Functional offroad exhaust mods

[winkosmosis]

Had I known how difficult it is to install the DPG skid, I would have gone with another option.

We only managed to get two holes drilled through the rails, and 2 in the crossmember. That steel is HARD. The right angle adapter broke, and I think I need a stronger drill than 4.5amp.

But I think I gouged the inside of my framerails with the drill. I'm scared that I weakened it... poor poor unibody. What sucks it there is no way to tell how bad it is because you can't see inside. The only thing I can think of is to get some frame stiffeners and have a shop weld them on-- But I bet that gets pretty damn expensive, not to mention the difficulty finding someone who can weld a thin unibody.

 

[winkosmosis]

Oh wait.. frame reinforcements can't fit with the DPG skid. What can I do??

 

[fyrfytr1717]

I wouldn't say it's a design flaw of the DPG skid, but I agree you do need some heavy duty equipment to do the drilling. I used my 1/2" DeWalt (7.8A corded) with a long drill bit on it. Had to sharpen the bit once or twice during the installation and damn near broke my right index finger off a couple of times when the bit caught and ripped the drill out of my hands. That being said, I still prefer the bolt through design of the DPG better than using self tappers.

Why the right angle adapter? Rock sliders in the way or something? I actually removed mine prior to installing the skid and bolted them back up afterwards. Didn't want to mess with the ol' right angle drill.

I hate those flex pipes. The PO of my camry put one on after the header and it split in half.

Now my car sounds REALLY bad.

I was told that those aren't meant to be permanent...

but idk

Seems to me they wouldn't make a "temporary" weld on part. :dunno:

 

[Rod Knee]

You need a 6 amp Dewalt (or equivalent) and carbide tipped bit(s)....and of course a center punch. I've had no problems with that combo installing rock rails and tcase skid. Use some wd40 to cool your bit down and be sure to change bits as needed. A worn bit will get you nowhere. Be patient.

 

[Cody90XJ]

You need a 6 amp Dewalt (or equivalent) and carbide tipped bit(s)....and of course a center punch. I've had no problems with that combo installing rock rails and tcase skid. Use some wd40 to cool your bit down and be sure to change bits as needed. A worn bit will get you nowhere. Be patient.

Good advise here. Make sure to use a sharp bit with a strong drill. Makes all the difference when drilling in a situation such as this. Also get some lubricate that is made for drilling. It's cheap when you consider how much longer it can help your drill bits last. Also helps to cut down on the cussing.

 

[winkosmosis]

I wouldn't say it's a design flaw of the DPG skid, but I agree you do need some heavy duty equipment to do the drilling. I used my 1/2" DeWalt (7.8A corded) with a long drill bit on it. Had to sharpen the bit once or twice during the installation and damn near broke my right index finger off a couple of times when the bit caught and ripped the drill out of my hands. That being said, I still prefer the bolt through design of the DPG better than using self tappers.

Why the right angle adapter? Rock sliders in the way or something? I actually removed mine prior to installing the skid and bolted them back up afterwards. Didn't want to mess with the ol' right angle drill.



Seems to me they wouldn't make a "temporary" weld on part. :dunno:

The pinch seams are in the way

 

[winkosmosis]

You need a 6 amp Dewalt (or equivalent) and carbide tipped bit(s)....and of course a center punch. I've had no problems with that combo installing rock rails and tcase skid. Use some wd40 to cool your bit down and be sure to change bits as needed. A worn bit will get you nowhere. Be patient.

I thought a Dewalt titanium bit would work well, but it was the worst. The long bit that I got was the only one I found. Home Depot had none, but Ace had a regular black "aircraft bit".

I'm going to buy a stronger drill.

Found a couple options on the Home Despot site

http://www.homedepot.com/h_d1/N-5yc...splay?langId=-1&storeId=10051&catalogId=10053

Is this not variable speed?
http://www.homedepot.com/h_d1/N-5yc...splay?langId=-1&storeId=10051&catalogId=10053

No mention of variable speed for this either
http://www.homedepot.com/h_d1/N-5yc...splay?langId=-1&storeId=10051&catalogId=10053


10amp Harbor Freight drill for $45
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=47991

 

[Cody90XJ]

I thought a Dewalt titanium bit would work well, but it was the worst. The long bit that I got was the only one I found. Home Depot had none, but Ace had a regular black "aircraft bit".

I'm going to buy a stronger drill.

Found a couple options on the Home Despot site

http://www.homedepot.com/h_d1/N-5yc...splay?langId=-1&storeId=10051&catalogId=10053

Is this not variable speed?
http://www.homedepot.com/h_d1/N-5yc...splay?langId=-1&storeId=10051&catalogId=10053

No mention of variable speed for this either
http://www.homedepot.com/h_d1/N-5yc...splay?langId=-1&storeId=10051&catalogId=10053


10amp Harbor Freight drill for $45
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=47991

I have a 5.4 amp DeWalt 3/8" that I changed the check out and it now able to handle 1/2" shank bits. It's never let me down but, I wish it had a handle like the real 1/2" drills have.

Go slow on the larger bits and use some cutting fluid. Makes a big difference.

 

[winkosmosis]

Are you supposed to use a carbide bit for metal or one of the masonry ones?

http://www.lowes.com/lowes/lkn?action=productDetail&productId=46479-353-HC2061&lpage=none

 

[Cody90XJ]

Are you supposed to use a carbide bit for metal or one of the masonry ones?

http://www.lowes.com/lowes/lkn?action=productDetail&productId=46479-353-HC2061&lpage=none

The masonary bit are just for cenemt and such things.

I've had some good luck with a set of Hitachi bits that I bought at Lowes. Good price and have lasted awhile.

 

[Rod Knee]

If you click on the "specifications" tab you see whether they are variable rate or not. Looks like that second one is variable rate.

I only buy Dewalt myself, when it comes to power tools. I can't afford the cheaper brands.

 

[Rod Knee]

test

 

[ehall]

The hitachi bits are pretty good. They all wear out fast when they start hitting metal.

 

[60anny]

How much did the new cat cost?

 

[AshyLarry]

The hitachi bits are pretty good. They all wear out fast when they start hitting metal.

Hitachi sucks for metal. Snapped off just about every one I have used on metal. Try the bosch, more expensive but a much better bit.

 

[Blaine B.]

Gad zooks...I just checked my LCA's and one of them is indeed creased below the rearward lip of the spring perch. Not enough to be a big worry, but something to monitor for sure. I don't know that I'd trim the lip over concern about weakening the perch.

Trimming the bottom of the "spring perch/shock mount" to prevent it fromt hitting the control arms doesn't seem to weaken it really. There are 2 pieces of metal sandwiched together. The top piece angles down at the rear so you can cut that off about an inch or so and end up right where the bottom piece sandwiches with the top piece.

 

[winkosmosis]

How much did the new cat cost?

The cat was about $100. Total cost was $190 installed. The cost for the flex pipe was $90. I think I overpaid a little considering they spent under an hour for the whole thing, but at least they did a good job.

 

[winkosmosis]

OK I have to say, the DPG skid looks awesome.

 

[winkosmosis]

The new cat is very close to the skid. Probably 1/4" clearance. It's bigger than I expected, but as long as it clears it's fine. I will probably stick a piece of baking sheet in there to protect the powdercoating from heat

 

[Destroyer]

I just finished up some exhaust mods very similar to the OP's. When I got my XJ the PO had installed a y-pipe just before the crossmember and had a (non-working) electric cutout on it which rattled against the crossmember which was driving me crazy. The rest of the exhaust was fully welded so everything had to be cut off. Starting new I added the flex pipe, a flange between the muffler and tailpipe as well as replaced the 90* bend just before the flex pipe. This allowed me to rotate the cat and muffler up slightly in preparation for a full belly skid. The flex pipe is joined to the pipe running over the crossmember with a butt-joint band clamp for easy removal. I also removed the "dent" from the downpipe while I had everything out. Now it is all 2.5" mandrel bent from the bottom of the downpipe back. Eventually I will make a new downpipe to match, but that is a ways off still.