for those who used 4th gen cast manifolds for your ls swap how did you guys work with the regular spohn tranny crossmember. this is what i am starting off with any pictures out there? of a complete set up .. catted or non catted i just need an example before hand

such as kubus build

any one? ??

Good question! At this point (before I know anything ) I'm planning on essentially duplicating the factory setup, but that really depends on where the headers come out...

did some browsing couldnt find too many people with manifolds..

but heres a non drews crossmember set up

mine is literally straight piped back under the crossmember, hammered in where it gets close. I'll find a picture or 2 of it. It's relatively low, but i live in FL so its all good

Are you using the stock k-member? With a Spohn I am taking the exhaust the stock route. If interested I hope it will be complete in 1-2 weeks

Where did you get the flanges? I haven't found the larger one yet and could use a source.

im using spohn k member.. i had those fabricated about 1/4 inch thick

I may not be anyhelp since I made my own crossmember (double hump) I made my flanges myself. I used 3/8" steel and traced out the shape. then I found the center of the hole drilled it and used that to install a bolt and used the lath to cut out the rest of the center. drill press on the smaller holes and a band saw for the shape.

I used 3" mandrel pipe all the way from the flanges to the catback

any pictures?

In order to pass the REF inspection, the cats need to be in the same location as the LSx Year you got it from. Then you build from there

my main concern right now is working around the piping as well as having a sportline srpings.

I can't find them. they reall were not good pictures anyway

I can take some pictures of my y-pipe, but it's no longer on the car. I ran factory manifolds with a stock k-member and spohn crossmember.

saleen85

that would be great..

looking for details and pic for this setup.

like to know where did you guys get the 02 bung plugs ? whats size and thread

and some good pic of how the manifolds where extended to the y-pipe. preferably stock K-member and 4l60e

Thanks

Since this topic has been bumped already I am gonna go ahead and ask if anyone knows if those flanges can be bought? I know TPI TERR said he made his but I don't know if I have the resources to make my own lol. Also, anyone ever used stock cats with the factory manifolds? I am not sure how I'm gonna mount my cats if I go aftermarket if I want to keep them close to the manifolds like the stockers.

you can buy the o2 bungs at carquest. the part number on the bag they came in is 4962. 18mm o2 sen. boss. i just welded mine on today. i will post pics this weekend.

whats did u use to plug the exisiting holes in the manifolds ?

They offer plugs for O2s as well

Talk to your local exhaust shop

I have a set of cut off flanges from a truck not sure it there the same but if some one wants them I can dig them out.

If you got a picture of them I might be interested.

The oddball flange is different from car to truck manifolds. The semi-symmetric appears the same

I have both to compare

heres a pic of where i put my 02 bungs. i still have to get a cap for the old hole. this should be temp. i am planning on running longtubes. i should get my car started in the next day or 2 . i am hoping to take it out for a couple of shakedown runs and put it up until spring. hopefully i figure out by then what i want to do with the exhaust.

Why weld a bung to the cast manifold when you can move it 6" downstream to the Y-pipe?

this is all the exhaust i am going to have for awhile. i am leaving my exhaust off until next spring. i just wanted the o2 connected while break my engine in.

Put a short section of pipe on the end of the manifolds. Open shortys/manifolds is a bad idea

That 02 is only reading 1 cylinder. On the other hand, sticking it into a shorty tube hanging off the manifold may not give you the most accurate results either, because it might get some outside air.

Why not fab up at least a y-pipe for now?

The way we used to do this on our oval track cars was put cheap spray paint on the pipe. Run a race. Wherever the paint was melted off too we would cut the pipe there and/or make a new one that same length. Old school farmer tech but they all swore it was the way to go. Dunno but thought Id mention it

Sorry it took so long and not sure if your still interested, and the oddball flange is bent any way. but hear is a pic. It looks like the gasgets are difrent to. Oh well.

As for the origanal topic I don't think you can run the exaust in the 3rd gen stock location because the oil pan is in the way of getting the exaust over there the only option seems to be running along the trans in the tunnel.

im still having leaks with my flanges that we made.
im using felpros. any of you guys have problems with felpro?
i might go pick up some gm ones.