Hey: I just got a '72, originally a 1.7 w/ FI still in place. Blows about a quart of oil every 5 miles (really!), and I have a (sold to me as good) 1.8 FI motor , which I'm going to put in. Some FI parts for the 1.8 are missing, so I'm going to use the 1.7 FI stuff that's already hooked to the computer in the '72, with a set of 2.0 injectors. I've been told that all the 2.0 FIs are like the old 1.7, so the change to 2.0 injectors will enable it to function with the 72 computer (the 1.8 was running on its FI when pulled out of its car.) WHAT blips or surprises do I need to look out for??
One pro mechanic said: since the 1.8 has a gasget /seal at the filler, and a PCV, I should remove the pcv and 7aa5 or 76 oil breather assemblly with the large diam vent fitting attached to the air cleaner. OK--I can do that. (And, yes, I have headers and mufflers from both, and can get a new mufler hanger or modify the old if needed.
Anyone else got any good thoughts or hints?

Other people will chime in, but what you are doing will probably NOT work. The FI systems on 1.7's and 1.8's are almost TOTALLY different! Unless you really know what you are doing, I would not attempt this!!

i may be wrong, but i think you cannot put 2.0 pistons on a 1.8; something about the wrist pin height. one reason i say this as you see advertised 96mm pistons and there is a set for a 2.0 and a set for a 1.8. could it be the stroke or ... ? rod length? stroke? again, i may be wrong.

He talking about 2.0 injectors, not pistons.

DOH! (again)

Try it first with the stock 1.7 injectors. The diffference in CC isn't that huge (1679cc for the 1.7, 1793cc for the 1.8), so I think the stock EFI would cope. You might bump the fuel pressure up a couple of PSI, but I doubt anything more would really be needed. It would be prudent to check with a WBO2 (wide-band O2) meter just to make certain the mixture stays reasonable throughout the RPM/load ranges.

Be prepared, though--the low-compression 1.8 made less power than the high-compression 1.7 did. At least you'll be able to use regular-grade fuel with no worries about preignition.

--DD

Or could could luck out and get the low-compression 1.7



I'm a FI fan all the way, but I dont have much respect for D-jet, especially when its daily driver status. I like L-Jet but thats just me I suppose.

What parts do you need? I can make things like resistor packs, etc...

When I first got my 1.7 (long ago ), it was running 2.0 injectors on the 1.7 D-jet. Not sure what (if anything) the PO did to make it work, but it worked fine.