Big cubes guys get in here
Thread Starter
Drifting
Joined: Dec 2002
Posts: 1,472
Likes: 1
From: Reynoldsburg oh
Big cubes guys get in here
What problems have you had since you went with bigger cubes. Here are mine.
Motor has smoked since it was installed. White smoke not black. It did it on start up mostly. Did a leak down test and it read good. It was 190 all around. So that leads me to believe it is the valve seal. So goin to replace those.
Then crank bolt has backed itself out 2x already in 2 weeks. I have applied red lock tight to the threads both times. This is a arp bolt.
Next I pulled the intake to find a ton of oil dripping out of it. Also there was oil in the throttle body and air bridge. Now I am doin a catch can. Seems like since I went with a bgger cube motor, the money never stops getting tossed at it to try to get it run correctly..
I have talked to acouple of the other big cube motor vettes here, 2 427's and 1 402, all of them are also experiencing problems. One has all the same problems I am having.
Anyone else having issues with their motors...
Rant off///
Motor has smoked since it was installed. White smoke not black. It did it on start up mostly. Did a leak down test and it read good. It was 190 all around. So that leads me to believe it is the valve seal. So goin to replace those.
Then crank bolt has backed itself out 2x already in 2 weeks. I have applied red lock tight to the threads both times. This is a arp bolt.
Next I pulled the intake to find a ton of oil dripping out of it. Also there was oil in the throttle body and air bridge. Now I am doin a catch can. Seems like since I went with a bgger cube motor, the money never stops getting tossed at it to try to get it run correctly..
I have talked to acouple of the other big cube motor vettes here, 2 427's and 1 402, all of them are also experiencing problems. One has all the same problems I am having.
Anyone else having issues with their motors...
Rant off///
Melting Slicks
Joined: Jun 2004
Posts: 3,439
Likes: 6
From: Newark, DE
St. Jude Donor '06
I'm not sure if you are looking for someone to commiserate with or to tell you that big cubes are not a problem. FWIW, I've had my share of issues, but none of them have been attributable to my stroker motor.
When you say "smoking" do you mean off the block or out the tailpipe?
When you say "smoking" do you mean off the block or out the tailpipe?
Team Owner
Joined: May 2005
Posts: 23,682
Likes: 9
From: Flagstaff Az.
smoke
Since you found a lot of oil in the intake, I would hold off on the valve seals until I got the intake problem solved. I have not run a large ls1 but have had a lot of big cube small blocks in the last 50 years and have not had any trouble with them that didn't occur in the small cube motors.
Melting Slicks
Joined: Jul 2004
Posts: 2,507
Likes: 0
From: Wilmington Ca.
Originally Posted by RamonaC5
Mine's been running about a month now with 500 miles no problems...knock on wood.
Just kidding
Last edited by frank dupuy; Jul 26, 2006 at 01:30 AM.
Safety Car
Joined: Jan 2001
Posts: 3,879
Likes: 3
From: Hobart, WI
True white smoke is coolant but check your rocker bolts. With ported heads you need to put sealant on those bolts.
The ARP crank bolts require moly lube and 197 lbs of torque- no Locktite.
I would try updating the PCV system to 05 which means no vents in valve covers except front pass cover to TB and LS2 valley. This is the toughest issue.
The ARP crank bolts require moly lube and 197 lbs of torque- no Locktite.
I would try updating the PCV system to 05 which means no vents in valve covers except front pass cover to TB and LS2 valley. This is the toughest issue.
Thread Starter
Drifting
Joined: Dec 2002
Posts: 1,472
Likes: 1
From: Reynoldsburg oh
Originally Posted by see5
True white smoke is coolant but check your rocker bolts. With ported heads you need to put sealant on those bolts.
The ARP crank bolts require moly lube and 197 lbs of torque- no Locktite.
I would try updating the PCV system to 05 which means no vents in valve covers except front pass cover to TB and LS2 valley. This is the toughest issue.
The ARP crank bolts require moly lube and 197 lbs of torque- no Locktite.
I would try updating the PCV system to 05 which means no vents in valve covers except front pass cover to TB and LS2 valley. This is the toughest issue.
Anyways this was just a rant post, carry on with your day...
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Former Vendor
Joined: Dec 2004
Posts: 415
Likes: 0
From: Denver CO
I have a 402 motor in my car and no problems what so ever 
... I did have some "reduced engine power Issues" but this was old grounds as well as bad wiring from the small flash fire I had when my original motor went BOOM!
Good luck
... I did have some "reduced engine power Issues" but this was old grounds as well as bad wiring from the small flash fire I had when my original motor went BOOM! Good luck
Melting Slicks
Joined: Jul 2004
Posts: 2,507
Likes: 0
From: Wilmington Ca.
Originally Posted by RamonaC5
Frank You're killing me. Are you going to make it to our SCMR on Aug 5??
Last edited by frank dupuy; Jul 27, 2006 at 12:45 PM.
Drifting
Joined: Mar 2005
Posts: 1,737
Likes: 0
From: Northern VA
Originally Posted by sprayedc5
Motor has smoked since it was installed. White smoke not black. It did it on start up mostly. Did a leak down test and it read good. It was 190 all around. So that leads me to believe it is the valve seal. So goin to replace those.
Then crank bolt has backed itself out 2x already in 2 weeks. I have applied red lock tight to the threads both times. This is a arp bolt.
Next I pulled the intake to find a ton of oil dripping out of it. Also there was oil in the throttle body and air bridge. Now I am doin a catch can. Seems like since I went with a bgger cube motor, the money never stops getting tossed at it to try to get it run correctly..
Rant off///
Then crank bolt has backed itself out 2x already in 2 weeks. I have applied red lock tight to the threads both times. This is a arp bolt.
Next I pulled the intake to find a ton of oil dripping out of it. Also there was oil in the throttle body and air bridge. Now I am doin a catch can. Seems like since I went with a bgger cube motor, the money never stops getting tossed at it to try to get it run correctly..
Rant off///
You need to get a cylinder leak down test performed (ring seal).
Did you pin your crank?
Pro
Joined: Jun 2005
Posts: 734
Likes: 0
From: Austin TX
If you're seeing smoke on startup and you have oil in your intake why would you replace valve seal. If oil is going from you intake into your combustion chamber...that'll cause smoke. I'd put a catch can in there and run some seafoam to get as much as the carbon/oil out....if you stil l have the smoking issue then I'd look to valve seals.
As for the crank bolt...try a new one and follow the instillation instructions exactly.
I have a 383 LS1 and I experience the "smoking" issue along with oil consumption. I built a catch can last night. I'm installing it in 2 hours so I'll post tomorrow if this fixed my issue.
As for the crank bolt...try a new one and follow the instillation instructions exactly.
I have a 383 LS1 and I experience the "smoking" issue along with oil consumption. I built a catch can last night. I'm installing it in 2 hours so I'll post tomorrow if this fixed my issue.
Thread Starter
Drifting
Joined: Dec 2002
Posts: 1,472
Likes: 1
From: Reynoldsburg oh
Originally Posted by Boob
If you're seeing smoke on startup and you have oil in your intake why would you replace valve seal. If oil is going from you intake into your combustion chamber...that'll cause smoke. I'd put a catch can in there and run some seafoam to get as much as the carbon/oil out....if you stil l have the smoking issue then I'd look to valve seals.
As for the crank bolt...try a new one and follow the instillation instructions exactly.
I have a 383 LS1 and I experience the "smoking" issue along with oil consumption. I built a catch can last night. I'm installing it in 2 hours so I'll post tomorrow if this fixed my issue.
As for the crank bolt...try a new one and follow the instillation instructions exactly.
I have a 383 LS1 and I experience the "smoking" issue along with oil consumption. I built a catch can last night. I'm installing it in 2 hours so I'll post tomorrow if this fixed my issue.
Well the car has smoked on start up then it would be ok, so I was always told it was the stem seals. Since the car is apart anyways I am goin to go ahead and replace them now then do it later.
I did a leak down test on the shortblock and it was 190 all around.
Drifting
Joined: Mar 2005
Posts: 1,737
Likes: 0
From: Northern VA
Originally Posted by sprayedc5
Well the car has smoked on start up then it would be ok, so I was always told it was the stem seals. Since the car is apart anyways I am goin to go ahead and replace them now then do it later.
I did a leak down test on the shortblock and it was 190 all around.
I did a leak down test on the shortblock and it was 190 all around.
Did you pin the crank or not?
Thread Starter
Drifting
Joined: Dec 2002
Posts: 1,472
Likes: 1
From: Reynoldsburg oh
Originally Posted by FRCTony
You did a compression test, not a leak down test... you need to do this instead of guessing.
Did you pin the crank or not?
Did you pin the crank or not?
Have not pinned the crank yet. I am waiting for a few things then I will be pinning it as well.
Drifting
Joined: Dec 2002
Posts: 1,361
Likes: 0
From: Forest Hill MD
Originally Posted by sprayedc5
What problems have you had since you went with bigger cubes. Here are mine.
Motor has smoked since it was installed. White smoke not black. It did it on start up mostly. Did a leak down test and it read good. It was 190 all around. So that leads me to believe it is the valve seal. So goin to replace those.
Then crank bolt has backed itself out 2x already in 2 weeks. I have applied red lock tight to the threads both times. This is a arp bolt.
Next I pulled the intake to find a ton of oil dripping out of it. Also there was oil in the throttle body and air bridge. Now I am doin a catch can. Seems like since I went with a bgger cube motor, the money never stops getting tossed at it to try to get it run correctly..
I have talked to acouple of the other big cube motor vettes here, 2 427's and 1 402, all of them are also experiencing problems. One has all the same problems I am having.
Anyone else having issues with their motors...
Rant off///
Motor has smoked since it was installed. White smoke not black. It did it on start up mostly. Did a leak down test and it read good. It was 190 all around. So that leads me to believe it is the valve seal. So goin to replace those.
Then crank bolt has backed itself out 2x already in 2 weeks. I have applied red lock tight to the threads both times. This is a arp bolt.
Next I pulled the intake to find a ton of oil dripping out of it. Also there was oil in the throttle body and air bridge. Now I am doin a catch can. Seems like since I went with a bgger cube motor, the money never stops getting tossed at it to try to get it run correctly..
I have talked to acouple of the other big cube motor vettes here, 2 427's and 1 402, all of them are also experiencing problems. One has all the same problems I am having.
Anyone else having issues with their motors...
Rant off///
No issues here after two years of running my 447. My catch can acquires some oil in it, but none in the intake. I cleaned my filter in my vararam last weekend and had the intake off and everything was dry. There are some tricks the better tuners are using in regards to breathers and catch cans that might help your problem. I think big cube motors if set-up right are very reliable set-ups.
Good luck.
