LS2 427 having issues...HELP
LS2 427 having issues...HELP Here is the setup I have. Built 427 resleeved LS2 block, . 4340 Forged Callies Steel Crank, Billet Steel Compstar Connecting Rods, Forged Aluminum Wiseco Ceramic Coated Pistons. MTI Stage III Ported & Polished Racing LS1 Cylinder Heads includes- Ferrea Stainless Steel 2.080” intake & 1.60” exhaust valves, custom double valve springs, titanium retainers, custom spring locators. MTI S1 cam 244/244dur .612/.612lift 112lsa. Fast 90/90. The car runs great other than it has a hard time finding it’s idle and seems to surge a lot. It also has oil consumption problems either thru the PCV system or bad valve guides and or valve seals. What I need help with is where to start. Do I try a catch can set up and see if that’s the oil consumption problem or go ahead and pull the heads and have all the seals checked? And what about the idle issues? Is it just the cam or is it a tuning thing or both(the car has been tuned and at first the idle issue went away but returned short after). I have read in other threads and forums that the fast TB is hard to work with, some have switched to the LS2 TB and have had good outcomes with idle issues with that switch. This car is not a track car strictly street HELP… best place to start?
I'd check the Map sensor to see if you have a leak. They don't fit very well on the FAST 90 intake and really need to have a good amount of RTV put on them sometimes to get a seal. ...mine did and this solved my idle problems.
Back of the intake, You will prolly have to pull the intake if you've never messed with it before. After you get used to it you can usually swap them without removal. I'll prolly catch **** but I would ditch the PCV system and run a breather can setup. I don't like any oil in my intake. Catch cans help but still let a little by. No matter what, they all do, even the good ones. That will let you know if it was the PCV system or something mechanical.
PS. I have a fast as well, it was on a turbo car before and the MAP was plugged with JB weld. I tapped into the brake booster with a T fitting. Like what the guys do with thier 2.5bar sensors. Zero chance of leakage that way.
PS. I have a fast as well, it was on a turbo car before and the MAP was plugged with JB weld. I tapped into the brake booster with a T fitting. Like what the guys do with thier 2.5bar sensors. Zero chance of leakage that way.
Back of the intake, You will prolly have to pull the intake if you've never messed with it before. After you get used to it you can usually swap them without removal. I'll prolly catch **** but I would ditch the PCV system and run a breather can setup. I don't like any oil in my intake. Catch cans help but still let a little by. No matter what, they all do, even the good ones. That will let you know if it was the PCV system or something mechanical.
PS. I have a fast as well, it was on a turbo car before and the MAP was plugged with JB weld. I tapped into the brake booster with a T fitting. Like what the guys do with thier 2.5bar sensors. Zero chance of leakage that way.
PS. I have a fast as well, it was on a turbo car before and the MAP was plugged with JB weld. I tapped into the brake booster with a T fitting. Like what the guys do with thier 2.5bar sensors. Zero chance of leakage that way.
There's a better and more permanent solution to secure the the MAP sensor to the FAST intake. See the attached pic below.
Your idle problem sounds like a tuning issue, but without datalogs it's just a guess. Oil consumption could be several things. Did you contact the engine builder? How many miles on the motor? How much oil consumption are you actually seeing? Any smoke from the exhaust? Those are old heads (good, but old). Were the reworked or gone through before you installed them?
Your idle problem sounds like a tuning issue, but without datalogs it's just a guess. Oil consumption could be several things. Did you contact the engine builder? How many miles on the motor? How much oil consumption are you actually seeing? Any smoke from the exhaust? Those are old heads (good, but old). Were the reworked or gone through before you installed them?
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It can effect idle yes. It sounds kind of tune related though. Removing the PCV is easy. Depending on your valve covers it can differ. Just involves plug and caping a few things and then putting either a breather on the oil fill cap or a nice breather can setup. The PS part was just another way of securing the MAP to the fast intake. What state do you live in? Do they have visual inspections?
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Verdad Gallardo There's a better and more permanent solution to secure the the MAP sensor to the FAST intake. See the attached pic below.
Your idle problem sounds like a tuning issue, but without datalogs it's just a guess. Oil consumption could be several things. Did you contact the engine builder? How many miles on the motor? How much oil consumption are you actually seeing? Any smoke from the exhaust? Those are old heads (good, but old). Were the reworked or gone through before you installed them?
Your idle problem sounds like a tuning issue, but without datalogs it's just a guess. Oil consumption could be several things. Did you contact the engine builder? How many miles on the motor? How much oil consumption are you actually seeing? Any smoke from the exhaust? Those are old heads (good, but old). Were the reworked or gone through before you installed them?
It can effect idle yes. It sounds kind of tune related though. Removing the PCV is easy. Depending on your valve covers it can differ. Just involves plug and caping a few things and then putting either a breather on the oil fill cap or a nice breather can setup. The PS part was just another way of securing the MAP to the fast intake. What state do you live in? Do they have visual inspections?
thanks for the pic and thats a perfect way to secure the map sensor. As far as the builder MTI out of houston no longer in business. motor has around 2200 miles on it white smoke on start up and smokes on hard excel and decel. Motor was complete assembled when I got it just swapped it in.
That's very low miles considering MTI has been out of business for quite a while. Did you buy it used? A catch can may help minimize the oil consumption but it sounds like it may have deeper issues. I would do both a compression and leak down test to start with and call a reputable engine builder for input. I would call Erik Koenig at HKE (sponsor here goes by user Racer7088) for his input.
no bought it from mti new. Car didnt see much driving time as I was still finishing school and moved due to career. Had a compresion test done all numbers came back good. Never done a leak down test though. Just now finding time to dig into the issues im having
Along with the car sitting alot for long periods of time it also had alot of dry starts which im sure didnt help with the seals. I dont know... I by no means am a motor know it all.
what am I looking for whats good whats bad. ?? I know what a leak down test is and how to go about doing it just not sure where thats gonna get me or what Im looking for
Last edited by SpinsB; Apr 18, 2011 at 09:24 PM. Reason: more thoughts
Starting to sound like a busted ring land....
Compression test, tells you which cylinder is worse than the rest.
Leak down test tells you how bad it is. It tells you how much leakage that cylinder has.
Both need the appropriate tool to perform the test. You can rent a compression tester at some parts stores.
When doing the leak down test, if you hear the air in the exh or intake it's a valve.
If it's in the valve cover it's a ring. Need a source of 100psi air to do it.
Oil smoke only on start up means it's a valve seal.
Oil on accel can be bad, it could be a bad intake gasket, wrong/stuck pcv valve, or bad/stuck rings, bad valve guides.
Decel only smoke can be any of the above.
Compression test, tells you which cylinder is worse than the rest.
Leak down test tells you how bad it is. It tells you how much leakage that cylinder has.
Both need the appropriate tool to perform the test. You can rent a compression tester at some parts stores.
When doing the leak down test, if you hear the air in the exh or intake it's a valve.
If it's in the valve cover it's a ring. Need a source of 100psi air to do it.
Oil smoke only on start up means it's a valve seal.
Oil on accel can be bad, it could be a bad intake gasket, wrong/stuck pcv valve, or bad/stuck rings, bad valve guides.
Decel only smoke can be any of the above.
Starting to sound like a busted ring land....
Compression test, tells you which cylinder is worse than the rest.
Leak down test tells you how bad it is. It tells you how much leakage that cylinder has.
Both need the appropriate tool to perform the test. You can rent a compression tester at some parts stores.
When doing the leak down test, if you hear the air in the exh or intake it's a valve.
If it's in the valve cover it's a ring. Need a source of 100psi air to do it.
Oil smoke only on start up means it's a valve seal.
Oil on accel can be bad, it could be a bad intake gasket, wrong/stuck pcv valve, or bad/stuck rings, bad valve guides.
Decel only smoke can be any of the above.
Compression test, tells you which cylinder is worse than the rest.
Leak down test tells you how bad it is. It tells you how much leakage that cylinder has.
Both need the appropriate tool to perform the test. You can rent a compression tester at some parts stores.
When doing the leak down test, if you hear the air in the exh or intake it's a valve.
If it's in the valve cover it's a ring. Need a source of 100psi air to do it.
Oil smoke only on start up means it's a valve seal.
Oil on accel can be bad, it could be a bad intake gasket, wrong/stuck pcv valve, or bad/stuck rings, bad valve guides.
Decel only smoke can be any of the above.
Shitcan the PCV, breather in the valve cover where the fill cap is, and just cap it all off. Save yourself alot of headaches in the long run that way.
Just clean that filter at every oil change.
Just clean that filter at every oil change.