DIY Dual Exhaust K5 Blazer...

[PWagon]

I'm going back and forth on my exhaust, and I want some opinions from you guys. The muffler shop wants mucho dinero to install new pipes all the way back with mufflers. I'm 90% sure I do the work myself, but I'm always a little concerned the first time I attempt to do something like this. Have you guys put dual exhaust on a K5 (do-it-yourself style) before? If so, how and where do you install hangers to suspend the pipes? Also, I want to keep the exhaust as quiet on the inside as possible. Any suggestions on a cheap and quiet muffler (will need two obviously). I also plan on doing two slight down spouts to direct the exhaust (dump it) right in front of the rear axle. Below is a picture that shows kinda what I want to do. I'd rather take the exhaust out behind each rear wheel, but I don't have the pipe bending tools or patience to do that. Any thoughts?

 

[Deuling]

I bought 4 u bends from summit and am cutting them at angle pieces to make a perfect 2.5" system with none of the kink bends you would buy or have an exhaust shop build.

What I have so far

Driver side

Pass side

 

[big dan]

I've done some exhaust work on my trucks before. Similar to what deuling did with buying some u bends and 90s and welding it all up. Plus summit sells a fairly cheap diy exhaust kit that comes with several 90s, 45s and pipe that should be pretty easy to install.

For mufflers, if you run it all the way out the back turbos will be pretty quiet and they are about the cheapest afaik, and I kind of like the way they sound.

Don't know about exhaust hangers, put towards the back where ever they can fit. Each truck and exhaust is going to be different so its hard to say. I used a crossmember under the bed on my truck but a blazer will have different crossmembers.

If you have fab skills and confidence in yourself you can do it. And if you try it and it doesen't work out you'll learn a lesson, no more exhaust work for you

 

[dhcomp]

What are they asking to do it?

In my experience, its WAY smarter to pay an exhaust shop to do that type of work. They are so setup to do it efficiently, its not worth your time.

 

[rebelgregory]

If you want it done quick - exhaust shop. If you have the time and attention span, I say go for it.

I have headers, true duals, and flowmaster super 40s all the way out the back. They are loud, but sound good IMO. I will tell you that I had them turned down in front of the axle like your picture and they reverberated like crazy off the ground and the drone in the cab was intolerable. If you turn them at 45 degree angles so they're aimed out towards the tires, it might be better. Of course it all depends on your setup. If you're fabbing your own, run 'em with turn-downs and if you don't like it, finish the job and run it out back. That's what I ended up doing, anyway.


.

 

[dremu]

W.r.t. mufflers, there's quiet and then there's quiet.

I had a pair of generic Summit turbo shorties, and while the snort I got from banging the skinny pedal was fun, the drone at highway speed (never mind the bark at idle) got old quick.

I've since replaced them with Walker Quiet-Flows, much better. Still a bit louder than a stock muffler, but not obnoxious.

YMMV.

-- A

 

[Bowtie85]

I put a dynomax header back kit on my k20. It was 200 from summit. Just pick your mufflers than slap er on. That's what I'd do IMO!

 

[badmix]

Im running duals with Catco cats and dynamax mufflers. I like the sound, its not too loud but you can tell its not stock.

If you are going to dump your tail pipes off the ground, its going to be loud.

I agree with others, have a muff shop do the work. I was going to do some exhaust work myself but after seeing some of the headaches the shop ran into, Im glad I didnt. There are some things I dont DIY, lol.

 

[sweetk30]

6-7 years with muffler under body no tail i finaly had to change muffler from rust out. i then also put tail pipe on .

O.M.G i can hear and think in the truck now. it was that much better. and 30 min drive or longer is better also as my body is not all tense and streesed out from the drone/noise.

do not end at muffler side out / tail out / somewere other than under body .

and buy the time you order builder kit and get 1hr in to the job its cheeper to take to a good local custom exaust builder guy shop.

i just priced it from y-pipe back on my buddys s-10 we supply muffler ( already has it ) and shop does 2.5" mid pipe and x2 tail pipes 2.25" all aluminized pipe out the door undder 200 bucks . and around 1hr later.

 

[dhcomp]

have a muff shop do the work.

Careful when searching the internet for a "muff shop". You may end up spending more money than you had intended....with no progress being made on the truck.

 

[Deuling]

I got my exhaust done at a local place. Only charged like $150 but it looked like ass.

Only other place in town wanted $400 and that's still using a standard bender.


I bought 4 mandral u bends for $64 shipped and am reusing my pipe. I'll spend the time to have a perfectly tucked up 2.5" mandral system...

 

[dhcomp]

I got my exhaust done at a local place. Only charged like $150 but it looked like ass.

Only other place in town wanted $400 and that's still using a standard bender.


I bought 4 mandral u bends for $64 shipped and am reusing my pipe. I'll spend the time to have a perfectly tucked up 2.5" mandral system...

I'm all for how badass mandrel bends are.....but based on the size tubing we are using, and stock ish motors.....a standard bend is more than sufficient.

 

[Deuling]

I'm all for how badass mandrel bends are.....but based on the size tubing we are using, and stock ish motors.....a standard bend is more than sufficient.

I think it changes the tone also. And as soon as I get my heads on, I have a feeling my motor will like the clean exhaust

 

[dhcomp]

I think it changes the tone also. And as soon as I get my heads on, I have a feeling my motor will like the clean exhaust

Yours may benefit. Most people's will not.

Pretty sure the huge kink in mine after the muffler isn't doing $hit to the performance.

That 180hp crate motor under my hood doesn't really breath much....

 

[Deuling]

Yours may benefit. Most people's will not.

Pretty sure the huge kink in mine after the muffler isn't doing $hit to the performance.

That 180hp crate motor under my hood doesn't really breath much....

Good point. Mines a little more mean lol.


I just also like how high I can tuck mine up this way. If you look at those pics, there's no way an exhaust bender could have made those bends, well without it looking like crap.

 

[Blue85]

There are a couple of issues with stitching a bunch of bends together. First, you now get rust every few inches instead of just at the muffler. So the system won't last as long. Secondly, the welds are not smooth on the inside, which affects flow. How that compares to the decreased diameter from the bending machine I don't know. If the bends are all expanded at one end for a slip fit, that's better, but the inside wall of the pipe still has ridges in it at each joint.

I usually figure that you just go a little oversize on base pipe diameter, let them bend it and the end result will be fine. It's rare to even find the parts for the price an exhaust shop can finish the job for. But you have to find the right shop. Some rip you off, some won't do anything other than "stock".

 

[Deuling]

I did this

 

[Highpsi]

Looks nice Deuling. It would be interesting to see some numbers on the dyno for all the scenarios presented here about mandrel bent tubes, standard tube bends and welded seams. I tend to agree that for most cases it simply doesn't matter that much unless you are itching to spend hours and hours tack welding and test fitting. Plus, then there's the issue of rust on all the seams as stated earlier.

And another big thing is that not all of us have a nice lift to walk around under the truck easily!

 

[Deuling]

Looks nice Deuling. It would be interesting to see some numbers on the dyno for all the scenarios presented here about mandrel bent tubes, standard tube bends and welded seams. I tend to agree that for most cases it simply doesn't matter that much unless you are itching to spend hours and hours tack welding and test fitting. Plus, then there's the issue of rust on all the seams as stated earlier.

And another big thing is that not all of us have a nice lift to walk around under the truck easily!

Haha good point I am spoiled lol.

It really didn't take that long and I think I'm gonna paint it all with some grill paint.

 

[AJMBLAZER]

I got my exhaust done at a local place. Only charged like $150 but it looked like ass.

Only other place in town wanted $400 and that's still using a standard bender.


I bought 4 mandral u bends for $64 shipped and am reusing my pipe. I'll spend the time to have a perfectly tucked up 2.5" mandral system...

Welcome to Michigan.

In the eight years I lived there after I got out of the Marines I found two shops that would mandrel bend. One wanted beaucoup bucks to do it and another was a small garage that mostly catered to muscle cars and restorations 3 hours from me with a wait time approaching a month.

I ended up doing most of my own work just with clamps, bands, and a sawzall.

I wanted a 2" exhaust on my big lifted '96 Tracker that I used to have up there. One shop in Traverse City wanted $500 to do it...and that was crimp bent pipe and their cheapo turbo muffler.
I ordered a mandrel bent system from Calmini and did it myself along with a high flow cat for less than $350.







Oh, as far as the K5 goes I looked at the Dynomax setup for my last K5. Heard it was pretty decent for the price.