FAQ: The Exhaust Thread

Fiero.

And AA the rears are similar to the LG3 ones. Just inside at the joints is a little better on the s1.

Karma, would that front manifold from the lg3 fit on our series 1?

^^^ exactly what I was thinking!!!

If so, I really want try digging around for a set! I think the main problem with the rear is that the primaries lead straight down instead of toward the exit, and it doesn't help that the cross over exits into it as well. I'm thinking Robo is right that there is a lot of collision taking place in the rear manifolds.

Okay so the exhaust manifolds that Karma posted have similar bolt holes on the flanges as the series 1, but when i look up exhaust manifolds for the lg3 in the 2003 chevy s10 they have the holes for the bolts all in a horizontal line, instead of staggered like in karma's picture. Are there two LG3's?

Wow forget all of that. That is a chevy 4.3 also called lg3! This lg3 is a 3.8 buick! I'm stupid ha!

here is one of the front manifolds on ebay. http://www.ebay.com/itm/86-87-88-LESABRE-L-EXHAUST-MANIFOLD-6-231-3-8L-FR-/110800498024?fits=Year:1986%7CModel:LeSabre&hash=item19cc396d68&item=110800498024&pt=Motors_Car_Truck_Parts_Accessories&vxp=mtr#ht_2643wt_1219

and here is a picture of the flange. It shows that the ports are square and not circular, but perhaps this can be overcome.( cut and weld on a different flange?)
https://2img.net/h/i811.photobucket.com/albums/zz33/purplexj225/DSCF6341.jpg

Just to share a 'modified headers' story - I had headers refit to my cadillac 500" engine. The cadillac place sold the flanges, and gave the instructions - Buy any 454 chevy headers that fit your chassis. Cut the flanges off, bend the pipes to match the new flanges and weld on. I was quite surprised how easily the pipes flexed over after we cut the BBC flange off, and how easy the whole process actually was! If the ports on the S1 and S2 exhaust are close, this kind of modification will most likely work. Take a look at the manifold gaskets for both engines and see how far apart the ports are.

How did you flex the pipes without crimping them? I wonder if the two close primaries are the same distance apart on the series one as they are on the series 2? This would mean that only one primary would have to be altered.

I wondered the same thing, but the ports were close enough that they just moved. Granted this was an RWD V8 set of headers, so the pipes were long enough to have some room for flexing. But I was still surprised how easy it was.

I'll have to measure all of the distances of the primaries on both the series 1 and the series 2 manifolds. Karma you mentioned that you can get series 2 headers for 300 new.. where have you found these?

I'm pretty damn determined to do this! The front header looks pretty easily modifiable to fit onto a 95 flange. If you look in this picture you could cut out the few inches of difference from around where the slp logo is and then weld it back together so that it could fit the 95 flange. On the rear i would have to bend the primary on the far side and possibly add length after the bend so that it could fit to the flange. My friend could do the welding for me, but it is just a matter of finding some headers for cheap and getting some 95 flanges! Here is a picture of the front header http://www.3800performance.com/images/product_pics/slp_headers/front_header_closeup.jpg

and the rear
http://www.3800performance.com/images/product_pics/slp_headers/rear_header2_closeup.jpg
the primary on the top of the picture is the one that would need to be bent and probably extended to meet the flange

Moving the primaries is very doable. The only thing you need to be aware of here is that the series one has a 1" taller deck than the series 2. So to visualize this, if you bolted series 2 heads on to the series one engine, you would need a LIM thats around 1.5" wider and various angles to make the distance across. What this all adds up to, it the distance and angle between the front and read header pieces will not be an exact match to the series 2 headers. Nothing earth shattering, but something to be aware of that you might have to modify the crossover a bit too.

and maybe I rounded down the 300$ new a bit:
http://www.wbodystore.com/exhaust/144-pacesetter-3800-headers.html

If I had access to a bender ,I bet I could do it.The problem in making a series 1 header is the time needed to put into it.of course.And having the crossover pipe meet the rear header down stream where the dump tube in a 2 into one is a huge bending challenge.

Thanks for all of the info guys! I have read some things about the pace setters saying that they need to constantly be rewelded. Is any of this true? Because i would much rather pay that price for a set of headers that i need to modify, than the 700 something dollars for the slps. Also where would you guys recommend getting the flanges? Would it be smartest to buy an extra set of used series one manifolds?

and just for reference this is a picture of a series 1 rear manifold

http://i.ebayimg.com/00/s/NjAwWDgwMA==/$(KGrHqRHJE8E88eYCZ4,BPmwhlwMRg~~60_3.JPG

For price I'm more tempted to pick up a set of Speed Daddy headers from E-bay. 217 bucks, stainless, and they are SLP knockoffs. For something we don't know will work, and will require messing around, the lower price and beter steel only works in our favor.
LINK

And I'd find a set of flanges from a used set of S1 manifolds. Unless you know someone who can fire out a custom set.

DO IT!

Awesome. I'm gonna get my funds together and i'll definitely figure something out with these! I need some cool mods for my riv, so i can fit in with all you crazy speed demons! Do you guys think i'll be able to safely run a 2.6 pulley with these fabbed up headers? I really don't want to be pushing any KR with over 220,000 miles!

Also my welder friend says that stainless steel will not bend. Will i have to weld on different angles?

I sent an email to Hogan Performance asking them about a possible solution for a 3 in down pipe for my 95. I haven't received a reply yet, but i'm hoping the down pipe for the bonneville could be modified to work. I know that the catalytic converter flange would have to be removed, because 95's and 96's do not have a bolt on cat, but i'm just wondering if the other flange will actually attach to my rear exhaust manifold, and if not maybe i could get a custom flange from them to weld on.

deekster_caddy wrote:

Just to share a 'modified headers' story - I had headers refit to my cadillac 500" engine. The cadillac place sold the flanges, and gave the instructions - Buy any 454 chevy headers that fit your chassis. Cut the flanges off, bend the pipes to match the new flanges and weld on. I was quite surprised how easily the pipes flexed over after we cut the BBC flange off, and how easy the whole process actually was! I

Were these headers stainless steel? I have been told that stainless steel doesn't bend well, i don't know if that is true though.

RidzRiv wrote:

deekster_caddy wrote:

Just to share a 'modified headers' story - I had headers refit to my cadillac 500" engine. The cadillac place sold the flanges, and gave the instructions - Buy any 454 chevy headers that fit your chassis. Cut the flanges off, bend the pipes to match the new flanges and weld on. I was quite surprised how easily the pipes flexed over after we cut the BBC flange off, and how easy the whole process actually was! I

Were these headers stainless steel? I have been told that stainless steel doesn't bend well, i don't know if that is true though.

No, they weren't. And they were the cheapest headers I could find at the time, so I'm sure the steel was pretty thin. I just repainted them annually or so. I would imaging being stainless and a thicker steel would make them stiffer, but they should still move if they are long enough. I had this installed in an old suburban, so there was plenty of room to play with too.

has anyone ever done anything like this? some newer cars have adjustable exhaust, so when you are driving around town its quiet, but when you want to race you just press a button and it opens up and roars.
any knowledge on the subject would be appreciated!

You could get an electric cutout. You put in your exhaust before the muffler and when you hit the switch a valve moves and it moves the exhaust flow to an open exhaust and blocks off the pathway to the mufflers. I think they cost around 130 dollars. I know Codith has done this before in his riv.

where do you get that?

Check out summit racing their website has them

Just remember, Jake--there are people (usually wearing guns and badges and driving cars with
light bars & sirens) who tend to get all pissy about muffler cutouts. They think cutouts are illegal--
most likely because they are.
Not saying you shouldn't add one, but be careful showing it off. [/b]Very[b] loud. Tends to draw the wrong class of people (see above).
Cutouts were common in the '50s, when we could add them (mechanically accuated using a pull knob) for under $10. Tickets were cheap then too. And gas.

[spoiler]Of course we had no money.

Please forgive my ignorance, but I'm not schooled in "down pipes". From what I've read, it's the exhaust tube that precedes the cat converter.
Please tell me, is it separate from the rear header on the Riv 3800? And, is the stock pipe of congruent diameter with the rest of the system? If not, what's the recommended replacement?
Maybe there's a link to good photos here?
Thanks in advance.