View Full Version : auto to 5 speed conversion for a 1997

07-07-2009, 10:09 PM
My buddy is selling me a cheap preulude that needs a new tranny(auto) but i wanted to do a 5 speed conversion

how much am i looking to spend for a auto to 5 speed conersion for a 1997 prelude?

labour + parts and who can do it?

07-22-2009, 06:17 PM
price of parts all depends on if you find a doner or not.

if you don't have the skills to do it yourself, expect to pay more than what the car is worth to have a shop do the swap.

any mechanic in calgary will do it, the question is how deep are your pockets.

if you are in the market for a "cheap prelude" that already tells me you cannot afford shop labour for a big conversion job.

and if you are an enthusiast, the question you should be asking is how hard is it to do yourself and what parts do you need.

07-22-2009, 06:25 PM
every point on this list is probably 300$ shop labour

Removing the transmission from the donor car-
(*) Clutch Pedal/master cyl.:
- I stripped the wiring harness back, and clipped the wires to the pedal, so I had enough wire to work with (atleast 2 feet per wire)
- I drilled out the tac welds on both mounts for the clutch pedal, so I would have the correct spacer, and the upper mount. However; I found that the top mount wouldn't work well, as I couldn't properly bolt the back end in, in my car. I ended up using a piece of channel iron, about 1.5" high, and ran a bolt through it, and bolted it to the area under the windshield wiper motor. It turned out to be very heavy, and I really can't see it braking (1/4" steel channel iron)
- When I got past the master cyl, I had some major issues pulling the hyd. line that connects the master cyl to the dampener. I ended up bending the hell out of it, to get it out, but luckily I didn't kink it. I used a pipe bender made for 3/8" copper pipe, and it seemed to work out perfectly.
(*) Misc Parts:
- The donor car's exhaust system was rusted solid. I mushroomed 3 14mm sockets, before I ended up just hacking the exhaust system off.
- When I went to pull the shift linkage, it was ran through some tight spots behind the intake manifold, so I ended up removing the rear engine mount to get it out- CAUTION- MAKE SURE YOU PUT BLOCKS UNDER THE ENGINE BEFORE LOOSENING THE REAR ENGINE MOUNT BRACKET! (I ended up busting the IM, because the engine fell on it when I broke the last bolt loose. LUCKILY the IM stopped it before I got a face full of oil pan!
(*) Transmission:
- The transmission came out fairly easily for me, after clearing the bolts out, and all of the hardware, it helps to loosen the front engine mount bracket from the engine, so the engine hangs an extra inch or so lower. After that, just pull the transmission out, push it forward (still on the clutch splines, with the clutch arm sitting above the frame), rotate the back of the transmission down, till the shift arm clears the rear frame, then push the transmission back, till the clutch arm clears the front frame, and it will finally be clear.
- One thing I would like to add, is make sure you take the stud bolt out; the one with a 7mm hex head on it. If you leave it it, you will skin it along the frame as you drop the transmission, and render it useless, as you will never get the nut back on it! (However, the local honda shop happened to have a couple of them on hand, for $6.85 each)
(*) Clutch/Flywheel:
- I had to take the clutch apart, because I didn't have a replacement flywheel onhand. the stock H22A4/M2Y4 pressure plate has some funky bolts on it, that require a 8mm 12 point socket to get off, and I would highly reccomend using a 1/2" drive socket, or impact-rated socket, as these bolts are extremely tight after 130k miles. make sure you don't bend the bolts if you plan on using the same flywheel; with a bit of WD-40 and some time, they will eventually come out.
- The Flywheel gave me even more problems. I started by using a breaker bar on the other end, to hold the camshaft, but the socket kept slippin off, so I ended up marking and grinding a 5/8" piece of steel to match the outside of the flywheel, and used a couple of transmission bolts to hold it in place. making this piece took me the better part of a day.. now that I've done it, I would seguest wedging something behind the breaker bar on the belt side of the cam shaft, so it stays there as you work on the flywheel bolts.
- Flywheel Bolts: Same as the clutch, you will need a 17mm 12 point socket, with either a 1/2" drive, or impact rated. These bolt heads are very short, and they round off VERY easily... take your time, honda wanted to sell me a set of 8 for $85.
(*) Transmission Wiring:
- I stripped the engine wiring harness back, and clipped the reverse light connectors off as far back as I could get without damaging the harness incase I needed it
- The VSS on the auto and the M2Y4 are different, but the port on the transmission are the same... when you pull your auto out, pull the VSS off of the auto transmission, you will need it! Otherwise, you can just use the manual one, but you will have to do some fancy wiring. (wiring and me don't mix.)

Removing the auto transmission from my car:
(*) Disection:
- I pretty much used the helms 100% for this, with a few breaks to change out other parts (AEM fuel rail, swapped IMs for one that I had drilled for direct port injection, re-routed alot of vaccuum lines, to a "custom" vaccuum chamber (2"x2"x6" aluminum block, drilled from end to end with a 1.5" bit, with misc ports tapped into it; cleaned up all of the random hoses sticking out of the im, and ran them underneath the IM; makes it look ALOT cleaner, but now the IM has a ton of plugs on it, allover the place lol))
(*) Transmission
- following the helms to the letter, the auto transmission dropped VERY easily, and as it turns out, was too heavy for my makeshift transmission jack, and bent it all up, and cracked the transmission housing when it hit the concreate. One thing to note, be very carefull with the torque converter bolts, I swear to god those things are made out of copper, they round off VERY easily; but can be snapped off with vice-grips and a hammer.

Installation of M2Y4 transmission in an auto prelude-
(*) Wiring:
- I did this part last, but you really should do this part first. clip or tape up all connectors except for the AT Gear Position Plug, and the VSS. I personally clipped the wires clean out of the harness. On the AT Gear Position Plug, your going to use 2 of the wires for the Reverse Switch; and the VSS is going to go to the VSS from the AUTO transmission. I highly reccomend using the VSS from the auto transmission, to reduce wire splices in the engine bay. This is the last place you want questionable connections, or risk the wrong wires opening.
- For the Reverse switch, you need to connect one of the wires from the transmission to the WHITE wire, and the other to the Red/White wire that goes to the A/T Gear Position Switch Plug. I highly reccomend using a soldering gun, and some shrink tubes to seal the connections. The engine compartment is a bad place to risk having bare wires. Also, don't forget to zip-tie or tape the wires to one of the existing harnesses, as the engine rocks ALOT when you shift. You can't see it when your driving it, but that baby moves a good 4". Don't risk getting one of your wires pinched when this happens; after your intake is back together, you won't be able to see any of the wiring, to see if it got pinched.
(*) Clutch:
- Same applies as from removing the flywheel, but for the A/T plate, I just used a piece of flat stock and a couple of transmission bolts to hold the torque converter plate; as I didn't really care if I bent the plate.
- Installing the flywheel is best done from below, as you will have enough room to stand in the empty hole where the transmission was; and trying to hold the flywheel in place from the top is hard. that thing is heavy, and needs to be placed very accurately on the little peg on the crank shaft. Take your time, if you bend that peg, or shave it off, your in for a very long week to replace the crank shaft.
- Alignment- I tried one of the plastic alignment tools to put the clutch on correctly, but when I tried putting the transmission on, it wouldn't fit. As it turns out, your better off with a wooden dowel, and a rubber hammer, and align it by eye. the plastic alignment tools bend too much, and 1mm off means the transmission won't seat.
- Clutch Pedal- Cutting the hole for the master cyl was very hard. I tried with a dremel, but burnt the motor out inside of 15 minutes. I ended up putting the clutch plate in place from motor-side, marking it, and using a straight-edge screwdriver and a hammer to "rip" a hole through the firewall. I then used a second dremel to grind the edges smooth, drilled holes for the screws (smaler than the holes on the plate, so the master cyl. bolts would stay in place while I tightened them down) I ended up with a slightly crooked clutch pedal, but I just bent the arm on the clutch pedal with a vise and a sledge, so it sits in the correct spot. Next, I tried to use the top bracket from the donor car. I got the front edge of it bolted in place, but couldn't get a bolt in the rear edge of it, as the area above that end, is where the windshield meets the firewall and the top edge of the dash. I ended up taking a 3" piece of 1.5"x1.5" 1/4" channel iron (C-beam), drilling a hole through the top and bottom, and running a bolt through from the little divit below the windshield wiper motor, through the C-beam, through the mounting hole on the clutch pedal. I used one of the suspension fork bolts from the donor car, and on top, a piece of 2"x4" 1/2" flat stock, to keep from ripping the tin where it was bolted to. It came out WAY too strong; I could have gone with alot lighter material, but that is one area that I won't have to worry about in the future.
(*) Clutch Hyd. Lines:
- Don't feel bad, this part took me the better part of a day. the main line that runs from the master cyl to the dampener was a nightmare. I ended up disconnecting the throttle lines, brake vac. assist line, and unknowingly the engine coolant line that runs to the heater. (figured it was just another vac. line!) After getting the firewall clear, I re-loosened the engine mounts, and lifted the front of the car by pulling the engine forward. This gave me enough room to fish the line through what I couldn't move. I also ended up having to unbolt the evap cyl, to slide the line under it; and I beleive I messed something up in the evap system (more on this later). Once you get this line in place, don't bolt the dampener in until the transmission is in! I ended up doing this part with the transmission out, and had to remove the dampener again, to get the transmission in. Also, anywhere that the clutch line touches anything, you might want to either bend it around it, or wrap it with some foam tape (I used that stuff that you put in house door seals); to eliminate vibration noises, and to eliminate the vibrations from wearing through the clutch line.
(*) Bleeding:
Yes, I did my fair share of bleeding during this whole operation; but that's not the kind of bleeding I'm talking about. I read where tons of people said to use a vac. bleeder; but I went ahead and tried my way anyhow. I had a friend dump brake fluid in the clutch res; while another friend pumped the clutch, and I loosened the line where it attatches to the slave cyl. once I started getting brake fluid on my end, I fully depessed the clutch slave cyl, and let it fill up with fluid before tightening the hyd. line down, while my friend was still pumping the clutch. Immediately, the clutch worked perfectly. I might have just been lucky, or I will have problems with air bubbles in a few years; but since the swap, I've put 1500 miles on the transmission, and have yet to have any issues with the clutch.. so I say conventional bleeding IS possible!
(*) Misc. Things that go ZAP in the night!
- I cannot stress this enough... all of those wires that went to the auto transmission need to be snipped, or taped to the wiring harness! These things get pinched between the transmission and the frame, or melt from hanging next to the exhaust, and ground out, and blow fuses! Whatever you do, don't let them touch eachother! I dis-assembled the wiring harness, and completely removed these lines; as even with the TCM removed, still had +12VDC for some reason!
- If you didn't do the wiring before you put the transmission in, be prepared to do some wiring in very tight spots. I had to do it this way, and it sucked nuts.

Final Wiring/Electrical Info:
(*) Clutch Pedal:
- Fully depressed switch goes to the GRY wire that runs into the immob. unit. clip the other end of the grey wire, that used to go to the A/T Park/Neutral circuit, as this wire will be open after removing the shifter. The other end of this switch needs to go to a ground. A8 (BLK wire) on the Immob is a great ground for this.
- "Tap" switch needs to go to the cruise control module. Pink wire to pink wire, other wire to ground. Pin 3 (BLK Wire) coming from the cruise control module is an outstanding ground for this.
(*) ECU:
- If you have a 5 speed ECU, tie the 2 wires (pins 30&31) that went to the TCM together; as leaving them open seem to cause surging idle, even with a manual ECU... no clue why or how, but hooking them together seems to work. Also, use some elec. tape, and tape the TCM plugs to the wiring harness, to keep them from ratteling around under the ECU plate.
(*) Getting it started:
- After you think everything is in place, make sure the shifter is in neutral, and try to start it without the clutch pedal down. make sure the IMMOB light does't flash quickly (refer to the helms manual to see what different flash rates mean). The engine should not crank, until you fully depress the clutch. if nothing happens when you press the clutch, use a continuity tester, and make sure that the grey line going to the immob. unit gets grounded out when you fully depress the clutch. Listen to the engine closely when you crank it. if something doesn't sound right, don't run it! you might have forgotten to torque the flywheel or something.. think the entire process through to eliminate what funny "clunking" noises might be before you run it!
(*) First run"
- Ok, I know you want to test out the manual, but for the first couple hundred miles, take it easy on the clutch; baby it into gear. Even if it is a used clutch and flywheel, it isn't lined up exactly like it was before! let it burn off burrs and ridges so the clutch seats properly before you go ripping through gears, if the clutch plate grabs on a burr at high rpms, your going to crack one of the "brake pads" on the plate, or even worse, crack your flywheel! Riding the clutch speeds up this process, but over-heating the flywheel can do damage too, so space it out, so it grinds into place properly.

After getting it running with my auto ecu, I drove it to the honda dealership, and walked them through using the pgm tester to rewrite my manual ECU with the correct immob codes. The jerks charged me $75 to teach them how to do their job! gah!

Once I was running on my manual ECU, I kept getting surging idle after the engine warmed up. My first thought was that it was the IACV; so I cleaned it out, and it seemed to fix it for a couple of days. I pulled it off again, and it was still clean, but the surging idle continued when the engine was hot. Next I moved to the EVAP system. When the engine got hot, I heard alot of sucking noises coming from the EVAP Purge Sol. Valve, and when I unplugged it, it stopped surging. if I let it run for a few minutes, then plugged the evap purge sol valve back in, it would run smoothly for a few hours, then start surging again until I unplugged the valve again. I still don't know what the problem is, so I ran my old "ECU Reset" switch to the sol valve wires that run to the ecu, so I can "unplug" the sol valve from the car... After running for a few hundred miles with the sol valve plugged in, I'm getting a P0441 CEL, saying something about incorrect purge flow direction in the EVAP system. I think I knocked something loose when I was putting the clutch hyd. line in behind the evap system; or it could be the fact that I'm running an AEM fuel rail and AEM FPR now; but the fuel pressure has not changed... I have not had a chance to do any homework on this issue yet.

Also, while I had the center console torn appart, I ran some 2GUA wire from the alternator hot line, through the firewall behind the intake manifold, through the center console, under the back seat, to the trunk, for my amps. The whole run is only about 10 feet now, as opposed to the 22 foot 8gua I used to use; and it seemed to clean up the power alot, reducing the mech. vibration from my subs. I also tac'd a piece of square tube in my trunk, and bolted my sub box down, so it doesn't vibrate against the trunk floor any more.

Next, I screwed a 600w power inverter down, to that little plastic console in the back seat, pulled the switch apart, and ran a relay off of the ign2 wire, so it supplies 110v when the key is in ON/START

Next, I ran the stock Eng. Oil Pressure sensor line to the light in my Autometer Engine Oil Pressure guage, with the hot line running to IGN2; so basically, whenever the Engine Oil Pressure light is on, on the dash, my guage lights up too, to draw more attention to the fact that I have no oil pressure. (thought it would be a nice touch). The piping for the actual guage was hard. I used a 90 degree 1/8" BSPT fitting, to a T adapter, with the stock sender in one side, and a 1/8" BSPT to 1/4" NTP adapter on the other side feeding my guage.

Next, I ran my Fuel/Air ratio guage power lines from IGN2, to a hard ground, with the signal line running across the front of the firewall, to the PO2S+ input on the ECU... I might have to use a different guage tho; the bouncing back and forth from lean to rich is distracting while driving.... but it's fun to watch it build on rich when the fuel supply system goes into closed loop

I also ran a cheap ($40) USB GPS receiver from the dash, under the center console, to a hole in the center console, and bolted a powered USB hub in the little cubby hole; leaving 4 USB ports open, and the 3 internal ports running to the GPS, ELMSCAN, and webcam above the license plate in the back. The Hub I got odly enough used a 12vdc power adapter, so I tied it from IGN2 to ground, so it pushes power whenever the car is in ON or START. Right now, the hub is just ran to a usb cable that hangs out the side of the center console to hook up to my tablet; which I brought with me to IRAQ, so I can do some software dev, to get everything to fit on one screen; and find a way to tie a software trigger to the transmission's reverse switch, to fullscreen the webcam prieview screen (back-up camera)

Also, I re-arranged the dash a bit, by moving the radio up next to the clock, and installing a 8" lilliput touchscreen where the radio was.

End result will be re-enforcing my 8" lilliput into the dash, and bolting in a dock for my LE1600 along side it; and running everything from the computer. Only part that kinna sucks is, the LE1600 is a digitizer (requires a pen), but the lilliput is a true touchscreen... I'll prolly use the lilliput for radio controls, and the LE1600 for GPS/ELMSCAN/Back-up Camera. I plan on moving my head unit up to that dead space next to the clock, but after doing some fab work, I figured it is going to take a LONG time. I got the radio mounted there, but I'm too affraid to cut the surface of the cover, as it won't have a "finished" look. As of now, I just keep the cover off. I mounted the radio so the bottom would be flush with the surface of the cover, and the top sticks out; but I need to find a half-decent looking bezel before I go hacking up my only cover.

The 8" lilliput fits perfectly where the radio used to go, but I tend to tap the screen when I shift to 3rd... I'll prolly just adjust my shift linkage to bring the shifting points further away from the dash; but I didn't have enough time to be picky while I was in the states. I also need to finish fab'n the mount for the lilliput; ATM, I just hacked off the existing radio bracket, and used some 3/4" universal bracket tin, and some 2-sided tape to hold it in place... That doesn't even come close to my standards of durability! When I push on the corner of the screen, the mounts give; and I'm waiting for the cheap universal tin I used to break, lol

All in all, I would say that considering that I've never so much as seen a transmission up close before, the swap was a great success, and I learned a TON about my car!

Update (8 OCT 2008): I found out what the issue with the surging idle was. As it turns out; 97's and 99's run a slightly different circuit for the EVAP Purge Control Solenoid. The circuit is inverted in 98+ vehicles. As such, it is effectively holding the purge valve open continously. Easy Fix: $1.25 relay from radio shack.


07-22-2009, 06:28 PM
I did it a few years back.....was fun but not worth the hassle. Although I got the JDM tranny with LSD :drool:

07-29-2009, 12:20 PM
I had mine done at speedtech in calgary by Pat. You could do it for abour $4K...