L16 Exhaust System

[FiremarshalBill49]

I find myself in dire need of the down pipe collector for an early 72' Datsun L-16 in my 620.  The whole exhaust system will need to be replaced but my local muffler guy says it's gonna cost $200-$300 for him to fabricate just the down pipe collector piece.  There's gotta be that piece out there some where.  Can anyone help or suggest an alternative??

[banzai510(hainz)]

some one on here made the 2 hole flange but someone needs to make the Y pipe part.  Somebody has a link for that also for Y pipes and you couls pc it together.

 

Ted by Oympia might have  stash of these 620 Y pips also.

[datzenmike]

$200-300??? It's a truck so look at a D21 Hardbody down pipe so it clears the torsion bars. The flange to the manifold won't work, the KA one is just slightly too large and the three bolts don't match, but it could be trimmed off and an L series flange fitted and welded on.

 

Mklotz70 used to have the dual flange for the down pipes. He had them water jet cut out.
 


He gave me one years ago and last spring I modified mine and fit an S13 (KA engine) set of down pipes to it. I had to grind the 1.5" holes slightly larger diameter and use a gear clamp to pull the two pipes together to fit them in. Bolted the flange with the pipes in place and tacked it, then removed I did a final weld. Fit perfect. Last was to graft the down pipe to the exhaust under the front floor just ahead of the resonator.
 
 


Not suggesting you do this just saying it's just one of many things that can be done.

[wayno]

I find myself in dire need of the down pipe collector for an early 72' Datsun L-16 in my 620.  The whole exhaust system will need to be replaced but my local muffler guy says it's gonna cost $200-$300 for him to fabricate just the down pipe collector piece.  There's gotta be that piece out there some where.  Can anyone help or suggest an alternative??

 

Where in Washington are you?

[FiremarshalBill49]

I'm up in Oak Harbor.  I'm still fairly new to the wonderful world of the 620 and quickly learning parts are no where near as common as I had thought. I'm wondering if a complete new header like...  http://www.datsunparts.com/1899might be an option?

[datzenmike]

Expensive option. I'm not the guy to ask when it comes to a header. I did have one on my L16 521, the model before the 620. Took two days to get that prick on, the gasket leaked coolant so 3 tries to get it on and sealed, did not clear the torsion bar so had to ding it in with a hammer for clearance. The bad showed up much later. The collector to exhaust pipe came loose every couple of months and/or blew the gasket, rusty as fuck in 3 months, loud... you wouldn't think so but loud on long trips wears thin really fast. There was no provision for the manifold warmed air for cold weather. Worst of all I expected this thing to make my L16 fly down the highway and it was the same or maybe worse. By then I had thrown my manifold away so I couldn't go back, and the new-ish down pipe butchered and also gone. I'll never do that again on a stock engine.

 

$200-$300 for the down pipe? your exhaust guy is a crook. The entire system for that perhaps. Contact  http://community.ratsun.net/user/11-mklotz70/  he possibly has one of those flanges around. Hell easy enough to make one with a few tools. That's half the job right there.

[wayno]

First of all that is a Roadster header and it will not fit your engine/head, second a header living in the Puget Sound area will not last very long unless you found a good thick tube header which I suspect I have found most of them in WA and OR area as I have been looking for them for years and when I find them I buy them if reasonably priced, I have found 2 shorty 510/521 type and one thick long tube 620 type, the rest of the thin wall headers I have had/used get leaks a couple years after installing them, I fix them and get a few more years and then started over with a new one, I have been doing this for 20 years.

The last header I just removed was a thick type, it was still working 3/4 years later and I installed it used, but I just got thru putting my 521 work truck cab onto a 1986 720 frame/chassis and I used the thick tube 620 header I found, so far so good.

The gasser 520 I have has the stock L16 exhaust manifold on the L20b I have in it, it doesn't have any less power than an engine with a header, the only thing I don't like about the L16 exhaust system is how small the pipe is after the Y collector, but you have the choice to make a collector that exits into a larger pipe from the collector back, I will have a better exhaust system made when this one starts leaking as I used flex pipe, it is a very low truck and I had to put the exhaust pipe above the cross members and that is why I used flex pipe, it will be expensive to have a proper one made.

Mike, the thick tube header I just pulled off that has not leaked has a tag that says "TRI-MILL" tack welded on to it, it has a round piece of metal welded on two tubes that appears to be for the pipe that goes up to the air filter housing for warm air, it's the only one I have like it, and it wasn't that noisy till it pulled the last stud out of the head near the firewall, but that was not the header leaking because of shitty header, the stud came out.

[Stoffregen Motorsports]

 

 

$200-$300 for the down pipe? your exhaust guy is a crook. The entire system for that perhaps. Contact  http://community.ratsun.net/user/11-mklotz70/  he possibly has one of those flanges around. Hell easy enough to make one with a few tools. That's half the job right there.

I am continually amazed at how cheap some of you fuckers are.

 

Let's do the math. A typical shop rate down here in NorCal is anywhere between $75 and $125 per hour. Even with a fancy bending machine, you will have at least an hour and a half into that  downpipe. Probably more like two to three hours to make it fit right and look nice. That's assuming you have a muffler shop machine bend and MIG weld it. Then you've got tubing, a collector and flanges. If the shop is using cheap aluminized steel tubing and crappy three bolt flanges, sure, you're not going to get much into materials, but still probably $40 worth. Building it this way will give you nothing better than a stock downpipe.

 

If the shop uses 316 stainless tubing and V-band clamps and then TIG welds it together, I could see that downpipe costing $400 to $600.

 

Here's a pic of a y-pipe for an exhaust I built last fall. It was mild steel, but TIG welded and then heat coated and connected with V-band clamps and OEM style hangers, which I hand fabbed here. I had about 6 hours into that y-pipe alone.

 

[datzenmike]

$200 for a stock down pipe is retarded. Might as well buy the proper header for it.

[racerx]

Even with proper header you still need piping, muffler. Ill admit we datsun owners are cheap as he'll.

[Stoffregen Motorsports]

Normally I cringe at the thought of a brand or model of vehicle being gentrified, but in this case, if it means driving Datsuns into the hands of people who appreciate fine work, then I'm all for it.

[Str8jacket]

Normally I cringe at the thought of a brand or model of vehicle being gentrified, but in this case, if it means driving Datsuns into the hands of people who appreciate fine work, then I'm all for it.

There is an enormous difference between appreciation of fine work and willingness to pay for fine work.

[datzenmike]

I appreciate effective, ingenious home made solutions to get the job done. Likewise there must be lots of people with fat wallets that can afford to pay for work, fine or otherwise, but not because they appreciate it, simply because they can. Where ever possible do your own work and only pay for that which you haven't learned to do. It's a Datsun not a Ferrari.

[Stoffregen Motorsports]

Calling the guy a crook for wanting to get paid for his time... I get defensive about that. Guys in the automotive repair or fabrication industry are not automatically crooks because they want to get paid for their efforts.

 

$200 - $300 for a downpipe is completely inside the range of acceptable cost for what you're getting.

[racerx]

Yes, you do end up paying a lot for an exhaust but the shop owner also has bills, insurance, rent, employees, workers comp, tools, equipment.l, etc.

[FiremarshalBill49]

All these posts bring me back to the fact that finding a good used L16 down pipe collector is the most practical and inexpensive way to go.  The rest of the rusted exhaust system can be made up fairly easily by any competent muffler shop. This is an early 620 L16 engine (probably the same engine used in the 521) and the down pipe collector piece is shot.  The only thing a little unique about my engine is that it has an original dealer installed (in 1972) AC system which shouldn't effect the exhaust system, and a Weber carb (serial number 54244). So where do I go from here? I appreciate all your input.

[wayno]

I generally make what I can(the expensive stuff) and farm out the rest, I made my head pipe all the way down to even with the torsion bar on my 521 turbodiesel, then the exhaust shop made the rest to the tailgate, since turbodiesel I didn't need a muffler so it only cost me $200.00 for the whole thing.

The exhaust shop said the head pipe from the turbo to the underside of the truck was the hard part, so I took some scraps home from the shop and made it, I had to make the flange connection(modified flange) and 3 feet of pipe, if I have a straight piece of pipe that is long enough I can make anything I need, but it will not be pretty and there are certain things that are very hard for me to do like flattening/crushing a piece of pipe when it goes under a cross member so it don't hang down so low, this stuff is better left to someone that has the equipment, as it will only take them a couple minutes to do it while it may take me an hour or more to do the same thing with ugly results.

In general, classic vehicles are works in progress, and for a lot of us here they are daily drivers, if you own one you need to be able to work on them and be collecting parts for the future when you need them, if you don't have them your going to have to pay, in this case it's going to cost $200,/$300. either way you go from the head to just past the collector, as headers cost money also, maybe even more money if you pay to have the intake/exhaust removed to install the header, just spend the money and be done with it now, unless you can make your own collector.

[Stoffregen Motorsports]

Mike's original suggestion of using a D21 downpipe and modifying it as needed is probably the least expensive way to go.

 

You could also get a 2-into-1 collector of the right size and weld it directly to the flange, deleting the two downpipes. I've done this and it's super easy, but it hurts the power.

[Stoffregen Motorsports]

Also, don't use a cheap header. The amount of work it takes tokeep them from rotting and sturdy enough to not blow out manifold gaskets is substantial. After all that work to make it nice, you still won't have a good exhaust. Unless you use a full length header, but then you still need one with a thick head flange and a good coating to make it last.

[datzenmike]

Calling the guy a crook for wanting to get paid for his time... I get defensive about that. Guys in the automotive repair or fabrication industry are not automatically crooks because they want to get paid for their efforts.

 

$200 - $300 for a downpipe is completely inside the range of acceptable cost for what you're getting.

 

Any muffler shop should be able to build this and all the exhaust for $300-400. I assume the old pipe is still there and can be salvaged for the flange, if not the flange and at least the start of the two pipes which are only about 6" long before joining anyway. However you join the two pipes you'll never notice the difference on a stock L16.

 

I used the S14 down pipes because I found them in a scrap yard for $10 (truck load of never used, new thrown out muffler shop inventory) and for that, and the flange, had nothing to loose trying. They fit around basically the same transmission and steering in a car.

[Farmer]

I am continually amazed at how cheap some of you fuckers are.

 Best Reply ever!

[banzai510(hainz)]

dont be in a rush. There are still parts out there.

[FiremarshalBill49]

I hope so B)

[datzenmike]

'Datsun' and 'thrifty' are not mutually exclusive. Look up cheap in a thesaurus an the fourth synonym down is Datsun (owner).