'89-91' Federal HF Transmission swap into a Federal '94 Honda Civic VX

[1994CivicVXHB]

I was wondering has any done this, found plenty of folks that has taken their HF and put a D15z1, What about taking the Federal Hf Transmission and putting it into the VX. As per previous research done on this swap, I should technically be able to maintain lean burn at 80 MPH as RPMs are less than 2500 at that speed. Don't know how much of an improvement this would be over an original Civic VX tho...

Basically, I need to know exactly what is needed to complete this swap as I know that the HF trans is cable while the VX trans is hydraulic. I heard that the trans mount is different and the throw out bearing actuation is different.

There are some conversion kits but I don't know too much about which one I need for what I want to do. Here an example:
B/D/H/K Series Cable to Hydraulic Conversion at Innovate Mounts
It would be nice if there was a used one of these for sale....it is quite expensive.

[EF TuneRR]

Those Innovative Mounts Conversion kits are just that; conversion kits to allow a car that originally came equipped with a cable transmission to utilize a newer hydraulic transmission. Hence the name, "cable to hydro". The kits are just a bolt-on mechanical linkage that allows the older cars' clutch cables to actuate the hydraulic operated transmission. I will tell you right now, these will be of no use to you for what you desire.

As far as I know, there is no readily available bolt-on kit to go backwards. That is, hydro to cable.

I know that with the B-series transmissions, it is possible to swap gear sets from the newer hydraulic B-series transmission to the 90-93 YS1 (Integra) cable transmission.

The 90-93 YS1 is the ONLY B-series cable transmission that can accept the newer hydraulic gear sets. This is because the other B-series cable transmissions use a smaller diameter input shaft and a smaller housing. The YS1 transmission is the only cable transmission with the same size diameter input shaft and housing as the newer hydraulic B-series transmissions.

That being said, let me make some things clear to you:
-Your car is operated using a hydraulic transmission (you already know this).
-Make things easy (and less expensive) on yourself and KEEP IT THIS WAY.
-It will not be a simple transmission swap. You will need to mess with the internals.

You will be better off trying to install the HF gear set into your original VX transmission and using that in your car.

I'm not sure it's even possible on the D-series trannys, as I've been a B-series guy the majority of my Honda stint. I would think that it is possible to swap the internals from the cable HF to the hydro VX tranny. I'm not sure what is required, though. You will need to do some research to see what is needed to make this happen.

You might also be better off doing just a final drive (FD) swap to your current transmission. You'd have to go aftermarket if you go this route, as the HF and VX both have a 3.25 FD (the lowest of all the D-series (As far as i know)).

To be honest, after comparing the gearing of the two transmissions, I don't think it will be worth the money (unless you can get everything DIRT cheap and do the work yourself). The two transmissions are relatively comparable, with the VX being 3-5mph lower in gears 3 and 4. Gear 5 is essentially identical (close enough to it). You'd be better off getting a different aftermarket final drive, but good luck finding a lower one.

[rountreesj]

Hf has like a 2.98 final drive!!!!

[turbothrush]

Originally Posted by EF TuneRR

Those Innovative Mounts Conversion kits are just that; conversion kits to allow a car that originally came equipped with a cable transmission to utilize a newer hydraulic transmission. Hence the name, "cable to hydro". The kits are just a bolt-on mechanical linkage that allows the older cars' clutch cables to actuate the hydraulic operated transmission. I will tell you right now, these will be of no use to you for what you desire.

As far as I know, there is no readily available bolt-on kit to go backwards. That is, hydro to cable.

I know that with the B-series transmissions, it is possible to swap gear sets from the newer hydraulic B-series transmission to the 90-93 YS1 (Integra) cable transmission.

The 90-93 YS1 is the ONLY B-series cable transmission that can accept the newer hydraulic gear sets. This is because the other B-series cable transmissions use a smaller diameter input shaft and a smaller housing. The YS1 transmission is the only cable transmission with the same size diameter input shaft and housing as the newer hydraulic B-series transmissions.

That being said, let me make some things clear to you:
-Your car is operated using a hydraulic transmission (you already know this).
-Make things easy (and less expensive) on yourself and KEEP IT THIS WAY.
-It will not be a simple transmission swap. You will need to mess with the internals.

You will be better off trying to install the HF gear set into your original VX transmission and using that in your car.

I'm not sure it's even possible on the D-series trannys, as I've been a B-series guy the majority of my Honda stint. I would think that it is possible to swap the internals from the cable HF to the hydro VX tranny. I'm not sure what is required, though. You will need to do some research to see what is needed to make this happen.

You might also be better off doing just a final drive (FD) swap to your current transmission. You'd have to go aftermarket if you go this route, as the HF and VX both have a 3.25 FD (the lowest of all the D-series (As far as i know)).

To be honest, after comparing the gearing of the two transmissions, I don't think it will be worth the money (unless you can get everything DIRT cheap and do the work yourself). The two transmissions are relatively comparable, with the VX being 3-5mph lower in gears 3 and 4. Gear 5 is essentially identical (close enough to it). You'd be better off getting a different aftermarket final drive, but good luck finding a lower one.

I am no expert but......Would this not work for the original poster ?

HASPORT B-SERIES CABLE TRANNY MOUNT 92-95 CIVIC EGBCC | eBay

[steffen707]

Glad I found this thread. There are no kits out there to put the cable transmission into your hydro transmission chassis; however, you can swap the final drive and probably some of the other gears if you want. If you visit an online honda gearing calculator like Honda Transmission Calculator by ZealAutowerks you will see that there isn't much of a difference in the 1-5 gear ratios. The magic of the HF is the final drive as somebody pointed out. Note that Honda Transmission Calculator by ZealAutowerks doesn't have the right final drive. Its actually 2.98 for the federal HF final drive.

Don't be fooled into thinking that lean burn will automatically happen at 80mph because you will be at 2500. The ecu takes into account your throttle position as well. You might find that you get better gas mileage in the city and lose mpg on the highway.......BUT THAT DOESN'T MAKE SENSE YOU SAY.

If you have a higher final drive, your rpm at highway speed will be less, the car will make less power. If the power the car is making in lean burn isn't enough to overcome the aerodynamic and rolling resistances you are seeing in the car, it will drop out of lean burn.

Much like putting a vx engine into a heavier less aerodynamic car, if the engine can't make enough power in lean burn your mph will decrease, you step on the gas pedal harder, and then BOOM, the car drops out of lean burn and you're only getting 35mpg at 65mph.

The only way to tell if this will benefit or not is to do a real world test, or to hear what somebody else has experienced.

I was wondering the same thing. But I was thinking this, with 165/65/14 re92 insight tires, and given the HF 4th gear .823 and 5th gear .694 and final 2.98, at 2387rpm in 4th gear you would be at 65mph.

Now in the VX gearing of .702 5th gear and final of 3.25 at 2220rpm you would be at 65mph.

So I was thinking of swapping in thed 4th, 5th and final of HF into a VX trans and then for 167 more rpm, you would be at the same speed in 4th as you would be in the vx in 5th.

So in case the HF final drive is just too much for the car, you can still get almost the same gas mileage as before with 167 more rpm and the new HF 4th gear and HF final drive, but in city and like everything below 50mph, would be much better off with the longer HF final drive and new HF 5th gear. I just don't know how much that 167rpm is going to hurt the fuel economy if you do have to be in 4th on the highway.

Thoughts?