obx headers

[mopar3.0]

hey offer them for the stealth sohc 3.0 any one know if they make any gains, i think i might order a set this winter and make them fit, try and rerout under the tranny abd proble is a remote mount oil filter

[Ondonti]

going to need to modify the flanges or reflange them because the stealth motor sits backwards from ours...

[mopar3.0]

dam i forgot about that,

i wounder about these with some new flanges
and some pipe work ,il have to measure the spacing of the exhaust ports on the 3.8.

Pontiac Performance Racing Products for International Sales from SSAutochrome Inc.

[mightymulhern]

SSAutoChrome is like the Harbor Freight of car parts. Run Away. Some of the ways they word their eBay auctions shows that they don't even understand what they are selling. I know Brent was also "pleased" with the turbo he bought from them that turned out to be something totally different than advertised.

SSAC bashing aside, there are a few problems with the set of headers here. First up, 1.75" primaries are WAY too big for this engine. This is coming from the guy who did a prototype with 1.75" ones and failed to head the bigger isn't better warning in every header book you will find. If I had it to do over I'd be looking at 1 5/8 as the max and potentially necking down to 1 1/2". Second, the rear header would hit the firewall in its current configuration. You might be able to add some more bends but that might be harder than just fabbing them from scratch... Third, it's likely that the front header is going to be too tall and hit the radiator. For sure you would have to move the fan to the opposite side of the radiator (which has been done).

If you have the ability to weld it would almost certainly be cheaper and less irritating to just buy some tubing, buy some flanges, and make your own. Things to take note of are the spark plug holes, the frame down behind the engine, the oil filter, starter, half shaft, and ground clearance. All make routing a real nightmare. Under engine routing is nearly impossible without frame modification unless you don't mind 1.5" of ground clearnace... and then it's just a bad idea.

I don't know if this helps or not but I'd hate to see anyone run off and buy a set of headers to butcher, buy a set of Mitsu based headers thinking there is any prayer that they will work, or have any illusion that fabbing headers on a 3.0 is a quick & easy job. If there was a quick and easy solution, Ed and I would be selling sets of them right now.

[mopar3.0]

i only have about 2 inches of clerance now at it is

what happned to the first set you fabbed up?

[lookin]

Well you can all go ahead and laugh at me again, but I got very good results.

The stock exhaust manifolds, are not so bad at all, and having mine heat stop coated made them flow a lot better than they did uncoated.

I have 2.5 inch pipes, a catco hi-flow verter, with a magnaflow center in center out straight shot muffler.

If you live in the Fort Wayne area, then let me show you, what I mean by good results.

[RoadWarrior222]

I ran some numbers for what I wanted out of headers and was getting 1.25-1.5 inch primary diameter.

[mightymulhern]

Quote:

Originally Posted by RoadWarrior222 I ran some numbers for what I wanted out of headers and was getting 1.25-1.5 inch primary diameter.

That sounds about like the math I ran awhile back. ...the difficulty is that the exhaust ports are a hair over 1.5" so whatever you do needs to be expanded at the port and necked down. Well that or use an insert for the port. Either way you need to do some kind of transition so you don't have a smaller pipe than port with a step impeding flow.

[mightymulhern]

Quote:

Originally Posted by mopar3.0 i only have about 2 inches of clerance now at it is what happned to the first set you fabbed up?

Here's the pics:
Current Projects

I fabbed these awhile back, put the car on the dyne, and was not impressed by the power shown. ...the seat of the pants -o- meter didn't really yield any definitive gain either. Discouraged after that, the prototype sat in my garage and rusted for a couple years (took them off because they were LOUD). Now we're talking about putting them on Ed's van on top of his ported heads to see if they start to yield anything on his van.

I've contemplated a second round prototype but the time involved has kept me from it. I've got another massive multi-year project that I started that I need to finish first. The next prototype would use much smaller primaries if I ever do it.

[mopar3.0]

you should just sell em to me, i might make more use of them with the 10.1 pistons and big cams

[Ondonti]

i want to see them on eds van.

[mopar3.0]

shut up brent lol
im willing to spend good money here lol

[mopar3.0]

lookie what i found in the 3.0 list,


eererere

[DustyR/T]

dang that's crazy...are they for sale?

[RoadWarrior222]

Quote:

Originally Posted by mopar3.0 lookie what i found in the 3.0 list, eererere

Cools stuffs, although he makes it look almost as involved as fabbing from scratch.

Edit: Read that through twice now... I'm getting ideas about it... I'm thinking that a minivan doesn't quite have the same space issues as that P-body, and if one already has or is willing to do intake mods, and batt relocation, then it might almost be bolt-on.

So ghetto method on a van, lets presume you get one with a flat flange on it, fit looks close enough that you could port the heads and flange to match, drill holes where it needs it, and use strapping bars across where it doesn't have the holes to bolt it to the head directly. Some means of positive location is desireable so it won't slip, it will have a hole drilled thru the flange at one end, need something at the other end, maybe tack down the strapping bar. Assuming we can make room for it front and back, then cut the mid pipe to make the right angle for joining, one bend welded in there, or u-clamped flex joint for the truly ghetto... You're going high and wide around the side, so maybe won't have the coolant pipe fitment issues, if you've got 1 inch spacers on the plenum it might clear TB well enough..... anyhoo, looks like it could be ghetto rigged easier if you move other stuff around ..... not sure it's worth the trouble to do it the other way, 'coz you're taking what might be a marginal design for it's original application and messing it around more, with all that measure and cut to fit stuff, you'd be better off calculating it all from scratch and building something designed to the right numbers.