Brand Newbie here - working on a Land Speed Project (1.5L or less diesel).

[Jetmugg]

It's good to be here.  I learned some valuable information today about 1.5L Diesel rod journals, and how to identify a 1.6 hydraulic lifter engine, among other things.

If anyone is interested, here is my build thread on landracing.com, which is the main hangout for Land Speed Racing stuff.

http://www.landracing.com/forum/index.php/topic,10625.0.html

I'm as busy as I can afford to be working on the chassis right now, but that doesn't stop my mind from constantly thinking about the drivetrain setup.

Right now, my fantasy is a water-to-air intercooled turbo setup, using a 1.5 rotating assembly in a 1.6 TD block, a 1.9 hyro head, and a custom injection pump.  Daily driveability is not a concern.  The ability to move around under it's own power will be needed, but the real need is for enough reliable power to put this thing in the record books.

I need to get the drivetrain right.  I don't want to spend thousands of dollars, only to get on the race course and come up 1 or 2 mph short of a record.

Steve.

[R.O.R-2.0]

It's good to be here.  I learned some valuable information today about 1.5L Diesel rod journals, and how to identify a 1.6 hydraulic lifter engine, among other things.

If anyone is interested, here is my build thread on landracing.com, which is the main hangout for Land Speed Racing stuff.

http://www.landracing.com/forum/index.php/topic,10625.0.html

I'm as busy as I can afford to be working on the chassis right now, but that doesn't stop my mind from constantly thinking about the drivetrain setup.

Right now, my fantasy is a water-to-air intercooled turbo setup, using a 1.5 rotating assembly in a 1.6 TD block, a 1.9 hyro head, and a custom injection pump.  Daily driveability is not a concern.  The ability to move around under it's own power will be needed, but the real need is for enough reliable power to put this thing in the record books.

I need to get the drivetrain right.  I don't want to spend thousands of dollars, only to get on the race course and come up 1 or 2 mph short of a record.

Steve.

i would just use a 1.6 head..

you will probably never get it to run with 1.5 displacement under a 1.9 head..

talk to Theman53.. he had an AMAZING port job done to his 1.6 head..

[RabbitJockey]

I think it would run I dunno if it would e an advantage or not to have such low compression. Probably is tho but he's only trying to break a 105mph record I went much faster with just increased boost and fueling. Huge improvements can be made on a 1.6 head for sure tho

[R.O.R-2.0]

I think it would run I dunno if it would e an advantage or not to have such low compression. Probably is tho but he's only trying to break a 105mph record I went much faster with just increased boost and fueling. Huge improvements can be made on a 1.6 head for sure tho

i bet i could take my jetta down there as it sits and break a 105mph average speed..

[theman53]

The way it goes is you have run it for at least 3 miles. They only measure 1 mile, but you have to do 3 IIRC. It isn't a I hit this number for a split second, I think they do the mile that they measure and take the speed of that run. 105 could be done easily for a couple seconds. I have had my 1.6 over that *closed course...cough cough* won't say how far but I was over 105 in the jetta. I wouldn't want to hold it for 3 miles though.

It will not be daily driven, so starting and drivability aren't really important. I don't know the numbers for sure, but I have seen it stated that the optimum CR for diesels is around 17:1 give or take .5. They claim below that there is fuel burn issues regaurding performance and above you have losses as the engine is fighting the compression to make power. It makes sense, BUT I don't have that as factual info, just reasoning from what I have heard.

[R.O.R-2.0]

The way it goes is you have run it for at least 3 miles. They only measure 1 mile, but you have to do 3 IIRC. It isn't a I hit this number for a split second, I think they do the mile that they measure and take the speed of that run. 105 could be done easily for a couple seconds. I have had my 1.6 over that *closed course...cough cough* won't say how far but I was over 105 in the jetta. I wouldn't want to hold it for 3 miles though.

It will not be daily driven, so starting and drivability aren't really important. I don't know the numbers for sure, but I have seen it stated that the optimum CR for diesels is around 17:1 give or take .5. They claim below that there is fuel burn issues regaurding performance and above you have losses as the engine is fighting the compression to make power. It makes sense, BUT I don't have that as factual info, just reasoning from what I have heard.

thats only for direct injected engines tho..

indirect injection takes inherently higher compression to start and run good.

thats why VW engines always start nice and run good, from the high compression.

look at all the old isuzu and nissan engines that were lower compression IDI engines.. they took glow plugs to start them after they were up to temp!!

[Jetmugg]

[/quote]

i bet i could take my jetta down there as it sits and break a 105mph average speed..
[/quote]

For cars, there is no special diesel class.  You have to run against the gas records.  If you have a turbo, then you have to run against records set by turbo or supercharged gassers.  Your Jetta with a 1.6L turbodiesel would have to run against blown gas Grand Touring cars in the F engine category (1.5-3L).  The existing record in that category is 224 mph.  The rules get a lot more complex and demanding for any class where the existing record is over 200. 

The 105 record only applies to diesel trucks with engine displacement under 1.5L.  Engine swaps are allowed, which is why I want to run a VW diesel in my Rampage.

Part of the "fun" of land speed racing is finding a class where you think you might be able to beat an existing record.

Steve.

[rabbid79]

I don't know the numbers for sure, but I have seen it stated that the optimum CR for diesels is around 17:1 give or take .5. They claim below that there is fuel burn issues regaurding performance and above you have losses as the engine is fighting the compression to make power. It makes sense, BUT I don't have that as factual info, just reasoning from what I have heard.

If my math is accurate, a 1.9 head on a 1.5 bottom end works out to about a 17.7:1 compression ratio.  If memory serves, losing the glow plug drops it about another full point.  I'll bet you could get that baby to fire with enough hot air (e.g. heat gun(s) directed into the intake manifold).

If you do end up going with such a low compression ratio, you'd want to push/pull it all the way to the starting line before starting it to keep the black smoke to a minimum.  I think there's a couple of really low compression ratio diesels on YouTube.  They smoke like hell until the boost comes on and then they're clean as a whistle.

It's too bad there isn't a diesel car class.  The reason I want to run a less than 2.0 TD in a 924 is in case the 1.9/2.0 TDI guys get on the band wagon and start to race their cars.  I don't want to be over 2.0 incase that eventualy happens, and they eventually have a less than 2 liter diesel class.  At this point if I were to do it, it would be about breaking personal records.

I think the diesel car class is coming though.  For the world's car manufacturers, diesel fuel economy is low hanging fruit, and we'll see many more of them in the US soon.

[mystery3]

Well... It should be starting in 85, BUT some were and weren't in 85 and 86. IIRC CRSMP5 has said that 87 and up were for sure hydro, but that is only with the original engine. If someone swapped it in the last 20 years it could be different. The usual way to tell is there are 2 returns on the front of the block and head if it is hydro. 1 if it is not. I have NEVER seen or heard of a hydro that didn't have 12mm head bolts, so all hydro should have 12mm head bolts. NOT all 12mm head bolts were hydro though. Kinda like the all squares are rectangles, but not all rectangles are squares deal.
Pic of said humps on head


I forgot but the FAQ is about 10 pages of FAQ's that might help, but there is a bunch of info in them. It is good bored reading if you have nothing better to do. I got the pic from this thread over there and it has pics of the blocks in it too.
http://www.vwdiesel.net/forum/index.php?topic=16688.0

Just for clarification purposes, many of the newer aftermarket mechanical heads have two humps of which only one is a drain. They appear outwardly to be hydraulic.

To all of you who think I could take my caddy down there and drive faster than 105mph the thing you must understand is that this is not a road course, not tarmac but rather a salt flat, it's like driving in firm sand. It's not easy to do and there's not much traction. I had a friend who was researching building a motorcycle/sidecar to race and came to understand a lot of the rules. It's an interesting endeavor, Good Luck! And keep us updated on the build.

[keaton]

does it have to be 1.5L?
Benz makes a 800cc inline 3 Common rail motor used in the smart car

[8v-of-fury]

does it have to be 1.5L?
Benz makes a 800cc inline 3 Common rail motor used in the smart car

Mucho pesos senor. (figured you'd know some espanol being in AZ. lol) 

[R.O.R-2.0]

17:1 compression in an IDI is going to be almost impossible to start.. i guarantee it.

[theman53]

I really don't think so, especially in warm climate. My uncle has a perkins I think in a tractor that he rebuilt and said the spec was around 16:1 and it is an IDI, starts slow but starts fine. New rings, starter, block heater if needed even when warm out, and all fresh it should be fine. Guys on here have engines that started with under 250psi compression. I am sure there is some formula to figure out compression numbers to a corrisponding compression ratio. Heck that mark the miser guy had an engine that had .100" + ring gaps and he said it still started and ran fine. 17:1 lights diesel in a TDI, it should light it in an IDI, just might smoke some for a bit.

The good thing is that if he tries it and fails we will know and I won't have any money in it, lol. But seriously if he tries it and it doesn't work he could then trade his aaz to someone that wants one and has a 1.6. Probably even make some on it as many want the aaz for the performance on a 1.6.

Bigger question is will the performance really be there in the 1.9 aaz head over the 1.6? He should probably do both to compare it.

[RabbitJockey]

Cr on a Franken engine is 19:1 and they start fine just smoke lots when cold.  Built tdis go really low on compression. I think something like 14.5-15:1 is the ideal compression ratio for gas and diesel regarding compression loss but I'm not sure there. That doesn't mean its the best starting compression ratio

[R.O.R-2.0]

Cr on a Franken engine is 19:1 and they start fine just smoke lots when cold.  Built tdis go really low on compression. I think something like 14.5-15:1 is the ideal compression ratio for gas and diesel regarding compression loss but I'm not sure there. That doesn't mean its the best starting compression ratio

direct injection and indirect injection are not even comparable..

direct injection will run efficiently with low compression..

indirect injection DOES NOT LIKE LOW COMPRESSION!!

IDI engines ALWAYS have more compression than direct injected engines..

ideal compression for a TDI IS NOT THE SAME AS AN IDI!!!

for real!