New Owner of a 1981 4door VW Rabbit Diesel**47.5MPG**Baseline

[bigchelis]

Originally Posted by Christ

Don't use a glass pack muffler. The soot will clog it in a few days and you'll have a straight pipe lol

If you don't need power brakes, you can delete the booster vac pump. You either open the lid and remove the vanes (they slide out) or remove the diaphragm, depending on which type you have. Its not typically the starter itself that wear out, but the little brass bush that resides at its nose, pressed into the transmission housing. They're a couple dollars. Best to pick up a spare now so you have it. You remove it with a thread tap and press the new one back in very gently with a threaded rod and a nut by tapping with a small hammer.

I was just telling my Diesel Mechanic family member about removing the power brakes, he though I was nuts...

I used to have a 2001 Mustang Cobra which I daily drove with manual brake conversion kit and manual steering. At 3,000lbs it didnt seem like an issue at all, so I wonder if I will even notice much difference with manual brakes.


I purchased a dedicated brake conversion kit for my 2001 Cobra but if I can do this very simply on my rabbit that would be awesome and it would make my engine bay more gutted Does anybody have a link to how this is done?

thanks,
Jose

[Cobb]

The e brake helps for making sharp u turns, sharper regular turns and parallel parking in tight areas.

Never had manual brakes, whats wrong with fully functioning vacuum assisted brakes?

Those 2 red wires up on the firewall by your brake booster is to your glow plugs. That fuse blows over time and can cause them to not work.

Back in the day VW owners waved and honked at each other giving the peace sign.

Thats not the stock muffler. Straight pipe gives better torque on small engines and less to rattle apart.

You using kleen diesel(SP?)? The stuff in the little grey bottle? Yeah, diesels love that. Then in cold, cold winter time the white bottle that include a antigel solvent.

[Christ]

If you want to go with manual brakes, there are some MK1 Rabbits that came without power boosters. You need the firewall plate and master cylinder if you're going that way. Technically the pedal is slightly different too, the attachment point is higher on the pedal for manual brakes.

When I did it on my MK2 Golf, I took a bad existing booster and Mae an adapter plate from it to use a new master cylinder of the stock variety directly against the pedal. In hindsight, after all that work, I'd have been better off just removing the firewall spacer and adding a plate onto the firewall to reinforce it, then bolting the master cylinder direct to the firewall and using a custom length push rod to actuate it. One thing to be sure of is that you are pushing as close to straight into the master cylinder as you possibly can. Pushing to either side would mean eventually damaging the seals and piston.

[Cobb]

Even if you go manual brakes, you can only remove the fins to the vacuum pump to disable it. You need it in place to spin the oil pump as its driven by the intermediate shaft. I guess you could get a dizzy from a gas one and hack off the top of it and clamp it in place?

I think the strangest thing we ever had happen with those cars is the fact the radiator fan comes on many times after you stop or park the car from a drive. Hell, some hot summers Ive heard the fan pop on in the driveway for no reason, then go off a few minutes later.

May want to do the big 3 upgrade or at least add some grounds. You see a lot of these cars with a head light that wont light or it goes off and on or is the reverse of the other one. The electrical system wasnt designed the best, but some extra grounds do not hurt anything.

[bigchelis]

[QUOTE=Cobb;411790]Even if you go manual brakes, you can only remove the fins to the vacuum pump to disable it. You need it in place to spin the oil pump as its driven by the intermediate shaft. I guess you could get a dizzy from a gas one and hack off the top of it and clamp it in place?QUOTE]

Cobb,
I was looking at this yesterday and a gas oil pump might work. This way I can get rid of the entire vacumm pump and not just disable it.

[bigchelis]

I drove another 340 Miles these past 3 days and used up 6.8gallons Thats borderline 49/50MPG.

I only deleted the cold-air and used Diesel Kleen.

I will revert back to cold-air system and put a bigger 2.5~3in straight exausts (debating on flowmaster muffler).

Local Muffler shop is asking for $120 or so just to straight pipe it from header on back with 2.5in. I guess over $200 with a chaep flowmaster. arghh


Best,
bigC

[Christ]

No need to use a gasser oil pump, you can just use the distributor from a gas engine to drive your existing pump. I'm assuming you have the diaphragm type vac pump, in which case you just open up the pump and remove the diaphragm to disable it. The remainder of drag from that accessory is required anyway, no matter what you do (unless you have external oil pump, etc...)

I believe the oil pump from a 1.9 AAZ engine is an upgrade to that one.

Not much else to talk about here.... most of the general stuff seems to have been covered already lol

[Christ]

Also, if you use manual brakes, youl want to disable the pump as it will have no further use other than driving the oil pump. Disabling it will not affect fuel economy by any measurable amount, but it will keep your engine from shooting oil all over the place when the hose connection starts leaking and the pump draws as much air as it can possibly draw and deposits it directly into the engine case.

[bigchelis]

As of right now the car now has a 2.5in straight exaust from header back. Then attaches to a 3in Round Magnaflow Muffler that is 18in long.

So, bigger exaust is done

[aerohead]

The following are from a CAR and DRIVER road test of a VW Rabbit Diesel,reported,November 1979, measured at constant highway speeds (probably at Chrysler Proving Grounds which is just a hop skip and a jump from C&D's office at the time)
__________________________________________________ _______________
80 mph = 27.0 mpg
75 mph = 30.0 mpg
70 mph = 34.5 mpg
65 mph = 41.0 mpg
60 mph = 47.0 mpg
55 mph = 52.0 mpg
50 mph = 57.0 mpg
45 mph = 61.5 mpg
40 mph = 62.5 mpg
This car may be a bit different but the trend line may be similar for the speed differentials.