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4ells
03-20-2004, 15:58
Looking to replace stock exhuast. I went to the local scotti mufler and they never heard of jk and dont carry banks--said i could order over internet and they would install. My ? is, they asked if the new kit comes off the turbo, said it would be better to spend 250 for them to bend and install pipe and go straight no converter or muffler. I wasnt planning on keeping a muffler or cat any how. advice?

whatnot
03-20-2004, 16:51
If they can bend at least 3-1/2" pipe, I would go for it. If only 3" then I would order a kit. Another thing to consider is the quality of pipe they use. I had a 3" system bent for my 93 at a local exhaust shop and it rusted fast. My kennedy kit on my 95 is still silver and has been in a lot more salt.

Wheat Whacker
03-20-2004, 19:01
I agree make sure it is good quality steel and it needs to be 3 1/2". JK's exhaust is worth the money in my book because $250 seems kinda cheap. As I spent almost $250 just replacing from the muffler back. You need to make sure the down pipe from the turbo gets replaced as it is a major POS. Forget replacing the cat and the muffler that JK sells is perfect for our units. It sounds great :D :D .

DmaxMaverick
03-20-2004, 19:46
4ells

I would suggest either purchasing a kit from JK, or others, or.....

If the shop you have been talking with has a MANDREL bender, and uses good aluminized tubing, $250 is OK. If no mandrel bender, then you'll have to go up at least 1/2" to equal the flow. If you are using aluminized tubing, it is better to clamp the joints, rather than weld them.

*note*
S/S band type clamps are 100% better than U-bolt clamps. A little more expensive, but well worth it. You can get them at NAPA or just about any medium/heavy duty truck center.

Another option would be to purchase the bends (mandrel bent elbows), and there will be almost no bending (some slight adjustments may have to be made to the straight tubing). The only thing the shop will really have to do is expand the joints where needed. I've seen lots of exhaust systems put together this way and there is no real difference between them and kits.

The only thing left is to consider a muffler. I know you said you were going to dump the muffler, but you should reconsider. It's awful rough towing (under load situations such as a 28'er) with a straight pipe. Not to mention the unwanted attention you might attract. Straight through spiral louvred types generally perform best with turbo Diesels. A muffler of 1/2" to 1" over the size of the main tubing size will be as good/better as a straight pipe. If the shop has an expander capable of handling the size of tubing you are using, it's the only way to go.

Good luck

Kennedy
03-21-2004, 07:28
How's this?

http://www.kennedydiesel.com/65exhaust.pdf

You wouldn't believe how many people think a 3" press bent system w/o a muffler is a HP system.

Reality is, 3" mandrel is marginal. 3.5 optimum, and 4" is bordering on overkill for a 6.5TD. Just my opinion...

triggerman
03-21-2004, 10:40
Summit Raceing has Flowmaster Downpipe/cross over kits and 3 1/2" universal tailpipe kits very reasonably priced. Quality is also good.

tanker
03-21-2004, 10:58
For fit, finish, and after the sale support, I'd go with John Kennedy. He has been there, and done that, when it comes to our 6.2's, 6.5's and the Duramax's. John has helped me many times on the phone, when I needed a straight correct answer. Mail order houses have good prices, but when a question comes up about how to? They don't seem to be able to help much. They usally say return it, and we'll give you credit. This is my observation over the years. smile.gif

JoeyD
03-21-2004, 13:51
On a diesel is bigger is better, true? I didn't think you could go to big on a diesel.

tanker
03-21-2004, 15:39
Joey, I have a 4" system on my burb, is it needed? Well seems tests show a 3-1/2" system is enough for a 6.5TD. At the time I did mine, John Kennedy did not have any for mine, so I have a "Jardine" downpipe, a "Stans" headers crossoverpipe, and a "BD" modified 4" system that a welder and I put together. It looks good, but it is a little big. Its better than what came on the truck from GM. :D

lupey6.5
03-21-2004, 16:48
you MUST replace the downpipe and get one without the catbox flange. i got one for about $100 then i had a shop mandrel bend me aluminized 3" all the way out but i do plan on a glasspack strait through muffler because it does have quite a presence now. you can get glasspacks w/ 4" body and 3" core if you look around. i think whitney has them if your shop can't supply.TAKE ADVANTAGE of the fact that your downpipe is out of the truck and get a pyro sensor tapped in even if you don't have the time to install the gauge right away it is worth kicking the shop a few extra bucks to drill and weld in the nut. if money is at all an issur you could probably get the size and thread pattern info from the supplier and just get the shop to weld in a nut and just put a short bolt or plug in the hole for now.

tanker
03-22-2004, 01:30
lupey6.5, I'll keep an eye out for your 94 Blazer when I'm down your way. I visit Wood-Lake often, off RT-360 in Chesterfield County. ;) What color am I lookin for? :rolleyes:

lupey6.5
03-22-2004, 09:23
its white and if i'm out that way i'm usually working so i'll be pulling a wells cargo 5x8 closed trailer, white also. i'll look for you too what color is your burb?

BUZZ
03-22-2004, 14:59
Anyone running a Flowmaster muffler with 4"in and out?
Buzz