VWDiesel.net The IDI, TDI, and mTDI source.
Engine Specific Info and Questions => IDI Engine => Topic started by: Antebios on March 08, 2005, 07:24:31 pm
-
Hey I've seen a few N/A 1.6l with gasser intakes on them. They look like it might be getting some more air or at least colder air then the stock N/A airbox and intake.
Anyone know which intake manifold is used for this?
-
Hey I've seen a few N/A 1.6l with gasser intakes on them. They look like it might be getting some more air or at least colder air then the stock N/A airbox and intake.
Anyone know which intake manifold is used for this?
do you have the old style N/A intake with the filter on the front of the intake, right above the valve cover, with the little tube coming out the front where the air goes in? I've seen people drill those intakes full of holes to get more air than the tube allows.
-
Hey I've seen a few N/A 1.6l with gasser intakes on them. They look like it might be getting some more air or at least colder air then the stock N/A airbox and intake.
Anyone know which intake manifold is used for this?
do you have the old style N/A intake with the filter on the front of the intake, right above the valve cover, with the little tube coming out the front where the air goes in? I've seen people drill those intakes full of holes to get more air than the tube allows.
Something tells me that drilling holes in the airbox would just be pissing in the wind. The thing about the gas intake is that it has shorter runners so intake velocity would be lower. So, you'd gain a little top end at the expense of low/mid-range torque. But, how much top end? I would guess not a lot. The valves are pretty small in a 1.6D.
-
I have my doubts about the "drill holes" in the airbox approach. At best you'd be sucking in hot air which doesn't help power much at all.
On my normally asthmatic 1.6D, I have cut the front of the air cleaner and installed a 3" thinwall PVC pipe. The pipe points over toward the bell housing end of the engine. I'm acutally using a gasser valve cover and I've rigged the throttle cable support to fit under the pipe and support it so that vibration/fatigue isn't as much of an issue. I have a 3" flexible duct attached to the end of the pipe, and the other end of the flexible duct is attached to a plastic flange with a 3" thinwall PVC pipe on it that's bolted to the firewall above and just to the right of the master cylinder. I've cut a hole through the front part of the "rain gutter" to match the pipe inlet. So I have a "cowl induction" setup on mine. The air at the base of the windshield is at fairly high pressure relative to under the hood. It might give a slight power advantage at highway speeds.
-
I have my doubts about the "drill holes" in the airbox approach. At best you'd be sucking in hot air which doesn't help power much at all.
On my normally asthmatic 1.6D, I have cut the front of the air cleaner and installed a 3" thinwall PVC pipe. The pipe points over toward the bell housing end of the engine. I'm acutally using a gasser valve cover and I've rigged the throttle cable support to fit under the pipe and support it so that vibration/fatigue isn't as much of an issue. I have a 3" flexible duct attached to the end of the pipe, and the other end of the flexible duct is attached to a plastic flange with a 3" thinwall PVC pipe on it that's bolted to the firewall above and just to the right of the master cylinder. I've cut a hole through the front part of the "rain gutter" to match the pipe inlet. So I have a "cowl induction" setup on mine. The air at the base of the windshield is at fairly high pressure relative to under the hood. It might give a slight power advantage at highway speeds.
That's probably better than just drilling holes. The intake on those cars is actually in a horrible place because it takes its air from right on top of the engine, which tends to be kind of hot. The idea would be to make as big a hole as you can in the air box then route the intake somewhere where there is likely to be cool air. The turbo cars take their air from the side of the engine bay through a hole and that seems to give cool enough air, though it heats up quite a bit when it goes through the turbo because it is close to the exhaust.
-
Im talking about running a gasser intake manifold on the diesel engine, i think its the rabbit gas intake that fits but im not sure. I want to use a cone filter on it, and route it behind the battery. My dad wont let me cut the airbox apart to put a bigger intake pipe on it.
So i was just wondering what intake manifold is used for that.
-
you can buy the cheap cone filters off ebay, thats what I did, but now I have to fab some sort of box for it so that the hot engine air doesnt get sucked into the intake :(. I just took the whole airbox right out
-
I'll take a look in the engine compartment of my Mk1 GTI tonight, and let you know if any ideas hit me. :D
-
Any intake manifold off a VW 4-cylinder crossflow, transversely mounted engine should bolt up to your VW diesel head and fit within your engine compartment, as long as it's not the kind that has fuel injectors mounting to the manifold. The diesel head sits in the same location as a gasser cylinder head and has the same intake ports and bolt pattern.
Volumetric efficiency comparison of a 1.5 liter diesel vs 1.6 liter gasser, euro GTI heron head model (same intake manifold as a A1 gasser short-runner application), taken from the VW 1.5D SAE paper:
(http://www.imagestation.com/picture/sraid160/p9296f9b1fc7a1dfaec33db4fe686d1e0/f4e36792.jpg)
The naturally aspirated diesel's induction system, including it's intake manifold design, plays a role in achieving the diesel's superior volumetric efficiency of 92% between 3000-4000rpm. The gasser manifold is probably tuned to allow help the motor to achieve it's volumetric efficiency peak at a higher RPM of 4500-5000RPM.
What are you and/or your dad hoping to achieve by swapping out your diesel intake manifold?
I wouldn't expect a short runner gasser manifold to give any benefit unless you plan on using very high RPMs often, and it will likely hurt power and torque at rpms below that point.
If you are looking for a cold air intake, I would recommend adding the cold air baffle and snorkel found in Rabbit automatic transmission diesel models. You could also use a TD air filter (they are thicker) for lower resistance of the air filter element, although I don't think it would noticeably benefit a naturally aspirated diesel.
If you want to really kill your torque, try swapping on a TD manifold on there. :lol: (Actually, if you were to try this, I would be really interested in hearing the results.)
-
I found the post that some other guy did. He used a 1.8l intake manifold and a short intake tube with a cone filter. I/m trying to see if i can get more air into the engine and also trying to get cold air thats not coming in off the top of the engine
Tell me what you think.
http://www.vwcaddy.com/topic.asp?TOPIC_ID=4070
-
I think it would work fine and be a lot of fun. Here's a couple of pics from the engine bay of my Mk1 GTI.
(http://home.earthlink.net/~rps1976/Images/Diesel/GTI1.jpg)
You can see the intake manifold at left with its snorkle heading off to the air cleaner at right just aft of the battery tray.
In the photo below, I am looking almost straight down. If you ran a 3" intake pipe over here you could then drop it down into the undercar air to avoid injesting the hot underhood air that the caddy photos show his engine getting.
(http://home.earthlink.net/~rps1976/Images/Diesel/GTI2.jpg)
-
Yeah thats what i wanted to do, run it down under the car where that space is.
Would a g60 intake manifold provide more air?
-
As stated in the thread you referred to, it's an A1 fuel injected gasser manifold. A G60 manifold has the same runner lengths as the A1 gasser, but larger runner diameters, so the G60 may allow more high-rpm flow. However the downside of the larger runner diameters is that peak velocity and therefore air inertia is lower, and so should be the boost to volumetric efficiency at the tuned RPM.
I don't see any evidence of scientific testing being done supporting the hypothesis that this change would actually increase performance. The guy writing about it has no baseline test, so his feeling that this helps performance is not reliable.
If you are considering doing this mod for performance reasons, I would urge you to do some testing before vs after of some sort, and report back on this thread with your results. That way, you will know if it helped and how much (or if it hurt and how much) and everyone can learn from your experiment. I would highly recommend doing back to back runs (comparing OEM baseline vs alternate manifolds) with an RPM-sensing G-tech or a chassis dyno if you can swing the cost, capable of plotting hp and torque vs RPMs. That way, you can see how the modification impacts performance along the entire RPM curve.
Also, I would strongly urge you to use an inline style air filter setup to intake air from in front of the radiator, rather than to intake air in the hot engine compartment which can tend to be hot. In my experience, inhaling hot air from the engine compartment can easily cost 4% power and torque throughout the RPM band. Which would pretty much guarantee the manifold would performance worse than a stock manifold ducted to cool air like the OEM automatic tranny naturally aspirated diesel setup would provide you. HTH... good luck.
-
check out what this guy did
http://www.virginiovejjet.50megs.com/
To me, that sounds like the best idea (makes it look a little rice, but who cares??)
-
And then there is Roger Brown's cold air setup:
(http://www.4crawler.com/Diesel/CheapTricks/Images/ColdAir.jpg)
It looks to be functionally equivalent to the factory Rabbit diesel Automatic cold air intake tubing and cold air baffle that mounts behind the passenger headlight. I priced the parts for this factory cold air setup out on impex by the way, and the pieces are all available for under $40.
-
Forty bucks!? :shock: :lol:
Looks like about $8 worth of elbows at Home Depot. ;)
-
I want to run it down where vwracer said. I've read all about how hot air effects the engine so i wanted to make a cold air intake.
So i was gonna use a gas intake manifold then pipe it down under the battery tray away from the radiator.
-
Looks like about $8 worth of elbows at Home Depot. ;)
That's exactly what it is.
Does anyone have a picture of the factory diesel automatic cold air setup? I have actually never seen under the hood of such a beast either in person or even a picture... have only read about it on ETKA ;)
-
check out what this guy did
http://www.virginiovejjet.50megs.com/
To me, that sounds like the best idea (makes it look a little rice, but who cares??)
That guy is fired. Who actually uses terrible hubcaps like that?
-
lol... vwmike, I'd rather those rims than the dainty steel rims on my car right now, but unless they were free, I would never install anything like that :P
btw, look at his first pictures page, and you'll see the weird K&N filter kit. He reduced his intake piping to what looks like... maybe a foot of piping?? That has to be worth something!!! Anyone know how to get one of those?
-
lol... vwmike, I'd rather those rims than the dainty steel rims on my car right now, but unless they were free, I would never install anything like that :P
btw, look at his first pictures page, and you'll see the weird K&N filter kit. He reduced his intake piping to what looks like... maybe a foot of piping?? That has to be worth something!!! Anyone know how to get one of those?
On gas engines you're supposed to gain something like 1hp for every 11 degrees you drop the intake temperature...I've always thought cold air intakes were more trouble than they're worth considering you're just not going to see temps much below ambient (we have actually seen temps below ambient using a cone filter under the hood).
-
Well, we typically have underhood temps up around 200 degrees F down here. Gaining 10 hp seems worth it to me... ;)
-
hmmm... After I put the cone filter under the hood, when the engine is hot, I swear I have less power than when its cold. Chances are i'm just sucking in hot air :( What I have to do is make some kind of housing for the cone filter and make sure it draws air from another location. I'm actually considering the air induction system though, seems kinda neat.
-
Mine looks a little more home made. I use a flexible duct with spiral reinforcing wire in it (the kind of ducting used for bathroom exhaust fans). But my pickup on the rain tray is in about the same location. The major difference with mine is I put the pipe in my airbox almost across the whole front, with the inlet pointing over by the end of the valve cover. That makes the bend into the airbox a lot less drastic and leaves me with only the 90 degree bend toward the rain gutter.
Maybe I'll take a pic or two of mine, but I'm embarassed by how dirty mine is under the hood.
-
Well, we typically have underhood temps up around 200 degrees F down here. Gaining 10 hp seems worth it to me... ;)
Underhood temps tend to rise when you're at a stop but as soon as you start moving they quickly drop. So, if you're going to have power losses it is most likely to happen only in the first 20 feet or so.
-
Posers.
(http://www.virginiovejjet.50megs.com/images/wheel.jpg)
Oh man, don't let the Vhortex crowd get a hold of this one! Check out the plastic simulated louvers! Adds another 10 Hp!!! Not only that, it looks like he's got low profile BFG T/A radials stretched on the factory wheels. And simulated carbon fiber on the hood? I may be an eccentric, but at least I exercise good taste in my contraptions.[/quote]
I think those are the "makes your 13's look like 15's" hub caps. The sad thing is we joked about that a couple of years ago. I said you'd go around a corner and the tire would flex and cause the hub cap to pop off. Not even 6 months went by and Shucks had them up for sale :roll:
-
lol you guys are horrible (j/k) main thing to look at on his car is the fact that he converted it to WVO + short K&N filter and I dont know if his muffler really counts. What I wanted to know is where to get one of his K&N filters... I could not find one anywhere :(
btw racer_x, doesnt that flex hose have those little crevisses in it? That really diminish the high flow rates :(
-
Don't forget, the fake cross drilled rotors :roll:
-
btw racer_x, doesnt that flex hose have those little crevisses in it? That really diminish the high flow rates :(
Where I have it stretched out close to tight, the inner part is pretty smooth, but around the bend there's some bunching up on the inner side of the stuff.
It's a 1.6 liter normally aspirated engine with a top engine speed of ~5000 RPM's, and I'm using 3" tubing from a relatively high pressure air source, so flow rate really isn't a huge issue. It would probably have more theoretical top flow capacity if I used a PVC elbow for the bend and eliminated the bunching of the sidewall of the duct, but I think it has so much excess capacity now that the improvement would only be on paper.
-
yea racer_x, thats true. Gotta love low rpm diesel engines. Not fuel hungry like those big impalas (my friend just got one, 200$ a month, but had to fill the car up after 2-3 days of driving and it was 40 bucks to fill???)
-
That is an awsome setup and the engine comparment is imaculate just looks awesome.
-
i tried a few of the things mentiones above on my 1.5 n/a.
first tried making up some 3" ducting and funelling (really) air from under the front LHS bumper up to the snorkel. worked ok, no big increases, but a few extra bugs in the filter box.....
then i decided to make my own aluminium mesh grille (the stock plastic one had an ugly hole in it infront of the radiator curtasy of the previous owner) and thus had cold air all over the place in the engine bay....
then i went all out, used the die griner with the cutting disc to cut out the snorkel fitting on the airbox and riveted in a little sheetmetal 80mm round stub. I got a bit of 80mm PVC downpipe, and two 80mm x 88 degree wide bends, and made a nice 's' shape to take the intake air fron right next to the radiator, getting fresh air from the front.
results? well, the car has a lot more pulling power at all rpm, so no complaints, and for $25 bucks it was a cheap mod
happy cutting
aydan
-
Take a look at a late model Golf or Jetta TDI. They have a long thin snorkle laying on top of the rad mount that traps air entering under the bonnet. It works very well, doesn't need any hacking on the grill, and should be very cheap to fab one up for a TD. I'll try to snap a pic of the one on my wife's Golf tonight.
-
Hey guys i got an intake off of a G60 and put it on. It didn't seem to help at all. Im thinking its actually is getting less air in at lower rpms so that isnt helping at all. White smoke is coming out of the exhaust at about the mid rpm range when i rev it so im guessing almost no air is getting in because of the long intake.
Ill take some pics of it tomorrow. Im going to take it off because its killing my gas mileage. 27 mpg. I got lots of PVC pipe because my dad is a plumber.
-
Old thread is old, but I think it is better to dig up the old rather than start a new thread rehashing the same stuff. My questions and suggestions are in relation to ram air. Granted, I can't brag that it is a genius idea to help roll big power with a n/a diesel....because let's face it...our motors are still the skinny puppies in the litter!
My deez is an 86 jetta with a 1.6 n/a. I have the ABA exhaust manifold, dual DP and 2 1/4 exhaust. It is ready and willing to exhale.
For quite some time, I have seen custom 3" PVC ducts to the existing airbox, I have seen people running gasser intakes and cone filters...I have even been asked why I haven't done the same.
My first experiment with "swiss cheesing" the airbox was a n00b move when I first got the car...matter of fact...swiss cheesing was my SECOND experiment! The first involved cutting a lid so that it was only a frame around the perimeter of the filter to hold it down haha!
Yet, after all these years...I am still fond of the idea. My intake is the newer version with the short metal runners that bolt to the plastic lower airbox. I believe this in itself is a decent flow upgrade compared to the earlier all metal housings? Anyways, My runners have been port matched, I run a K&N drop in filter and I still run my swiss airbox cover to this day, so long as weather permits. I always keep the stock airbox cover in the trunk, in case of rain or other circumstances where it might be preferred (it is much quieter as well!)
I understand why people want to bag on my "hot air intake". Yes. I know. Ultimately, it is allowing the motor to suck up the heated air from the engine bay instead of fresh air from behind the passenger side of the fender. When I first got my car, NONE of that ducting was there...so it was sucking in hot air one way or another haha. My swiss cheese airbox allows more airflow, as well as a less biased flow (in theory, at least ???). It seems to me that with the inlet being limited to the side, the #1 cylinder gets first dibs on the incoming air, while cylinder #4 gets the leftovers after the other 3 have eaten there share. It may be getting hot air, but it is still MORE air!
Mind you, I am speaking in layman's terms, because I am certainly no engineer!!!
Even though the gas intake still has a side inlet, I believe that in stock form, it would flow much better than the side inlet diesel setup in stock form, and would have less cylinder bias. However, I am now beginning to understand what has been mentioned earlier in this thread about the length and diameter of the runners and their effect on the powerband. Still, I find that the inside of the gasser plenum looks to be more strategically sculpted, while the lower part of the plastic diesel airbox looks rather...gridlike? A gas intake, to me, LOOKS like it was supposed to have air coming through the side! The diesel intake has short, narrow, straight runners. It looks like it should have air going straight into it. Which leads me to the ram air idea...
A unique feature of our engines being SIDEWAYS ;), is that the intake openings are all facing forward. My thought, is that with a strategically placed hoodscoop, air will be force fed straight down the throat of my modified N/A intake.
Downsides: Ricey, you have to be prepared for a rainy day, noise, excess drag? (guessing moreso for myself since I don't have a raintray? That's another story)
Benefits: cold air forced induction hahaha on the real though...more air, cold air, and increased static pressure (so says wikipedia...once again...not an engineer)
I never did any porting and polishing to my head before having it rebuilt, so I know that even with free flowing exhaust and intake is truly limited to my head and valvetrain, but I think it sounds like a reasonable experiment! I already sacrificed the airbox and I am willing to sacrifice a hood! Who wants to chip in for a Subaru hood scoop for the cause? ;)
related pictures:
(http://dubthis1.9l.tripod.com/sitebuildercontent/sitebuilderpictures/.pond/img_0061.jpg.w300h225.jpg)
I think the WRX scoop looks tasteful!
(http://i74.photobucket.com/albums/i248/flowmastergfunk/DSCF0159_zpsd65aa47b.jpg)
My current intake setup.
-
(http://i74.photobucket.com/albums/i248/flowmastergfunk/DSCF0159_zpsd65aa47b.jpg)
My current intake setup.
My gosh where did all your wires and hoses go?? :o Someday my engine bay will be that uncluttered, someday.
A hoodscoop would definitely be the coolest way to get cold air in.
-
It's gettin there! You should see my CIS bay!! It is seriously cleaner than this...and that is unacceptable!! This should really clean up once I get the battery in the trunk and get my real glowplug setup installed
Scoop to force the cold air in the intake, dual fans to coerce cool air through the radiator, and the raintray delete to let the hot air vent out from the back of the hood ;D
Almost too cool 8)
-
and the raintray delete to let the hot air vent out from the back of the hood ;D
The area above the rain tray is high pressure. It will probably push air in rather than allow it to blow out.
-
The area above the rain tray is high pressure. It will probably push air in rather than allow it to blow out.
There was further warning to this in my build thread, but thank you! Now I have all kinds of crap to worry about haha. I am not fully ready to scrap the idea yet, but more so, I am intrigued on what can be done to properly execute it...and correct my existing dilemma haha
-
It's gettin there! You should see my CIS bay!! It is seriously cleaner than this...and that is unacceptable!! This should really clean up once I get the battery in the trunk and get my real glowplug setup installed
Scoop to force the cold air in the intake, dual fans to coerce cool air through the radiator, and the raintray delete to let the hot air vent out from the back of the hood ;D
Almost too cool 8)
Yeah, hopefully I can clean things up relatively soon. I'm in the process of finishing up a motor rebuild, vnt and gasser manifold upgrade, intercooler install, battery relocation, and strut tower raising... so much at once :P At least I've got the bay repainted now, and the transmission is clean. I'll have to start a thread once I get it on the road again. But classes have started again as of today, so I'll be fighting the war on both fronts, lol.
Wouldn't the hot air just vent out the open bottom of the engine bay, like always? If you were really worried about the pressure pushing against the radiator fan's flow, you could seal off those hood vents above the now-deleted rain tray.
-
I do believe because the air rushes through the radiator, or front of the car.. and then the air is rushing faster under neath it it makes the engine bay a low pressure. With the rain tray gone, it is supplemented by that high pressure pushing down and in and maybe neutralizing the pressures?? Who knows.
-
I am really curious as to what happens with the air pressure now too...but it doesn't have any obvious negative effects. No wind noise or anything...at least not any wind noise that is louder than the engine haha.
I remembered the main reason I deleted the raintray though... getting the N/A diesel intake off is a MOTHER! Even with the rain tray gone!
I have some experimental ideas for the stock intake still, but I had everything all apart the other day and thought...what the heck. I had an spare, ported 92 cabby intake laying around that was going to be my candidate for a shaved manifold, so I thought I would run it for a little while. I only had to plug up a few holes on the front :)
I just bought a 16v scirocco throttle body for my rabbit project, when I realized that it was a two piece TB. I decided to use the short adapter to hook up a cone filter
(http://i74.photobucket.com/albums/i248/flowmastergfunk/DSCF0054_zpsf10b3ee6.jpg) (http://s74.photobucket.com/user/flowmastergfunk/media/DSCF0054_zpsf10b3ee6.jpg.html)
with an Injen cone filter and a little elbow that came with it, it sits right under the hood vent to suck in some cold air (dirt, bugs, water, etc :P)
(http://i74.photobucket.com/albums/i248/flowmastergfunk/DSCF0065_zps7a644070.jpg) (http://s74.photobucket.com/user/flowmastergfunk/media/DSCF0065_zps7a644070.jpg.html)
No noticeable benefits right now, other than the fact that it is MUCH easier to get on and off, and it actually is a bit quieter. I still have to do some fuel tuning because I am SHOCKED with what I am seeing now that I have an EGT gauge!!!! Yikes! :o
-
Too high of EGT?? What exhaust arr you running? Forgive me.. I read a lot of threads. Lol
-
I am running an ABA manifold/downpipe with 2" straight back :/
doing some tuning today and hopefully get it sorted out. It feels way too weak to be making so much heat! I would have never guessed!
-
Timing. Check what it is.. too retarded will be excessive EGT.
-
I am running an ABA manifold/downpipe with 2" straight back :/
doing some tuning today and hopefully get it sorted out. It feels way too weak to be making so much heat! I would have never guessed!
How did you solve EGT trouble? Did you change back to stock?
I am planing on buying such manifold because it should fit nicer than stock TD one, but if you had increased EGT's with it I 'll buy some other...
-
I am running an ABA manifold/downpipe with 2" straight back :/
doing some tuning today and hopefully get it sorted out. It feels way too weak to be making so much heat! I would have never guessed!
How did you solve EGT trouble? Did you change back to stock?
I am planing on buying such manifold because it should fit nicer than stock TD one, but if you had increased EGT's with it I 'll buy some other...
He appears to be NA...