I am seriously considering putting a d15z1 into my 89 crx si and have a few questions.
1. Will I need anything besides the engine, PO7 ECU, OBD0->OBD1 conversion harness, inner CV joints(depending on which transmission i choose), Left engine mount(different on VX than crx),a way to adapt fuel lines, and an EGR control box from a Vx?
2. I want to keep using a cable transmission, but I'm having a really hard time finding a crx hf tranny. Will i be able to use my current Si transmission? If I do would i lose significant Gas mileage?
3. Is this swap worth doing in a crx si instead of an HF? My model weighs in at 2150 lbs and only currently maxs out at 29.5 MPG(that was with meticulous to gas mileage driving) and averages around 27 MPG.
4. Does anybody know a dealer that sells HF transmissions cheap in or near NY?
Funny you mention fuel lines. This is something I actually took care of just yesterday. And let me say that it was no problem. Now I know that much has been made about adapting fuel lines. I even saw one page where someone talked about cutting and soldering. But none of this is actually necessary. All you have to do is bend the end of the stock VX fuel line where it connects to the filter. On the stock VX line, there is about a 90 degree bend. So the line interferes with the filter. But if you wrap the banjo fitting in paper towels, insert it into a steel pipe, and put a little muscle into it, you can easily bend it enough that it clears the filter. MUCH easier than trying to graft on different fittings.
Anyway, as far as the car itself, you can certainly use your SI. But there are better choices here. For instance, the 1988 and 1989 CRX HF models weigh in at 1819 and 1834 pounds, respectively - more than 300 pounds lighter than the piggish 1991 SI (which actually weighs in at 2174 pounds!). And if you can't find one of these, the 1988 DX weighs in at 1922 pounds, but is VERY easy to bring down to 1988-1991 HF weight (1989-1991 DXs are MUCH heavier). Even the 1990-1991 HF models only weigh 1967 pounds. Of course, this weight difference is going to be more of an issue during city driving or driving in hills than freeway driving on level ground. So it may or may not be a big deal for you. You also have to consider the availability of one of these cars in your area, as the older HFs can be REALLY hard to find. On the other hand, a 1991 SI in good condition can certainly yield some good cash. So you just might come out ahead if you should decide to sell.
Where i live crxs arent very common, any that i do see listed are way overpriced and have an integra engine shoved in them(not my cup of tea considering there's much faster out there) I would only buy another crx if it had a dead engine and or cost next to nothing, but like i said its slim pickings here all prospect cars would cost much more than work on my own car.
My cars body is rust free and the Si motor in it would easily run for another 100,000 miles, but to be honest im looking for a worthwhile car project.
If i could almost double my gas mileage and still have a car that handles great in all weather then it would be worth it. The question is can i do this within a reasonable price range...
I am now a little discouraged by the fact that if i got 45 mpg out of this swap i would only get back around 450$ per year in gas savings meaning if this swap costs me 8-900$ id have to drive the car a full 2 years to get my money back(at worse case scenario of 4$ per gallon).