Help with LT1 manifold (Pics)
Thread Starter
Team Owner
Joined: Aug 2006
Posts: 24,125
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From: Columbia Missouri
Help with LT1 manifold (Pics)
I was digging around on my new LT1 manifold, and starting to take things off to prep it to be sent off for machine work. I ran across two things I want to clear up before I go any further.
First, is a pic of the throttle body, and four water inlet / outlet nipples. I numbered them, and was hoping someone could clear up what each is and where it goes. Use the numbers on the pic.
Next is an image of a rubber diaphragm kind of membrane I found under the throttle body head plate. It's severely warped and disfigured and I wondered if it's supposed to look like that or if it's an example of a bad gasket. What would cause it to contort like that, and is that an indication of a problem somewhere?
First, is a pic of the throttle body, and four water inlet / outlet nipples. I numbered them, and was hoping someone could clear up what each is and where it goes. Use the numbers on the pic.
Next is an image of a rubber diaphragm kind of membrane I found under the throttle body head plate. It's severely warped and disfigured and I wondered if it's supposed to look like that or if it's an example of a bad gasket. What would cause it to contort like that, and is that an indication of a problem somewhere?
Drifting
Joined: Aug 2000
Posts: 1,758
Likes: 4
From: Medford, Or
The 2 lower ports tie into the coolent system to heat up the Throttle body during cold start up. Thay can be plugged if you don't want to hassle with them. You can purchase a 4th Gen Camaro/Firebird upper hoses that will work. See picture. The upper hose provides the extra hose. The upper ports might be the heater feeds. I'm don't remember having these ports on a '95 F-body LT1.
The throttle body cover gasket will get that way due to heat and time. The computer engines due not run well with vaccum leaks. The engine must be tight.
Hope this helps.
Dan
www.vetteworksonline.com
The throttle body cover gasket will get that way due to heat and time. The computer engines due not run well with vaccum leaks. The engine must be tight.
Hope this helps.
Dan
www.vetteworksonline.com
Safety Car
Joined: Dec 2005
Posts: 4,270
Likes: 20
From: Central Michigan
The throttle body looks like the one on my TPI unit, so maybe I can help.
#1 is for PVC
#2 is fuel vapor canister
#3 & #4 are water in/out to prevent the throttle body from icing up during old weather. Heater hose connects to #3, #4 to the intake but I am not using it anymore as it kept leaking
The rubber gasket on top of the throttle body is trashed likely to heat and old age
Hope this helps out
#1 is for PVC
#2 is fuel vapor canister
#3 & #4 are water in/out to prevent the throttle body from icing up during old weather. Heater hose connects to #3, #4 to the intake but I am not using it anymore as it kept leaking
The rubber gasket on top of the throttle body is trashed likely to heat and old age
Hope this helps out
Thread Starter
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Originally Posted by 682XLR8
The throttle body looks like the one on my TPI unit, so maybe I can help.
#1 is for PVC
#2 is fuel vapor canister
#3 & #4 are water in/out to prevent the throttle body from icing up during old weather. Heater hose connects to #3, #4 to the intake but I am not using it anymore as it kept leaking
The rubber gasket on top of the throttle body is trashed likely to heat and old age
Hope this helps out
#1 is for PVC
#2 is fuel vapor canister
#3 & #4 are water in/out to prevent the throttle body from icing up during old weather. Heater hose connects to #3, #4 to the intake but I am not using it anymore as it kept leaking
The rubber gasket on top of the throttle body is trashed likely to heat and old age
Hope this helps out
Helped a lot. I think I'll cap the coolant nipples. The PCV will be run by the brake booster vac port on the side next to it, and I will likely cap that front one as well.
As far as the fuel vapor line...how would I rout it to mine? Can I cap it and not use the canister or must I adopt it somehow?
Thanks for the help everyone.
Safety Car
Joined: Apr 2004
Posts: 3,997
Likes: 1
From: WAY DEEP INSIDE AMERICO,YES YOU LIVE HERE TO!! TX
If you want to learn more than you can imagine, go hang out at
the lt1 forums.
I hung around for a year before I decided to make the swap.
When I got my motor and trans, I already knew what the lt1 problems
were, and what everything was on one.
the lt1 forums.
I hung around for a year before I decided to make the swap.
When I got my motor and trans, I already knew what the lt1 problems
were, and what everything was on one.
Thread Starter
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Originally Posted by MEGALADON
If you want to learn more than you can imagine, go hang out at
the lt1 forums.
I hung around for a year before I decided to make the swap.
When I got my motor and trans, I already knew what the lt1 problems
were, and what everything was on one.
the lt1 forums.
I hung around for a year before I decided to make the swap.
When I got my motor and trans, I already knew what the lt1 problems
were, and what everything was on one.
Can you suggest a good LT1 forum? I'm a member of ThirdGen.org. Is that a good place to learn of these manifolds?
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Safety Car
Joined: Apr 2004
Posts: 3,997
Likes: 1
From: WAY DEEP INSIDE AMERICO,YES YOU LIVE HERE TO!! TX
Originally Posted by Durango_boy
Can you suggest a good LT1 forum? I'm a member of ThirdGen.org. Is that a good place to learn of these manifolds?
www.camaroz28.com
just look for the the lt1/lt4 sections.
third gen is only good for thirdgen models.
Thread Starter
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Originally Posted by MEGALADON
www.ls1tech.com
www.camaroz28.com
just look for the the lt1/lt4 sections.
third gen is only good for thirdgen models.
www.camaroz28.com
just look for the the lt1/lt4 sections.
third gen is only good for thirdgen models.
Thanks MEG. I just signed up at LS1TECH and will start digging there as well. Thanks so much for those links.
Safety Car
Joined: Dec 2005
Posts: 4,270
Likes: 20
From: Central Michigan
Originally Posted by Durango_boy
Helped a lot. I think I'll cap the coolant nipples. The PCV will be run by the brake booster vac port on the side next to it, and I will likely cap that front one as well.
As far as the fuel vapor line...how would I rout it to mine? Can I cap it and not use the canister or must I adopt it somehow?
Thanks for the help everyone.
As far as the fuel vapor line...how would I rout it to mine? Can I cap it and not use the canister or must I adopt it somehow?
Thanks for the help everyone.
If you'd rather use it, track down which line to your existing canister is the vacuum supply. The LT1 links mentioned earlier should have the right info
Thread Starter
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Originally Posted by 682XLR8
If you are having the computer reworked and are doing a smog-delete, you probably won't need the vapor line.
If you'd rather use it, track down which line to your existing canister is the vacuum supply. The LT1 links mentioned earlier should have the right info
If you'd rather use it, track down which line to your existing canister is the vacuum supply. The LT1 links mentioned earlier should have the right info
I'd rather not use the vapor canister. If I delete that part of the manifold, can I remove the can from the car altogther?
Safety Car
Joined: Dec 2005
Posts: 4,270
Likes: 20
From: Central Michigan
Originally Posted by Durango_boy
I'd rather not use the vapor canister. If I delete that part of the manifold, can I remove the can from the car altogther?
But I guess I just did
Thread Starter
Team Owner
Joined: Aug 2006
Posts: 24,125
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From: Columbia Missouri
Originally Posted by 682XLR8
As it's against federal law to remove any part of the emissions system, I can't legally say "Yes, you can"
But I guess I just did
But I guess I just did
What if it was already removed...would I have to install it for it to operate properly?
Safety Car
Joined: Dec 2005
Posts: 4,270
Likes: 20
From: Central Michigan
If your reprogramming the computer for no smog, then no, you won't need it.
On my TPI for example I have to run smog(84 pick-up), and the computer operates a small valve to allow gas vapor to be sucked into the motor. If the valve is left unplugged, or if there is a sensor of some kind to let the computer know there is vacuum present(likely the case on the OBD II computer systems), the computer will throw a trouble code
On my TPI for example I have to run smog(84 pick-up), and the computer operates a small valve to allow gas vapor to be sucked into the motor. If the valve is left unplugged, or if there is a sensor of some kind to let the computer know there is vacuum present(likely the case on the OBD II computer systems), the computer will throw a trouble code
Thread Starter
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Originally Posted by 682XLR8
If your reprogramming the computer for no smog, then no, you won't need it.
On my TPI for example I have to run smog(84 pick-up), and the computer operates a small valve to allow gas vapor to be sucked into the motor. If the valve is left unplugged, or if there is a sensor of some kind to let the computer know there is vacuum present(likely the case on the OBD II computer systems), the computer will throw a trouble code
On my TPI for example I have to run smog(84 pick-up), and the computer operates a small valve to allow gas vapor to be sucked into the motor. If the valve is left unplugged, or if there is a sensor of some kind to let the computer know there is vacuum present(likely the case on the OBD II computer systems), the computer will throw a trouble code
Yeah, the guy doing my computer is gonna install OBD1 and delete anything I don't want or need. I guess fuel vapor will be one of them. Thanks for the info.
