[stent]

the stock, original exhaust system on my '99 astro cargo 2WD is still in good condition but it's now 20 years old.
i wanted to research what i can replace the whole system with in 2019.
i thought writing up a post here would be a good way to organize what i've found and it might help anyone else with the same interest.

i'll start with a rundown of the stock exhaust system components with the GM part numbers.
i made the following searches as a 1999 astro cargo in 2WD and AWD versions.

cast iron exhaust manifolds (screen grabs from GM Parts Giant website)
i made searches for 2WD & AWD and got the same results :

left (driver's side) manifold part # 12552325 (screen grab from GM Parts Store because they have a downloadable full fitment list).
note manifold fits 1996 thru 2001 astro/safari, along with other vehicles :

right (passenger side) manifold part # 12550122 with fitment list from GM Parts Store.
note manifold fits 1996 thru 2005 astro/safari, along with other vehicles :

y-pipe with integral catalytic converter (first 2 screen grabs from GM Parts Store website):

same part number 1513680 still available at GM Parts Giant (searched as 2WD & AWD, got the same result):

muffler & tailpipe assembly (first 2 screen grabs from GM Parts Store website):

same part number still available at Arnie Bauer Cad/Buick/GMC (searched as 2wd):

for roughly $1800 plus tax & shipping i can buy new GM exhaust manifolds, y-pipe with cat & the muffler/tailpipe assembly.
YIKES !!!!!

i'll upload the post here to make sure it goes in OK then i'll continue..............

 

[markmitch]

better off going with after market hi flow converter and after market fully welded turbo muffler from Summit help the V6 breath better

 

[Mmusicman]

I didn't see ANY HEADERS!! HEADERS!! HEADERS!! :shock:

 

[stent]

better off going with after market hi flow converter and after market fully welded turbo muffler from Summit help the V6 breath better

what he said !!!
toooo expensive

 

[stent]

I didn't see ANY HEADERS!! HEADERS!! HEADERS!! :shock:

sorry to disappoint you Mmusicman, that was just the first installment.
i'm in geezer training & got sleepy & went to bed before i got to the good part.
gotta go to work now - bear with me :wave:

 

[Wiley]

Hey Rip Van Winkle, you alive?

 

[stent]

hi wiley,
had a great nap.
waiting on response from JBA headers then i'll finish this up.

until then i'll post a scan of the inspiration for the name for this little thread :

.......from the 1898 sears catalog...... :wave:

 

[Astrofarian]

Ok....you get a pass. Headers/Piles, either way, it's all exhaust-related!

-M!ke-

 

[Mmusicman]

I still don't see ANY headers... :shock:

 

[chevymaher]

LOL clickbait CLICKBAIT CLICKBAIT.

 

[joeg]

EDIT: Deleted post. I thought I found some and then realized they were v8 headers even though they were listed for our vans.

Summit shows a bunch of 4.3 headers, but I'm guessing none fit our van?
https://www.summitracing.com/search/bra ... 4294948686

 

[chevymaher]

Full sized truck headers fit. They got 4.3 headers.

If you look hard enough years ago there was a thread and they actually gave the part numbers for the unicorns that fit.

 

[joeg]

Full sized truck headers fit. They got 4.3 headers.

If you look hard enough years ago there was a thread and they actually gave the part numbers for the unicorns that fit.

Is this the thread you're referring to? https://www.astrosafari.com/viewtopic.php?f=24&t=130034

I see some 1st gen astros with part numbers... will any header that fits the first gen clear everything on the 3rd gen? And does AWD have clearance issues that RWD doesn't?

 

[joeg]

I'm strongly considering headers, I already have a catback. Does anyone know for sure which headers fit a Gen3 AWD? I definitely do not want to find out they don't fit after I take off the manifold, lol.

The pacesetter and JBA headers in that thread look interesting, but I can't tell if the people who used them had an AWD van.

 

[stent]

sorry guys, been away from posting lately.
for me in denver with the emissions testing program my header choices will be limited to direct fit short headers (they bolt up to the factory y-pipe/catalytic converter assembly).
a currently available, matched, short header set for sale for a '99 astro doesn't exist from any manufacturer that i could find.
using the info from the scans i loaded at the beginning of this post, i looked for direct fit headers for vehicles that were factory equipped with the same exhaust manifolds as the astro manifolds.
i found Pacesetter & JBA header listings that cross-referenced for one side or the other.
i didn't see any Pacesetter headers in stainless steel, but JBA had listings in stainless.
i focused on the JBA stuff from there because of the hopefully increased lifespan of stainless steel.

the available, applicable JBA listings for the cross-referenced left side header would be : 1996>98, Chevrolet/GMC, C1500/K1500, full size trucks.
the header set number is 1842SJS.

View attachment 1842SJS.pdf

the available, applicable JBA listings for the cross-referenced right side header would be : 1996-01, Chevrolet/GMC, S10 & S10 blazer, 4WD.

View attachment 1842S-3.pdf

JBA has discontinued production of these headers, that's why the left side number is for ceramic coated and the right side number is for bare stainless - that's all they have left.
the good news is that JBA will sell a mixed left/right header set from their available stock.
JBA only listed the S10 set in 4WD, but the GM manifold part number scans showed 2 & 4WD using the same manifolds.

i went ahead & ordered the headers with my tax return mad money, here's some pics :

will they fit ??
i don't know....... :shrug:

 

[Mmusicman]

FINALLY!!! SOME HEADERS!!!
Even if they don't fit.. they sure look nice!
The block huggers look like they'd probably fit!

 

[joeg]

wow, those are pretty.

So you need a different left header and right header, rather than 1 set for 1 vehicle? sheesh. Still curious if they fit.

I'm considering the pacesetter 70-1355, but they're not stainless steel. However, I saw them on a 95 AWD in the thread I linked above, so I think they fit. After talking to Andy's autosport, they also offer the ceramic coated version:
https://www.andysautosport.com/products ... C1355.html (ignore the pic, they have the wrong stock photo, but their support was very knowledgeable)

If it fits a 95 AWD, it'll fit a 2004, right? I'm thinking of pulling the trigger

 

[joeg]

After talking with @akforceten about his 2000 AWD with the pacesetter headers, I'm going to give the ceramic coated version a try. He has a 3" body lift, but hopefully my 2" will be enough, only 1 way to find out. He mentioned that you'll need spark plug wires with 90 degree boots and a little Y pipe modification.

FYI, Rockauto has them (Pacesetter 72C1355) for $256, which is WAY cheaper than everywhere else.
https://www.rockauto.com/en/parts/paces ... eader,5848 (plus 5% off with the coupon in vendor row)

 

[stent]

hi joeg,
for my situation (1999) the different left & right side headers i bought should theoretically bolt up to the factory y-pipe.
the bigger question is whether or not they will fit my van body/chassis, because the header designers evidently never test fitted their headers to an astro/safari.

for your situation (2004) the right side should be the same from 1996 thru 2005 (per my research they all used exhaust manifold part # 12550122), so the right side header of the set you're looking at should theoretically fit your y-pipe. it appears that the astro/safari left side exhaust manifold part # changed for 2002 thru 2005 (from old # 12550122 to new # 12570693). i haven't researched this newer number to try & figure out what is different. looking at the thread you referenced, one of the posters spoke of an S10 left side header needing to be reworked to fit the astro body & it did not fit the y-pipe.

 

[AstroWill]

It's outlet location might have changed, compare the y-pipe between the two.