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Engine Specific Info and Questions => IDI Engine => Topic started by: Turbinepowered on March 02, 2007, 07:41:09 am
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Does it have any? Not talking about potential for serious horsepower, but instead a more modest amount with some good reliability. I'm shooting for stock 1.6TD figures, 68hp and 98ft-lbs, going from 52hp and 58ft-lbs.
I like the idea of the smaller displacement engine for a lower baseline fuel consumption (same basic idea behind the 1.4 TSI VWs putting out), but with the ability to put out some modest power on demand so it can get out of its own way.
Obviously some upgrades would be in order, likely a turbo (And since there are no oil jets, a nice, big intercooler and an EGT gauge are mandatory) and its companion 1.6TD injection pump; I imagine a machine shop can upgrade the head bolt holes and head to accept 12mm head bolts, with an eye toward using the studs. Maybe do the same for the crank main studs, if they're different?
I already have this engine, it's dead in the Dasher I just brought home, and since lately I've been having problems with the growing collection of engines around this place... we're going to see if what I have can be made to work, first!
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coating the piston crown's should negate the need for piston oil squirters. as long as you keep the temps low enough.
those power figures should be easily attainable... since some people have literally doubled the 1.6TD's...
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According to what I've read a Giles Pump alone should get you darn close to what you want and no turbo needed.
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Couldn't you use gasser studs? I believe they are 11mm.
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According to what I've read a Giles Pump alone should get you darn close to what you want and no turbo needed.
I don't quite have $800 to drop on a single piece of it, either. :( The rest of the car needs some loving too, like door handles on all four doors, a new latch in the back, new dashboard, rear brakes (Holy crap, we had to gut the driver's side brake drum, then stick it back on so we could roll it home! :shock:) and the shocks are feeling quite squishy so I might replace them with something a little firmer.
How much would it cost to coat piston crowns? How's that sit with thermal expansion of the piston, I'd think that would lead to cracking; ditto for the prechambers, since if I do the crowns I'll probably do the chambers too to help keep heat in.
Would gasser studs hold up to 23:1 compression for very long? I thought that the 11mm studs were part of why the 1.5s blew headgaskets often?
But check this: the sunroof doesn't leak :shock:
We drove home through a fairly torrential downpour that lasted over two hundred miles, and not a single bit of dampness around the sunroof or pillars. I was rather amazed.
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well if the injection pump has never been rebuilt.. you might be looking at an expensive rebuild anyways down the line... a good thermal reflective coating shouldn't flake off.
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I'm not sure. But they would be better than the factory strech bolts.
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Raceware makes an 11mm "Diesel Guard" stud kit. I have them in my 1.5 TD project engine.
I have the K24 turbo on, preturbo thermocouple, 2.5" downpipe and exhauste.
Still trying to get an answer out of Giles about a 1.5TD pump befor I can fire it up.
There might even be a power advantage to the 1.5 as it has a shorter stroke with the same bore size as the 1.6.
I'm no too worried about piston temp. On my 1.6, I haven't had many excursions past 1300F with 25PSI booste and smoke. The big exhaust is the key i think. perhaps the piston cooling jets are just a band aid for a crappy exhaust diameter on the original TD engines.
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perhaps the piston cooling jets are just a band aid for a crappy exhaust diameter on the original TD engines.
And the lack of a factory intercooler.
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My EGT observations are with out an intercooler. Although an intercooler is important, I really think the big pipe is more important than the intercooler. The bigger the better. I remember Jake's early observations on his pipe install. The best performance he observed was with the 2.5" down pipe, and nothing else. When he added the rest of the 2.5" exhaust system, the performance went down. If you have to choose which to do first, due to money or time constraints, do the pipe first. at least 2.5, front to back. Nos-hit, I really have to try to get my EGT up to the 1300 mark on the 1.6.
An intercooler for each is on the agenda. I have an Isuzu NPR intercooler for the 1.6, but it won't clear the larger radiator. The master plan is a ceramic coated 1.9 head on the 1.6 so hopfully I can run a slightly smaller radiator and get the big intercoller in front of it. I have a new 1.9 head, just have to figure out what i'm going to run for valves, do some port clean up, and send it out for the cermic coating.
I have a ford probe intercooler for the 1.5, but its not going anywhere without the pump.
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I've used arp vw watercooled 11mm headstuds before, they work great. Just keep an eye on egts and you don't need to coat the pistons. As said upgrading the downpipe, exhaust, air intake etc, anything to increase airflow will help gain power and lower egt.
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I've used arp vw watercooled 11mm headstuds before, they work great. Just keep an eye on egts and you don't need to coat the pistons. As said upgrading the downpipe, exhaust, air intake etc, anything to increase airflow will help gain power and lower egt.
Got an ARP part # for the 11mm studs? Or better yet, a source? I like the thought of having a little machining work as possible done on this block.
She's a "seized" block right now, but the story I've heard is that it wasn't an overheat seize, wasn't a running seize, it just... wouldn't turn over after sitting out in the yard forever. So I'm guessing, right now, that the rings are "stuck" to the side of the block, and some good solvent followed by penetrating oil will break them free. Then it's just a rering and a honing, probably go ahead and have the oil and coolant passages cleaned out, and we're done with the block in the machine shop.
A big exhaust was already planned for it, whatever engine I went with, for both easy breathing and sound considerations; I've heard some really nice sounding, big exhaust small diesels. Something about how it just throbs... with a touch of turbo-whine to provide upper range counterpoint. :D
I already have a smallish intercooler out of an Audi 5k turbo model, but I might get something bigger if I feel monied as this project moves along. My target is to have this thing up and running and on the road before the 10th of May... we'll see how things work out, won't we?
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I don't have a part # but it should be pretty easy to find, and you can find arp hardware at all sorts of auto stores.
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Like, a FLAPS type auto store (Advance, NAPA, that sort of auto store) or someplace a little less utterly generic?
I'll nose around when I'm back in my home state; I'm assuming that the thread pitch and such are the same as the 1.6 head studs? I seem to recall someone listing the pitch and such in the ARP part numbers thread...
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I like the idea of the smaller displacement engine for a lower baseline fuel consumption
I'm glad you like the idea, but I don't know how accurate it is. Certainly different engines have different baseline engine efficiencies, but I'm not under the impression that with regard to diesels that engine efficiency is necessarily displacement related. Please correct me if I'm wrong, but because diesels can run infinitely lean and have no throttle, the only downside to increased displacement (given all other factors remaining the same) is that there might be more reciprocating mass or even more weight to carry around. There is not the same fuel economy detriment that is present with gas engines which require a stoichiometric mixture. Basically if a diesel is rotating faster than necessary all fuel can be cut (free-flowing air pump) and at idle the only fuel required is enough to keep it rotating. If a larger displacement diesel is driven at the same acceleration rates as a smaller displacement diesel the vehicle gets the same fuel economy. It's only when someone takes advantage of the added horsepower/torque that is present with larger displacement, that there is a fuel economy detriment. If you want to decrease your fuel consumption it's easier to either demonstrate self-control or turn down the max fuel on a larger displacement motor than it is to swap motors IMO.
Andrew
Good write up! to sum it up, a 1.6TD making 68 hp is going to use the same amount of fuel as a 1.5TD making 68hp. Correct?!
the only time I can see the larger displacement engine using more fuel, is out of its efficiency range, say way up in the RPM's. and again, acceleration is the key in fuel consumption. Some newer TDI's run 2000 rpm @ 80mph???!!! talk about efficiency :shock:
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Certainly different engines have different baseline engine efficiencies, but I'm not under the impression that with regard to diesels that engine efficiency is necessarily displacement related. Please correct me if I'm wrong, but because diesels can run infinitely lean and have no throttle, the only downside to increased displacement (given all other factors remaining the same) is that there might be more reciprocating mass or even more weight to carry around.
There is, but it's not the same as gasoline engines because of of what you mentioned, WOT equals minimal pumping losses. If you look at a map of BSFC compared to load, you'll see that as load decreases, diesel efficiency decreases, linearly. For most gasoline engines, as load decreases, efficiency decreases exponentially. So there's a much smaller fuel economy penalty for increasing the displacement of a diesel engine compared to a gasoline engine. But it is present.
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*Sits in a corner, taking notes...*
Man I love this place. :D
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lyeinyoureye, I appreciate the info. It brings up a coupla questions. I assume that when you talk about load, you are refering to the percentage of max hp/torque that an engine develops is that correct? When I think of "load" I think "a certain amount of work". If my definition of load is what you mean, then a big engine puffing up a hill at a specific speed would be under the same "load" as a little engine puffing up the same hill at the same speed. Whereas if it is referring to the percentage of power an engine is capable of producing than the big engine would be under less load.
Andrew
Usually the latter is what I hear when people are talking about "load" with respect to engines. How "loaded" an engine is usually seems to refer to what percentage of its maximum output it's generating to cope with demands placed on it.
Which, incidentally, is where I was thinking with the "smaller displacement/smaller baseline" bit, kinda. Smaller engine run closer to its maximum output more frequently, rather than a larger engine that dips into the upper ranges of its output less frequently, and therefore is rarely as "loaded" as the smaller engine.
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Regarding larger and smaller diesel engines potentially offering the same efficiency at the same load - I offer another data point. If this were true, there would be no reason to design/build/sell small diesel engines! Since there are in fact many small diesel engines in service, lyeinyoureye's arguments must have merit. :wink:
The downside to going with a smaller engine for greater efficiency is, of course, that you have less maximum power available when you need it. So, like everything else in life, we compromise.
To me, a small engine with... a little extra booOOOOST is a good compromise. :D
-Dave
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well check this out:
(http://img395.imageshack.us/img395/2712/comparison2jl9.jpg)
I'll let this pic do all the talking... in terms of fuel economy, I would have to say that if you put a big V8 diesel in a small automobile, and found a transmission that kept rpm's near idle at highway speeds, that you would achieve as good or even better mpg than with a 1.5 running at the same speeds.
the fuel economy is lost in the upper rpm ranges.
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One other point not yet mentioned is that the larger the engine, the more frictional losses you will have, weather it be from more ring/piston contact because of larger bores, larger bearings, more cylinders & cam lobes. These add up. Larger engines will have more rotating mass, using more fuel to accelerate. You won't get a 7.3 liter engine getting 50 mpg.
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A 1.5L compared to a 1.6l is slightly more efficient, and unless the driver is constantly going near redline/peak power on the freeway, there won't be any drop in efficiency from using the smaller engine. But, the gain in efficiency isn't very large either, since we're talking about a 100cc difference in displacement. I bet having the tires 5-10psi under the sidewall spec would hit efficiency the same, if not more.
Regarding a larger V8 diesel, we could optimize it by having it idle down the freeway, but these are really small cars, so even at idle, the V8 diesel probably wouldn't be able to use enough fuel to compete with the smaller diesel unless the smaller diesel was completely wound out at the same speed. It's just too big, and given the small load required, probably wouldn't have very good efficiency. It'd still get ~30-40mpg, but I don't think it'd ever see 50mpg imo. A compromise would be an engine that's larger, but still small enough to run at high load with the right gearing. Something around 3.0L at ~1000-1500rpm at ~55mph. The TDIclub forum has some interesting posts about swapping in a taller 6th to increase mileage.
Load, in every BSFC map I've seen, is just expressed as torque, or pressure. It's the percentage of torque needed at whatever rpm. The key is rpm, since we're talking about fuel efficiency. Too high, and friction losses build up, too low and we may see other problems like oil pressure or a crappy spot in the BSFC thanks to a turbo (TDI map has this I think). Ideally, we can take map, like this on for the TDI
(http://home.earthlink.net/~rps1976/Images/Diesel/TDI%20Fuel%20Consumption%20Map.jpeg)
Or this one for a gasoline engine in one of my cars...
(http://www.v6performance.net/gallery/data/500/70SAE950805_Fig11.gif)
And find a point where the fuel consumption is smallest at some speed. But, we don't want to be upshifting every time we hit an uphill grade, so ~1/2-2/3rds of load at a proportionally lower rpm is a good rule of thumb. Granted, we may upshift more often, but the mileage increases, especially for a gasoline engine, can be huge. For instance, my engine is the dotted lines on the second map. If I can put in a custom OD gear that's half the ratio, my mileage will go from slightly over 30mpg@2000rpm@55mph, to slightly under 50mpg@1000rpm@55mph. A very nice increase. Otoh, the TDI won't see that big of an increase, but there's still something to be gained by taller gearing as well. And if we want to accelerate, we just down shift and take off... Course, most people expect "good" acceleration in all gears, and they wouldn't want to sacrifice "driveability for an extra 5-20mpg, so we don't see really tall OD gears on anything except muscle cars that are trying to avoid the gas guzzler tax (.5:1 sixth gear on a T56). And most economy cars come with CVTs, but it's still nice to know what's possible.And interesting tidbit, is that when making a car more efficient (lower Cd/Crr), we make the engine less efficient assuming the same gearing. This isn't so bad in a diesel, since engine efficiency drops linearly for the most part, but in a gasser, engine efficiency drops exponentially, so it's a definite 2 steps forward 1 step back deal.
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So what you're saying, Lye, is that really I should be looking at that transmission, rather than the engine, to go for super mileage?
So I need to go looking for a BSFC map for the 1.5 engine and do some plotting to find that 2/3rds point you were referring to... Anyone care to offer some help?
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I would agree... I can't wait to install the PD engine I'm getting. 6 speed tranny... I'm hoping that since its European, that the tranny will run around 2000 rpm @ 80mph or so. at those rpm's you can just imagine the fuel economy driving 70 mph. (i dont need to drive 80mph... especially with the new OPP stance)
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What about a 1.9 TD since you're talking about larger displacement?
Also the March issue of Performance VW magazine (its a UK mag you can get at Borders/Barnes and Noble) Has an article on swapping a newer 6 speed into a Mk 2 Golf including a list of all the parts you can source from other dubs
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Screw the tranny swap, just get 32" tall tires like I have. :wink:
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Turbinepowered, don't look into my rants to much. ;) It was more about the difference between gassers and diesel. Unless you have a gasser or your diesel is pretty large in terms of displacement I wouldn't bother with lower gearing. Generally, lower gearing is better, especially when looking at the viscosity of today's fuel compared to the fuel used back when the cars were made (more load and less rpm means the problem with timing advance/viscosity isn't as big, but you can always add oil/parrowax or adjust the pump), but for a small diesel it's not a big deal. For a gasser otoh, it can really help out with efficiency. It will help a little bit, but I don't think many would consider it worth the trade off in power available.
What you should start with is buying some tires with a low rolling resistance coefficient (Crr) and overinflate them ~10psi, or even overinflate your stock tires. Get some kind of sheeting or rubber material and cover up the underbody of the car, and check out this site (http://metrompg.com/) and this post (http://metrompg.com/posts/2006-retrospective.htm) specifically for more stuff to do. The mods he has listed increased the fuel efficiency by ~30%, but those same mods on a diesel would improve efficiency more (~40-50%?) because engine efficiency in a diesel would only decrease linearly with load. While in a gasser, he has to deal with the near exponential drop in efficiency compared to load. In the BSFC maps above, going from a third load to a sixth load decreases engine efficiency by ~40% for the gasser, so the driver may only see ~10-20% increase in fuel mileage even though they made the car itself twice as efficient. A diesel otoh, will see a relatively small drop in engine efficiency of ~15%, and can really reap the rewards of making the car twice as efficient.
Lastly, as slow as possible in top gear nets the best mileage. I'm getting the same mileage in my ~185hp V6 automatic gasser that these posters (http://vwdiesel.net/phpBB/viewtopic.php?t=7274&sid=012c1fc9171e36fa7f1a5dbac5dfebc6) are getting in their diesels because I cruise at ~55mph on the highway. As I go faster, my mileage goes down.
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what rpm's are you seeing @ 55 mph??? fuel consumption is definitely increased as the rpm's rise. at 4000 rpm you're basically getting about 15-20 mpg less than usual.
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~2000rpm. If I keep on driving the car, I'll probably into a custom fifth gear in a manual trans so I could be at ~1000rpm at ~55mph. All the OEM manuals suck balls in terms of fuel efficiency, something like 700rpm or more than the 4spd automatic. Or, I may just drop in a 3L 4 cylinder diesel... :lol:
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Question for the 1.5 netsperts:
If the 1.5 & 1.6 bore is the same, can a 1.6 TD block be used with 1.5 crank & pistons to build up a proper 1.5td?
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Question for the 1.5 netsperts:
If the 1.5 & 1.6 bore is the same, can a 1.6 TD block be used with 1.5 crank & pistons to build up a proper 1.5td?
Looks like I found my answer:
http://www.vwdieselparts.com/forum/viewtopic.php?t=6190
Anybody made this swap 1.5 internal parts into a 1.6 block??
Thanks Dean
Yes, there have been a few people who over the last couple years have put 1.5 internals in a 1.6 block and let us know about it.
I've been thinking about this setup with a turbo. It does provide better fuel economy and I've wondered if an eco turboed 1.5 could give hagar a run for his money in the search for high smileage.... and help provide a little more needed power.... it might be a good setup with the stronger 1.6 block wrapped around it.
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Now there's an idea... make a real, honest 1.5TD.
Now I have a project for the next turboblock I find. Then I'll probably do something crazy, like stick it in an old Beetle or Ghia. :lol:
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Now there's an idea... make a real, honest 1.5TD.
Now I have a project for the next turboblock I find. Then I'll probably do something crazy, like stick it in an old Beetle or Ghia. :lol:
Or Porsche 914. Mid engined, so the additional weight wouldn't ruin the handling. Plus, there are plenty of cooling setup precedents, because of the chev V8 swaps.
Ya, not that I've thought about this or anything....
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This thread has me wondering..
If I wanted the highest possible MPG while interstate cruising.. Which would be the way to go?
1.6TD Eco
1.5TD Made from a 1.6 TD Block, 1.5 Crank & Pistons, Eco IP (No LDA 8MM Plunger) Eco injectors, K14.
1.9 TDI-M Stock 10MM IP, .184 Injectors (auto TDI) K14.
1.5 - 1.6 N/A That is made to breathe well, maybe use 8MM IP
In other words... What is more efficient for constant highway load with occasional passing? i sit so small between them all that it's moot??
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Now there's an idea... make a real, honest 1.5TD.
Now I have a project for the next turboblock I find. Then I'll probably do something crazy, like stick it in an old Beetle or Ghia. :lol:
Or Porsche 914. Mid engined, so the additional weight wouldn't ruin the handling. Plus, there are plenty of cooling setup precedents, because of the chev V8 swaps.
Ya, not that I've thought about this or anything....
Yeah, but the old VWs are much, much cheaper to acquire. :D
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This thread has me wondering..
If I wanted the highest possible MPG while interstate cruising.. Which would be the way to go?
1.6TD Eco
1.5TD Made from a 1.6 TD Block, 1.5 Crank & Pistons, Eco IP (No LDA 8MM Plunger) Eco injectors, K14.
1.9 TDI-M Stock 10MM IP, .184 Injectors (auto TDI) K14.
1.5 - 1.6 N/A That is made to breathe well, maybe use 8MM IP
In other words... What is more efficient for constant highway load with occasional passing? i sit so small between them all that it's moot??
TDI-M will get better fuel economy, use a t3 turbo though.
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1.6td hydro block, 1.5 internals, 1.9 head, and a pump built to rev... it'd be an interesting setup. i wonder how it would compare to a 1.7td with a 1.9 head. someone needs to start building these frankensteins. if i had the shat i''d go for it haha.
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I´ve got 1,9 block, 1,6 crank, 1,9 NA pistons, modded 1,6 mech head and high revving 12mm pump :D
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why the 1.6 head? and did u need custom rods? haha and i know ur motor performs.
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I wanted to use 1,9 head, but got no money for it now :( So I used what I already got. And yes, custom fitted Nascar Carrillo rods 8)