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Exhaust manifolds

4X4HIGH

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Does anyone have a pic of some stock 89 Blazer exhaust manifolds and specifically where the exhaust pipe meets the manifold? I'm tired of dealing with header gasket leaks so I'm going back stock and I have a set of manifolds that I believe are for my application but want to be certain. If you happen to have the GM numbers on the manifolds better yet.
 
They take the geaphite cone thats flat on 1 side with the wedgey tin think to hold it in the manifokd .

Y-pipe has the tapperd flare to match the cone shape .

I might be able to get no. off mine . Sunday after noon.
 
They take the geaphite cone thats flat on 1 side with the wedgey tin think to hold it in the manifokd .

Y-pipe has the tapperd flare to match the cone shape .

I might be able to get no. off mine . Sunday after noon.
It's been so long since I removed the stock manifolds I know I dont have whatever goes between the manifold and the pipe, is that something the exhaust shop will have? I think I recall the exhaust studs using tension springs?
 
Any good parts store can get or have on the shelf .

Yes 3 studs per . Yes springs and flange nuts .
 
Does anyone have a pic of some stock 89 Blazer exhaust manifolds and specifically where the exhaust pipe meets the manifold? I'm tired of dealing with header gasket leaks so I'm going back stock and I have a set of manifolds that I believe are for my application but want to be certain. If you happen to have the GM numbers on the manifolds better yet.
Will you have to redo the entire exhaust system or can you salvage some of it? Reason I'm asking is that you might be able to go with some Corvette manifolds that are 2 1/4 or 2 1/2 center dumps that have ball and socket fittings where the pipe meets the manifold. I had to do a lot of searching to find a set that actually had AIR tubes and hopefully here soon I can afford to have my exhaust done. A stock 350 is okay with 2" exhaust, a 400+hp SBC 400....not so much.

Joel
norcal
 
Will you have to redo the entire exhaust system or can you salvage some of it? Reason I'm asking is that you might be able to go with some Corvette manifolds that are 2 1/4 or 2 1/2 center dumps that have ball and socket fittings where the pipe meets the manifold. I had to do a lot of searching to find a set that actually had AIR tubes and hopefully here soon I can afford to have my exhaust done. A stock 350 is okay with 2" exhaust, a 400+hp SBC 400....not so much.

Joel
norcal

First off, 89 Blazer uses a factory 3" single exhaust but is 2 1/2" out of the manifolds. I will have to have a new Y pipe made but no biggie. I ended up just buying a new set of Dorman exhaust manifolds since the ones I found in my container had been previously "repaired" and too damaged to make a correct repair.
 
engine masters just did a test on there show last friday night .. it was cheepy turbo mufflers to free flow straight threw muffler . and duel and single pipe .

it was interesting the power results on mufflers and how you merge the pipes on a single .

the best part was the curves . the effects were more in curve rate over the total changes .
 
engine masters just did a test on there show last friday night .. it was cheepy turbo mufflers to free flow straight threw muffler . and duel and single pipe .

it was interesting the power results on mufflers and how you merge the pipes on a single .

the best part was the curves . the effects were more in curve rate over the total changes .

Is there a linky ?
 
I checked youtube couldnt find it yet . Prob only on there motortrend streaming platform for now . I saw it on tv .
 
Mine is c or d, not sure what 90* signifies. Only thing about switching to a straight through is spark arrestor. I know the USFS will ticket vehicles with glass packs that are not on a paved road. I had to run a spark arrestor on my straight piped air cooled buggy

But my burb could benefit from HP/torque gain like that

20170318_160436.jpg
 
90* merged was like a lot of stock y-pipes and some exhaust shop cheepy jobs . 1 pipe hooks to the other @ 90* angle .

Then y-pipe was a builder y unit i think magnaflow that makes a real nice clean install and good flow .
 
Ah thanks @sweetk30, mine is custom has smooth turn from pass side to 3" main pipe. I would leave it alone but wih the 700r4 the front drive is further back so the y pipe and the drive shaft want occupy the same space. Am considering dual only down side I see is the fuel line on right side rail. Or maybe having the y behind the t case.
 
Ah thanks @sweetk30, mine is custom has smooth turn from pass side to 3" main pipe. I would leave it alone but wih the 700r4 the front drive is further back so the y pipe and the drive shaft want occupy the same space. Am considering dual only down side I see is the fuel line on right side rail. Or maybe having the y behind the t case.
As long as you don't live in California you'll probably be ok, you can't run true duals in California unless the vehicle came that way factory.
 
It may have, has heat shields, and factory hangers on both sides. No cats factory. I was registered in Kommiefornia. I got tired of having it tested and registered it in Mohave county AZ, no tests, and 5 years of tags cost less than 1 in Ca.
 
As long as you don't live in California you'll probably be ok, you can't run true duals in California unless the vehicle came that way factory.
Not true. I have run a 76, 77, and an 85 all converted from a Y pipe to true dual exhaust and never had a problem passing smog. I am north of Sacramento where they may not loo quite as close as LA or Frisco, but up here, they just run a sniffer in both exhaust pipes.

Joel
norcal
 
That was nice to see that graph. I just finished building my exhaust. 2.5” all the way back, x-piped and Borla pro XS straight through mufflers. Has a good throaty sound and no drone.

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That, is a nice exhaust. I've never had my exhaust out the back, always been out the sides which always seemed to get damaged. I'm going over the axle and at a short 45. I had a 76 long bed that had an H pipe and I developed small cracks over time. I was towing a lot of heavy loads and I wonder if taking off in granny low had to do with it. You could definitely feel a difference on the top end with an H pipe, that's for sure. Kudos to you, very nice looking exhaust.

Joel
norcal
 
I like that fab table...@Gentleman Jimmy. I've just been using a tri-vise...
 
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