Sealing the intake...
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
Thanks, didn't use RTV. I used The Right Stuff which sets up in just a short time.
Someone told me it was best to wait to crank it. I was wondering what the general consensus was. I can't see how a gasket would seal any better if it sat for that long before being cranked.
Someone told me it was best to wait to crank it. I was wondering what the general consensus was. I can't see how a gasket would seal any better if it sat for that long before being cranked.
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
Race Director
Joined: Jan 2002
Posts: 12,263
Likes: 86
From: O'Fallon Missouri
Mike, you have a great running car. Once you get this intake situation solved why don't you take a step back and enjoy the fruit of your labors for a while. Just drive the car and try to quit overthinking the small details. The more your drive with the same combo the PCM will learn and some of the small tuning issues will go away.
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
Mike, you have a great running car. Once you get this intake situation solved why don't you take a step back and enjoy the fruit of your labors for a while. Just drive the car and try to quit overthinking the small details. The more your drive with the same combo the PCM will learn and some of the small tuning issues will go away.
I broke a wire in the TPS plug so I'm waiting on a pigtail, it'll be here in the morning. I think I will drive it a while and just see what transpires after I get that fixed. thanks for the advice
Race Director
Joined: Jan 2002
Posts: 12,263
Likes: 86
From: O'Fallon Missouri
Are you putting any sealant on the intake gasket, or installing dry? I read where some recommend smearing a small film of sealant on the gasket, to me this could cause a sealing problem by uneven sealant. I always install my LT1 intake gaskets dry and have never had a sealing problem.
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Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
Are you putting any sealant on the intake gasket, or installing dry? I read where some recommend smearing a small film of sealant on the gasket, to me this could cause a sealing problem by uneven sealant. I always install my LT1 intake gaskets dry and have never had a sealing problem.
I just checked the Edelbrock to see if it was straight where the port flanges are. NOT! There's a slight hump in the middle where the PCV grommet goes. The right side is flat. Not much but it's there. Maybe this one in there now is that way to. My old intake is very flat on both sides but not ported.
Safety Car
Joined: Sep 2000
Posts: 3,524
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From: Hinckley Ohio
Thanks, didn't use RTV. I used The Right Stuff which sets up in just a short time.
Someone told me it was best to wait to crank it. I was wondering what the general consensus was. I can't see how a gasket would seal any better if it sat for that long before being cranked.
Someone told me it was best to wait to crank it. I was wondering what the general consensus was. I can't see how a gasket would seal any better if it sat for that long before being cranked.
Actuallly it seems like what you did should be ok, but......Permatex appears to only recommend RTV Sealant 82180 for sealing of ends of intake manifolds, which is what GM & Edelbrock specify....."Right Stuff" does not list end seals on intake manifolds as an applicationhttp://www.permatex.com/documents/Ga...erSelector.pdf
..appears there might be more of a difference than just curing times
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
Actuallly it seems like what you did should be ok, but......Permatex appears to only recommend RTV Sealant 82180 for sealing of ends of intake manifolds, which is what GM & Edelbrock specify....."Right Stuff" does not list end seals on intake manifolds as an applicationhttp://www.permatex.com/documents/Ga...erSelector.pdf
..appears there might be more of a difference than just curing times
Le Mans Master
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Last year when I installed the wrong intake gasket, I went back and disassembled the intake 3-4 days later and the RTV was not cured.
my 2 cents
my 2 cents
Le Mans Master
Joined: Dec 2002
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From: Seattle Area WA
I use the Right Stuff too. One time I did need to fire the motor within about 4 hours of bolting the intake on because I had to get it out of the garage. Everything was fine. I didn't let it run long but it sealed and ran fine until the day I tore it apart.
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
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From: Sandhills of North Carolina
I fired it up today and sprayed carb cleaner around the entire intake and no change in rpm. If it's leaking it's in the lifter valley. Idle is decent so I doubt that is happening. Sitting overnight seems to have helped it.
Thanks for all the responses guys.
Thanks for all the responses guys.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
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From: Kempner Texas
I fire my engines as soon as I finish bolting everything back together. I've never let it sit for 24 hours or any other length of time.
Another point, I always install the intake BEFORE the sensor safe silicone sealant skins over. I want it to still be wet in order to fill in nicks, etc. as it's compressed.
One more, I always apply a thin layer of sealant on BOTH SIDES of the intake gaskets. Pressure from the 35 lb/ft of bolt torque flattens it out. This is shown in one of the Chevy build manuals I have.
And again, I go over my intake manifold bolts numerous times until they all HOLD the torque setting. This may take hours while the gaskets take a compression set.
Lastly, I use a 3/8" bead on each China Wall, as opposed to the 1/4" bead often cited. I also dimple the China Wall areas on BOTH the block and the underside of the intake. ShoeBox - a guru on some other Forums (but, alas, not here) - does that too. "Old Racer's" stuff; and since I'm an "OLD Racer", well, there you go.
I post a detailed STICKY on LS1LT1.Com on the LT1 TECH board for those who like to read. My stuff doesn't leak - I don't play that, LOL
Jake
Another point, I always install the intake BEFORE the sensor safe silicone sealant skins over. I want it to still be wet in order to fill in nicks, etc. as it's compressed.
One more, I always apply a thin layer of sealant on BOTH SIDES of the intake gaskets. Pressure from the 35 lb/ft of bolt torque flattens it out. This is shown in one of the Chevy build manuals I have.
And again, I go over my intake manifold bolts numerous times until they all HOLD the torque setting. This may take hours while the gaskets take a compression set.
Lastly, I use a 3/8" bead on each China Wall, as opposed to the 1/4" bead often cited. I also dimple the China Wall areas on BOTH the block and the underside of the intake. ShoeBox - a guru on some other Forums (but, alas, not here) - does that too. "Old Racer's" stuff; and since I'm an "OLD Racer", well, there you go.
I post a detailed STICKY on LS1LT1.Com on the LT1 TECH board for those who like to read. My stuff doesn't leak - I don't play that, LOL
Jake