LS6 Intake Swap Compatibility
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Try this:
Lay some copier paper over the things on the top of the valley cover. Your are covering anything that the manifold can come in contact with. Make sure that you over lap the areas where the crossover pipes bolt to.
Lay the manifold straight down in place and apply pressure on it and rock it. Remove the manifold and see if there are any marks on the paper. That will tell you where any contact points are.
See if that helps.
Bill
Lay some copier paper over the things on the top of the valley cover. Your are covering anything that the manifold can come in contact with. Make sure that you over lap the areas where the crossover pipes bolt to.
Lay the manifold straight down in place and apply pressure on it and rock it. Remove the manifold and see if there are any marks on the paper. That will tell you where any contact points are.
See if that helps.
Bill
Thread Starter
Drifting
Joined: Mar 2000
Posts: 1,956
Likes: 135
From: Maryland
This afternoon I tried what I think Bill's suggesting. I cut some paper and taped it to the bottom of the manifold. I colored the tops of the pipes with a sharpie, dropped on the manifold and rocked. There was evidence of slight contact with a pipe and I hammered a little flat spot on that section of pipe. A second check confirmed no contact. Just for another try, I colored the tops of the pipes with with a white grease pencil and dropped on the manifold (without the paper), still no contact was indicated.
Also tried removing the knock sensor wires and no change.
Nuke, do you know if you were rocking on the pipes or was it something else that you couldn't find? At 20 in-lbs, I couldn't squeeze my thinnest feeler gauge in anywhere but of course there's no way to check the bottom.
Hopefully, this isn't the reason I got such a bargain on the manifold.
Thanks!
Also tried removing the knock sensor wires and no change.
Nuke, do you know if you were rocking on the pipes or was it something else that you couldn't find? At 20 in-lbs, I couldn't squeeze my thinnest feeler gauge in anywhere but of course there's no way to check the bottom.
Hopefully, this isn't the reason I got such a bargain on the manifold.
Thanks!
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Still analysing your issue.. If the maniflod doesnt contact anything that keeps if from seating,, like "NukeC5" stated,, its NYLON and when you bolt it inplace, it will lay in like its suppose to.
If it were me, I would make sure that there were new O ring seals on that puppy.
If it were me, I would make sure that there were new O ring seals on that puppy.
Thread Starter
Drifting
Joined: Mar 2000
Posts: 1,956
Likes: 135
From: Maryland
Yup, have a new o-ring / foam kit!!
I was checking the fit without any o-rings.
Sounds like there won't be a problem. I'll check the length of the bosses then toss the intake in a box and move on to the next part of the fun (remove radiator, exhaust manifolds, tunnel plate, and change clutch fluid while waiting on all the goodies to show up).
I was checking the fit without any o-rings.
Sounds like there won't be a problem. I'll check the length of the bosses then toss the intake in a box and move on to the next part of the fun (remove radiator, exhaust manifolds, tunnel plate, and change clutch fluid while waiting on all the goodies to show up).
Melting Slicks
Joined: Jun 2012
Posts: 3,163
Likes: 6
From: Oceanside California
After doing both the LS6 swap and now FAST I think it is common for the intakes to have warpage from the factory. I had rocking both times. Scary both times like I said, but both have work out perfect. No marks on the underside of the LS6 I removed from anything that had been rubbing while installed. I think you are good to go.
Thread Starter
Drifting
Joined: Mar 2000
Posts: 1,956
Likes: 135
From: Maryland
I put a straight edge across the bolt bosses this morning. Sure enough, the back two on both sides are lower than the rest. Tried it on the original manifold and they're all over the place as well.
Looks like its good to go!
Thanks
Looks like its good to go!
Thanks
Le Mans Master
Joined: Sep 2003
Posts: 6,276
Likes: 227
From: Farmington CT
Cruise-In VII Veteran
97-00 are the only motors to use the knock sensor harness with the green clips for the front'back coolant spider
did you remove the clips?
and the the foam/harness surround near the aft needs to be orientated correctly, most likely this is where you are getting the 'rocking' from
did you remove the clips?
and the the foam/harness surround near the aft needs to be orientated correctly, most likely this is where you are getting the 'rocking' from
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Thread Starter
Drifting
Joined: Mar 2000
Posts: 1,956
Likes: 135
From: Maryland
All knock sensor wires were removed while fitting. Issue was the bolt bosses.
Green clips were removed as I didn't want something that was a larger diameter than the pipes. Good to hear they're not on the later motors.
Don't want to turn this into a build thread but .... So far, exhaust manifolds off, intake off, radiator out, water pump off, tunnel plate off. Hopefully will find ATE brake fluid tomorrow so I can change the clutch fluid and put the tunnel back on. Probably drop the rack tomorrow as well.
Green clips were removed as I didn't want something that was a larger diameter than the pipes. Good to hear they're not on the later motors.
Don't want to turn this into a build thread but .... So far, exhaust manifolds off, intake off, radiator out, water pump off, tunnel plate off. Hopefully will find ATE brake fluid tomorrow so I can change the clutch fluid and put the tunnel back on. Probably drop the rack tomorrow as well.