I was wondering if any one has a 20B long block just lying around that they could measure for me. I have this crazy idea to put a 20B in my MR2 and don't know if it will fit. Being the simpleton that I am I figured it would fit since I have the NA version which is a 2.2L, but I figured I should probably be safe as appossed to sorry. Thanks.

 

I don't know the dimensions, but i'm wondering how you are going to mate the 20B to the MR2 tranny?

 

Me too, but I'm more worried about it fitting in the engine bay first. I plan on swapping out the tranny anyways because it's NA and I've heard their tranny's can'y handle a whole lot of power. So I don't know what I'm doing for a transaxle, possibly a NSX or 930 tranny. I don't know yet. It doesn't even matter if I can't get the motor in.

 

To continue in this thread, I have the same question about the 20b engine, however, I am looking specifically for a measurment from the center of the crankshaft to the right hand side of the engine (seen from the transmission side). I need this because it will decide whether it's feasible to mount one transversely, as was intended by the designers. All other measurements don't *look* like they should be an issue.

I am actually a european citroen enthusiast, and I am looking at the feasibility of installing a 20b engine in a Citroen CX, which was originally designed with a 3 rotor in mind (never got into the production version). My dream is for a rotary engined CX (with 400hp, but that's secondary).

 

Are you thinking about using the stock turbines or a single? That will affect the distance. Also are you planning on using the stock intake manifolds? Without manifolds I get 6 1/2" from the center of the e-shaft to the edge of the motor.

-Destin

 

How much money do you have???
Do you have the equivalent of US$20,000 to even start a project like this or extensive resources for all the custom work???


-Ted

 

Thanks for the measurement. I think I have pretty much got space to recess the stock turbines inbetweeen the top and bottom beams of the subframe, which would be the rough starting point to go from.

This is pretty much where it has to fit. Will be a custom exhaust ofcourse:


As for the cash. While I don't have $20,000 just sitting on my bank accounts at this particular moment, I understand that that's at least the minimum size for the investment, and it's worth it to me. It's not going to be finished tomorrow, but the first huge hurdle will be getting a 20b in decent shape to Europe. We'll see from there. The whole transmission question will be interesting too. But yeah, I understand that this will cost about as much as a new car. That's fine.

Nevertheless, this is, for now in the planning stages. I will eventually get this done, even if it turns out only a 13b lengthwise will fit, but the ideal is a 20b transversely. It's a fair bit shorter than the 4 cylinder 2.5liter it's replacing, which gives me room to muck about with the transmission. A friend of mine has a CX with the engine out sitting around doing nothing, and I think I will probably need to build a mockup to see if it can work the way I would like it to.

 

^ Looks like the 20b should fit transversely.

 

Ok, that's what I was thinking too. The main issue then will be the stock sequential turbo's, and whether that can fit. I don't mind switching to (a) aftermarket turbo(s), but that really depends on what I can expect from the stock units. I am looking for ~450hp, are the stock turbo's up to that? I like the idea of a nice constant power delivery, so I'm inclined to stay with the stock turbo's if possible. One more question I need to find an answer to is if I can get away with tipping the 20b forward? Is that likely to cause lubrication problems, and if so, is there a decent solution? This because, as far as I can tell the easy way to fit the stock turbo's is simply to inline the engine forward a bit. Anyway, thanks for the reactions so far. I guess it's time for a mock-up.

 

Tilting shouldn't be a problem with the engine since the oil system is under high pressure. However, you may need to modify the oil pick-up to prevent oil starvation.

 

Were you going to try plugs-up? I'd recommend ditching the stock turbos because they weigh 62lbs. They'd also hang down pretty low. A single mounted in a more convenient spot would be a better choice. The intake manifold hugs the engine (to make room for the crappy turbos) so it shouldn't be a problem in a plugs-up configuration.

 

Hmmm, I take it that twin turbo setup is not very highly regarded here then? I haven't really researched them yet. Are they so bad that it's better to have a single or twin other turbo's? Perhaps twin watercooled T3's or something of the sort? As for "plugs up" I'll admit that I'm not certain what that entails, but I'm hoping you'll enlighten me. It sounds like something I ought to know :-).

I can live with modifying the oil pickup as long as it doesn't get too complex. This project is beginning to look like it may be feasible. Almost too good to be true, if I can get it together.

 

Plugs-up simply means the plugs point up and the intake/exhaust side of the engine is pointing down. Folks who fly their rotaries know a lot more about this than I.

I certainly don't like the stock twins. They weigh too much, are only good power for an automatic luxury cruiser (you would think), and produce and retain heat like a mother. Heck, I chose to run NA until I can afford a large single rather than have anything to do with the stock twins.

Ted got pretty good dyno results running NA. It was surprisingly close the stock twins. I think they were good for only an extra 5HP or something like that. Besides, my application was smaller and lighter than most 20B projects, and the stockers wouldn't have fit anyway.

 

Right, ok... from what I see on the pics of the 20b, it looks like the intake side is generally up? Not that I care about the orientation, as long as it's lubricated I'll go with whatever fits. Those turbo's need replacement then. The current engine, a 2500cc side cam 8 valve turbo has a fair bit of turbo lag with a T3 and intercooler. I understand that I should really compare a 20b with a 4.0 liter piston engine, which would make a set of 2 T25's or perhaps two extra light watercooled T3's the stuff I am looking for. Building the exhaust manifold will be... interesting. But, thanks for the help guys. This is going to be a slow project, first gathering the bits I expect to need as cash becomes available and then the build. I will let folks here know how it turns out. Getting a 20b here in the Netherlands is the first challenge.