Honda CRX Forum banner
1 - 20 of 21 Posts

·
Registered
Joined
·
101 Posts
Discussion Starter · #1 ·
im planning on doing a swap from my d15 to the ZC (DOHC) and i was wondering if anyone else has done this before (i tryed searching ZC but got nothing, was able to google some OLD posts from here)
but i was wondering if anyone has any life-saving advice, things you didnt realize till you started kinda stuff

i plan on getting out the d15, painting the bay, painting some parts on the new motor and putting it back in in about 4 days tops

new tires, replacing a CV axel then

the rest of my project is to fix the fender (MAACO wants $1900 to do it!), i'll prolly go to a school that does bodywork and see if they'll do it.

THEN the paintjob, and hopefully it should be done.
 

·
Registered
Joined
·
407 Posts
From what I saw with mine (I bought it with a DOHC ZC already in it), all it was is a couple wires, otherwise it bolted right in. If I recall right it's stock mounts and everything. It seemed a lot easier than the B18 that we put in. Also how much did u spend on your ZC swap, like motor, trans, and ecu? I would kinda like to get an idea of how much I can get for mine.
 

·
Registered
Joined
·
101 Posts
Discussion Starter · #3 ·
well, im keeping my HF tranny, and im getting the motor from my bro-in-law (he's building a new one for his civic)

but we talked about it a while before and he asked if i wanted it, an said yeah, a few days later though he actually said hes done with it (has to make sure his other car -tracker- can survive the winter) but he asks what i want from it, an i asked "uh, the whole thing?"

he says "the supercharger too?"

"if your just _giving_ it away..."
HA...shows what i know about actually "modding" cars :p

but currently i dont think hes charging me anything for it, which is DAMN sweet, but even if he does, i'd gladly pay

otherwhise, tl;dr: sorry, i dont know how much it would cost
 

·
Registered
Joined
·
1,960 Posts
if you are doing this for performance i would strongly suggest that you ditch the hf tranny the gearing in it stinks for performance. . .

the zc tranny would be most ideal and then an si tranny but a dx tranny would still be a nice upgrade to what you have in there..

If you change from the hf tranny you will have to swap out the hf axles and hubs for ones from a dx or si.... the zc basically bolts right in.... you aill need to repin the plug for your distributor and run 2 of the wires up to the cam sensor on the top of the zc. . . but other than that it is a direct swap... do yourself a favor and get a different transmission... all that work of swapping it over is not going to yield much of an improvement with out some good gearing to get it moving.

Also you will want to swap to a different computer. . . get something that has a closer fuel map for the zc like a pm7 i think is the zc computer . . . . a pm6 from an di would work.. . . . pm5 from a dx will NOT work.... even a pr4 from a b18 teg would do nicely.. .

other than that. . . . you should be good to go

Chris
 

·
Registered
Joined
·
734 Posts
pandaCRX said:
well, im keeping my HF tranny, and im getting the motor from my bro-in-law (he's building a new one for his civic)
You're going to run the HF transmission on a CRX with a (possibly supercharged) ZC engine? Can I ask why? You might get better gas mileage, but if you were primarily concerned with gas mileage, you probably wouldn't be doing an engine swap. I would seriously consider getting an Si transmission. There are some differences in gears 1-5 (with the Si trans being geared more closely for performance), but the big difference is in the final drive ratio, the HF's final drive is 2.95:1, where the Si trans is 4.25:1.

If you're just thinking about keeping the HF tranny out of convenience, I'd advise against it. You can pick one up for cheap, and it's going to be a LOT easier (and no real extra work) to swap it out during the engine swap than if you don't like the HF trans once it's in the car and have to swap it out with the car all put together.

EDIT: toxiclows beat me to the punch, his post wasn't there when I started mine and I got distracted while posting, haha.
 

·
Registered
Joined
·
2,594 Posts
toxiclows said:
If you change from the hf tranny you will have to swap out the hf axles and hubs for ones from a dx or si.
Not true. The HF axles are thinner and thus easier to break (could be a noteworthy issue with a more powerful engine), but they should still plug into a DX/Si transmission just fine. Though yes, you need to switch out the hub/knuckle if you upgrade to DX/Si axles... It would be a good opportunity to also upgrade to larger '90-91 Civic EX/'90-93 Integra front brakes (they also require swapping out the steering knuckles).
 

·
Registered
Joined
·
88 Posts
paint it yourself or somewher deffinately other than macco cause i went to an auto school and when we got customer cars it worked around out class schudule and even if anyone is in that class just to let you know
 

·
Registered
Joined
·
101 Posts
Discussion Starter · #10 ·
yeah, i was planning to keep the HF tranny just because of its longer gear ratios but yeah i guess it does make sense to go with something shorter i'll look into them (see if he has any, i luv free stuff :p) thx for the advice about matching up the trannys and the computers

but the painting i'll do myself. i made a pretty good looking car in forza and am just going to take that design (wish i could screencap it) but its going to be black with orange panzer-stripes (just googled it, maybe not a panzer, but i seen it on a tank somewhere)

and the bodywork...i guess it got hit in the back and the back left fender besides being wrinkled up, is pushed forward about an inch (i cant put on the black pannel behind the window :( ) i tryed banging it out to a general shape but that didnt work, and maaco says it'll take "18" man hours to REPLACE the whole thing, more to try and bang it out because its now stretched an all that...just lots of trouble.
 

·
Registered
Joined
·
1,960 Posts
bobski said:
toxiclows said:
If you change from the hf tranny you will have to swap out the hf axles and hubs for ones from a dx or si.
Not true. The HF axles are thinner and thus easier to break (could be a noteworthy issue with a more powerful engine), but they should still plug into a DX/Si transmission just fine. Though yes, you need to switch out the hub/knuckle if you upgrade to DX/Si axles... It would be a good opportunity to also upgrade to larger '90-91 Civic EX/'90-93 Integra front brakes (they also require swapping out the steering knuckles).
Ture I 1. was thinking of my b swap where i had the axles from the teg and had to change my hf spindles...
and 2.
was thinking that he would want the stronger axles anyway... . I guess it does work.... I just cant see anyone wanting to risk the smaller axles in there. . . . .

you are correct though . ... my bad. . . .

Chris
 

·
Registered
Joined
·
101 Posts
Discussion Starter · #12 ·
ok i talked it over with him and im getting a si tranny as well, he also said it wasnt that hard to swap out gears (but im not sure im going to do it, but if so i'll prolly keep the 5th gear from the HF, never really use that for "performance" reasons anyway so) so im gonna buy some si axels, and i guess hubs now too, but do the hubs have to be pressed on? is that something i have to send it somewhere to do or could i do it at home?
 

·
Registered
Joined
·
734 Posts
pandaCRX said:
but if so i'll prolly keep the 5th gear from the HF
OK, just for fun I used these specs...http://members.lycos.nl/hendrik/crx/crxtech2.htm and this gear calculator...http://fatboyraceworks.com/gears to figure up how much difference this would make. The real low-RPM advantage of the HF 5th gear is only realized with the HF final drive, with the Si final drive it's probably not much worth messing with. Assuming the default of 195/55/15 tires (doesn't really matter as long as both are equal), the fully stock Si tranny will turn 3288 RPM at 70 mph, while the Si tranny with Si final drive and only the HF fifth gear swapped over will turn 2960 RPM at 70 mph. To me, 300 less RPM at highway speed is not worth the trouble of cracking the tranny open.

The difference in the 5th gears are .771:1 (for the Si) vs. .694:1 (for the HF) by the way...the difference in final drives is much more dramatic, 2.954:1 vs. 4.25:1.
 

·
Registered
Joined
·
779 Posts
baker423 said:
ryan_long_01 said:
If you're just thinking about keeping the HF tranny out of convenience, I'd advise against it. You can pick one up for cheap
If you can FIND a decent Si tranny. I have been searching for some time and still can't get my hands on a 90-91 Civic Ex or Civic SI/ Crx Si transmission.
I have one for sale...and so does my brother. These are pretty common if you hang around a bunch of people with 4th gens lol.
 
1 - 20 of 21 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top