914 Diesel build.... Options

[Porschef]

Keep on keepin' on... (IMG:style_emoticons/default/beerchug.gif) (IMG:style_emoticons/default/beerchug.gif)

[Dave_Darling]

I don't know the gearing letters, but maybe a nice tall 5th in the 901 is the way to go for now.

The stock 914 5th gear is the tallest original gear made for the 901-based gearboxes that I know of.

To go taller, you "flip" a gear set--that is, you switch which of the two shafts the gears ride on. There's one gear that goes on the main shaft, and one that goes on the pinion shaft; you move the first gear to the pinion shaft and the second gear to the main shaft.

Usually it's a 3rd gear that gets flipped.

https://members.rennlist.com/chuxter/901&915ratios.htm

--DD

[PatrickB]

I don't know the gearing letters, but maybe a nice tall 5th in the 901 is the way to go for now.

The stock 914 5th gear is the tallest original gear made for the 901-based gearboxes that I know of.

To go taller, you "flip" a gear set--that is, you switch which of the two shafts the gears ride on. There's one gear that goes on the main shaft, and one that goes on the pinion shaft; you move the first gear to the pinion shaft and the second gear to the main shaft.

Usually it's a 3rd gear that gets flipped.

https://members.rennlist.com/chuxter/901&915ratios.htm

--DD

Thanks! Good to know.

[Dr Evil]

I don't know the gearing letters, but maybe a nice tall 5th in the 901 is the way to go for now.

The stock 914 5th gear is the tallest original gear made for the 901-based gearboxes that I know of.

To go taller, you "flip" a gear set--that is, you switch which of the two shafts the gears ride on. There's one gear that goes on the main shaft, and one that goes on the pinion shaft; you move the first gear to the pinion shaft and the second gear to the main shaft.

Usually it's a 3rd gear that gets flipped.

https://members.rennlist.com/chuxter/901&915ratios.htm

--DD

Because of the base circle on the gear, you can only go so small on the driven gear in 5th. ZD is stock for 914 5th gear and is the tallest stock gear. After that, a flipped H gear set (usually a second gear) is the only other alternative. This is a conversion that has been done hundreds of times without issue. The torque of a diesel wont be an issue in 5th as you are already moving and not trying to break the inertia of being stagnant, or even slow.

[Porschef]

Ahhh, that explains it. Cool. (IMG:style_emoticons/default/beerchug.gif)

[porschetub]

I'm wondering about the gearbox... The gearing may be low for a diesel, and I'm wondering how the 901-based box will hold up to diesel torque...

--DD

Yea me too ,even the crappy early model 60 hp diesel Golf motor can eat out an 020 five speed after not that long.

[PatrickB]

I don't know the gearing letters, but maybe a nice tall 5th in the 901 is the way to go for now.

The stock 914 5th gear is the tallest original gear made for the 901-based gearboxes that I know of.

To go taller, you "flip" a gear set--that is, you switch which of the two shafts the gears ride on. There's one gear that goes on the main shaft, and one that goes on the pinion shaft; you move the first gear to the pinion shaft and the second gear to the main shaft.

Usually it's a 3rd gear that gets flipped.

https://members.rennlist.com/chuxter/901&915ratios.htm

Because of the base circle on the gear, you can only go so small on the driven gear in 5th. ZD is stock for 914 5th gear and is the tallest stock gear. After that, a flipped H gear set (usually a second gear) is the only other alternative. This is a conversion that has been done hundreds of times without issue. The torque of a diesel wont be an issue in 5th as you are already moving and not trying to break the inertia of being stagnant, or even slow.

Sounds like the solution I'll use when I get there, but I don't think it will be this summer. Can you give me a ballpark of what the revs will be at say 60 mph? That's highway cruising gear, not pound on it gear.

--DD

[PatrickB]

I'm wondering about the gearbox... The gearing may be low for a diesel, and I'm wondering how the 901-based box will hold up to diesel torque...

--DD

Yea me too ,even the crappy early model 60 hp diesel Golf motor can eat out an 020 five speed after not that long.

Been running this exact engine on an 020 for a lot of years. Put at least 350,000 kms on it. Replaced one gearbox about 15 years ago not long after I got the car. I guess it depends how you use it.... I don't baby it though. The fuel and boost was turned up a lot of years ago, I'm not shy with the throttle, and I occasionally pull a 1000 pound tent trailer with it. I don't think I'll have problems with the 901. I do run synthetic oil in the 020 though... I wonder if that helps? Made it shift smoother.

[914forme]

Can you give me a ballpark of what the revs will be at say 60 mph? That's highway cruising gear, not pound on it gear.

Yes I can, depends on your trie size as it determines you overall ratio.

Stock R&P Tires are 225/55-16

ZD 2500 RPM
HA 2200 RPM
H 2050 RPM

All approximates the graphs have not real great resolution to give the RPM down to the 1 RPM increments.

[Dr Evil]

I thought the little diesels like to rev high, though? The little 240D Mercedes I had would be screaming at fwy speeds. I actually though it was missing a gear.

[PatrickB]

I thought the little diesels like to rev high, though? The little 240D Mercedes I had would be screaming at fwy speeds. I actually though it was missing a gear.

Depends which one. engine was hooked to a VW 020 trans that had the engine turning 2641 at 100 kph (about 62 mph). This is a 1.9 Diesel mechanical fuel injection. Wasn't sold in the US. With the small turbo it's making lots of boost by 2000 rpm. Lots of torque, was always going to put together a trans with a taller final drive (3.67 instead of 3.94) with a big overdrive to drop the rpm at highway speeds but never got around to it. And the 914 weighs a lot less than the jetta... Jetta is about 2500 pounds.
I've gone with a little bigger turbo that's more efficient and expect to have to rev a little higher to get good boost, but I still think there's lots of torque for more gear. the earlier smaller engines (1.5, 1.6 with or without turbos) don't have as much torque.

[Dr Evil]

I thought the little diesels like to rev high, though? The little 240D Mercedes I had would be screaming at fwy speeds. I actually though it was missing a gear.

Depends which one. engine was hooked to a VW 020 trans that had the engine turning 2641 at 100 kph (about 62 mph). This is a 1.9 Diesel mechanical fuel injection. Wasn't sold in the US. With the small turbo it's making lots of boost by 2000 rpm. Lots of torque, was always going to put together a trans with a taller final drive (3.67 instead of 3.94) with a big overdrive to drop the rpm at highway speeds but never got around to it. And the 914 weighs a lot less than the jetta... Jetta is about 2500 pounds.
I've gone with a little bigger turbo that's more efficient and expect to have to rev a little higher to get good boost, but I still think there's lots of torque for more gear. the earlier smaller engines (1.5, 1.6 with or without turbos) don't have as much torque.

That seems like a normal aircooled range. The diesel revs high for a watercooled, and normal to low for an aircooled (IMG:style_emoticons/default/wink.gif)

[PatrickB]

I thought the little diesels like to rev high, though? The little 240D Mercedes I had would be screaming at fwy speeds. I actually though it was missing a gear.

Depends which one. engine was hooked to a VW 020 trans that had the engine turning 2641 at 100 kph (about 62 mph). This is a 1.9 Diesel mechanical fuel injection. Wasn't sold in the US. With the small turbo it's making lots of boost by 2000 rpm. Lots of torque, was always going to put together a trans with a taller final drive (3.67 instead of 3.94) with a big overdrive to drop the rpm at highway speeds but never got around to it. And the 914 weighs a lot less than the jetta... Jetta is about 2500 pounds.
I've gone with a little bigger turbo that's more efficient and expect to have to rev a little higher to get good boost, but I still think there's lots of torque for more gear. the earlier smaller engines (1.5, 1.6 with or without turbos) don't have as much torque.

That seems like a normal aircooled range. The diesel revs high for a watercooled, and normal to low for an aircooled (IMG:style_emoticons/default/wink.gif)

IF my speedo and tach are right in the 914, then it turns about 2800 at 60 mph. Not saying it's correct mind you. It's all I've got to go by.
The Jetta was originally a gas 1.8 (same block as the diesel pretty much) and was geared to turn about 2900 at 100 k when I got it. Reving too high in my opinion for the diesel. That's why I went with the trans that I already had on the Diesel when I put the car together.

[PatrickB]

double post...

[Chris914n6]

re:position...

RH has trans blocks that move the drivetrain back 1.5" and down 3/4" to fit the SBC. With my VQ30 swap I took 2 pairs, moved the drivetrain forward that 1.5" and down 1.5" so the crap on the back of the motor would clear the truck wall. Oil pan is level with the floor pan and still use the crossbar mounts.

[Porschef]

Is there a specific year group of the trannys that will bolt right up to the ALH? I'd assume 99-05 or so? A model #?

Have a friend who's in the Netherlands right now, I've informed him that I'm in search of one... (IMG:style_emoticons/default/smile.gif)

TIA

[PatrickB]

Engine is mounted, working on trying to put a rad in the engine compartment. I have one I can get in, not sure it's big enough though with the airflow it will get where it will be. Has a fan on it though.

Made a new crossmember to mount the front of the engine, bolted it to the stock location. Used a VW mount on the right side of the motor, we'll see if I need to add one on the left side after I get it running. VW mounts them at 3 points, not 4. Going to try it and see what happens. Sitting pretty nice at the moment but no torque on it. yet... Not sure if I can get away without bridging over the gearshift rod either.

[PatrickB]

Open to thoughts from those that have done other swaps...

[914forme]

What wall thickness is the crossbar?

What I don't like, is the bar is notched, and also appears to be bent in the same location. That is the weakest point of that bar. That and the side mount of the engine which would be the rear on the VW is an over hang or fulcrum for the torque to twist that mount.

Make the shifter area a hole and add a section above it and triangulate that area to make it stronger.

Do something, what I am not sure to pickup the rear (side) engine mount better. VW drops that mount right into the lower suspension crossbar. It is a huge piece of metal that takes all that movement and transfers it directly to the wheels.

On Higher HP installs you have to change the factory mount otherwise you get wheel hop as everything fights for grip and to apply the forces induced by the torque wishing to move the entire assembly.

You could also reduce this tendency by using a chain to limit the transfer of torque in the rotational axis. From the drivers side of the frame to the drives side of the engine. Oh and I mean chain, like you want Kerberos to be restrained by when you stumble up the gates he is guarding. You do not want to deal with a 3 headed dog breaking his chain and chasing you across the regions unless your the bait to get others past the gate.

This would be the one install where a cradle might be a great idea to help keep all these forces in check.

What does your side mounts look like from the bar to the chassis? Solid, or stock 914-4 mounts installed back in the 70s?

Since your using the VW mounts in your systems I would swap out to solid mounts on the outboard side. Make these ridged as hell, I mean solid. Steel on steel on steel with new grade 8 or 8.8 hardware or better. Do not skimp on this one area, and you will be happy. Skimping on this area will lead to great deals of pain and frustration.

[PatrickB]

What wall thickness is the crossbar?

What I don't like, is the bar is notched, and also appears to be bent in the same location. That is the weakest point of that bar. That and the side mount of the engine which would be the rear on the VW is an over hang or fulcrum for the torque to twist that mount.

Make the shifter area a hole and add a section above it and triangulate that area to make it stronger.

Do something, what I am not sure to pickup the rear (side) engine mount better. VW drops that mount right into the lower suspension crossbar. It is a huge piece of metal that takes all that movement and transfers it directly to the wheels.

On Higher HP installs you have to change the factory mount otherwise you get wheel hop as everything fights for grip and to apply the forces induced by the torque wishing to move the entire assembly.

You could also reduce this tendency by using a chain to limit the transfer of torque in the rotational axis. From the drivers side of the frame to the drives side of the engine. Oh and I mean chain, like you want Kerberos to be restrained by when you stumble up the gates he is guarding. You do not want to deal with a 3 headed dog breaking his chain and chasing you across the regions unless your the bait to get others past the gate.

This would be the one install where a cradle might be a great idea to help keep all these forces in check.

What does your side mounts look like from the bar to the chassis? Solid, or stock 914-4 mounts installed back in the 70s?

Since your using the VW mounts in your systems I would swap out to solid mounts on the outboard side. Make these ridged as hell, I mean solid. Steel on steel on steel with new grade 8 or 8.8 hardware or better. Do not skimp on this one area, and you will be happy. Skimping on this area will lead to great deals of pain and frustration.

Didn't want to notch the bar, but had to in order to get enough rotation on the shifter to get to all the gears. Already seriously considering a bridge over the cutout. It is boxed in already. Bar is a piece of heavy wall 1 by 2 tubing, bent a total of 2 inches out of line on the horizontal, no bend on the vertical. Bent on a press, 2 bends centred on 20 inches each with about 5/8" deflection give or take. Had to bend for clearance or cut and weld. Mounts to body are solid, which is the way the car was when I bought it with the 2 l engine. Hardware is grade 10... The mount I used is complete including the part that bolts to the crossmember in the mark 2. It bolts to 2 upright pieces, gusseted solid between them, welded to a plate that's welded to the bar. said plate is gusseted underneath to the bar too. I'm not at all concerned about this mount except that it's so far off center. I am concerned that there might be too much movement when torque is applied.
Trans mounts on the back are some form of solid Delrin with aluminum I believe, also the way I bought the car.
3rd mount on this engine in the stock location would have been at the back of the block, haven't figured out a good way to do that. Have thought about another mount on the left side at the front using the power steering mount casting, still thinking. Thought about a chain on the left already, I've seen it before on big motors in little cars. This one isn't THAT big an engine but it does make good torque.
Appreciate the input! Backed up all the things I've been thinking and trying to solve.