terrible as some of you guys -- are most of you talking about 1st gear or something -- you should only talk about spool in the higher gears. You should get full boost at 2500 to 3 grand at the highest. Even my E3 16G could do 20+psi by 2500 until I installed a FMIC -- now its 2700-2800rpms.

Main causes of slow spool - exhaust leak before the turbo (extremely slow spool), base timing set too high, boost leak, low compression, wastegate flapper not fully closed.

If you have a boost leak, your car should run much richer - not leaner. If your car is misfiring really bad, the o2 sensor reading may get thrown off (narrowband or even wideband). If it's lean, you probably have an issue with an injector. Do you have a logger? You can watch your fuel trims -- high means lean, which points to a possible injector issue. I've had injectors act up before and then all of a sudden be fine again -- one set did after a boost leak test, and another couple sets randomly a time or two.

 

[joe sobo]

I couldn't imaging having a turbo that small spool as terrible as some of you guys -- are most of you talking about 1st gear or something -- you should only talk about spool in the higher gears. You should get full boost at 2500 to 3 grand at the highest. Even my E3 16G could do 20+psi by 2500 until I installed a FMIC -- now its 2700-2800rpms.

Main causes of slow spool - exhaust leak before the turbo (extremely slow spool), base timing set too high, boost leak, low compression, wastegate flapper not fully closed.

If you have a boost leak, your car should run much richer - not leaner. If your car is misfiring really bad, the o2 sensor reading may get thrown off (narrowband or even wideband). If it's lean, you probably have an issue with an injector. Do you have a logger? You can watch your fuel trims -- high means lean, which points to a possible injector issue. I've had injectors act up before and then all of a sudden be fine again -- one set did after a boost leak test, and another couple sets randomly a time or two.

thank you for all the VALID info. i also assumed that my car hitting full boost at 3400-3800 is totally crazy. so i just got done taking my 1g mani. off figuring that they crak up so bad. the top has no cracks at all, but once taken off, i can stick a quarter in the cracks on the bottom side. Also you point out that wastegate flapper isn't shutting properly....BINGO. the exaust housing has so many and so huge of cracks around the flapper that even when it's shut, you can see through it all the way around it.
i'll update once im done fixing everthing

 

[Burtismaximus]

sorry about that i was talking about in first gear and even then its most likely sooner. i would really have to watch it and look at it through other gears. I know my turbo spools faster than most others because of my hogged out evo3 manifold and 02 housing. to the op are you venting at all and left that hole open on the intake pipe??/

when turbo spools it doesnt mean full boost. what i meant is the rpm it was at where it held a full 19lbs of boost. it has 10 to 15 really early i can check tomarrow to make sure but ill post back for ya

 

[jrohner]

when turbo spools it doesnt mean full boost. what i meant is the rpm it was at where it held a full 19lbs of boost. it has 10 to 15 really early i can check tomarrow to make sure but ill post back for ya

We are talking about full boost. You can't go by what it boosts at in the lower gears because the engine revs up too fast and not everyone's is going to rev up as fast; especially having an aluminum flywheel like mine does.

 

[JusMX141]

Mine reaches full boost at around 3500-4000 rpm

Something's wrong.

You should be seeing full boost around 2800....possibly sooner being that your car has 8.5:1 compression versus a 1G's 7.8:1.

Make sure your wastegate flapper is sealing properly.

 

[joe sobo]

Something's wrong.

You should be seeing full boost around 2800....possibly sooner being that your car has 8.5:1 compression versus a 1G's 7.8:1.

Make sure your wastegate flapper is sealing properly.

duh,,,,, i have a 1g

 

[costas14]

my 90gst hit full boost at 3k rpm, while my 95 gsx with the t25 hits it at the same

 

[JusMX141]

duh,,,,, i have a 1g

Interesting....I didn't see "Joe Sobo" in the quote box for post #15.

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[Turbo Talon DL]

He's trying to first figure out how to get the car to stop running lean under boost which is a perfectly good conclusion as to why he says the car is bogging. You could have a pre-turbo boost leak somewhere after the MAF or a leak after the turbo which could actually cause a rich condition rather than lean. But what would happen if you added fuel cut into the equation? Could that explain the lean flicker on the A/F gauge? A (signifigant) boost leak after the turbo can cause the stock boost gauge to read 3 psi, bog, and idle surge very badly along with a rich reading on the A/F gauge.

Do you have a datalogger? This would help you figure out why you're cutting out and if you do have boost leaks before or after the turbo.

 

[delta448]

14b on '97 AWD:
Stock downpipe = 17psi @ ~3100-3200 in 2nd gear
3" TBE = 17psi @ ~2700-2800 in 2nd gear

Did you tap the stock O2 sensor for your NB gauge? It may be degrading the signal enough to cause a lean condition on both the gauge and in the eyes of the ECU, which likely causes you to actually run extra rich. Especially true if the wiring was poorly done. Warm the car up, do a fairly aggressive pull, shut the car off immediately and pull a plug, is it black or tan?

 

[joe sobo]

well, to update, i pulled everything apart put 2g mani,(1g was cracked all up on the bottom side, my flapper was destroyed,( was not even over the hole), and horrible exaust leaks. fixed everything, now full boost at like 3100. by 3500 im now at like 17 p.s.i and hit fuel cut, so i need a pump and fpr

 

[JusMX141]

Ah yes, the ol' flapper sleeve walked out of the housing. Common problem on 14B's that ruins a hell of a lot of good turbine housings.

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[gorf]

well, to update, i pulled everything apart put 2g mani,(1g was cracked all up on the bottom side, my flapper was destroyed,( was not even over the hole), and horrible exaust leaks. fixed everything, now full boost at like 3100. by 3500 im now at like 17 p.s.i and hit fuel cut, so i need a pump and fpr

you might be able to get even a little lower if you pre-load your actuator. Just slip some washer under the actuator mount bolts to pull it a little tighter. You can do this from the front of the car without pulling anything but the mounting bolts for the actuator.

 

[joe sobo]

Ah yes, the ol' flapper sleeve walked out of the housing. Common problem on 14B's that ruins a hell of a lot of good turbine housings.

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exactly what mine did. i just put it in a vise andperssed it back in. hope it holds up