DPFI/MPFI difference overated?

Well as some of you may know my egine still uses the glorious dual point injection system..Well I've been planning on doing the swap I've just been hesitant because my car is my daily commuter to work and I don't wanna run into probs. with it. Well anyways..my brothers friend got a black 91 si and they were over so I asked him if we could take it for a spin well long story short: he let me drive it and I couldn't really feel much of a difference from my car...Does it really gain that much over dpfi?

also si's are heavier.

well yeah they are heavier but from what I've read the multi point is supposed to be much better for preformance and It just didn't even seem different..the only thing I noticed was his intake sounded cooler. But driving his car seriously made me reconsider doing the swap for now..But someday when I'm rich and famous (lol) and I get my b18b swap I'll have to do it anyways I guess...=/

ur motor may be stronger then his and muti port will help you out

His car could be in need of a tune-up bad. Also, you can think about it this way... with your DPFI you have two injectors - one main injector and one that is used to squirt more fuel when needed in high rpms (somebody correct me if I'm mistaken) so it's like somebody else said "a modified carburator"... which is nice I guess for a 1.5 and good gas mileage, but even a 1.5 will run stronger IMO with 4 injectors squirting into each intake plenum/runner going straight to 4 cylinders. I'm sure if you had mpfi you'd notice a difference in your car's performance.

yea, lots of people have done the swap and i've only heard good things about it, and decent power gains (compared to other bolt-ons anyway)

si arent that heavier. theres like a 75 pound diffrence.thats from the sunnroof ,a/c and rear disc.

20hp is definitly not over rated.

plus the only mod that will get you the same whp gain on DPFI as on MPFI is direct port nitrous.

edit: because of the tiny ass TB

I did my mpfi swap about 3 weeks ago now, and im not disapointed at all. it took me about 11 hours to do but it started on the first try. I lost Gas mileage but who cares! its still a civic and the power gain is well worth it.

I gained milage, alot, went from low to high 30's.

yeah I will probably still do the conversion..I'm just putting it off. I drive my crx about 80 miles round trip everyday and the mileage is just awesome. + I the wiring is scary to me, I don't wanna F--- with it and not get something right..and have my car not running right. And in MT there is no shops..(just your basic "erls truck repair" mechanic shop etc. lol) that I could pay to make sure it's done right. anyone near mt who's done the conversion? :D

when your rich and get the b18b swap, your still gonna need to convert to multi point ;)

You shouldnt be worried about the wiring. I found when i read those how-to's i never found a good one, every one i read, had at least 1 of the steps not worded right. so i found about six of them and took steps from each one to piece together a clear guide that made sence to me. I'd say the hardest parts i had where: the middle bolt on the bottom of the manifold( a little tricky), how to depin the wires at the ecu(tricky ,but when i found the secret it was easy) , and the vacume lines(again not hard, but i had to find a vacume line diagram for the si). everything else went smoothy. if your serrious about doing it i'll answer any questions you have. everything is still fresh in my mind about it.

i converted to mpfi with a zc attached, i was VERY happy with the gains :evillol:

You shouldnt be worried about the wiring. I found when i read those how-to's i never found a good one, every one i read, had at least 1 of the steps not worded right. so i found about six of them and took steps from each one to piece together a clear guide that made sence to me. I'd say the hardest parts i had where: the middle bolt on the bottom of the manifold( a little tricky), how to depin the wires at the ecu(tricky ,but when i found the secret it was easy) , and the vacume lines(again not hard, but i had to find a vacume line diagram for the si). everything else went smoothy. if your serrious about doing it i'll answer any questions you have. everything is still fresh in my mind about it.


whats the secret to de-pinning the ECU? i havent found that out yet

Pin extractors?
get aviation pin extractors from aviation tools on E-bay

whats the secret to de-pinning the ECU? i havent found that out yet

with the plug out of the ecu there are two white clips sandwitching the wires. to get those out one at a time you have to press the little tab things in on both sides at the same time and you can slide the clip completely out, like bread in a toaster, (wierd analagy, but kinda makes sence). then take a mini flathead screwdriver and stick in the middle row of holes from the front of the plug and press toward the wire your talking out. that will push up a tab and allow the wire to slide out. hope this helps.

sewing needs work good, they fit over most all pins and press the little tabs down so you can slide it out.

i tried sewing needles and gave up after 2 hours

derek- you have to use the big hollow ones, they slide right over the pins, theres no way to mess it it up lol. I think people are trying to use the small solid ones. Piercing needles work good, 12G will usually slide over them. If you grind the point down where the whole shaft is flat on both ends it works better (on piercing needles and sewing needles).

oh yea, i dunno, i just said fuck it, added connectors and stuffed it into the empty slots, was a hell of a lot faster then de-pinning it haha :evillol:

what about just cutting the wires. As long as you made sure it went to the right one and was done right witha soldering iron wouldn't it be fine? I really don't wanna depin the damn thing.

It might be hard to fid in your area, but the harness(Inside cabin and engine bay) from a hf or si is easy to swap. Thats what I did.

swapping the entire harness? Is that even a option? Wouldn't that just be a big pain in the ass..?(sorry i'm tired and my brain is shutting down)

GIT-R-DONE
i went from a 89 base civic to a 91 si, it was like night and day difference, besides the fact that i had one of the slowest civics made minus 92-95 vx, go for the mpfi, my mileage is alittle less then the base but only by like 4 or 5 mpg