Best exhaust manifolds for LS engine in GM a-body?
02-07-2011, 11:31 AM
#21
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Exhaust manifolds on Chevelle I installed the truck motor and tried to use the truck manifolds but the drivers side hit the frame. I swapped them for the F-Body manifolds and they fit perfect. I have the factory steering box, factory steering shaft etc. I also bought some cut off flanges off eBay and had the exhaust shop weld my down pipes to them. I also bought the M18 plug from a hardware store and plugged the drivers side O2 hole. I had my O2's ran back in the down pipes that way if I decide to run headers I don't have to make any modifications in that area. Not to mention there was no way to put a sensor in the drivers side. I'll have to take a pic of the clearance.
02-07-2011, 12:14 PM
#22
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I tried the LS2 Corvette, C5 ZO6, G8 and GTO manifolds, since I had them all on the shelf in the shop. None of them worked. The GTO manifold turned out and hit the frame, while both the ZO6 and LS2 Corvette manifolds hit the crossmember. The G8 Manifold would go on, but the pipe flange was hard on the frame when installed. I was sure that a set of F body manifolds would clear, but finally just ended up putting a set of Edelbrock stainless headers on it.
Regards, John McGraw
Regards, John McGraw
My experience getting the Camaro manifolds to work may be due to the fact that I made my own mounts. I think I may have the motor tweaked a tiny bit towards the drivers side to help with the pass side flange hitting. Even so, I still needed to trim it a bit and have to change the location of the drivers side sensor.
Gene
02-07-2011, 12:25 PM
#23
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The Edelbrock headers are shorties right? Not long tube? Did you go away from the manifolds to make other hp upgrades? I may consider going to headers but from everything I read says the hp advantages are in long tubes.
Has anyone here used late model F-body headers in this conversion? Is this a possible fit solution or more trouble?
02-07-2011, 12:39 PM
#24
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I've been wondering the same thing.... I was looking at swapping some 4th gen long tube headers into the Chevelle in place of my 4th gen manifolds. Anyone completed that?
02-07-2011, 06:10 PM
#25
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I used the Edelbrock long tube headers. They were tight, but they fit fine. There ain't no getting the starter off however, without taking the headers loose!
Regards, John McGraw
Regards, John McGraw
02-07-2011, 06:18 PM
#26
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Inquiring minds want to know....were they F-body headers or LS swap headers? Where were they tight?
02-07-2011, 11:06 PM
#27
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They were the LS1 swap headers not F body. They were only tight around the passenger side rear bushing mount for the lower control arm. I had to jack the engine up a little to get the header past this point, but once it passed this point the clearance was actually pretty good. If you want to remove the starter, you have to take the bolts loose at the head and allow the header to drop down a little to get the starter out. You can not even get a socket on the outboard starter bolt, with the headers bolted up.
My engine is set pretty low and pretty far back, so I am sure that this is some of the reason that they are so tight getting on. If the engine sat 2" further up, I believe the headers would slip right in.
Regards, John McGraw
My engine is set pretty low and pretty far back, so I am sure that this is some of the reason that they are so tight getting on. If the engine sat 2" further up, I believe the headers would slip right in.
Regards, John McGraw
02-08-2011, 12:13 PM
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They were the LS1 swap headers not F body. They were only tight around the passenger side rear bushing mount for the lower control arm. I had to jack the engine up a little to get the header past this point, but once it passed this point the clearance was actually pretty good. If you want to remove the starter, you have to take the bolts loose at the head and allow the header to drop down a little to get the starter out. You can not even get a socket on the outboard starter bolt, with the headers bolted up.
My engine is set pretty low and pretty far back, so I am sure that this is some of the reason that they are so tight getting on. If the engine sat 2" further up, I believe the headers would slip right in.
Regards, John McGraw
My engine is set pretty low and pretty far back, so I am sure that this is some of the reason that they are so tight getting on. If the engine sat 2" further up, I believe the headers would slip right in.
Regards, John McGraw
Thanks a ton, Gene
02-08-2011, 03:54 PM
#32
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I'm in the middle of my swap right now. I have an 02 Camaro LS1 6 speed setting in the my 64 Skylark (same as 66 Chevelle). The stock Camaro manifolds fit with one problem; the oxygen sensor on the drivers side needs to be fitted elsewhere. I'll drill and tap a new hole for it unless I go with some long tube headers. I did need a tiny bit of grinding on the PS flange. The original cat pipes hook up with plenty of clearance. Made my own motor mounts.
I am using the Camaro column though so I can't say for sure if it would be an issue with the original column, I don't think so though.
Without seeing the article mentioned, was there much difference in the GTO manifolds verses the Camaro manifolds I'm using? I guess one question is how much hp gains can be expected from long tube headers over stock GTO or Camaro manifolds?
I am using the Camaro column though so I can't say for sure if it would be an issue with the original column, I don't think so though.
Without seeing the article mentioned, was there much difference in the GTO manifolds verses the Camaro manifolds I'm using? I guess one question is how much hp gains can be expected from long tube headers over stock GTO or Camaro manifolds?
In my case the OS in the drivers side was busted when I recieved my pullout engine. I gutted the OS keeping only the threaded flange. I then stuck a smaller bolt in it and welded it in the OS flange ground it smooth and used it for a plug for The drivers manifold. I then located the OS in the new exhaust pipe just after the manifold.
Skylark for reference this is mine with stock column shaft. Quite a bit of space between it and the manifold.
Last edited by rockytopper; 02-08-2011 at 03:59 PM.
02-08-2011, 08:15 PM
#33
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I have 2002 f-body mainifolds and had the exact issues as outlined above.
In my case the OS in the drivers side was busted when I recieved my pullout engine. I gutted the OS keeping only the threaded flange. I then stuck a smaller bolt in it and welded it in the OS flange ground it smooth and used it for a plug for The drivers manifold. I then located the OS in the new exhaust pipe just after the manifold.
Skylark for reference this is mine with stock column shaft. Quite a bit of space between it and the manifold.
In my case the OS in the drivers side was busted when I recieved my pullout engine. I gutted the OS keeping only the threaded flange. I then stuck a smaller bolt in it and welded it in the OS flange ground it smooth and used it for a plug for The drivers manifold. I then located the OS in the new exhaust pipe just after the manifold.
Skylark for reference this is mine with stock column shaft. Quite a bit of space between it and the manifold.
What it comes down to is I'm wondering if long tube headers stick out futher than the stock LS1 manifold, if they do I will have interference issues if I want to go that route.
02-12-2011, 08:31 AM
#37
I have a 67chevelle convt.with ls1,brp mounts.Engine is appx.1-1.5 inches off the firewall on passenger side head.Fbody manifolds(98-02) fit like they were made for it.Couldnt ask for a better fit.I put the oxegen sensors in the head pipes,the driverside oxegen sensor is the only thing that wont clear as is.My car is a stock motored cruiser so I am very happy with the factory manifolds,they are a lot less hassel.If I were doing a cam and heads, more performance orintated setup I would do the headers.The 2010 manifolds look really good ,like little shorty headers.If they will fit they would be a great option.
Last edited by SUPERBOOST; 02-12-2011 at 08:36 AM.
02-12-2011, 09:11 AM
#38
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Ditto on the F-body manifolds in my 64 Skylark. Good fit except for DS sensor.
Here a link to a great article that talks about LS changes and why. It gets into the exhaust manifold flow too. Great reading,
http://www.cadillacfaq.com/faq/answe...0of%20power%22
Here a link to a great article that talks about LS changes and why. It gets into the exhaust manifold flow too. Great reading,
http://www.cadillacfaq.com/faq/answe...0of%20power%22
02-17-2011, 12:36 PM
#39
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Measurment Please? Can anyone take a measurement how far the rear two tubes stick out from the LS1 head mounting surface on a pair of long tube headers?
I have a very different set up in my 64 as I modified the firewall to fit the LS1 steering column and pedal assembly. One of my steering u-joints is quite close to the LS1 exhaust mainifold. I'm wondering if I will have an interference issue with going to long tube headers.
Thanks!!!!!!
I have a very different set up in my 64 as I modified the firewall to fit the LS1 steering column and pedal assembly. One of my steering u-joints is quite close to the LS1 exhaust mainifold. I'm wondering if I will have an interference issue with going to long tube headers.
Thanks!!!!!!
