As a lot of you have already seen there is a really popular manifold selling on Ebay lately for anywhere from$175 up.
The two I have seen and more than one I have heard about has had problems with the bolt holes on the wastegate flange being off, and off badly.
In one case it was off on the exhaust flange as well and required oversizing the holes with a larger drillbit.
One hole had to be slotted a little with a carbide cutter even after that.
For any of you that have never drilled and tapped stainless let me point out up front that you don't even want to try a cheap bit and especially don't break off a cheap tap in it. Even with a good tap you will need to work carefully and go ever so slightly back and forth a little more each time and use a light oil. Use a coolant on your drill bits or you will overheat and ruin them quick.

The way I fixed one was by threading a stainless bolt into a hole (on the wastegate flange) that was about an 1/8" off.
I couldn't find my red locktite so I dinged the threads on the bolt a little so it would be really locked in and then ground it flush. I bolted the spacer plate from the HKS wastegate in the 3 good holes using short screws and marked a fresh hole with a drift punch.
Once I drilled and tapped it you could see a moon shaped remnant from the filler bolt. I could have slotted the hole a bit but I would have had to have disassembled the entire wastegate to put a longer bolt so it would go through the flange.
Another thing to consider is that there is at least one hole that is too close to the tube to get a nut on.

I hope this helps some of you. I still would not hesitate to pick one of these up for $175 even with the work required to get it to work. And you may get lucky and not have to go through this.

 

Oh, you need a 17/64" drillbit. (I used a 1/4", it's a 64th under and you have to go a little bit easier) The tap is a 8mm-125 thread pitch.
I don't remember what size bit I used on the exhaust flange. I would recommend laying a gasket on it and seeing how close/far they are and use good judment. Drilling a huge hole because a hole is pretty far off would be dumb. You would slot the hole with a high quality rotary cutter for a hole like that.
If you lay the gasket on and mark where the holes are off it will be a good reference if you do need to slot.

 

I'm waiting for a wastegate to check fit. Thanks for the heads-up

 

The bolt holes are symetrical so with a series of measurements (linear and diagnol) you can at least get an idea if it is off.
Obviously you do not want to try to fix it before you have the spacer plate for reference but at least you will know where you are at.
Did you get to put it on the exhaust studs to see if it fit there?
They are a great looking manifold and hopefully they get a better handle on their QA.

 

Dammit I just noticed I said "drift punch" DOH!!! I should never post anything technical before 9am I was referring to a transfer punch.
These are worth their weight in gold in situations like this. A cheap set from Harbor Freight works great. Even though these are standard sizes you can usually do a metric hole using the punch that will fit closest and just eyeball that the gap is pretty even.
Note that I am posting two links. One is for a gauge set for doing smaller holes and these are very nice as well.

http://www.harborfreight.com/cpi/cta...temnumber=3577

http://www.harborfreight.com/cpi/cta...emnumber=30320

 

and they have a set that goes to 1" for you hardcore boys

http://www.harborfreight.com/cpi/cta...emnumber=30319

 

intead of locking a stud into the old hole and grinding it flush why not try to fill it with a welder ?or will that warp the flange to much from the heat of the welds?

 

Worse yet it will create an inbalance in the hardness and the odds of breaking bits/taps is very high. If the shear strength and hardness varies the bit/tap will have more strain on the harder material. Just the uneven load will cause breakage.
I hope that makes sense to you.

 

hrm... never thought of that

 

Well I'm an expert at fuggin' things up and fixing them so I've drill and tapped a lot of mistakes and made plenty more mistakes in the process

 

damn you mean the wastegate flange might not line up either? i had to drill a lil bit off for it to fit the block, and i had to cut a small a bit off my heat shield for my motor mount so the wastegate flange wouldn't hit it... but if i have to take that damn manifold off again to drill out the holes on the wastegate flange i am gonna be pissed... this sucks man! all i know is that my turbo better fit... its a tangental divided .84 hotside,

 

The wastegate flange is most likely not right. I have not seen one that was as of yet Hopefully you are an exception. Let us know.

 

I need to get my wastegate to check!

 

the t4 flange fits without modification right???? meaning turbo to manifold flange

 

It did on these so I *think* they may have did those right.

 

Both of the flanges on the OBX that I got (which I think I'm ditching anyway) were warped pretty well. If I bolted up the turbo to fit square on one corner, I'd have a 3/16" or so gap at the opposite corner. I had to spend a little time on the belt sander to square that away. You guys notice this too?

 

When did your brain grow so big, Scally ?

I'm thinking that we might just have to make you the official Gotham Fabricator Extraordinaire

 

I think Steve has already had that idea a few times too

 

Another "heads up" on the EBAY OBX Manifold. Tha main reseller is S&SAutochrome. Now there is another seller "Hotrodheaders", who claims to have a better designed, non-cracking welds manifold. I quote from there auction:
"XS POWER JDM MANIFOLDS "

LIFETIME WARRANTY AGAINST CRACKING

( wont crack like OBX manifolds ! )

2.7MM THICK PIPES BEAT ANY OTHER MANIFOLD BY .8MM !

~ STRONGER, BETTER FLOW, BETTER WELDS ~

"

Weelllll...to make a long story short I bought an OBX from S&SAUTOCHROME and one from HOTRODHEADERS. Imagine my surprise when I process the PAYPAL Payment and guess who HOTRODHEADERS is? Thats right!!!!!! S&SAUTOCHROME. So we will soon see the differences in these manifolds. I bet they are no-label OBX's

John

 

These guys sound pretty damn shady.

 

no, the turbo did not line up either. we had to use a carbide cutter to slightly enlarge/slot two holes on the manifold. i had a spacer made and welded onto the manifold before my trip down here so the turbo i have would fit w/out hitting the lim. i have a garrett 60-1 .70 comp w/ a 1.15 div turbine housing. it was a pain in the butt to get in there in regards to clearing the a/c line that runs along the framerail but its in. now needing scalli to come and weld up the down pipe and wastegate dump for me

 

so is there a difference between the obx and the other generic brand one....which one do you guys think is better...i been trying to get the generic one 2.7mm ....

 

Ok, got the "generic" manifold from HOTRODHEADERS AKA SSAUTOCHROME. It appears at first impression to be a KNOCK-OFF of the OBX manifold. There are no gussets on the knocl-off. I will take measurements and photos later