Total exhaust replacement....

[takza]

Well it's that time. Been patching on it...replaced the muffler...but looks like I'll have to find the parts and replace the whole system from the manifold back.

My converter looks to be ?? years old...with the heat shields falling off.

Downpipe has a leak (temp fix) where it is mounted after the manifold. Now have 2 other leaks at points further back.

Plan on just buying the downpipe and a generic converter with associated gaskets....and then going with 2" ID (?) stainless flexpipe into my current glasspack at the rear.

Looks like Advance AP has the best prices...maybe.

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In the process of finding and ordering parts...added comments:


* downpipe to manifold gasket @ $2. AdvanceAP

* downpipe with 1 3/8" ID (old one is same ID & OEM is also the same?)...Walker @ $32. AdvanceAP...a lot of restriction with this pipe..the old one is the same. This is a doublewalled pipe.

* generic converter @ $43...11" long with 2" ID pipes in/out. AdvanceAP...should be a freeflow converter due to pipe size...has a small heatshield only on one side...I'll try to make one...if you drive in dry grass, it's very important to have a good heatshield.

* 10' 2" ID SS flexpipe @ $43. JCWhitney

* several 2 1/8" exhaust pipe clamps....will use regular steel rather than ss steel...pipes are cracking...current clamps OK

* extra hangers.

* use current non-louvered glasspack muffler...they last a long time

Overall cost around $140...everything from header to ss flexpipe will be welded?...clamps from there on back

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When looking at the old commercially intalled exhaust...I see problems:

* not enough hangers installed (for a solid pipe) resulting in the pipes cracking.

* if the converter or other part of the system hits the ground...the solid pipe will have to flex...resulting in eventual cracking?

* pipe has cracked in 2 places at mounting points due to the load not being spread enough...or from welding stresses. 1 additional crack at back of converter due to lack of support.

* clamp in center was not installed for best ground clearance.

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My improvements:

* Add as many supports as needed.

* Use the SS flexpipe to reduce damage offroad and to allow free flow for exhaust.

* Make sure all clamps and converter are installed for best ground clearance.

* Be sure that exhaust tip won't get caught under rear bumper when it drags.

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What diameter to use:

<a href='http://www.hondalife.com/modules.php?na ... d=4&page=2' target='_blank'>http://www.hondalife.com/modules.php?na ... &page=2</a>


"60HP (at the crank) per square inch of (cross-sectional) flow area.

This 60HP/in^2 is to get you in the general vicinity. It also is based on the inside diameter of the tubing not the OD."

So looks like the Toyota people knew what they were doing by using a 1 3/8" ID downpipe. My system basically has the narrowest areas of 1 7/8" ID in and out of the converter and at the muffler...the rest is 2" ID flexpipe.

1 5/8" ID / 1 3/4" OD all the way back thru a free flowing muffler is the best size?

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Before installation:





Got the exhaust installed. No major problems...just a good bit of work.

Oiled all bolts 3-4 times in the 24 hours before starting.

Made a heatshield with about a 1/2" airgap for the generic converter (was inadequate as sold) out of light gauge steel and had it wire welded onto the converter. Also had the converter welded to the downpipe and a 2" OD pipe welded on the back.

Made sure all clamps were put on for max ground clearance....u-bolt ends to the side.

Only potential problem is the nearness of the exhaust to the gas tank where it is approaching the muffler....there is a need to have a serious bend in the exhaust pipe at this point to clear things...flexpipe will only bend so far....probably OK. I used some foam/alum and alum sticky sheet type material to insulate the plastic covering the tank on this corner.

The old converter was not really plugged at all...but not sure if it actually removed any pollutants or not.

Complete exhaust with glasspack could be done for $150-160.


Does this SS stuff last?




This section was at the back of a car & in front of a muffler (highest exhaust rust area?) for about 3 years...notice that the regular steel pipe has rusted out...the rust you see on the stainless is from the plain steel...good as new except for the clamp dents?

Need a pipe expander to get the dents out to reuse this.

[Typrus]

How has it faired the past 2.5 years?
You know, going from small to large back to small MIGHT be kind restrictive? Might help with velocities as well.... Dunno?

Good lord... 1 3/8? Well, thats 2.160 inch of cross section... So theoretically good to more or less 120HP? Fascinating.

[takza]

Still about like it was when I put it on...except for a rock dent in the cat heat shield...and my bargain glasspack MIGHT make it thru the winter...inlet tube is rusting out.

SS tubing still looks new...and the converter is still there despite the fact that it is only really supported on one end....need to do something about that.

[Typrus]

Mine has a hanger on one and, then only the pipe to support it on the other...
How's she sound?

[takza]

Sort of loud since I tried to clean the carbon out of the glasspack with a garden hose!

The problem with the ss flextube is that it won't support the rear of the cat very well...the solid pipe does.

[Mac]

i just got an OEM replacement and muffler from the parts store.

cost me about $100CDN all together and was the easiest thing in the world.

[Zach]

Replacement downpipe and muffler or ?

[Mac]

replacement cat-back.

any big auto parts store can get you an OEM replacement. But i've found a shop in town that does good work and can install a full custom exhaust for about $500 including high flow cat and muffler.

[Typrus]

BWA-HAHA... My local shop does great work as well. Oversize cat and a Magnaflow muffler with manifold-back 2"? $375 or so installed. Yar.

[Zach]

Napa told me $200 US and six weeks (ah, the joys of Alaska) or else $300+ with freight. A shop quoted me 372 today to do the center pipe and muffler. Jeeubs.

I'm waiting on a quote from another shop - but if you can still get an oem center pipe for >$100 cdn, I'll gladly compensate you for your time. PM me.

[takza]

After 40K miles and 6 years...my $150 exhaust system has fallen apart...mainly the converter pipes front and back got thin and cracked. So...I decided that likely the shell of the converter was still OK and I decided to buy a Harbor Freight flux core wire welder...add some extra pipe... and do the job myself.

This was going OK...despite my poor excuse for welding...when I found that I couldn't get one rounded header to downpipe nut off in order to get the parts out where I could weld them...so I ended up finding someone with a lift to do the final weld for $20.

SS pipe is still in AOK condition...am on the second glass pack muffler though....downpipe is still in good shape.

Probably good for another 2-3 years or so?

The HF welder works pretty well...minor assembly...thread the wire in and weld. Supposed to be an upgrade where you buy some Lincoln .035 wire and tips that are supposed to make welding easier. I also need a decent welding hood.

AdvanceAP has exhaust "tips" for $20 that have fiberglass inside them and are made from SS....had one of these on a V6...just using the tip and a converter...sweet sound.

[Petros]

seldom do the aftermarket stuff hold up as well as the factory material. I guess they use lower grade pipe with more impurities that initiate corrosion faster. My when I was about six my dad bought a duel exhaust "kit" from J.C. Whitney for the family Oldsmobile, I remember "helping" him install it (I was always fascinated when my dad worked on the family car, plumbing, etc.). I remember thinking how cool our Olds looked with two large pipes sticking out the rear, one on each side. It rusted in out in about 2 years (this was "BS" before smog equipment, so the exhaust may have been more corrosive). He later took it to a muffler place to have a custom exhaust welded up for it, it lasted until we got rid of the car when I was in high school.

If you are going keep the car a long time probably paying the extra fro the stainless is worth the expense.

[takza]

Do know that the adapters and so forth that they sell in the parts stores are made of thinner material than the pipe they use at muffler shops...it is about 50% thicker walled. Banged the converter around a bit...but the honey comb held up well and was intact when put back in....made my own shields.