bad exhaust leak no boost???? sr20 - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

benarovi561 · 09-23-2011, 08:23 AM

ok so im trading my car to this guy. not going into detail. but its a sr20det with a aftermarket manifold and a 30trim turbo(thats what the guy said, idk). midmount setup. now heres the problem. the car had a real bad exhaust leak from the manifold somwhere. it doesnt boost at all. thats why im making this thread. now the turbo to manifold 4 bolt flange does not have the locking tabs. and all 4 bolts were on the manifold. i floorded it till bout 5k no boost at all. my question is the leak that bad where the turbo cant spool?? i had no locking plates and 3 bolts and blown gasket on my stock t25 and it still went into boost. im trying to find out what it is.could it be bad wastegate, siezed turbo, or just the 4 bolts are so loose it cant boost?? the mani is heat wraped, and u can see wher the 4 bolt flange is, the heat wrap is burnt alittle. the car has 750cc injectors on a fuel rail and fpr. i really want to trade the guy but the no boost is scaring me. i dont want the motor to loose compression cuz the rings got burnt to shit from running so lean. please post and let me know

benarovi561 · 09-23-2011, 08:24 AM

woops ment to put this in tech

Sileighty_85 · 09-23-2011, 08:28 AM

You should read up how a turbo charged engine works.

when you do you will understand why your not building boost

blueshark123 · 09-23-2011, 08:37 AM

You should do a leak down test on the motor and a compression test atleast. I was able to create boost on a customers car that had all the bolts loose even 1 bolt was missing but it didnt create full boost and it was defitnetly slower. this is where it attaches to the down pipe and it was t28 stock turbo setup.

HPKMotorsports3 · 09-23-2011, 08:52 AM

check to see if the wastegate came off the turbo meaning the bolts that hold it up fell out... happened to me... if not do a leak down test like blue shark said

benarovi561 · 09-23-2011, 09:24 AM

Quote:

Originally Posted by Sileighty_85

You should read up how a turbo charged engine works.

when you do you will understand why your not building boost

i realize that exhaust leak but i had a bad exhaust leak and blown gasket and my t25 still spooled. its just funny how it doesnt spool at all

Sileighty_85 · 09-23-2011, 10:26 AM

Quote:

Originally Posted by benarovi561

i realize that exhaust leak but i had a bad exhaust leak and blown gasket and my t25 still spooled. its just funny how it doesnt spool at all

T25 are tiny so if the gasket leaks it will still build some boost. A 30 Trim is a bit bigger requiring more exhaust gases to spool and compress the air so if theres a fairly big leak it wont boost

leung · 09-23-2011, 10:32 AM

check if the manifold has cracks in it.

Boost_Fiend · 09-23-2011, 10:55 AM

Every time iv'e had an exhaust leak I was able to hear where it was coming from. After my rebuild I forgot to tighten the bolts on the manifold and I was still able to produce boost on my gt28. It was slow and sounded terrible but it was building boost. Look and feel around the exhaust side and search for leaks.

sr20det_03 · 09-23-2011, 11:11 AM

for it to not boost at all it would have to be quite a large crack in the manifold (huge) and even if the 4 bolts werent completely tight it would still put out a little unless the bolts aren't there at all unless it's externally wastegated and it is just hanging there or a charge pipe just blew off and you haven't looked. Make sure everything is attached properly.

benarovi561 · 09-23-2011, 11:21 AM

yea its not external. and dought thers a crack that big because its fairly neew manifold and heat wrapped. i just dont want to get the car and a week later the rings burn up

blueshark123 · 09-23-2011, 11:50 AM

Sounds like your buying someones headache here

09-23-2011, 08:23 AM	#1
benarovi561 In time-out for misbehaving. Join Date: Jun 2011 Location: texas Age: 37 Posts: 80 Trader Rating: (0) Feedback Score: 0 reviews	bad exhaust leak no boost???? sr20 ok so im trading my car to this guy. not going into detail. but its a sr20det with a aftermarket manifold and a 30trim turbo(thats what the guy said, idk). midmount setup. now heres the problem. the car had a real bad exhaust leak from the manifold somwhere. it doesnt boost at all. thats why im making this thread. now the turbo to manifold 4 bolt flange does not have the locking tabs. and all 4 bolts were on the manifold. i floorded it till bout 5k no boost at all. my question is the leak that bad where the turbo cant spool?? i had no locking plates and 3 bolts and blown gasket on my stock t25 and it still went into boost. im trying to find out what it is.could it be bad wastegate, siezed turbo, or just the 4 bolts are so loose it cant boost?? the mani is heat wraped, and u can see wher the 4 bolt flange is, the heat wrap is burnt alittle. the car has 750cc injectors on a fuel rail and fpr. i really want to trade the guy but the no boost is scaring me. i dont want the motor to loose compression cuz the rings got burnt to shit from running so lean. please post and let me know

09-23-2011, 08:28 AM	#3
Sileighty_85 Post Whore! Join Date: Dec 2006 Location: Misawa, Japan Posts: 6,815 Trader Rating: (8) Feedback Score: 8 reviews	You should read up how a turbo charged engine works. when you do you will understand why your not building boost __________________ 後輪駆動車１番 1989 Built SR GT2871R -363whp 1998 S14 W/RB25- 250ish (For Now) 1986 SR86 - 200ish 1990 R32 GTR - 320hp Don't Buy Engines from JDM-Online http://zilvia.net/f/businesses/207457-jdm-online.html Don't Buy XS-Power or SSAC Shit

09-23-2011, 08:24 AM	#2
benarovi561 In time-out for misbehaving. Join Date: Jun 2011 Location: texas Age: 37 Posts: 80 Trader Rating: (0) Feedback Score: 0 reviews	woops ment to put this in tech

09-23-2011, 08:37 AM	#4
blueshark123 Post Whore! Join Date: Apr 2006 Location: North Jersey Posts: 5,481 Trader Rating: (55) Feedback Score: 55 reviews	You should do a leak down test on the motor and a compression test atleast. I was able to create boost on a customers car that had all the bolts loose even 1 bolt was missing but it didnt create full boost and it was defitnetly slower. this is where it attaches to the down pipe and it was t28 stock turbo setup.

09-23-2011, 10:32 AM	#8
leung Zilvia FREAK! Join Date: May 2010 Location: NYC - HK Posts: 1,234 Trader Rating: (73) Feedback Score: 73 reviews	check if the manifold has cracks in it.

09-23-2011, 10:55 AM	#9
Boost_Fiend Zilvia Member Join Date: Jan 2009 Location: Ft. Lauderdale, FL Posts: 199 Trader Rating: (0) Feedback Score: 0 reviews	Every time iv'e had an exhaust leak I was able to hear where it was coming from. After my rebuild I forgot to tighten the bolts on the manifold and I was still able to produce boost on my gt28. It was slow and sounded terrible but it was building boost. Look and feel around the exhaust side and search for leaks.

09-23-2011, 11:11 AM	#10
sr20det_03 Join Date: Sep 2011 Location: Central New York Age: 36 Posts: 15 Trader Rating: (0) Feedback Score: 0 reviews	for it to not boost at all it would have to be quite a large crack in the manifold (huge) and even if the 4 bolts werent completely tight it would still put out a little unless the bolts aren't there at all unless it's externally wastegated and it is just hanging there or a charge pipe just blew off and you haven't looked. Make sure everything is attached properly.

09-23-2011, 11:21 AM	#11
benarovi561 In time-out for misbehaving. Join Date: Jun 2011 Location: texas Age: 37 Posts: 80 Trader Rating: (0) Feedback Score: 0 reviews	yea its not external. and dought thers a crack that big because its fairly neew manifold and heat wrapped. i just dont want to get the car and a week later the rings burn up

09-23-2011, 11:50 AM	#12
blueshark123 Post Whore! Join Date: Apr 2006 Location: North Jersey Posts: 5,481 Trader Rating: (55) Feedback Score: 55 reviews	Sounds like your buying someones headache here