dpfi to mpfi: compataility issue

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ezcruiser

New Member
***Updated w/pics*** DPFI to MPFI: Issues

Okay, a little introduction to my situation.

I purchased an 89 SI a while back for super cheap because of some motor issues, mainly leaking oil. Before I had time to work on it I had a good friend in need come and ask if he could buy it off of me because at the time I had three EF hatches. So, long story short... After I preached about the oil leak and how you had to constantly check the oil level, I even made it a buyer's agreement, but he drove it without checking the oil level...
Can you say friction weld?
Locked dead.

So he gave me the money back and money to get myself a motor. I haven't had much luck locating a good stock A6 to buy, so I purchased a D15B2 just so I can get the car back on the road.
I pulled the A6 yesterday and swapped most everything over to the B2.
Basically starting with mpfi and just implanting a dpfi block. I have A/C in this car and wanted to keep it so, for future reference: The B2 A/C mount will not work with the compressor in the SI, you have to use the mounting bracket off the A6 motor or the pulleys will be about an inch off from alignment.

Pictures of the brackets with their obvious differences:

Note: In order to fit the SI compressor onto the d15 motor you have to use the PM5(SI) bracket, the one on top in the picture.





Now, my most recent/important problem is the motor is idling at a cool 3k rpm and blows some white smoke(water/coolant entering combustion chamber)...

Here is what I'm thinking, When I applied the A6 intake manifold to the B2 block I decided to see if I could get one of the manifold braces to mount up. The A6 came the closest, a smidgen too long, but I used it anyway. ***EDIT: The B2 intake manifold mount was a little further off and only took 3 bolts instead of the A6 mount, boasting a wild 4 bolts.*** But, I'm thinking it being too long is the cause. The brace is putting upwards pressure on the manifold causing the coolant to leak into cylinder #4, thus the by-product of white smoke. Gonna check it out tomorrow. I will elongate the holes, more is better in this case, in the support, so I can still make use of the support.

UPDATE***
Here are pictures of the IM support bracket, the holes were slotted roughly 1/2", I went and drilled an extra 1/8" inward on each slot. I also have a picture showing the 3 bolt D15 support and the 4 hole D16 support.





I have some pretty good pictures, I think, of the swap and could eliminate coolant routing problems, A/C PM5 and PM3 bracket comparison, wire routes and who knows it may inspire someone else to take on the dpfi to mpfi project? Anyhow I will have some pictures up before long. Thanks for reading!

09-04-08 - I slotted the holes and extra 1/8" towards the center of the bracket. The bracket fits easily and the smoking/fast idle has stopped.
Now I'm having a problem with the clutch or trans. When the clutch pedal is to the floor it is fine with no noises but as soon as I let off the clutch I hear a scrubbing noise that sounds like old dusty brake pads on old rotors, if you can imagine that... It makes the noise in neutral with clutch disengaged, and while in a gear, driving. Haven't researched it yet, don't worry fixing to use the search button... I have a couple ideas though, through out bearing and pressure plate housing rubbing, not sure. Will update later.
 
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good thread, in for the pics and further developments. there are lots of threads on this conversion here, a search will turn them up.

good luck with the swap/conversion! :)
 
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I have the dpfi IM but the car is mpfi, so I stripped the A6 block from the car and implanted the D15B2 in the car with mpfi. So there really is no need for the B2 manifold. Plus I wouldn't want to change the wiring from mpfi to dpfi, I think we just had a small misunderstanding.
 
I was under the same assumption as well. Thanks for clearing it up.

Are you still sourcing out an A6? Or are you thinking of swapping another motor? Possibly a Z6 swap?
 
I was under the same assumption as well. Thanks for clearing it up.

Are you still sourcing out an A6? Or are you thinking of swapping another motor? Possibly a Z6 swap?


Awesome, glad it helped. I can't wait to go get my camera cable in the morning and load up the pictures. NO laughing!

Well, George777, not sure what I'm going to do... I have a b18a1, but I would like to save it for something else. I have also entertained the idea of a b16a. Who knows, if I find a good deal on a z6 or something, never know! I may keep you posted here!
 
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