Resurrecting an old thread here. I wanted to say that I was wrong, the Tranny does in fact start in FIRST . I just thought that was second because it didn't feel like first gear and felt, well , more like second. Not enough take off at all.

So once again, how can we improve acceleration? Over the last few months I have worked on the car making sure everything is "tuned up" and it is, it's a very well running machine, but I just wish I had a little more "oomph" like another gear or something. The other thing is on the highway I feel like it revs high. So I think I want another tranny. a 5 speed or 6 speed. doesn't have to be a manual , could be an automatic. I just want a little more performance. Maybe a quicker spooling turbo.

I'm just trying to steer up some thoughts here.

You've got 123 hp at 4400 rpm. During normal operation, running 2000 to 3000 rpm, you've got between 45 hp and 95 hp. You're not ever going to get to a point where it can keep up with the 200 hp gassers. You can spend a fortune of money and possibly get another 25 hp. Then, you'll have a whopping 150 hp at 4400 rpm.

Still cannot beat a four cylinder Honda Accord.

If the performance isn't satisfactory after you have properly set cam timing, IP timing, and boost...........sell the vehicle and buy one with more horsepower.

BTW, the reason that it revs somewhat high on the highway is so that the engine provides you with sufficient horsepower for passing and for climbing hills.

Brian,
I am trying to conjure up some ideas to improve a great engine / vehicle. I am not selling this car. I want to intelligently / practically / "bang for buck" modify it.

I'm just looking for ideas here guys.

I have some ideas, like a modern quick spooling turbo with a big downpipe/exhaust.
Maybe a tranny swap. What other engines have the same bolt pattern as the 617?
Maybe a differential change. Maybe propane injection. I don't know I want to hear everyone's ideas and I want to discuss. I think there is some serious potential if you think about it?

Define "serious potential" and I'll provide you with the cost to achieve same..............then you'll reconsider your options.

try some nitrous:D

There isn't all that much modification potential in the 617 engine. It's just not designed for outrageous performance. It doesn't have a crossflow head and it only has 10 valves. Get an E300DT or a CDI if you want easy performance. Or if you like to tweak, get a 300SDL with a good 603 and start playing with the full load screw+pyrometer and maybe in intercooler. Anything can be done with the right amount of money, but the question of practicality arises.

Super performance on these engines does not come cheap. Everything you can easily do with stock components and easy mods have already been outlined.

Nitrous won't help much at all. Remember, diesels operate on the principle of excess air, so adding more oxygen (which is what really isn't going to do much unless you can provide the fuel to make use of it. Same goes with the boost...sure, you might be able to [dangerously] get 20psi out of your stock turbo, but all you'll be doing is drastically heating the intake charge and endangering stuff like your head gasket. Unless your IP is modded to provide more fuel (and that opens up the whole EGT can of worms), more air isn't going to do any good.

You could use nitrous to get up to speed, put the alda to full fuel, and then just add nitrous. instant oxygen more horsepower at low speeds, then you let off on the nitrous at high speeds. Basically the alda is crap just to make the engine burn abit cleaner. might save a very minute ammount of fuel in the long run. all it does, is when there is a low ammount of boost. the alda limits the ammount of fuel that can be injected. then when boost comes up, the alda allows more fuel to be provided.

this was the best explanation of Bowden cable adjustment I could find.

I am currently returning ~18 mpg... and I drive rather gently.

Besides a twitchy front end and a somewhat dragging front caliper, I cannot justify this terrible mileage.

-Engine has excellent compression
-trans is responsive but shifting improperly
-valves, timing and engine mechanicals are set.

Since the recent timing I did, I have not been able to set the linkages very well. (FSM sucks for '85 cali engines) Could they cause poor mileage to this degree? Could the trans Bowden cable cause this as well?