Also some pictures show good ground clearance and some don't. i plan on lower my 91rs at least 2 inches will it matter??

 

We made some material analysis to Maximizer long tubes.Results:

Flange: Fe 74.3% Cr 15.2% Ni 3.9% Mn 5.3%
Primaries: Fe 73% Cr 14.8% Ni 1.3% Mn 9.3% Cu 1.4%
Collector: Fe 72% Cr 18% Ni 8% Mn 1.1% this was only part at headers that was aisi304
Reducer to 2.5": same material as primaries
Y-pipe 2.5"parts: same material as primaries
Y-pipe 3":same as collector(aisi304)

 

So the primaries are more like a 400 grade stainless. Interesting.

-- Joe

 

For those of us who are not metallurgists, does this have any impact on longevity, reliability, etc?

 

less chromium = less corrosion resistance. 304 stainless is 18/8 so 18% chromium, 8% nickel.

400 stainless (under 16% chromium, and less than 5% nickel) has less corrosion resistance but is more machine/weldable.

edit: I should elaborate more.

So, most 'stainless' exhaust is 409, which is 10.5-11.75% chromium, and .5% (yes 1/2) nickel.

At 14.8 and 1.3%, they are better than 409 but not as good as 304. 304 is your food grade stainless.

SLP headers for example were 409 stainless.



-- Joe

 

400 stainless is titanium stabilized ferrutuc and because of the ferrite structure it's magnetic. 3xx are austenitic steel. Chromium content on these is higher than typical 409, I think it was around 11% These chinese things will stain and get some corrosion, especially from finger smudges on them before getting hot the 1st time. That's indicative also of the lower than food grade stainless (higher grades are used for instance in food processing like mayonaise because of the acidic contents)

Still...for the price, they sure beat a rusty set of mild steel headers

 

My Dyno-wong headers showed up today. When I have time tonight I'll take 'em out of the box and measure them up to make sure they are what I want.

One thing I didn't consider, I'm running a 168 tooth flywheel with starter outboard. I hope I don't have an issue.

-- Joe

 

Dyno wong (don?)

 

Nah, Dyno-Wong (OBX) makes the chinese stainless long-tube 1 3/4 headers.

Dyno-Don makes the mild steel shorty headers.

-- Joe

 

I wont have time to play in the shop tonight, but I opened the box and checked them. Each primary measures between 1.76-1.78", so they are def 1 3/4" primaries (ebay ad said 1.5")

The flange openings are like 1.67x1.86. I'm going to double check my AFR-210 heads, but I thought they were 1.6x1.6 or something like that.

My y-merge is a lot better than the one in post #83. Looks like they may have improved a little. If you look into either end you don't get part of the other pipe intruding into the air stream.

These were under $400 shipped to my house.

Now let's see how they fit on the car.

-- Joe

 

OH the OBX things fit a 168t flywheel and bell, you will have to grind a little on the starter if you have one of those with a multi pattern mounting block. I got one to fit also in gerrutcamaro's project thread.

 

I'm eager to see the results. I've been kicking around the idea of getting these headers for a few months now. These are a 2.5" collector and Y, into a 3" single, correct?

 

The collector can be vut back up to 3 inch. Dont know about the y pipe. Wont use it

 

Are there fitment issues with the Y-Pipe that they provide? Or just poor routing?

 

I might use some of the supplied y-pipe, but.

Anyway. So for those that asked.

I removed the starter, most of the spark plugs, and my dipstick tube.

Both sides fell in (and out) from the bottom. In fact, I almost dropped one in the floor when I lowered the car back down. You don't need to remove the oil pressure sender, or the oil filter. I didn't need to grind or kit the control arms. It took me 10 minutes to remove my SLP headers (no y-pipe), and about 15 minutes to install both sides.

I do however have a fitment problem on the driver side. For some reason, the collector hits the floor pan. Got me on this one. Between the raised runners on my AFR heads, spohn k-member, poly motor mounts, and the possibility I have the motor mount shells on the wrong side it could be anyones fault. a BFH will fix it.

The ground clearance on these is fantastic.

As for the flanges. Something is not right there. I put a 1406 gasket against the flange and centered the ports and the bolt holes are a little out. The problem is if you dremel them in the direction they need to go in your bolt head will be inside the runner. The ports are quite a bit wide vs even a 1406, so I think rather than enlarging the holes I'll just cut the flanges.

I have a head setup on my bench from doing turbo manifolds. I'll just make two slices, center all the ports and tighten it up and put a quick weld on it to keep it in place.

Those of you with small port heads, you might not have an issue.

*If the flanges/bolt holes were not an issue you could have these installed and running in under an hour (with a lift).


(*Without any emissions crap in the way)

-- Joe

 

I think the routing is odd, the metal is thin. The merge on mine isn't bad but some of them are.

I may use my flowmaster merge and weld up new s pipes. These are so high in the tunnel I'm gonna try running the pipes over the trans crossmember.

They are 3" collector with a 2 1/2" reducer welded on. I will leave it at 2 1/2.

They don't come with header bolts. 1 1/4 should be right.

-- Joe

 

Ok.

So the passenger side. I cut the flange in two spots. It almost sprung into place properly. I centered the middle tubes, bolted them in, and then worked the #2 and #8 in place. Welded it and let it cool. Done.

The driver side wasn't as bad, just the #7 was out. Made a slice, welded it in the correct spot. Done.

Again, these basically fall in place from the bottom. I clearanced just the corner of the passenger floor so I have 3/4" space between the header and the floor.

I spent about an hour to fix both flanges.

Starter clearance is just fine. I'm using a 168 tooth flywheel and a TH350.

Again, these tuck really nice high into the tunnel. I wouldn't at all be concerned about using these on a lowered car. For the money, if you want 1 3/4" headers you'd be stupid to not buy these.

Oh, I used ARP 400-1110 stainless 1" header bolts (5/16" head) with washers. They seemed to work the best.


-- Joe

 

Do you have angle plug heads? #3 on mine has issues. Plug won't fit so more modifying or shorty plugs

 

I almost pooped myself on #3, cuz I noticed the tube was bent right over the plug. But I put the plug in, tightened it, and with a 90* boot I had about 7/16" clearance to the primary tube.

Straight plug heads would be an issue I think. I have angle (afr 210s).

Shorty plugs are available for taper seat (iron heads), but I've never seen any for gasket seat ?

Right now I'm trying to decide how to do my pipes and merge to the single. The pipes supplied won't work with my crossmember (TH350). I guess I'll do a close radius S bend under the crossmember.

edit: The front bolts are in for the crossmember, I had to tap the frame. I switched to a 1982 TH200 or whatever it is crossmember which mounts to the forward bolts. The aftermarket crossmember I had made it absolutely impossible to run exhaust under it. Funny thing is, the OEM crossmember lowered the transmission a bit, and as such I didn't need to bang the floor. Wish I had tried that first.

-- Joe

 

I can only get the plug in after removing header bolts and pulling it out. The boot (90deg) is tight up against the header.



MEh, indeed only tapered. Crap, torch and hammer time it is

The short crossmember is for a saginaw 4 speed. The frame is only tapped on 82 and 83 (84?) but running a M12 through all of them is always a good idea (I routinely do this because the threads are almost always damaged)

I would fabricate a new crossmember, something a lot more sturdy and something that has either notches ot openings for the pipes.

 

I have good spark plug clearance.I tested them with removed head(eq vortec).My little finger fits between header primary tube and spark plug wire boot.Plugs are ngk tr55's and wires are accel 300+ with 90 degree boots.

 

From your photo it looks like the OE crossmember could be relieved on each side to allow the pipes to tuck a little closer to the floor. You might want to weld on some small diameter tube to reinforce it where you do the reliefs.

In you correction of the flanges, did you consider just removing the connecting portion between the three flanges. The SLPs have the three flanges separated. It seems to me that separate flanges actually helps with gasket retention? It looks like these headers (Chineseum as they may be) have a pretty decent thick flange. As much as I tend to avoid Chinese parts, they do look pretty decent, especially the merge collectors. I will have to consider these if I decide to replace my SLPs down the road.

 

Yeah, but I wanted to weld them to keep them in the "correct" spot.

I have a set of SLP's where the #7 and #8 primary is bent, I need to heat them up and fix them next week so I can sell them. This is my third set of SLP's to do that.

I kinda don't wanna cut up the 1982 crossmember. It's the only one I've seen in person in 20 years haha

I'm still on the fence, I'm thinking of doing dual 2.5" straight back. I have some chambered mufflers which I think will work pretty good. Since I have zero time to get into the shop in the next few days, I can really think it over.

But yeah, the chinese headers are nice quality. I think the y-pipe and stuff can be tossed. But the headers, at least on my engine, fit like a charm with minimal work. I spent less time "fixing" them than most members spend jacking up engine, unbolting steering, grinding k-member to make shorties fit.

-- Joe

 

[QUOTE=Twin_Turbo;5991227]I can only get the plug in after removing header bolts and pulling it out. The boot (90deg) is tight up against the header.



MEh, indeed only tapered. Crap, torch and hammer time it is

Wanna talk about poor plug clearance? Try 1 3/4" SLP shorties. It takes me about 3 hours to swap plugs using 4 different tools, including an end wrench and a plug socket that I cut the pee out of and use with visegrips to get to one plug. I have the special tool now(for plug #3 on the 4.3L S-10) that may help next time. I run AC Delco Platinum but two other brands and types of plugs made no difference. My heads are twisted wedge G2s, which have a special plug angle. I suppose that doesn't help.

 

I have a design laid out for this spring(when I have the car back out of its winter hibernation) for running dual pipes over the axle in the stock location. I'm going to look closely at running dual 3" back to Classic Chambered mufflers, as long as I can still get track bar angle right. If not, I know I can fit dual 2.5". At this point, my design centers around the shorty SLPs. I suppose it could be made to work with the long tubes as well, with a little work. I'll take a look at my SLPs before I start the work. I haven't noticed any issues with them, other than crummy plug clearance.

 

Here is mine.

-- Joe

 

Any of you guys running these with a T56 AND spohn tranny cross member?

 

The y pipe is made to run under a stock crossmember, will probably fit most anything with kickups. Don't see how a T56 would cause issues IF!!! if does not use the T5 type hydraulics (bell/conversion plate or conversion bell w/ external slave), it will fit beautifully on a hydro throwout setup. LT1 setup might work, since the slave sticks out to the back. Might need to tweak the y pipe a bit. On a T5 type setup you have to redo half the damned header. Ask me how I know

 

Im more so concerned about the tranny cross member. It hangs low, and its reinforced really well. Ill snap a picture next time im under it. Makes me wonder if i can bend the y pipe up over it, but i doubt it.

 

Maybe with an T56. Not with an auto. tried. Pan is too wide.


Twin_Turbo: Why not cut the ear off for the slave and run a Hyd TOB ?

-- Joe

 

Yes that's an option but sourcing ine for a retrofit tr3550 can be problematic. Especially being overseas.

 

anesthes, *edit* I should have read first. Doh. What did the red tranny cross member look like in your post (#4 in post 215) Im thinking its similar to what i have. Also how does it connect to the cat back? Do you cut the intermediate pipe?

 

The red crossmember was a BMR, and it looks just like a spohn. It hangs down way too low to run exhaust under it, but the rear of the trans is too wide to run 2 1/2" pipes over it without having a rattle somewhere.

The factory crossmember needs to be ground on. I've got some 3/16" and some square stock in the shop, so I'll just make a new crossmember. A 'double hump' if you will.


As far as merging it back in. I'm on the fence. I have a 900+ hp capable motor. I don't know if 3" catback is going to cut it. I might temporarily merge it into my 3" hooker catback for now, but I'm probably either going to do a 4" single or a dual 2.5" chambered.


-- Joe

 

Intresting. Hopefully ill get my Megasquirt back from warranty and ill be able to see what i can do with the spohn cross member. I wonder if i notch a V in it i can squeeze the pipes in. Im more so currious the area where it merges into the cat back. I have a 3" flowmaster setup back there currently.

 

Chamberedcexhausts tend to be restrictive. No way 2x2.5 flows like 1x4

 

I thought the chambered pipes were pretty good? I don't mean glass packs, I mean this style:

http://www.summitracing.com/parts/stw-cr2525/overview/

I have two of them. I guess I could put 'em on the stingray.

-- Joe

 

The restrictive chambered mufflers are those like Flowmaster that use deltas and flow path disruption to reduce sound. The chambered tubes in your link are a straight through design that use chambers routed around the flow path to capture sound waves. The only flow path disruption in these units is the louvers which barely protrude into the ID of the unit. These are much less restrictive.

Classic Chambered Exhaust offers the same unit in mild steel for half the price of Stainless Works. I think that painted with high temp aluminum, they will last for many years. They say that for more than 400hp, use the 3" units. They also offer them in various lengths up to 30" with a body length of 26" which I think will fit in the stock location, the longer the the unit the more sound attentuation. I suspect
Classic Chambered has sound clips on their website. I think they sound pretty nice. I plan to use their long 3" units in my new system, provided they fit.

Here's a link:

www.classicchambered.com/classic/products.html

 

Interesting. I have these in the shop, 2.5".. If they are good for around 400hp I'll just use them in the vette since that's about where that motor is, and just do a 4" single on the firebird.

Is there a 4" inlet, dual 2.5" outlet muffler that doesn't break the bank?

Or can I run a single 4" chambered pipe, and then just split the pipe to dual exits in the rear?


-- Joe

 

I'd like for companies to make more double hump crossmembers for us Third genners with T350, 700R4, T400, or T5. Seems only for the T56. Which, is great but not all of us have a T56.

 

Who makes a double hump T56 crossmember?

-- Joe

 

You have a welder a grinder and an angle finder? In that case...YOU

 

Im curious to see how many miles some people have on these headers and what the average lifespan of the header gaskets is with the gasket being so close to the bolt holes. I think that will be the one thing that stops me from pulling the trigger on these

 

Thar's why I used percys gaskets. Other option is copper. As for material furability. They stain a little... don't have a failure yet (similar vopies on other cars one is a set of kleemann amg metcedes headers...also same quality chinese stuff with kleemann price tag)

 

Hawks makes one

 

LTs were farther down my list of things to do since I'm currently running Hooker shorties but after reading this, I think LTs have just moved themselves up the list!

 

I have an angle finder but didn't use it. I lowered the car onto the safties (so the hydraulics wouldn't creep), put a pole jack under the trans and removed the T10 crossmember.


Made up my parts, tack welded it in place on the car, and then took it off and fully welded it. I've got to smooth out my corners, sandblast it, and paint it, but it's not the worst crossmember in the world.

One thing though.. When I unbolted the trans mount my tailshaft moved about 7/16" over to the left. I'm wondering if the motor mount plates on the spohn k-member are not centered. I suppose I need to stick a yoke in the tranny and see if the face is parallel to the rear end?

-- Joe

 

If it really bothers you, weld the sides of each primary and kiss it with the belt sander.

The ports are way wide, no doubt. Wider than the ports on my AFR 210s. But I think they will be fine.

-- Joe

 

On the inside of the primary? Hmm intresting thought. Im running vortec's so im not exactly shure what my port sizing is to be honest with you.

 

Like 1.35x1.35

Very small.

I'd probably run 1 5/8" headers with Vortec heads.


-- Joe

 

Here's an idea of material durability. These are the kleemann headers I was talking about, clearly they are the same OBX or other brand chinese things, come from the same factory most likely.

Anyway, they stain like this under road conditions