How to build a top mount manifold with minimal warpage
 

1. build your collector. i don't have any pics of building my collector, but space is sometimes an issue with top mounts so i decided to go with something a little more unconventional.
2. place your collector where you want it in relation to the head flange and start making your first runner. i decided to go with runner #3 since i knew it would be the most difficult to route.
3. tack it all together and then weld the runner, but not the pipe joining the runner to the head flange.
http://i47.photobucket.com/albums/f1...h/DSC05817.jpg
http://i47.photobucket.com/albums/f1...h/DSC05820.jpg
http://i47.photobucket.com/albums/f1...h/DSC05819.jpg
http://i47.photobucket.com/albums/f1...h/DSC05818.jpg

4. do the same for each of the remaining runners.

http://i47.photobucket.com/albums/f1...h/DSC05822.jpg
http://i47.photobucket.com/albums/f1...h/DSC05823.jpg
http://i47.photobucket.com/albums/f1...h/DSC05824.jpg

next runner:

http://i47.photobucket.com/albums/f1...h/DSC05883.jpg
http://i47.photobucket.com/albums/f1...h/DSC05884.jpg
http://i47.photobucket.com/albums/f1...h/DSC05885.jpg

5. once you have the runners all welded, bolt the head flange to a thick plate or head that isn't being used. i use a 2"x3" piece of steel that i drilled and tapped the head flange bolt pattern into to prevent warping.
6. weld the insides of the pipe to head flange seams to help prevent cracking.

finished product:
http://i47.photobucket.com/albums/f1...h/DSC06185.jpg
http://i47.photobucket.com/albums/f1...h/DSC06187.jpg
http://i47.photobucket.com/albums/f1...h/DSC06186.jpg
http://i47.photobucket.com/albums/f1...h/DSC06188.jpg
http://i47.photobucket.com/albums/f1...h/DSC06195.jpg
http://i47.photobucket.com/albums/f1...h/DSC06194.jpg

you can see there is a little bit of warp, but not much.

http://i47.photobucket.com/albums/f1...h/DSC06193.jpg

the external wg will go on afterwards.

Re: How to build a top mount manifold with minimal warpage
 

damn thats nice, when i get my 240sx, you have to help me out on my topmount, but that will be after winter. but damn that some nice work

Re: How to build a top mount manifold with minimal warpage
 

Looks sweet. U every going to sell flanges again?

Re: How to build a top mount manifold with minimal warpage
 

I have never had an issue with any warp building a top mount. Do you completely bolt the head flange down while welding it on? I always bolt it down to my jig plate very tight using all the mounting holes.

Re: How to build a top mount manifold with minimal warpage
 

yep, every hole gets a bolt. jig plate is 2" thick.

Re: How to build a top mount manifold with minimal warpage
 

I build #2 first, then #1, then #4, and then #3. But the design is different.

http://www.we-todd-did-racing.com/we...ZkMzF5NTQx.jpg

http://www.we-todd-did-racing.com/we...ZkMzF5NTQx.jpg

Re: How to build a top mount manifold with minimal warpage
 

CS: Are you selling a coule manis on Ebay or is someone ripping off your pics????

Re: How to build a top mount manifold with minimal warpage
 

I have the b series top mount I just made up there cheap. I need to pay off my new welder so what I ever I build needs to go fast to get it paid off.

Re: How to build a top mount manifold with minimal warpage
 

\
Where do you get your merge collectors.. and if you build em, how much for a t4 sch 40 one shipped to 98107??? That one is clean as ----....

Re: How to build a top mount manifold with minimal warpage
 

Yeah I make them myself. They take forever to cut on my band saw. I don't sell them seperate. You wouldn't want to pay what I would have to charge... They the majority of my time build the manifold.

Re: How to build a top mount manifold with minimal warpage
 

KTHX....

Re: How to build a top mount manifold with minimal warpage
 

I believe BMCrace.com carries merge collectors. Email the guy at BMCrace he has some.

Re: How to build a top mount manifold with minimal warpage
 

You guys make it look so easy. If I only had a bigger engine bay.

Randy

Re: How to build a top mount manifold with minimal warpage
 

sorta off topic sorta not... but how do you guys do the welds right before the collector. (the welds that connect the runners to the collect) from looking it seems you can get on the inside :l is there a trick i am not understanding? you probly could get an arc there but id have no accuracy

Re: How to build a top mount manifold with minimal warpage
 

So what size filler do you use? what kind? also what gas because my welding suppley store said i'm not supose to use 100% argon on stainless but i'm confused here? also what do you use to clean the metel befor finish welding is done?

thanks matt

Re: How to build a top mount manifold with minimal warpage
 

the trick is this, you do one runner at a time, so that the first 3 are pretty easy to get to. the 4th one is a little tricky, but every welder knows the tricks of the trade, they either learn them the hard way or the easy way. So those tricks include a few things, flexible head on the torch, different cup sizes, extending the tungsten out a bit further and playing with the gas settings. Those are a the most common things done to weld in tight spaces. hope this helps.

Very solid write up Aaron, very nice manifold as well. I just wanted to add that whenever your welding any part of a manifold that is connected to the head flange, you should always have it clamped down. I say this for two reason, 1) the heat alone from the torch can cause the head flange to warp, 2) the fact that your welding something that will eventually pull in and tighten up also pulls on the pipe that is connected to the head flange and that causes a stress point and a better chance of warping.

Re: How to build a top mount manifold with minimal warpage
 

They were probably talking about mig welding, it is common practice to add a co2 mix with argon for heat purposes. We usually clean metal a wire wheel first, then acetone and a wire brush between welds. I will leave the other two questions for aaron, because they directed to him.
Sorry for threadjacking aaron, its all you from here.

Re: How to build a top mount manifold with minimal warpage
 

sweeet writup. Fully miged mild steel top mount commin eventually! :P

Re: How to build a top mount manifold with minimal warpage
 

Actually I tack them all on in the correct position in multiple areas around each one. Then I weld them. I do all 4 at the same time. Usually if you do one at a time it will pull the others out of position.

Re: How to build a top mount manifold with minimal warpage
 

i've noticed that too, that is why i left them tacked to the head. a lot of people break them from the flange and the collector and weld them off the manifold, but in my experience they never line up again when you go to put it back together.

i use 100% argon for all tig welding. a ss or brass wire brush can be used for cleaning. i use 1/16" 309L filler for the complete manifold.

Re: How to build a top mount manifold with minimal warpage
 

great write up and awesome work Aaron!! Wondering if you are still doing the flanges and stainless material? I need some straight pipe and t's - flanges wouldn't hurt either - since your in Canada I wouldn't have to pay for customs. Let me know.

EJ

Re: How to build a top mount manifold with minimal warpage
 

Same here, never lines up right if you welder everything off the flanges.

Re: How to build a top mount manifold with minimal warpage
 

You are 100% correct, i always tack everything at least 4 places before beginning to weld. You are also right, if you have a 4th runner made and then weld the other three, the 4th piece wouldnt line up. However in our case, we usually dont even start the next runner until everything else is welded, so we then make sure it lines up accordingly. They need to invent some cheap metal that doesnt warp ::)

Re: How to build a top mount manifold with minimal warpage
 

they should huh. :D

Re: How to build a top mount manifold with minimal warpage
 

i think you guys are missing the point behind this writeup, i did one runner tacked it, then welded it, then started the next runner and so on.

Re: How to build a top mount manifold with minimal warpage
 

stick it!

Re: How to build a top mount manifold with minimal warpage
 

huh?

Re: How to build a top mount manifold with minimal warpage
 

i means this thread ;D