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turbo intake manifold webbing is heatsoker or radiator?


DemonZ

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Any thoughts on cutting off the webbing in an attempt to have a cooler running turbo motor in a 240z? Or it won't make any appreciable difference?

 

Since the intake manifold sits right above all that turbo heat, I'm tempted to say the IM is making things inside engine compartment hotter.

 

 

The factory ZXT has an air blower which I'd rather not put in.

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If you do trim out the webbing then it would be wise to leave a small fin on either side of each runner to help dissipate what heat does still form on the heatshield. But overall it should keep the intake manifold itself cooler as more heat is able to vent up through the runners and out the vents. Of course whether or not the difference is worth the work involved in trimming it down is another thing ;)

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Sort of on the same subject. I have both webbed(n47) and unwebbed(n42) manifolds. I know the n47 came with the egr. What models didn't come with one?

 

And is there a way to modify one to look like it didn't come with one?

 

The N-42 intakes are the only NON webbed intakes that came without the EGR and those particular intakes came only on the ’75 and ’76 Federal cars' date=' (the NON California cars).

There was also a webbed, sloped/necked down, intake that didn’t get the EGR as well, but it is webbed, and it is the sloped plenum. A matter of personal preference there. I prefer the N-42 non webbed intake myself as I have yet to see a sloped, or necked down late model EFI intake look as nice as a well prepped N-42 Non EGR intake, again, personal preference.

I’ve modified several of these N-42 intakes, and a few of the EGR webbed versions as well, (LOTS of work there), for myself as well as some of our customers.

The Federal N-42 intake pictured below is going on our SOLO-II 240Z that I just finished painting today, note the “still wet” paint…. Modifications include removal of the throttle linkage towers as the new throttle valve is cable actuated, and the injectors are the modern O-ring style, C-4 Vette injectors. This intake is not a good representation of the quality of our intakes as it is for our race car, function first, cosmetics second, (and truthfully speaking, there is LOTS more left in regards to “function” with this intake, as well as aesthetics…). Not a whole lot of attention to aesthetic detail was taken into consideration for this particular intake, but it is a good example of the NON webbed, NON EGR N-42 intake that came on the ’75-’76 Federal cars.

 

[img']http://i17.photobucket.com/albums/b81/BRAAPZ/Pearl/racecar1Medium.jpg[/img]

 

 

RacecarMedium.jpg

 

 

 

 

This picture of the intake prior to painting with the new fuel rail attached.

 

Intake1Medium.jpg

 

 

 

Here is a Non Webbed “EGR” intake that we modified for a customer recently. Lots of work went into removing the EGR in such a way that it would be difficult for the casual observer to notice that this intake was originally an EGR intake. I’d prefer to not do this again, but…. for the right amount of $$$.$$, sure it can be duplicated….

 

intMedium2.jpg

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Thanks. Mine looks alot like the one mounted on the engine (but with alot more mounting points, which you have taken off nicely). I wasn't sure if it was a non egr version because I wasn't sure what that hardline front the back was for.

 

I have the equipment/skill to modify it so it looks like a non egr version, but I was just wondering you did to give it a finished look, like acid etching or another process. I guess dressing the welds and a good sand and polish will do when everything I can actually work in the car (-15 degrees, Anchorage Alaska). I don't like to polish because I don't have a real polisher (I use a dremel, grrrr)

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Thanks. Mine looks alot like the one mounted on the engine (but with alot more mounting points, which you have taken off nicely)........... . I guess dressing the welds and a good sand and polish will do when everything I can actually work in the car (-15 degrees, Anchorage Alaska). I don't like to polish because I don't have a real polisher (I use a dremel, grrrr)

 

Did I read that right, that you would possibly be doing those mods with the intake “in” the car? I sure hope not, boy oh boy would that be a project, -15, with a DREMEL!!! DOH!!! (That would make a great form of Torture for prisoners… Hmmmm…)…

 

Here is brief run down and how I tackle cleaning up these intakes.

 

With the intake removed from the car and ALL the ancillary parts removed, I jet wash the manifold, (just take it to your local automotive machine shop and ask to have it jet washed or tanked, they’ll take care of it from there). Now for the aggressive removal tactics. Mark ALL the bosses that you won’t be using and wack them off. You can use a Saws-all, hack saw, cut off wheel, or you can just gnaw them off if you have really good dental insurance. I prefer to clamp the intake down on the table of our milling machine and use a ¾” end mill and just GO FOR IT!!! (My oldest daughter enjoys performing that machining operation for me.) Then I use the die grinder with assorted non ferrous carbide bits to “rough in” what’s left. Then I use a finer carbide bit in the die grinder to smooth out the scallops left behind from the more aggressive bits. Then I’ll use a sanding roll in the die grinder to smooth out all the grinding marks.

Now, mark all the holes that will be getting filled in, i.e not used any more.

Now, depending on whether the intake is getting polished or painted, that will determine how I tackle the holes and divots left behind. If it is getting painted, I will tap all the holes for SAE pipe plugs and thread in solid brass pipe plugs into the holes and then carve the protruding remnants of the plugs down flush. I have been known to use JB Weld as filler in the divots left behind, but I won’t 100% admit to that.

If the intake is to be polished or the customer prefers the intake to be all aluminum, I’ll make small aluminum plugs from scrap billet that fit the larger holes. Then I take manifold down to a competent welder and have him weld the plugs in their respective holes and also fill in all the remaining divots. When I get the intake back, I then get out the die grinder again, and start all over on the welds till the entire intake is somewhat smooth. Then I attack the intake with a D/A, then it gets a final cleansing and paint. If it is getting polished, I get it “roughed in” so to speak and take it to a polisher to let him/her finish the job, (I’m not a polisher). Oh, before it gets painted/polished, I will set the intake up on the mill and “surface” the throttle body mounting surface and if the head mating surface received any damage, I’ll surface that as well. The Throttle body surface ALWAYS needs resurfaced if the cold start injector boss was removed/plugged, especially if the cold start injector boss was welded shut. When filling the holes that used to house the cold start injector, whether I use the pipe plug method or have it welded, the throttle body mounting surface will distort. Welding severely distorts it. Better off to just resurface it so there is no chance of a vacuum leak.

That about covers it. Each person will have their own techniques that work best for them, so use what works best for you if you so choose to do this on your own.

 

Here is the intake pictured above just prior to paint. Note the Brass plugs and if you look close, you can make out some of the divots left behind from the old boss holes, grinding divots, etc.

 

Intake1Large.jpg

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Very nice indeed. I was thinking of using a cutting wheel mounts off and for the egr, I was think of cutting the whole part off and use our shinker/stretcher machine shape a plate that would replace the section removed and TIG weld it in. But I guess your way is the easiest, I just wanted an excuse to use the shrinker.

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Me likes smooooth. Nice work Paul. I kinda wish I'd have just bought the above N42 non-webbed, but since I had 2 turbo-intakes and was port matching, the "while I'm at it" syndrome got me. I was surprised to find so many protrusions inside the intake as well.

 

 

Funny thing is when plasm cutting the underside of the egr rail, it ignited the soot/carbon in there and shot 6 inch flames out the sides! It sounded like a blow torch. I missed a good picture op.

 

 

 

Also, I would like to put to rest the issue of whether the turbo int. man is actually larger than the others. In an old Auto-X, (Steve Webb??) it was stated that the T-intake had larger runners. I recall a thread discussing it here, but can't find it.

 

 

 

It's late, so I will get out the mic. and post my tomorrow.

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Guest bastaad525
orr you can buy a non webbed manifold!!

 

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=8033314582&rd=1&sspagename=STRK%3AMESE%3AIT&rd=1

 

2418311291.jpg

 

hehe.. sorry .. I have too many manifolds in my basement

 

 

that's what I run but mine doesn't have an EGR valve. I also have no heat shield over my turbo. I'm probably losing a little performance there... always meant to put a heat shield but never got around to it. Never had any problems from it anyways and doing three back to back runs on a dyno jet with only like 5 mins between them my power was dead consistent so it must not be heat soaking too badly.

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The purpose of the webbing is to keep as much heat away from the fuel as possible.

The purpose of the heat shield under the manifold is to keep as much heat away from the manifold as possible.

 

I would not go with a non-webbed intake unless it came on the car. Meaning I wouldn't go out looking for one if I had a Non-EGR webbed manifold. I like my P82.

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The purpose of the webbing is to keep as much heat away from the fuel as possible.

The purpose of the heat shield under the manifold is to keep as much heat away from the manifold as possible.

 

Funny my 78 had both webbing and sheild. Oh well, then i don't have to hassel with making one when I switch it over.

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Me likes smooooth. Nice work Paul. I kinda wish I'd have just bought the above N42 non-webbed' date=' but since I had 2 turbo-intakes and was port matching, the "while I'm at it" syndrome got me. I was surprised to find so many protrusions inside the intake as well.

 

 

Funny thing is when plasm cutting the underside of the egr rail, it ignited the soot/carbon in there and shot 6 inch flames out the sides! It sounded like a blow torch. I missed a good picture op.

 

 

 

Also, I would like to put to rest the issue of whether the turbo int. man is actually larger than the others. In an old Auto-X, (Steve Webb??) it was stated that the T-intake had larger runners. I recall a thread discussing it here, but can't find it.

 

 

 

It's late, so I will get out the mic. and post my tomorrow.[/quote']

 

 

Yes, there are quite a few protrusions on the inside. The ones closets to the throttle vale I’ll whittle down, and there is one on the N/A manifolds near the entrance to one of the runners that I knock down as well, and the bumps for the injector bosses inside the runners, but the rest of the protrusions in the plenum I don’t bother with. Air flow in the plenum is slow enough and those protrusions are somewhat round to begin with, they really don’t pose any threat to air flow into the cylinders, not too mention they are a bit hard to reach…

 

Blow torch manifold. COOL. I like it…

 

 

 

 

As for the Turbo intake having larger runners, I never thought to check that and being as I just happen to have a couple of Turbo intakes and a few non turbo intakes out in the shop, (I was planning on letting the aseptically challenged turbo intakes go for pennies), I am now reconsidering my asking price on them.

Just went out and checked and Yes, in deed, the Turbo intake manifold runners ARE larger in diameter than the N/A Runners!!! I couldn’t get a real good measurement as I was just checking, not really measuring, but approx .080” to an1/8”th larger ID!!!

 

The intake runners of all L-series EFI manifolds are on the small size, so every little bit of runner diameter we can get helps and being as the Turbo intakes have larger inside diameter Runners as cast….. hmmmm….

 

 

The “Aesthetically challenged” Turbonic Manifold…

 

Turbo1Medium.jpg

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Very nice indeed. I was thinking of using a cutting wheel mounts off and for the egr, I was think of cutting the whole part off and use our shinker/stretcher machine shape a plate that would replace the section removed and TIG weld it in. But I guess your way is the easiest, I just wanted an excuse to use the shrinker.

 

 

 

 

AK-Z,

There are a couple ways you can handle the EGR. My preference from a cosmetic approach is to, like you said, just cut off the whole protrusion that holds the EGR valve itself off the back of the plenum. Then on the bottom of the intake, I’ll tap and plug the little ports between the runners and the EGR plenum with ¼” pipe plugs, under each intake runner, being careful to only penetrate the runner with the plug, as little as possible. I have to machine off a large enough chunk of the EGR plenum that runs the length of the air plenum so I can get my tap in there, but that goes pretty quick.

In this picture you can see the little transfer ports that go between the EGR plenum on the bottom of the Intake into the runners themselves.

 

DSC_7675Medium.jpg

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Ok, this is the last set of pictures of this intake for a while, I promise. I just installed the injectors and fuel rail and was pleasantly surprised at how well the over all appearance came out that I took a few more pics and just wanted to share. Thanks for letting me bore you all to death with all these pictures…

 

IntakeMedium.jpg

 

Intake2Medium.jpg

 

Intake3Medium.jpg

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