I installed SPD exhaust adapter this weekend myself

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xrocket21

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Let me start off saying it was a brutal install!!! The adapters are pretty accessible, except for all the stuff you have to remove to get the downpipes out of the way!

Here she is all ready to be worked on

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Got it jacked up and on stands, and removed the front tires for extra access.

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Next, I unbolted the downpipes at the adapters, and loosened the rest of the downpipe connections.

At this point, I tried to wiggle the downpipe, back, around, up, down, etc, but I just couldnt get it out of the way sufficiently. I think it is possible to do without the next step, but I decided to fully drop the downpipes.

To do this, I had to support the tranny with a jack, and then unbolted a few heatshields, and dropped and removed the tranny crossmember.

At this point, now that the downpipe was free, and its a BITCH of a piece as both sides are welded together, I realized I only unplugged 3 of the 4 02 sensor wired, so I had to hold the pipes up one handed while I struggled with the last plug with the other hand.

After about 3 hours, I had access to the turbo adapters.

Now, I had tried to remove them before and they wouldn't budge, so this time I had torches ready. Quickly heating up the turbo housing to cherry red and the studs backed out fairly easily.

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I used new gaskets and new studs, but the nuts were fine.

The way these new adapters line right up to the hot side exit of the turbo is very nice, as there was a hard lip before. I can't see how these could not help flow out of the turbos, with their 25% increase in area and better flange alignment.

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I buttoned the truck back up and tested for leaks and found none.

Truck seems slightly louder, I couldn't comment on HP gains much, as 20 horse is tough to tell. All in all, I have about $225 in em, $120 for the adapters, $45 for studs, $30 for gaskets, and $20 for a stud puller different from the one I had.

The one I had was this one:

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Stud puller I bought:

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I ended up using the new one on 3 of 4, but the passenger side, closest to the block I used the kind I had originally due to fitment issues with the tightness to the block.

The SPD kit come with a "stud extractor" that fits the oval shaped top of the stud. This isn't really an extractor, as there's no way it would remove the studs without breaking them as tight as they are stuck, it is more just an installation took for the new ones.

I attempted this with 300 miles on the truck, hoping to reuse the studs and gaskets, as it was such low mileage, and they wouldnt move.

My second attempt was at 1200 miles and successful.

I dont believe it is very feasible to do this install without new studs and gaskets, no matter how new the truck is. I cant imagine trying to do it on a 50k mile truck.

I know the gains arent dyno proven yet, but I think it looks like a good mod to open up the exhaust, which will fit nicely with an intake to free up the cold side, in addition to a tune.
 
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NJSP117

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Nice write up...Seals the deal for me...I'm not doing this myself. There's a local shop I trust that would be able to do it pretty quick. Seems pretty straightforward with a torch, lift and the right extractor.
 

xxaarraa

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Gaining 20 hp on a NA motor is hard work and I can see doing this. But on a boosted motor, isn't it easier to just pay for a tune that nets you 20 hp easily? Or does this mod make your tunes net more HP down the line?

xrocket, I know you paid for and waiting on a tune already, so curious why all this effort for 20 hp?
 
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xrocket21

xrocket21

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Nice write up...Seals the deal for me...I'm not doing this myself. There's a local shop I trust that would be able to do it pretty quick. Seems pretty straightforward with a torch, lift and the right extractor.

I have seen a lot of back and forth on this, and at least part of my reason for writing it up was to show that this is a step beyond your average bolt on mod. Not to scare people away, but I think it is just out of reach for your average shade tree mechanic.

---------- Post added at 07:25 AM ---------- Previous post was at 07:24 AM ----------

Nice write up!


Sent from my iPhone using Tapatalk

Thanks, would have been nice to get more pictures, but it also sucks to pull your gloves off and clean up a bit right in the middle so you can grab your phone and get a shot.

---------- Post added at 07:29 AM ---------- Previous post was at 07:25 AM ----------

Gaining 20 hp on a NA motor is hard work and I can see doing this. But on a boosted motor, isn't it easier to just pay for a tune that nets you 20 hp easily? Or does this mod make your tunes net more HP down the line?

xrocket, I know you paid for and waiting on a tune already, so curious why all this effort for 20 hp?

I look at a few things in mods, one of them is horsepower per dollar. Early on in the game, it is easy to do a few things to get gains. First and foremost are letting the engine breathe better, since it is a big air pump. Freeing them out benefits twice, as you gain power by freeing up air flow, but you also let the turbo work easier with the better flow.

My setup will be the exhaust adapters, intake, and a tune. I feel the combo all together will make for a nice setup, not just in peak horsepower, but in efficiency, responsiveness, etc.

This should allow more net horsepower down the line, in addition to the tune.

I do not plan on replacing any of the exhaust, as they are true duals stock, loud enough stock, and aftermarket pipes sound awful, I think the adapters are a good and cheap way to open up the exhaust flow.
 

Fusco0520

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Any change in the exhaust sound? I have these at home also just haven't got around to getting them installed.
 

Fusco0520

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Thanks for the reply. I'm going to do them. Just need nice weather. Ohio weather sucks haha
 

mustangmatt95

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I did these on my truck last week. I didn't touch the downpipes at all. Remove downpipe nuts, slide down pipe flanges, remove studs, slide out OEM turbo adapters and slide in SPD ones.

Stud removal was a fight and torch is a necessity.

FYI I'm a GM World Class technician, so finding shortcuts is how I make my money lol
 
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